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The cost and feasibility of marine coastal restoration
Ecological Applications
Supplementary resources (2)
Data
November 2015
Data
November 2015
... Restoring and monitoring of marine habitats often involves working in a highly dynamic environment, inducing economic and logistical constraints, and may involve focal species with narrow environmental tolerances for which we have limited in-depth scientific knowledge available relative to e.g. terrestrial species (Bayraktarov et al., 2015;Danovaro et al., 2021). Collectively, these difficulties often result in high variations in restoration success rates within the marine environment (Bayraktarov et al., 2015), which in turn may lower incentives for investments from stakeholders into marine restoration projects (Blignaut et al., 2013). ...
... terrestrial species (Bayraktarov et al., 2015;Danovaro et al., 2021). Collectively, these difficulties often result in high variations in restoration success rates within the marine environment (Bayraktarov et al., 2015), which in turn may lower incentives for investments from stakeholders into marine restoration projects (Blignaut et al., 2013). Despite these challenges, the active restoration of marine habitats represents a major part of the interventions needed to rebuild marine life in the twenty-first century (Duarte et al., 2020). ...
... Abelson et al., 2016;Hale et al., 2019) and the success of restoration efforts is significantly challenged by the inherently dynamic conditions of the marine environment(Bayraktarov et al., 2015). The majority of restoration efforts within marine systems involves the revegetation of native marine plants or the removal of invasive plant species(Hale et al., 2019), while reef restoration constitutes a smaller proportion and has been mainly limited to biogenic reef (i.e. ...
... However, interdisciplinary research among restoration ecology, society, and economy is lacking. While Spurgeon (1999) and Bayraktarov et al. (2016) had carried out some surveys about the cost and benefit of restoration, they focused on different marine and coastal ecosystems. Similarly, Su et al. (2021) analyzed the cost and benefit of mangrove restoration. ...
... As for the restoration cost, to eliminate the impact of inflation and regional disparity, we used consumer price index (CPI), purchasing power parity (PPP), and discount rate (DIS) to convert all value data into 2020 (base year). The calculation methods of three indices were derived from Hanley and Black (2006); Bayraktarov et al. (2016), and Wei et al. (2018). More details are shown in the supplementary material. ...
... Some scholars believe that largescale restoration size would diminish and share construction and management expenses as a result of the economy of scale theory, which is more thrifty (Berger, 1997). However, other scientists find no obvious linear relationship between restoration area and restoration cost per unit area (Bayraktarov et al., 2016). In this study, salt marsh restoration projects are dominated by small-scale experimental restoration, ranging from 1 ha to 76,000 ha. ...
Restoring degraded and damaged salt marshes has become an important initiative in the coastal wetlands management around the world. Evaluating the economic output of salt marsh restoration is of great significance for identifying the current state of knowledge gaps related to conservation activities and economic benefits. To address this question, we conducted an overview of global salt marsh restoration projects, and their financial expenses and restoration benefits in the past 40 years. The results showed that most of the saltmarsh restoration projects are near megacities and larger rivers, and restoration techniques of different regions depend on the types of disturbance factors such as climate change, extreme weather events, and land use change. With limited resources, fund allocation between protected areas and unprotected areas in middle-income countries is often unbalanced, indicating a mismatch between conservation efforts and regional needs. Although restoration projects are expensive, the evidence in this article implies that most salt marsh restoration projects could recover their financial expense in the finite time, especially for large-scale restoration activities. Besides, the great carbon sequestration potential would make salt marsh restoration projects more profitable under current efforts to promote carbon sequestration for combating global warming.
... The success of most active coral restoration actions is mainly evaluated in terms of transplant survival. In tropical shallow coral reefs, highly successful restoration entails survival of more than 85% of restored corals, while failure occurs if less than 10% of restored corals survived after 5 years (Bayraktarov et al., 2016). However, beyond survival of restored organisms, there is active discussion to define appropriate metrics to properly evaluate restoration success (Fonesca et al., 2002;Elliott et al., 2007). ...
... However, beyond survival of restored organisms, there is active discussion to define appropriate metrics to properly evaluate restoration success (Fonesca et al., 2002;Elliott et al., 2007). Indeed, success of ecological restoration should be measured in terms of recovery of ecosystem function after the restoration effort, monitoring recovery trajectories and comparing with reference control sites (Kaly and Jones, 1998;Ruiz-Jaen and Mitchell Aide, 2005;Bayraktarov et al., 2016). Monitoring must be standardized, holistic, and linked to the objectives/goals set at the beginning of the restoration project. ...
... Monitoring allows for the improvement of transplantation techniques and provides guidance for future restoration efforts (Collier et al., 2007). Most active restoration projects, including coral reefs, seagrasses, mangroves, saltmarshes, and oyster reefs, are generally short-term projects, limited to 1 or 2 years of duration (Bayraktarov et al., 2016). Of 362 case studies on shallow coral restoration, 60% reported less than 18 months of monitoring of restored sites (Boström-Einarsson et al., 2020). ...
Cold-water coral (CWC) habitats dwell on continental shelves, slopes, seamounts, and ridge systems around the world’s oceans from 50 to 4000 m depth, providing heterogeneous habitats which support a myriad of associated fauna. These highly diverse ecosystems are threatened by human stressors such as fishing activities, gas and oil exploitation, and climate change. Since their life-history traits such as long lifespan and slow growth rates make CWCs very vulnerable to potential threats, it is a foremost challenge to explore the viability of restoration actions to enhance and speed up their recovery. In contrast to terrestrial and shallow-water marine ecosystems, ecological restoration in deep marine environments has received minimal attention. This review, by means of a systematic literature search, aims to identify CWC restoration challenges, assess the most suitable techniques to restore them, and discuss future perspectives. Outcomes from the few restoration actions performed to date on CWCs, which have lasted between 1 to 4 years, provide evidence of the feasibility of coral transplantation and artificial reef deployments. Scientific efforts should focus on testing novel and creative restoration techniques, especially to scale up to the spatial and temporal scales of impacts. There is still a general lack of knowledge about the biological, ecological and habitat characteristics of CWC species exploration of which would aid the development of effective restoration measures. To ensure the long-term viability and success of any restoration action it is essential to include holistic and long-term monitoring programs, and to ideally combine active restoration with natural spontaneous regeneration (i.e., passive restoration) strategies such as the implementation of deep-sea marine protected areas (MPAs). We conclude that a combination of passive and active restoration approaches with involvement of local society would be the best optimal option to achieve and ensure CWC restoration success.
... Coral restoration monitoring has not yet fully evolved to a level commensurate with the growth of restoration outplantings. The most commonly used monitoring techniques that are currently in practice focus solely on coral colony level metrics, which lack the ability to capture ecosystem-level benefits of large-scale coral restoration projects (Abelson, 2006;Bayraktarov et al., 2016;Boström-Einarsson et al., 2018;Bayraktarov et al., 2019). As the gap in being able to report success of restoration at an ecosystem level has become more evident, the application of broader scale coral reef monitoring metrics (e.g., benthic community characteristics, shoreline protection, and socioeconomic benefits) and new and advanced technology, including remote sensing and large area imaging (e.g., photomosaics), are beginning to be discussed and more widely applied (Ferse, 2008;Yap, 2009;Fadli et al., 2012;Gintert et al., 2012;Griffin et al., 2016;Miller et al., 2016a;Montoya-Maya et al., 2016;Opel et al., 2017;Foo and Asner, 2019). ...
... Currently, most restoration programs define restoration success or answer the question of "Is the restoration working" by utilizing only colony survival and growth, regardless of the defined goals. While this is appropriate for determining attachment success and short term survival, many of the defined goals, Ecological Restoration, for example, need to be assessed using additional factors to accurately define the success of a program (Ruiz-Jaen and Aide, 2005;Bayraktarov et al., 2016). For example, branching corals, in particular Acropora cervicornis, which is the most commonly used species in Caribbean coral restoration, are known to frequently fragment or become dislodged by natural occurrences ending up relocated 10's of meters from the location it was outplanted (Lirman, 2000;Goergen and Gilliam, 2018). ...
... The proposed restoration Goal-Based Performance Metrics are most valuable if included as part of a controlled restoration experiment, in which various outplanting treatments are replicated and compared to control plots where no restoration has been conducted (Bayraktarov et al., 2016). Another option is to utilize the BACI design (Eberhardt, 1976;Green, 1979) by conducting initial surveys of the area to be restored for comparison to data collected immediately after restoration or during long-term monitoring. ...
As coral restoration efforts continue to increase in size and
number, there is an overwhelming need to define restoration
success and determine progress towards successful restoration.
Meaningful, consistent, comparable, and quantitative data is
required to quantify the changes that result from restoration
actions. However, there may be many definitions of success
depending on the program or project goal(s). Restorations
can have one or many goals that can be very different (e.g.,
ecological, educational), and therefore, goals cannot be
addressed in a “one size fits all” monitoring approach. The
application of quantitative approaches to monitoring not only
provides a reliable way to evaluate progress towards restoration
success, but also provides means to identify problems and apply
adaptive management efforts as needed.
The CRC established a priority for the Restoration Monitoring
Working Group to develop guidance for monitoring coral
reef restorations and to determine restoration success. This
“Coral Reef Restoration Monitoring Guide: Best Practices
for Monitoring Coral Restorations from Local to Ecosystem
Scales” was developed for practitioners and programs in any
stage of their practice: from starting up a new restoration effort,
to scaling up current efforts, to improving efficiency. Coral
restoration practitioners can use the hypotheses- and datadriven
monitoring framework presented in this Guide to make
confident comparisons between projects, programs, and regions,
increase the efficiency of data collection, and make informed
decisions about the data necessary to describe the success of
the restoration goal or objective.
Two categories of coral restoration monitoring metrics are
included in this Guide: Universal Metrics and Goal-Based
Performance Metrics. The four Universal Metrics, Landscape/
Reef-level, Population-level, Colony-level, and Genetic and
Genotypic Diversity, are suggested as basic requirements for
monitoring all restoration projects, regardless of the goal of the
project. These metrics provide data on restoration scale, growth,
survival, and diversity, yet require minimal equipment and time.
These Universal Metrics should be monitored on any restoration
project regardless of the restoration scale, species, habitat,
location, expertise, or budget.
Goal-Based Performance Metrics address five major coral
restoration goals: Ecological Restoration, Socioeconomic, Eventdriven
Restoration, Climate Change Adaptation, and Research.
Metrics are tailored within each goal to address key components
of the goal. For example, when monitoring a restoration with an
ecological goal, a practitioner should evaluate coral condition,
species diversity, habitat quality, and vertebrate and invertebrate
communities, and potentially others. Metrics are detailed for
each goal including key points, suggested methods, reporting
guidelines, and criteria to evaluate the performance towards the
restoration goal and towards restoration success.
Coral reef restoration, while a quickly growing field, is
still relatively new. This document is the first to provide
comprehensive guidance for monitoring coral restorations to
evaluate progress towards meeting restoration goals. Metrics
and associated methods developed herein are based on our
experiences, working group and workshop input, practitioner
interviews, and current published peer reviewed literature and
manuals. While every effort was made to address every situation,
we recognize that as this field develops and the metrics are fully
vetted, some metrics may need to be improved, modified, or
deemed unnecessary. We therefore encourage the evolution of
this Guide as a living document to be updated when necessary
to be relevant and representative. Our experiences and the
examples provided are mainly from the greater Caribbean
region; however, reviews and feedback from practitioners who
have worked globally indicate that the metrics developed are
applicable on coral restorations in all regions.
This Guide should be used to measure and describe the
progress of coral restoration projects towards meeting restoration
goals. The CRC Monitoring Working Group has also developed
a Coral Restoration Database and Evaluation Tool to be
complementary to this Guide and used together. The Coral
Restoration Database allows the input of comparable restoration
projects and monitoring data. The Coral Restoration Evaluation
Tool allows the practitioner to score the performance of their
project, program, or region and determine what is working
well and what needs improvement. The use of this Guide and
feedback provided by practitioners will improve the evaluation of
coral restoration success.
... First, the cost of restoring seagrass meadows tends to be higher than for coral reefs. To illustrate, while restoring 1 hectare of coral reefs is estimated at approximately US $11,717, the restoration of an equivalent area of seagrass meadows has been projected at an astonishing cost of roughly US $2,879,773 (Bayraktarov et al., 2015). Furthermore, the disparity in funding invested between seagrass meadows and coral reefs is also quite impactful. ...
... To put it in perspective, for every 16 seagrass-related publications, 100 studies focused on coral reefs have been published. Second, the success of seagrass meadow restoration is lower than that of coral reef restoration projects (Bayraktarov et al., 2015). ...
Background
Seagrass meadows, known for providing essential ecosystem services like supporting fishing, coastline protection from erosion, and acting as carbon sinks to mitigate climate change effects, are facing severe degradation. The current deteriorating state can be attributed to the combination of anthropogenic activities, biological factors ( i.e ., invasive species), and natural forces ( i.e ., hurricanes). Indeed, the global seagrass cover is diminishing at an alarming mean rate of 7% annually, jeopardizing the health of these vital ecosystems. However, in the Island Municipality of Culebra, Puerto Rico, losses are occurring at a faster pace. For instance, hurricanes have caused over 10% of cover seagrass losses, and the natural recovery of seagrasses across Culebra’s coast has been slow due to the low growth rates of native seagrasses ( Thalassia testudinum and Syringodium filiforme ) and the invasion of the invasive species Halophila stipulacea . Restoration programs are, thus, necessary to revitalize the native seagrass communities and associated fauna while limiting the spread of the invasive species.
Methods
Here, we present the results of a seagrass meadow restoration project carried out in Punta Melones (PTM), Culebra, Puerto Rico, in response to the impact of Hurricanes Irma and María during 2017. The restoration technique used was planting propagation units (PUs), each with an area of 900 cm ² of native seagrasses Thalassia testudinum and Syringodium filiforme , planted at a depth between 3.5 and 4.5 m. A total of 688 PUs were planted between August 2021 and August 2023, and a sub-sample of 88 PUs was monitored between August 2021 and April 2023.
Results
PUs showed over 95% of the seagrass survived, with Hurricane Fiona causing most of the mortalities potentially due to PUs burial by sediment movement and uplifting by wave energy. The surface area of the planting units increased by approximately 200% ( i.e ., 2,459 cm ² ), while seagrass shoot density increased by 168% ( i.e ., 126 shoots by PU). Additionally, flowering and fruiting were observed in multiple planting units, indicating 1) that the action taken did not adversely affect the PUs units and 2) that the project was successful in revitalizing seagrass populations. The seagrass restoration project achieved remarkable success, primarily attributed to the substantial volume of each PUs. Likely this high volume played a crucial role in facilitating the connection among roots, shoots, and microfauna while providing a higher number of undamaged and active rhizome meristems and short shoots. These factors collectively contributed to the enhanced growth and survivorship of the PUs, ultimately leading to the favorable outcome observed in the seagrass restoration project.
... Mangrove restoration has a significant role in climate change mitigation (Taillardat et al., 2020). Such projects are typically the largest and the least expensive per hectare (Bayraktarov et al., 2015, Stewart-Sinclair et al., 2021 and extensive areas of deforested mangrove areas are suitable for restoration (Worthington and Spalding, 2018). Furthermore, unsuitable sites for mangrove restoration characterized by altered hydrological conditions, high wave and flow energy, and inadequate substrate (Bayraktarov et al., 2015) might be ameliorated by saltmarsh presence (Begam et al., 2017;Renzi et al., 2019). ...
... Such projects are typically the largest and the least expensive per hectare (Bayraktarov et al., 2015, Stewart-Sinclair et al., 2021 and extensive areas of deforested mangrove areas are suitable for restoration (Worthington and Spalding, 2018). Furthermore, unsuitable sites for mangrove restoration characterized by altered hydrological conditions, high wave and flow energy, and inadequate substrate (Bayraktarov et al., 2015) might be ameliorated by saltmarsh presence (Begam et al., 2017;Renzi et al., 2019). Thus, an increasing effort should be addressed to understand the potential of saltmarsh facilitation on mangrove restoration. ...
Mangroves and saltmarshes are two of the most relevant coastal habitats for humans. These ecosystems offer several services like coastal protection, climate mitigation, and nursery habitats for many artisanal and commercially exploited fish, crabs, and shellfish. They mostly dominate different latitudinal ranges but in several places around the world they co-occur and interact. Here, we summarize the current scientific knowledge on mangrove-saltmarsh ecological interactions and propose a conceptual model. We screened 1410 articles from 1945 to 2022 and selected 29 experiments that assessed mangrove-saltmarsh ecological interactions. Both
positive and negative interactions are observed but there is variation along different mangrove life stages. Higher retention and establishment of mangrove propagules are found inside saltmarshes than on bare flats, i.e. facilitation, and these effects are higher at grass than at succulent saltmarsh species. Mangrove seedlings, saplings, or trees mostly compete with saltmarshes, negatively affecting mangrove growth. We propose a model with different outcomes considering the interaction between different mangrove’s life stages and saltmarsh forms and discussed these interactions in the light of anthropogenic threats and climate change.
... The patterns in species and functional diversity reported here suggest that restoration is an important strategy in mitigating biodiversity losses and reinstating part of the lost functionality. Due to the limited restoration examples, marine restoration success is often based on short-term periods (1-2 years on average, Bayraktarov et al., 2016;Kollmann et al., 2016, but see Saunders et al., 2020. In terrestrial projects, however, the time elapsed since restoration started has been a key factor to reach similar conditions as those found in reference systems (Martin et al., 2013;Crouzeilles et al., 2016). ...
... Each point represents a functional entity and point sizes are proportional to the relative abundance (measured as dry weight). Also derived from the short-term evaluations, especially in marine ecosystems, restoration success often considers parameters related to the target species' survival, with common measures of growth or density of the individuals (Bayraktarov et al., 2016;Jacob et al., 2018;Cebrian et al., 2021). In terrestrial ecological restoration, vegetation structure is also the most common quantitative indicator (Ruiz-Jaen & Aide, 2005; Gómez-Aparicio, 2009) together with community measures such as the species richness, the biodiversity indices and the species composition (Gatica-Saavedra et al., 2017;Hughes et al., 2017). ...
Active restoration actions are becoming increasingly common for the recovery of degraded ecosystems. However, establishing when an ecosystem is fully restored is rarely achieved, since the recovery of entire communities needs long-term trajectories. The lack of evidence of success is even more severe in marine ecosystems, especially in the context of macroalgal forests, where beyond the vegetation structure and species diversity there is no approximation determining the recovery of the overall functionality. Trait-based ecology facilitates the link between species composition and ecosystem functions and processes. In this study, we used a trait-based approach to assess functional recovery ten years after the start of a restoration action in a marine macroalgal forest. Species and functional diversity were compared among the restored locality, a nearby locality where the expansion of the restoration is naturally occurring, a neighbouring non-restored locality (at a distance of a few meters), and the only two remaining localities dominated by the same structural macroalga that were used as reference (non-perturbed). Species diversity and composition of the restored locality were similar to those found in reference macroalgal forests, while the non-restored and expansion locality showed different species composition and lower species diversity. Functional richness was 4-fold higher in the restored locality than in the non-restored one, even surpassing one reference macroalgal locality. The restored locality showed a greater number of trait categories, especially traits related to higher structural complexity and longer life spans, indicating changes in ecosystem functions and processes. The restoration of a canopy-forming macroalga is the first step to achieving the recovery of an entire macroalgal forest (i.e., associated species and functional diversity). The application of traditional taxonomical indices plus functional parameters provides useful insights into the assessment of the success of restoration actions at the community level, emerging as a promising approach to be replicated and contrasted in other marine and terrestrial ecosystems.
... Effectiveness and success are key concepts in restoration ecology, but difficult to quantify because they are strictly related to the period of monitoring, which often has a limited duration, and due to the absence of univocal indicators to assess what was expected (Bayraktarov et al., 2016;Abelson et al., 2020;Basconi et al., 2020). The results gained through the monitoring activities are extremely limited in time; they must be evaluated with caution, assessing the survival rate of the nuclei on the pipeline and the structure of the assemblages after one year from the intervention exclusively. ...
... health and well-being (Possingham et al., 2015). However, active marine habitat restoration has extremely high costs (Bayraktarov et al., 2016) that in deep habitats are estimated to rise by two or three orders of magnitude per hectare if compared to the costs of activities carried out in coastal marine ecosystems (Van Dover et al., 2014;Danovaro et al., 2021;Montseny et al., 2021). The potential of recovery actions, proven by positive outcomes of worldwide efforts carried out both on land and underwater, together with the need to reverse the trend of ecosystems degradation, are the pillars of the UN Decade on Ecosystem Restoration 2021-2030: a global rallying cry to heal our planet (https://www.decadeonrestoration.org/). ...
The need for habitat recovery in coastal areas, especially those subjected to intensive exploitation, has increased because of significant historical loss and alteration of habitats and, therefore, adverse ecological impacts. The present study defines a stepwise approach to mitigate habitat loss in deep coastal environments, describing the planning, intervention, and monitoring phases following the Trans Adriatic Pipeline (TAP) laying along the Apulian coast (Adriatic Sea, Italy). Preliminary field activities encompassed morpho-bathymetric data (MBES and SSS), SCUBA and ROV observations to accurately map and characterize the mesophotic reefs built by invertebrates found in the area. The pipeline route interfered with 30 outcrops between 50 and 80 m depth, mostly colonized by 15 taxa/morphological groups. A functional/conservative approach was adopted to recognize the taxa/morphological groups on which to focus the removal and following relocation activities based on their abundance, conservation status, and functional traits. Saturation divers teams, ROV pilot technicians, and researchers collaborated to minimize the physical impact and the loss of organisms due to the pipeline installation. They relocated a total of 899 living portions (nuclei) from the 30 interfered reefs on the top of the pipeline. The following monitoring activities, carried out after fourteen months since the intervention, revealed a high mean survival rate (88.1%) and slight variations in the structure of the nuclei assemblages. This study represents a paradigmatic case of involvement and support of the private oil and gas sector to mitigate habitat loss in the Mediterranean Sea, and stresses the need for integrated management involving different stakeholders to mitigate the effects of the exploitation of marine resources through ante operam assessment and active restoration actions.
... The goal of restoration is to improve the recovery of the health and ecological status of damaged populations or communities. Active restoration measures in marine ecosystems are a growing interest of ecologists, who have carried out several experiments transplanting charismatic taxa characteristic of coastal ecosystems (Bayraktarov et al. 2015;Gerovasileiou et al. 2019) with a high potential to provide a wide range of marine ecosystem services. Posidonia oceanica (L.) Delile, 1813 meadows and coralligenous reefs represent the two endemic Mediterranean ecosystems where most active restoration actions have been carried out by transplanting habitat-forming species (Montero-Serra et al. 2018;Boudouresque et al. 2021). ...
... Thus, reducing sources of disturbance should be the first and mandatory management action to achieve restoration and to allow recovery through time (Hawkins et al. 1999). Although the success of ecological restoration should be reasonably assessed over longer monitoring times (Suding, 2011;Bayraktarov et al. 2015), >80% survival 2.5 years after transplantation is very encouraging, and will hopefully instigate further initiatives at larger spatial scales. ...
The assessment of effective and affordable restoration interventions is pivotal to developing new tools to mitigate habitat loss and enhance natural recovery. Gorgonians create important three-dimensional habitats in the Mediterranean Sea providing several ecosystem services associated with coralligenous reefs. Transplantations of the octocorals Eunicella cavolini, E. singularis, and Paramuricea clavata were carried out at the site impacted by the wreck of the Costa Concordia in 2012. A total of 135 by-caught gorgonians, caught in the gears of local artisanal fishermen or found lying on the seabed by SCUBA divers, were transplanted on impacted coralligenous reefs between 20 and 35 m depth and monitored for 2.5 years. A high survival rate (82.1%) was recorded, with main losses attributable to the detachment of the organisms from the substrate rather than death of the colonies. Eunicella cavolini transplanted colonies and natural colonies used as controls were monitored and showed similar, and seasonally influenced, growth and healing rates. Epibiosis and necrosis events were reported in both transplanted and natural colonies during summer, highlighting the sensitivity of the species to thermal stress. The present study emphasizes the importance of a management framework as a stepping-stone to achieve effective restoration outcomes, including the removal of pressures that caused changes in natural communities and the participation of local stakeholders. The effectiveness of the methods and procedures proposed in this work allowed the restoration activities to continue at a larger scale during summer and autumn 2020.
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... Excluding restoration of large offshore islands and current and former salt ponds, which provide the least clear benefits 31 , the total area of restoration is 367 ha. Based on a conservative estimate of restoration costs in developed countries, restoring this area of marsh would cost on the order of $70 million, or about $200,000 per hectare (in 2021 USD) 32 , which is an order of magnitude lower than present value of restoration with 1.0 m SLR. In contrast, previous work indicates that the cost of www.nature.com/scientificreports/ ...
The use of nature-based solutions (NBS) for coastal climate adaptation has broad and growing interest, but NBS are rarely assessed with the same rigor as traditional engineering solutions or with respect to future climate change scenarios. These gaps pose challenges for the use of NBS for climate adaptation. Here, we value the flood protection benefits of stakeholder-identified marsh restoration under current and future climate change within San Francisco Bay, a densely urbanized estuary, and specifically on the shores of San Mateo County, the county most vulnerable to future flooding in California. Marsh restoration provides a present value of $21 million which increases to over $100 million with 0.5 m of sea level rise (SLR), and to about $500 million with 1 m of SLR. There are hotspots within the county where marsh restoration delivers very high benefits for adaptation, which reach $9 million/hectare with likely future sea level and storm conditions. Today’s investments in nature and community resilience can result in increasing payoffs as climate change progresses and risk increases.
... Insufficient funding was commonly viewed as a factor limiting restoration success across our interviews (Bayraktarov et al., 2015;Brancalion et al., 2019;Cabin et al., 2010). We, however, suggest that the relationship between the amount of money invested and outcomes is not necessarily linear (Bayraktarov et al., 2019) and funds need to be thoughtfully allocated both within and among projects. ...
Governmental and non-governmental organizations spend considerable funding on restoring ecosystems to counter biodiversity loss, yet outcomes are often not assessed at a regional scale. Monitoring is done ≤5 years after project-implementation, if at all, and rarely assesses the effects of management practices on project success. We combined vegetation surveys and management interviews to compare long-term restoration outcomes of 37 California coastal grassland projects (5-33 y post-implementation) that spanned a 1000-km north-south gradient. We found that coastal grassland restoration is largely successful at reaching project goals (95 %) and a standard performance metric (80 %) to restore native cover, but land managers preferentially use a small number of well-tested, "high success" species, potentially at the expense of regional diversity. Medium and high maintenance intensity resulted in lower non-native cover and improved native cover and rarefied native richness. Managers of voluntary (non-statutory) sites were more open to assessing outcomes and spent less per hectare compared to legally mandated (statutory) projects but achieved similar plant cover and even higher rarefied richness. Statutory project managers indicated that regulatory agencies sometimes lowered compliance goals for native cover if the initial targets were not met. Additional funding for greater maintenance intensity and incorporating more locally distinctive species (i.e., endemic or range-restricted) may help counteract potential unintended consequences from preferential plant selection, and inter-agency coordination of species selection could reduce biotic homogenization. We recommend delegating funds to a third-party monitoring group to ensure legally mandated compliance and consistency in assessment.
... To prevent and reverse further losses, seagrass restoration efforts, using sods and rhizome fragments, are being undertaken across the world (Valdez et al., 2020). Nonetheless, the success rates of these efforts remain generally low (Bayraktarov et al., 2015;Valdez et al., 2020;van der Heide et al., 2007) and are mostly focused on decreasing environmental (e.g., hydrodynamic forces) and physiological stressors (diseases) on seagrasses on a small spatial scale Marion et al., 2020;Statton et al., 2017). In contrast, biotic interactions, which could also affect restoration success, are less well studied (Gagnon et al., 2020;Statton et al., 2017;Valdez et al., 2020). ...
Seagrasses are globally declining and multiple restoration efforts are undertaken to reverse these losses. However, these efforts have proven to be challenging, facing a variety of bottlenecks. We studied how predation by macroinvertebrates may form a potential bottleneck for seed-based seagrass restoration. Specifically, we questioned if the omnivorous common ragworm (Hediste diversicolor) may act as a predator on eelgrass (Zostera marina) seeds and whether that could affect seed-based eelgrass restoration trials. In a controlled lab experiment, we studied (1) how seedling establishment was affected by ragworm biomass (0, 2, 8 g DW m⁻²), (2) if the absence or presence of an additional or alternative high-protein food source (Sanikoi ® Gold Protein Plus, 52% protein) prevented potential seed predation by ragworms and (3) how ragworm size (small: 0.0029 g and 3.3× bigger: 0.0095 g DW ragworm⁻¹) affected eelgrass seedling establishment. Additionally, we questioned (4) if ragworms may provide a bottleneck for annual eelgrass restoration experiments in the Dutch Wadden Sea by combining data from a large-scale benthic survey (SIBES, Netherlands Institute for Sea Research (NIOZ), Texel) with an existing eelgrass habitat suitability map. We found that >2 g DW m⁻² ragworms completely hampered eelgrass seedling establishment, even when fed an additional, protein-rich, food source. Ragworms only seemed to target sprouted seeds rather than intact seeds. Additionally, sprouted seed consumption by ragworms was size-dependent: sprouted seeds escaped predation by smaller ragworms even when present in high biomass (2 g DW m⁻²). By extrapolating our findings to the field, we showed that 52.8% of the potential eelgrass growth sites in the Dutch Wadden Sea overlap with impeding ragworm biomass (≥2 g DW m⁻²). By consuming sprouted eelgrass seeds, ragworms may consequently strongly impede seed-based eelgrass restoration efforts, especially since both species have highly overlapping distributions. We thus provided novel insights into an unknown bottleneck for seed-based eelgrass establishment, which may have restoration implications. Especially for annual eelgrass that fully depends on successful seedling establishment for their persistence and survival.
... Although seagrass restoration is gaining traction as a conservation tool, its success rate has thus far been limited compared to other marine restoration projects (Bayraktarov et al. 2015). In fact, a global analysis on seagrass restoration by van Katwijk et al. (2016) demonstrated that 37% of trials survived after 36 months, over a total of 1786 restoration trials. ...
Despite active seagrass restoration gaining traction as a tool to halt and reverse worldwide seagrass losses, overall success remains limited. Restoration strategies, through seeding or transplantation, face different environmental bottlenecks that limit restoration success. Choosing the most appropriate strategy of the two for a specific location, however, is hampered by lack of direct practical comparisons between strategies within a single system. To investigate potential life stage dependent bottlenecks, we compared seed‐based and transplant‐based restoration of Zostera marina in the subtidal saltwater Lake Grevelingen. Our results demonstrate that seedling recruitment was negatively impacted by bioturbation from the lugworm Arenicola marina and sediment movement due to hydrodynamic exposure. Transplant‐based restoration was clearly more successful but surprisingly best predicted by leaf gluing by the ragworm Platynereis dumerilii. This previously undescribed interaction caused seagrass leaves to clump, reduce limiting effective photosynthetic surface and leaf movement. We suggest that the observed behaviour of these worms, may result from a lack of natural predators, illustrating the importance of trophic control for seagrass restoration. Thus, in addition to recognizing life stage dependent environmental bottlenecks for restoration strategy selection, seagrass restoration may also require the active recovery of their associated food webs. This article is protected by copyright. All rights reserved.
... Still, as no costs for the respective necessary management interventions area are currently available, it is impossible to present the findings as a costbenefit ratio. Also, while generalised costs to create new marine and coastal habitat are now becoming increasingly available (e.g., Bayraktarov et al., 2015) the myriad of costs involved with improving the ecological status of a habitat or an entire catchment are less attainable, largely due to the many different ways this process can be achieved. We recommend that future research could build on the findings presented here, including more detailed assessments of the costs involved in creating and restoring the habitats. ...
Current approaches to measure ecosystem services (ES) within natural capital (NC) and nature-based solutions (NbS) assessments are generally coarse, often using a single figure for ecosystem services (e.g., nutrient remediation or blue carbon sequestration) applied to the local or national habitat stock, which fails to take account of local ecosystem conditions and regional variability. As such, there is a need for improved understanding of the link between habitat condition and ES provision, using comparable indicators in order to take more informed management decisions. Here the UK, Solent Marine Sites (SEMS) is used as a case study system to demonstrate how Water Framework Directive (WFD) ‘ecological status’ and other indicators of ecosystem condition (state or quality) can be coupled with habitat extent information to deliver a more precise locally-tailored NC approach for active coastal and marine habitat restoration. Habitat extent and condition data are collected for seven NbS relevant coastal habitats (littoral sediment, mat-forming green macroalgae, subtidal sediment, saltmarsh, seagrass, reedbeds and native oyster beds). The workflow includes: 1) biophysical assessment of regulatory ES; 2) monetary valuation; and 3) compilation of future scenarios of habitat restoration and creation. The results indicate that incorporating classifications by condition indices into local NC extent accounts improved ES benefits by 11–67%. This suggests that omitting condition from NC assessments could lead to undervaluation of ES benefits. Future scenarios of restoration in the SEMS also show that the additional regulatory benefits of reaching ‘Good’ ecological status are £376 million annually, but could be as much as £1.218 billion if ‘High‘status and all habitat creation targets were met. This evidence of the potential value of restoration and importance of including condition indices in assessments is highly relevant to consider when investing in water ecosystems conservation and restoration as called for by the UN Decade on Ecosystem Restoration (2021−2030), and more generally in global nutrient neutrality and blue carbon policy strategies.
... On the other hand, loss rates of seagrass in Europe have slowed down since the 1980s and the net rate of change in seagrass area experienced a reversal in the 2000s, with density metrics improved or remaining stable in most sites (de los Santos et al., 2019).In spite of the global loss of seagrass, the causes of seagrass loss are manageable to a large extent and threats can be reduced with effective management. In fact, seagrass restoration is increasingly successful, although it is expensive and many large projects have failed historically (success rate: 38%;Bayraktarov et al., 2015;Cullen-Unsworth & Unsworth, 2016;Duarte et al., 2020;Unsworth et al., 2018; van Katwijk et al., 2016). On the other hand, seagrasses can only grow in shallow waters, which constrains the upper limit of their carbon sequestration. ...
The atmospheric concentration of CO2 is steadily increasing and causing climate change. To achieve the Paris 1.5 or 2°C target, negative emission technologies must be deployed in addition to reducing carbon emissions. The ocean is a large carbon sink but the potential of marine primary producers to contribute to carbon neutrality remains unclear.
Here we review the alterations to carbon capture and sequestration of marine primary producers (including traditional ‘blue carbon’ plants, microalgae and macroalgae) in the Anthropocene, and, for the first time, assess and compare the potential of various marine primary producers to carbon neutrality and climate change mitigation via biogeoengineering approaches.
The contributions of marine primary producers to carbon sequestration have been decreasing in the Anthropocene due to the decrease in biomass driven by direct anthropogenic activities and climate change. The potential of blue carbon plants (mangroves, saltmarshes and seagrasses) is limited by the available areas for their revegetation. Microalgae appear to have a large potential due to their ubiquity but how to enhance their carbon sequestration efficiency is very complex and uncertain. On the other hand, macroalgae can play an essential role in mitigating climate change through extensive offshore cultivation due to higher carbon sequestration capacity and substantial available areas. This approach seems both technically and economically feasible due to the development of offshore aquaculture and a well‐established market for macroalgal products.
Synthesis and applications. This paper provides new insights and suggests promising directions for utilizing marine primary producers to achieve the Paris temperature target. We propose that macroalgae cultivation can play an essential role in attaining carbon neutrality and climate change mitigation, although its ecological impacts need to be assessed further.
... For example the cost of planting seagrass was estimated at AUD $10,000-166,000 per hectare in 2005 (D. A. Lord & Associates Pty Ltd, 2005). The median and average reported costs for restoration of one hectare of marine coastal habitat were around US$80 000 (2010) and US$1 600 000 (2010), respectively, the real total costs (median) are likely to be two to four times higher (Bayraktarov et al., 2015). Alternatives to direct planting or translocation includes active indirect on-site restoration techniques such as promoting the recruitment of mangroves, seagrass or coral by deploying suitable substrate and materials. ...
New report applies the mitigation hierarchy and deep-ocean science to determine risks and impacts of deep-seabed mining - Volume 54 Issue 4 - Pippa Howard, Nicky Jenner, Guy Parker
... The terms ecosystemA and ecosystemB were used as placeholders for two different words describing the same ecosystem (e.g., coral and coral reef, mangrove and mangal, saltmarsh and salt marsh, shellfish, and oyster). For consistency with Bayraktarov et al. (2016b), an EndNote (Version X8.1; Thomson Reuters.) search was then performed within the full text using the search terms "(cost * OR feasib * OR surviv * )." Additional information was gathered by following citations, personal communications, and inspecting diverse restoration databases and webpages. ...
Active restoration is becoming an increasingly important conservation intervention to counteract the degradation of marine coastal ecosystems. Understanding what has motivated the scientific community to research the restoration of marine coastal ecosystems and how restoration research projects are funded is essential if we want to scale-up restoration interventions to meaningful extents. Here, we systematically review and synthesize data to understand the motivations for research on the restoration of coral reefs, seagrass, mangroves, saltmarsh, and oyster reefs. We base this analysis off a published database of marine restoration studies, originally designed to estimate the cost and feasibility of marine coastal restoration, derived from mostly scientific studies published in peer-reviewed and some gray literature. For the present study, the database was updated with fields aimed at assessing the motivations, outcomes, and funding sources for each project. We classify restoration motivations into five categories: biotic, experimental, idealistic, legislative, and pragmatic. Moreover, we evaluate the variables measured and outcomes reported by the researchers and evaluate whether projects adhered to the Society for Ecological Restoration's (SER) standards for the practice of ecological restoration. The most common motivation of the scientific community to study restoration in marine coastal ecosystems was experimental i.e., to seek experimental data to answer ecological research questions or improve restoration approach, as expected since mostly peer-reviewed literature was evaluated here. There were differences in motivations among the five coastal ecosystems. For instance, biodiversity enhancement was the most common case for a biotic motivation in mangrove restoration projects. The most common metrics evaluated were growth/productivity, survivorship, habitat function, physical attributes, and reproduction. For most ecosystems, ecological outcomes were frequently reported, with socio-economic implications of the restoration rarely mentioned, except for mangroves. Projects were largely funded by governmental grants with some investment from private donations, non-governmental organizations, and the involvement of volunteers. Our findings and database provide critical data to align future research of the scientific community with the real social, economic and policy needs required to scale-up marine coastal restoration projects.
... In marine systems, the difficulties (logistical and financial) associated with restoration are substantial. Conservative estimates by Bayraktarov et al. (2015) showed that the cost of restoring marine coastal habitat was 80,000 USD per hectare (median), which may be the reason why marine managers have prioritized conservation initiatives over restoration to date. The amount of time, effort, and funds dedicated to the restoration of one ecosystem may restrict the resources available for other conservation activities, and therefore, tools that aid in the prioritization of conservation and restoration targets are needed because the consequences of delaying action may also amount to making a decision. ...
The novel ecosystem (NE) concept has been discussed in terrestrial restoration ecology over the last 15 years but has not yet found much traction in the marine context. Against a background of unprecedented environmental change, managers of natural marine resources have portfolios full of altered systems for which restoration to a previous historical baseline may be impractical for ecological, social or financial reasons. In these cases, the NE concept is useful for weighing options and emphasizes the risk of doing nothing by forcing questions regarding the value of novelty and how it can best be managed in the marine realm. Here, we explore how the concept fits marine ecosystems. We propose a scheme regarding how the NE concept could be used as a triage framework for use in marine environments within the context of a decision framework that explicitly considers changed ecosystems and whether restoration is the best or only option. We propose a conceptual diagram to show where marine NEs fit in the continuum of unaltered to shifted marine ecosystems. Overall, we suggest that the NE concept is of interest to marine ecologists and resource managers because it introduces a new vocabulary for considering marine systems that have been changed through human actions but have not shifted to an alternate stable state. Although it remains to be seen whether the concept of marine NEs leads to better conservation and restoration decisions, we posit that the concept may help inform management decisions in an era of unprecedented global marine change. This article is protected by copyright. All rights reserved.
... International, regional, and state regulations call for restorative actions in degraded habitats, but there are no tested approaches to restore or rehabilitate vent ecosystems (including the overlying water column). Similar efforts on land or in near-shore ecosystems, such as seagrass beds and coral reefs, demonstrate that successful restoration is challenging in better known systems and far more tractable contexts [38,39]. Industrial-scale, active interventions to restore hydrothermal vents in the deep sea, even if logistically feasible, will likely be orders of magnitude costlier per hectare than any effort on land [40]. ...
There is increasing interest in mining minerals on the seabed, including seafloor massive sulfide deposits that form at hydrothermal vents. The International Seabed Authority is currently drafting a Mining Code, including environmental regulations, for polymetallic sulfides and other mineral exploitation on the seabed in the area beyond national jurisdictions. This paper summarizes 1) the ecological vulnerability of active vent ecosystems and aspects of this vulnerability that remain subject to conjecture, 2) evidence for limited mineral resource opportunity at active vents, 3) non-extractive values of active vent ecosystems, 4) precedents and international obligations for protection of hydrothermal vents, and 5) obligations of the International Seabed Authority under the UN Convention on the Law of the Sea for protection of the marine environment from the impacts of mining. Heterogeneity of active vent ecosystems makes it extremely challenging to identify "representative" systems for any regional, area-based management approach to conservation. Protection of active vent ecosystems from mining impacts (direct and indirect) would set aside only a small fraction of the international seabed and its mineral resources, would contribute to international obligations for marine conservation, would have non-ex-tractive benefits, and would be a precautionary approach.
... Given the alarming condition of coastal ecosystems, substantial efforts have been made for protection, restoration, and sustainable use by governmental and private sectors around the world (Zedler, 2000a(Zedler, , 2000bBayraktarov et al., 2015). Importantly, restoration has been increasingly elevated for coastal conservation (Benayas et al., 2009). ...
With accelerating degradation of coastal environment worldwide, restoration has been elevated as a global strategy to enhance the functioning and social services of coastal ecosystems. While many developing countries suffer from intense coastal degradation, current understanding of the science and practice of their coastal restorations is extremely limited. Based on analysis of > 1000 restoration projects, we provide the first synthesis of China's coastal restorations. We show that China's coastal restoration has recently entered a rapidly developing stage, with an increasing number of restoration projects carried out in multiple types of coastal ecosystems. While long-term, national-level restorations enforced by the government appear promising for some coastal ecosystems, especially mangroves, restorations of many other coastal ecosystems, such as salt marshes, seagrasses and coral reefs, have been much less implemented, likely due to under-appreciation of their ecosystem services values. Furthermore, the planning, techniques, research/assessment, and participation models underlying current restorations remain largely inadequate for restoration to effectively halt rapid coastal degradation. To promote success, we propose a framework where paradigms in current restorations from planning to implementation and assessment are transformed in multiple ways. Our study has broad implications for coastal environmental management policies and practices, and should inform sustainable development of coupled human-ocean systems in many countries.
Stakeholder‐led coral reef restoration efforts, aimed at locally retaining or rebuilding coral populations, have rapidly grown over the last two decades. However, the cost‐effectiveness—and in turn viability—of coral restoration projects remains rarely reported. We therefore evaluated coral planting (often termed “outplanting”) cost‐effectiveness across the first 3.5 years of the Coral Nurture Program (CNP), a coral restoration approach integrated within tourism operations on Australia's Great Barrier Reef. CNP operator activity reporting forms (63,632 corals planted, 5 tourism operators, and 23 reef sites) were used to opportunistically calculate coral planting costs (PC; US$ coral ⁻¹ trip ⁻¹ ) for “routine” planting versus when additional stewardship activities—that regulate planting effectiveness—were undertaken (e.g., nursery maintenance). Mean PC (±standard error) was US$2.34 ± 0.20 coral ⁻¹ trip ⁻¹ (ranging US$0.78–6.03, 5th–95th percentile), but increased 2‐ to ‐6‐fold on trips where nursery propagation, site maintenance, or staff training was conducted to support planting efforts. The “realized” cost (PC R ) of establishing coral biomass was subsequently determined by evaluating survivorship of planted corals across space (9 sites, single survey timepoint, n = 4,723 corals up to 3 years old) or over time (2 sites, over 9–12 months, n = 600 corals), resulting in costs increasing from PC to PC R by 25–71%. We demonstrate how integration of practices into tourism operations creates potential for cost‐effective coral planting at “high‐value” tourism reef sites, and discuss important steps for improving cost‐accounting in stakeholder‐led restoration programs that may be similarly positioned to routinely determine their cost‐effectiveness.
Accurately accounting for the many variables which can influence restoration feasibility is critical to achieve desired outcomes, yet robust frameworks to assess feasibility are lacking. In conservation planning, feasibility can be defined as ‘the probability that a project will achieve its stated objectives’. Often, important biophysical, social, governance, logistical, or resource factors that co-vary across space and determine feasibility are not explicitly included in restoration planning, even though this could enhance outcomes. Here, we present a four-step approach to include feasibility into restoration planning, using mangrove restoration as a case study. Step 1 uses expert knowledge and published literature to identify relevant spatial gradients and explore feasibility factors spanning biophysical, governance, social, logistical, and resource realms which influence restoration outcomes. Step 2 describes the functional relationships between specific feasibility factors and spatial gradient(s) of interest. Step 3 assesses how management interventions could increase feasibility of specific factors. Step 4 analyses ‘joint feasibility’ of multiple feasibility factors and identifies whether further management interventions are required. The approach provides a systematic and repeatable evaluation of multiple feasibility factors and is applicable in spatial planning to enhance restoration outcomes.
By removing nutrients from the water, coastal ecosystems serve as a filter between land and the open sea. Seagrasses contribute to the coastal filter by trapping and absorbing nutrients. Understanding the processes and environmental conditions underpinning the variability in nutrient retention among and within seagrass meadows is important to evaluate their role in the coastal filter across geographic regions, especially in less studied regions. This study evaluates the role of eelgrass (Zostera marina) meadows in the coastal filter in boreal Newfoundland, Canada, and identifies environmental traits driving variability in nutrient fluxes. We measured carbon (Corg) and nitrogen (N) proportions and stable isotopic composition in the surface sediment (top 5 cm) of three eelgrass meadows. Sediment cores were collected from different locations (i.e., inside, edge, outside) relative to each meadow. Sediment %N (0.22%), %Corg (2.82%), Corg stock (11.1 Mg Corg ha⁻¹), and N stock (0.91 Mg N ha⁻¹) were elevated in our study sites; however, nutrient content was not consistently higher inside the meadow than at the edge or outside. Variability in nutrient retention was best explained by a negative relationship with sediment bulk density. Additionally, differences in carbon isotopic (δ¹³Corg) enrichment between eelgrass tissue (−11.6‰) and sediment (−22.1‰) within sites indicated that sediment nutrients were predominantly derived from allochthonous marine sources, where variability was best explained by salinity. This study improves the understanding of the role of eelgrass to nutrient cycles in boreal coastal systems and the potential of eelgrass as a blue carbon ecosystem.
Coastal wetland restoration is an important activity to achieve greenhouse gas (GHG) reduction targets, improve water quality, and reach the Sustainable Development Goals. However, many uncertainties remain in connection with achieving, measuring, and reporting success from coastal wetland restoration. We measured levels of carbon (C) abatement and nitrogen (N) removal potential of restored coastal wetlands in subtropical Queensland, Australia. The site was originally a supratidal forest composed of Melaleuca spp. that was cleared and drained in the 1990s for sugarcane production. In 2010, tidal inundation was reinstated, and a mosaic of coastal vegetation (saltmarshes, mangroves, and supratidal forests) emerged. We measured soil GHG fluxes (CH4, N2O, CO2) and sequestration of organic C in the trees and soil to estimate the net C abatement associated with the reference, converted, and restored sites. To assess the influence of restoration on water quality improvement, we measured denitrification and soil N accumulation. We calculated C abatement of 18.5 Mg CO2−eq ha⁻¹ year⁻¹ when sugarcane land transitioned to supratidal forests, 11.0 Mg CO2−eq ha⁻¹ year⁻¹ when the land transitioned to mangroves, and 6.2 Mg CO2−eq ha⁻¹ year⁻¹ when the land transitioned to saltmarshes. The C abatement was due to tree growth, soil accumulation, and reduced N2O emissions due to the cessation of fertilization. Carbon abatement was still positive, even accounting for CH4 emissions, which increased in the wetlands due to flooding and N2O production due to enhanced levels of denitrification. Coastal wetland restoration in this subtropical setting effectively reduces CO2 emissions while providing additional cobenefits, notably water quality improvement.
Restoration of coastal and marine ecosystems is essential to meet both national and global conservation targets and to counteract declines in coastal marine ecosystems. However, despite its status as a world leader in marine protection, Australia is lagging behind other countries in the implementation of coastal and marine restoration.
Effective legislative frameworks that support the implementation of coastal and marine restoration as a management tool remains a key barrier to large-scale implementation of coastal and marine restoration in Australia and many other regions. We analyzed restoration projects and their policy frameworks in Australia, North
America and Europe to identify the range of policy approaches for marine and coastal restoration. We then evaluated the legislative frameworks for coastal and marine restoration in two states in Australia (Queensland and New South Wales), to assess the current restoration permitting process and identify how different legislative
and policy approaches could facilitate coastal and marine restoration projects. We identified two specific areas where improvements could be made to facilitate marine coastal restoration in Australia: increased transparency and better integration into coastal policy. Coastal and marine restoration in Australia is undertaken without appropriate and effective policy at the local, regional and national levels, which likely impedes its broader use as a management strategy. The policy and legislative changes and amendments outlined in this article can
streamline the coastal and marine restoration process and thereby improve uptake of marine and coastal restoration in Australia.
Mangroves provide benefits and various services to local communities living along coastal areas, particularly fishery communities. Fishery community perceptions are significant in determining attitudes towards improving mangrove conditions, which can also be addressed through restoration activities. This research was conducted to analyze fisheries communities perceptions, willingness to pay (WTP) for mangroves restoration, and mangrove forest management strategies. Field surveys were conducted from July-August 2019 and February-March 2020. Primary data were collected from respondents in four regions (Kalianda Regency, South Lampung Regency, Bandar Lampung City, and Pesawaran Regency) in Lampung Province, Indonesia, which consist of fishers, shrimp farmers, crab and wood seekers, and finfish farmers. The respondents were 193 people, and four experts were involved in the policy scenario analysis. Results revealed a gap in the value of WTP among fishery community groups, in which the average value for fishers is lower than shrimp farmers. The years of formal education significantly influenced the WTP for mangrove restoration. Based on the scenario analysis, scenario 01 become a priority strategy, where four policies (P1 = Mangrove ecotourism development in Lampung Bay; P2 = Mangrove knowledge education and training on processing mangrove based products; P3 = Restoration and conservation of mangrove forests; and P4 = Community-based management for mangrove forests utilization) show high likelihoods to be simultaneously implemented for mangroves management, with mangrove ecotourism policy as the most decisive policy. For future research, other explanatory variables can be added, such as information on family member characteristics, and to develop a bottom-up policy scenario by identifying and involving the role of the local community.
Coral restoration is increasingly used globally as a management tool to minimize accelerating coral reef degradation resulting from climate change. Yet, the science of coral restoration is still very focused on ecological and technical considerations, impeding the understanding of how coral restoration can be used to improve reef resilience in the context of socio-ecological systems. Here, we visited four well-established coral restoration projects in different regions of the world (Thailand, Maldives, Florida Keys, and US Virgin Islands), and conducted key-informant interviews to characterize local stakeholder's perceptions of the key benefits and limitations associated with restoration efforts. Our results reveal that perceptions around coral reef restoration encompass far more than ecological considerations, and include all four dimensions of sustainability: ecological, social, economic, and governance, suggesting that effective coral restoration should be guided by the principles of sustainability science. Socio-cultural benefits were the most frequently mentioned (72.4% of all respondents), while technical problems were the most common theme for limitations of coral restoration efforts (58.3% of the respondents). Participants also revealed some key points likely to improve the outcomes of coral restoration efforts such as the need to better embrace socio-cultural dimensions in goal setting, evaluate ecological outcomes more broadly, secure long-term funding and improve management and logistics of day to day practices. While we identify several important limitations of coral reef restoration, particularly around amateur workforces and limited involvement of local communities, our results suggest that coral restoration can be used as a powerful conservation education tool to provide hope, enhance agency, promote stewardship and strengthen coral reef conservation strategies.
Reaching conservation goals critically depends on smart decision-making to efficiently allocate a constrained budget between different on-ground actions leading to maximum net benefit for biodiversity and human well-being at highest probability of success and lowest cost for these actions (Possingham et al. 2001; Joseph et al. 2009; Game et al. 2013). Without information on cost, feasibility and benefits of conservation, a prioritisation of marine coastal restoration interventions will be poor and money lost (Possingham et al. 2001; Game et al. 2013; Bottrill et al. 2011). This article is protected by copyright. All rights reserved.
Mangroves provide vital climate change mitigation and adaptation (CCMA) ecosystem services (ES), yet have suffered extensive tropics-wide declines. To mitigate losses, rehabilitation is high on the conservation agenda. However, the relative functionality and ES delivery of rehabilitated mangroves in different intertidal locations is rarely assessed. In a case study from Panay Island, Philippines, using field- and satellite-derived methods, we assess carbon stocks and coastal protection potential of rehabilitated low-intertidal seafront and mid- to upper-intertidal abandoned (leased) fishpond areas, against reference natural mangroves. Due to large sizes and appropriate site conditions, targeted abandoned fishpond reversion to former mangrove was found to be favourable for enhancing CCMA in the coastal zone. In a municipality-specific case study, 96.7% of abandoned fishponds with high potential for effective greenbelt rehabilitation had favourable tenure status for reversion. These findings have implications for coastal zone management in Asia in the face of climate change.
Macro-economic decisions determine the resources allocated at an international and a country-level to natural resource management. Micro-economic theory and tools are then used to ensure that this allocation will materialize into desired economic, environmental and societal outcomes. Restoration projects differ in their costs and benefits. The costs may entail operational costs, and those associated with alternative foregone opportunities. The benefits of restoration may reflect biodiversity outcomes or the provision of ecosystem goods and services, such as the supply of water and carbon sequestration. Restoration also has the potential to ensure supply of timber and non-timber forest products such as food and medicines, with potential significance for subsistence livelihoods. We synthesise approaches to valuing the costs and benefits of restoration projects in order to explore the economic consequences of restoration decisions and to prioritise investments. We finish the chapter by outlining economic incentives and policies that might support the implementation of restoration activities.
Vegetation changes were monitored over a 13-yr period (1982-1994) in the Campbell River estuary following the development of marshes on four intertidal islands. The marshes were created to mitigate the loss of a natural estuarine marsh resulting from the construction of a dry land log-sorting facility. Plant species coverage was measured along 23 permanent transects in planted and unplanted blocks on the constructed islands, and in naturally occurring low-marsh and mid-to-high marsh reference communities on nearby Nunn's Island. Five dominant species, Carex lyngbyei, Juncus balticus, Potentilla pacifica, Deschampsia caespitosa, and Eleocharis palustris established successfully and increased in cover in both planted and unplanted areas. The planted, unplanted, and Nunn's Island low-marsh sites had similar total plant cover and species richness by the 13th year. Principal components analysis of the transects through time indicated successful establishment of mid-to-low marsh communities on the constructed islands by the fourth year. Vegetation fluctuations on the constructed islands were greater than in the mid-to-high and low-marsh reference communities on Nunn's Island. Results showed that substrate elevation and island configuration were major influences on the successful establishment and subsequent dynamics of created marsh communities. Aboveground biomass estimates of marshes on the created islands attained those of the reference marshes on Nunn's Island between years 6 and 13. However, Carex lyngbyei biomass on the created islands had not reached that of the reference marshes by year 13. Despite the establishment of what appeared to be a productive marsh, with species composition and cover similar to those of the reference marshes on Nunn's Island, vegetation on the created islands was still undergoing changes that, in some cases, were cause for concern. On three of the islands, large areas devoid of vegetation formed between years 6 and 13, probably a result of water ponding. Adaptive management has allowed us to modify the island configuration through the creation of channels to drain these sites in an attempt to reverse the vegetation dieback. These changes, occurring even after 13 years, further underscore the need for caution when considering the trading of existing natural, healthy, productive wetlands for the promise of created marshes that may or may not prove to be equal to the natural systems. Where marsh creation is warranted, we recommend that management of created marshes be adaptive and flexible, including a long-term monitoring program that should continue at least until the annual variation in vegetation of the created marsh is similar to that of natural, nearby systems.
While successful examples of large-scale (5 000-10 000 ha) ecological wetland/mangrove rehabilitation projects exist worldwide, mangrove rehabilitation efforts in Indonesia, both large and small, have mainly failed. The majority of projects (both government programs and non-government initiatives) have oversimplified the technical processes of mangrove rehabilitation, favouring the direct planting of a restricted subset of mangrove species (from the family Rhizophoracea), commonly in the lower half of the intertidal system (from Mean Sea Level down to Lowest Atmospheric Tide) where mangroves, by and large, do not naturally grow. Aside from lack of appropriate technical assessment, these lower inter-tidal mudflats are often targeted for rehabilitation because true degraded mangrove forests are frequently linked to tenurial issues that require significant effort and investment to resolve. Ecological Mangrove Rehabilitation (EMR) has been implemented and well documented for the past several decades in New World mangrove systems (Lewis, 2005, 2009b) and was selected as a best practice for adaptation and trials in Indonesia. Whereas in the US, the five-step process primarily focuses on biophysical assessments and eco-hydrological repair, when applied to the Indonesian scenario, EMR requires both lower-cost biophysical approaches and greater attention to socio-cultural-political approaches common in sustainable development and coastal resource management programs. The adaptation of EMR was initially tested in small-scale projects, ranging from 12-33 ha in sites from the islands of Sumatera and Sulawesi. Biophysical adaptations included use of low-cost biophysical assessment methods, reliance on manual labour, strategic breaching of aquaculture ponds dike walls, manual construction of tidal channels, and human assisted propagule dispersal while socio-political adaptations included land tenure settlement, increased use of training of trainers programs, gender assessments and sensitisation, enhanced community organising, coordination with numerous government agencies and participatory monitoring. Initial projects succeeded in rehabilitating mangrove coverage and diversity, while catalysing community-based or collaborative management. The most recent Community Based Ecological Mangrove Rehabilitation (CBEMR) project took place on Tanakeke Island, South Sulawesi, where 1776 ha of mangroves were reduced to approximately 576 ha over two decades due to development of 1200 ha of aquaculture ponds. At least 800 ha of ponds on the island were disused as of the start of a four-year project to restore 400 ha at a cost of US$590,000 and initiate adaptive collaborative management. Local communities from six villages willingly made their ponds available for rehabilitation, as their main livelihood had switched to seaweed mariculture and they recognised the urgent need to restore mangrove coverage for fisheries value and storm protection. The initial site restored (43 ha) has naturally recruited to an average density of 2171 stems/ha., 32 months after initial restoration. Three more recent sites have already demonstrated natural recruitment between 767-1450 seedlings within 7-10 months after restoration. Local communities have developed mangrove management groups and regulations for both remnant mangrove forests and rehabilitation areas, which have been acknowledged at higher levels of government. The implementation of gender analyses, gender sensitisation and the development of Womangrove groups have been crucial to ensure the equal involvement of women in the process of mangrove rehabilitation and management. The process of CBEMR at this point is being considered for upscaling and replication, and has been included as a best practice in both the South Sulawesi Provincial and Indonesian National Mangrove Strategies. The CBEMR process has been recommended by the Ministry of Forests - Natural and Protected Forest Management Agency (PHKA) as a requisite practice to restore the 4000 ha in the Tanjung Panjang Nature Reserve in Gorontalo Province, which nearly completely and illegally converted to aquaculture ponds over the past two decades. CBEMR and strategic breaching is also being considered for restoration in Indonesia's largest contiguous converted mangrove forest, which includes 60 000 ha of largely abandoned and disused shrimp ponds in the Mahakam Delta, East Kalimantan. The proven effectiveness of the CBEMR process at small and medium scales relies on its ability to resolve both biophysical and socio-political issues underscoring mangrove forest degradation in Indonesia. If and when this is applied to large-scale restoration, it is sure that continued attention will need to be paid to both biophysical and socio-political approaches.
Scleractinians which have recruited on unstable substrates could function as a source of corals of opportunity' (COP). This study investigated the rearing of juvenile corals of opportunity' in an in situ coral nursery to assist in the rehabilitation of reefs in sedimented environments. Juvenile COPs of Pectinia paeonia (n = 71) and Pachyseris speciosa (n = 45) were collected from coral reefs in Singapore, categorized into three size classes (0.1-1.5, 1.6-3.0, 3.1-4.5 cm) and monitored at an in situ coral nursery for five months. Pectinia paeonia juveniles had higher overall survivorship than P. speciosa (93.0 and 69.6%, respectively) and no significant differences in survivorship among the size classes for either species were observed. The mid-sized and large juveniles of both species grew faster than the small ones. Fortnightly sedimentation and growth rates of all size classes of juveniles were weakly correlated (R < 0.22). The study highlighted the feasibility of rearing juvenile COPs in nurseries as material to supplement reef rehabilitation efforts in locations with high sediment load and unconsolidated substrate.
Conservation outcomes are principally achieved through the protection of intact habitat or the restoration of degraded habitat. Restoration is generally considered a lower priority action than protection because protection is thought to provide superior outcomes, at lower costs, without the time delay required for restoration. Yet while it is broadly accepted that protected intact habitat safeguards more biodiversity and generates greater ecosystem services per unit area than restored habitat, conservation lacks a theory that can coherently compare the relative outcomes of the two actions. We use a dynamic landscape model to integrate these two actions into a unified conservation theory of protection and restoration. Using nonlinear benefit functions, we show that both actions are crucial components of a conservation strategy that seeks to optimise either biodiversity conservation or ecosystem services provision. In contrast to conservation orthodoxy, in some circumstances, restoration should be strongly preferred to protection. The relative priority of protection and restoration depends on their costs and also on the different time lags that are inherent to both protection and restoration. We derive a simple and easy-to-interpret heuristic that integrates these factors into a single equation that applies equally to biodiversity conservation and ecosystem service objectives. We use two examples to illustrate the theory: bird conservation in tropical rainforests and coastal defence provided by mangrove forests.
We attempted to develop practical methods for coral reef rehabilitation, by means of the production of juveniles obtained from sexual reproduction, for a remote island where recruitment is limited. Adult corals (broodstocks) of Acropora tenuis were transported 1100 km from Okinotorishima, Japan's southernmost island in the Pacific, to a hatchery in Okinawa and maintained in land tanks. Eggs were obtained from captive spawning and the resulting larvae and juvenile corals were cultured under laboratory conditions. The present methodology enabled high survivorship and led to the successful mass production of coral juveniles. A total of 564 substrates with similar to 63 000 juvenile corals at the age of 10 mo were transported to the native reef. They were then transplanted in 3 experimental treatments, in order to evaluate effectiveness of protection by cages and/or hiding the juveniles under other substrates. Additionally, the effects of orientation on coral growth were tested by attaching the juveniles face down. The cages effectively protected the corals from predation and nibbling by fishes. The unshaded, upward facing corals in the cages steadily increased their coverage nearly 4-fold in similar to 2 yr.
Coral reefs in Okinawa, Japan, have declined due mostly to human pressures. There are still possiblities to restore coral reefs locally by amelioration or removal of the local chronic stressors. Political support, scientific information, and the will of local stakeholders are crucial for successful amelioration. Development of techniques for restoration by artificial efforts such as underwater silviculture and transplantation are definitely required. Coral propagules for transplantation may be cultured by either of two approaches: asexual or sexual propagation. The rehabilitation of coral reefs by means of asexual propagation is simple and less labour-intensive compared to sexual techniques. However, most of the transplanted pieces share the donors' limited DNA, giving the reef a smaller gene pool. On the other hand, sexual propagation may result in genetically more diverse corals, but is labour-intensive and more expensive. Both techniques require devices for rearing after transplantation. This will become one of the key areas of research in the near future. Some 4-year-old colonies of Acropora tenuis, cultured from eggs and transplanted to the seabed at Akajima, Okinawa, had grown to 20Á25 cm in diameter and initially spawned in June 2009. This indicated the possibility of using this technique to assist local coral reef restoration. Although the small scale of success so far may not be significant, given the wide range of degradation of coral reefs, certain methods of rehabilitation have proved promising enough to continue our endeavour.
Wave energy and storm surges threaten coastal ecology and nearshore infrastructures. Although coastal structures are conventionally constructed to dampen the wave energy, they introduce tremendous damage to the ecology of the coast. To minimize environmental impact, ecofriendly coastal protection schemes should be introduced. In this paper, we discuss an example of an innovative mangrove rehabilitation attempt to restore the endangered mangroves on Carey Island, Malaysia. A submerged detached breakwater system was constructed to dampen the energy of wave and trap the sediments behind the structure. Further, a large number of mangrove seedlings were planted using different techniques. Further, we assess the possibility of success for a future mangrove rehabilitation project at the site in the context of sedimentology, bathymetry, and hydrogeochemistry. The assessment showed an increase in the amount of silt and clay, and the seabed was noticeably elevated. The nutrient concentration, the pH value, and the salinity index demonstrate that the site is conducive in establishing mangrove seedlings. As a result, we conclude that the site is now ready for attempts to rehabilitate the lost mangrove forest.
During an unusual cold‐water event in January 2010, reefs along the Florida Reef Tract suffered extensive coral mortality, especially in shallow reef habitats in close proximity to shore and with connections to coastal bays. The threatened staghorn coral, Acropora cervicornis, is the focus of propagation and restoration activities in Florida and one of the species that exhibited high susceptibility to low temperatures. Complete mortality of wild staghorn colonies was documented at 42.9% of donor sites surveyed after the cold event. Remarkably, 72.7% of sites with complete A. cervicornis mortality had fragments surviving within in situ coral nurseries. Thus, coral nurseries served as repositories for genetic material that would have otherwise been completely lost from donor sites. The location of the coral nurseries at deeper habitats and distanced from shallow nearshore habitats that experienced extreme temperature conditions buffered the impacts of the cold‐water event and preserved essential local genotypes for future Acropora restoration activities.
Sharing experiences and results among scientists and managers working on seagrass restoration was the main objective of the first European Seagrass Restoration Workshop that gathered researchers from around Europe. The meeting was the first forum in Europe that allowed for scientists, NGOs, and managers to interact and share their experiences relating to seagrass restoration and management. The results show that none of the seagrass restoration programs developed in Europe by the participants during the last 10 years was successful. Furthermore, an informal review of data published in seagrass restoration success, showed that the results reported were biased because they were mostly based on a very short monitoring period (i.e. 1 year). Numerous decision trees, guidelines, and restoration models have been developed to aid seagrass restoration management, but the results of this workshop point toward a new paradigm in seagrass restoration were efforts should shift to give priority to natural restoration potential, with an emphasis on the fact that restoration should never be considered the first alternative when planning for the mitigation of coastal development projects or to justify mitigation as a compensation measure for economic activities.
Seagrass restoration has often not been successful due to poor site planning, physical disturbance, transplant timing incompatibility, and physical and biological disturbances. As such, these factors are important for successfully restoring seagrasses, and global success has greatly increased. We conducted restorations in the mid-Atlantic region of the United States to reestablish this valuable habitat. Our restoration efforts in New Jersey involved transplants of both Zostera marina (eelgrass) and Ruppia maritima (widgeon grass). We found that Z. marina site success and transplant survival increased over the scope of this 4-year investigation (66%–100% and 34%–43%, respectively). However, R. maritima success was heavily dependant upon the year planted; with limited success in 2002 (12%) and high success during 2003 (80%), most likely related to the brown-tide bloom and nonbloom associated with these planting years. For both species restored, ecosystem function was becoming established by the end of the study, demonstrated by their ability to trap and bind fine particulate matter. We provide evidence from this study that seagrass restoration is a viable option for coastal managers and that once established, seagrasses can recover and expand.
Mangrove ecosystems are important coastal habitats in tropical regions, directly or indirectly supporting subsistence and commercial fisheries. However, they are under threat in developing countries, where stands are being felled to accommodate a variety of human activities. An estimated aerial loss of 1% per year is occurring in Asia and the Pacific, with some areas having lost 70% of their original mangrove habitat. Due to continued disturbance, altered soil conditions and limited dispersal, natural recovery may be slow. This paper discusses mangrove restoration as a potential tool for the management of coastal ecosystems. We examine briefly the connections between mangroves and fisheries, and outline an ecosystem approach to evaluate mangrove restoration initiatives. Past mangrove restoration projects in developing countries have focussed only on methods of re-establishing trees, with little attention given to assessing whether ecosystem function is restored. However, the goal of mangrove restoration projects should be to actively promote a return to the natural assemblage structure and function (within the bounds of natural variation) that is self-sustaining. This goal requires: (i) identifying the natural state, including key organisms in maintaining the physical substratum, community structure and food webs maintaining fish stocks; (ii) developing biotechnology for restoring key organisms; and (iii) assessing the long-term success of the project. As restoration promises to be an important tool for maintaining coastal ecosystem health in developing countries, priority should be given to incorporating restoration projects and their evaluation into coastal management plans.
Marine vegetated habitats (seagrasses, salt-marshes, macroalgae and
mangroves) occupy 0.2% of the ocean surface, but contribute 50% of
carbon burial in marine sediments. Their canopies dissipate wave energy
and high burial rates raise the seafloor, buffering the impacts of
rising sea level and wave action that are associated with climate
change. The loss of a third of the global cover of these ecosystems
involves a loss of CO2 sinks and the emission of 1 Pg
CO2 annually. The conservation, restoration and use of
vegetated coastal habitats in eco-engineering solutions for coastal
protection provide a promising strategy, delivering significant capacity
for climate change mitigation and adaption.
For degraded coral reef systems with limited larval supply, active restoration techniques may provide a means of replenishing adult coral populations. Settling or seeding large numbers of sexually-produced larvae directly onto denuded substrate is a potential restoration tool that can eliminate the costs associated with rearing coral spat in culturing facilities. However, the long-term potential to enhance recruitment using seeding techniques has generally been limited due to high post-settlement mortality. Using the brooding coral Porites astreoides (Lamarck, 1816), we explored two potential strategies—choosing favorable substrate communities and caging recently settled spat—to enhance early post-settlement survival during seeding efforts. Larvae were collected from adult colonies in the laboratory and, once competent to settle, were seeded directly onto the reef substrate. Settled spat were individually mapped and monitored using fluorescence techniques, and found to have a low survivorship with <3%–15% surviving after 1 mo, and <1% after 5 mo. Techniques to enhance survival, including choice of substrate and post-settlement caging, did not significantly influence the high rates of natural mortality. These results underscore the general lack of knowledge regarding the major factors that drive the magnitude of early post-settlement mortality, and future identification of these mortality factors may lead to suitable techniques to enhance survival in seeding efforts.
Sexual propagation of corals specifically for reef rehabilitation remains largely experimental. In this study, we refined low technology culture and transplanta-tion approaches and assessed the role of colony size and age, at time of transfer from nursery to reef, on subsequent survival. Larvae from Acropora millepora were reared from gametes and settled on engineered substrates, called coral plug-ins, that were designed to simplify transplanta-tion to areas of degraded reef. Plug-ins, with laboratory spawned and settled coral recruits attached, were main-tained in nurseries until they were at least 7 months old before being transplanted to replicate coral limestone out-crops within a marine protected area until they were 31 months old. Survival rates of transplanted corals that remained at the protected in situ nursery the longest were 3.9–5.6 times higher than corals transplanted to the reef earlier, demonstrating that an intermediate ocean nursery stage is critical in the sexual propagation of corals for reef rehabilitation. 3 years post-settlement, colonies were reproductively mature, making this one of few published studies to date to rear a broadcasting scleractinian from eggs to spawning adults. While our data show that it is technically feasible to transplant sexually propagated cor-als and rear them until maturity, producing a single 2.5-year-old coral on the reef cost at least US$60. 'What if' scenarios indicate that the cost per transplantable coral could be reduced by almost 80 %, nevertheless, it is likely that the high cost per coral using sexual propagation methods would constrain delivery of new corals to rela-tively small scales in many countries with coral reefs.
Native oyster reefs once dominated many estuaries, ecologically and economically. Centuries of resource extraction exacerbated by coastal degradation have pushed oyster reefs to the brink of functional extinction worldwide. We examined the condition of oyster reefs across 144 bays and 44 ecoregions; our comparisons of past with present abundances indicate that more than 90% of them have been lost in bays (70%) and ecoregions (63%). In many bays, more than 99% of oyster reefs have been lost and are functionally extinct. Overall, we estimate that 85% of oyster reefs have been lost globally. Most of the world's remaining wild capture of native oysters (> 75%) comes from just five ecoregions in North America, yet the condition of reefs in these ecoregions is poor at best, except in the Gulf of Mexico. We identify many cost-effective solutions for conservation, restoration, and the management of fisheries and nonnative species that could reverse these oyster losses and restore reef ecosystem services.
PlantingSpartina patens (Salt Meadow Cord Grass) is an integral part of restoring salt marshes along Tampa Bay, Florida, USA. Of the salt marsh species that are planted,S. patens often has the lowest survivorship. State managers have hypothesized that this low survivorship is related to transplant shock and to acidic soil conditions commonly found under dense stands ofCasuarina sp. (Australian Pine), an exotic invasive. This study documents plantedS. patens health and survivorship over 11 months at a restoration site previously dominated byCasuarina sp. Three plots of 100 plants each were established in varying soil pH, with each plot covering above and below the recommended elevation range forS. patens. Transplant shock occurred within the first thirty days after planting and affected overall survival.Spartina patens survival was not affected by soil pH (p=0.827) as evidenced by the presence of healthy individuals outside the plots, in soil pH ranging from 4.76 to 8.94. However, there was a sharp decline in plant health when redox potentials fell below −50 mV. Although elevation and redox potential were highly correlated (p<0.001, R2=0.736), plant health varied more with elevation (p<0.001, R2=0.387) than redox potential (p<0.001, R2=0.950), suggesting that elevation, while a good coarse predictor of site suitability, may not always be the best measure. Redox potential should be monitored, in addition to measuring elevation, to avoid planting in highly reduced areas. Furthermore, adjusting the lower limit of the target elevation range to a higher elevation will increase the amount of survivorship.
JFE Steel has developed restoration technology of damaged coral reefs using carbonated block, "Marine BlockTM." In Miyakojima in Okinawa Prefecture, the transplanted larva coral on "Marine BlockTM" had spawned eggs, and it was proved that this technology is well suited to coral reef restoration. Furthermore, this technology is currently on-site evaluation in the Republic of Indonesia, and the progress of this experimental project will be introduced in this paper.
Environmental or biodiversity offset policies allow for impacts occurring at one site to be offset through activities at another site. The federal government has recently released a policy for offsetting the impacts of activities approved under the Environment Protection and Biodiversity Conservation Act 1999 (Cth) (EPBC Act). The EPBC Act policy can be used to offset impacts on terrestrial and marine ecosystems, and one of the first applications of the policy has been to offset impacts on seagrass meadows at risk due to the Abbot Point coal terminal expansion.The significant ecological differences between terrestrial and marine ecosystems, such as seagrass meadows, require different management approaches to ensure that impacts are offset. This article analyses the EPBC Act policy to determine whether it adequately caters for offsetting impacts on marine ecosystems, with seagrass used as an example. It concludes with recommendations for policy change directed at ensuring that the unique characteristics of seagrass ecosystems are considered in offset policies.
Efforts to restore the native oyster in the Chesapeake Bay enjoy enormous public support and have consumed and continue to consume vast, some would argue unreasonable and unjustifiable, amounts of funding. Despite this support the stated goals of restoration efforts are poorly defined and consequently provide no realistic measures of success in terms of time, space, or biomass. Quantitative approaches used successfully in management of and rebuilding plans for other marine and estuarine species have not been appropriately applied. Basic information in oyster population dynamics and ecology has been inadequately appreciated in defining the quantitative problem. Given these limitations it is not surprising that little success has been achieved despite the massive investment. We note a lack of ability to predict recruitment, and limit the ingress and impact of disease. Without control of both of these functions, populations cannot be managed in a self-sustaining rebuilding mode within the footprint that they either currently occupy or formerly occupied. Sustained expansion of that footprint through substrate provision is prohibitively expensive, beyond the limits set by availability of substrate material, and futile in the presence of disease and susceptible oysters. Without attaining a substantially increased and rebuilding population, ecological services will be limited. Water quality impacts will, in reality, be modest, local and seasonal, and still subject to being overwhelmed by periodic storm events. Coherent and rational evaluation of biological limitations will lead to more realistic, and indeed very modest goals for ecological restoration. We must accept the fact that efforts to date to restore native oyster populations have failed and the prognosis for improvement of this situation is continued failure. The argument is proffered that stabilizing the present bed footprint with a realistic and sustainable population and the promotion of aquaculture to increase commercial yield is a more predictable and stable economic investment. Each of these options is consistent with the most realistic ecological outcome and should take priority in future efforts.
The Hudson River estuary (HRE) had significant populations of eastern oysters (Crassostrea virginica) prior to the 1920s. A combination of overfishing, pollution, and habitat destruction led to the loss of both the oyster fishery and the ecological services oysters provide. Recent improvements in water quality have led to an interest in reintroducing eastern oysters into the HRE to enhance ecosystem characteristics. However, there are few data on oyster biology and the potential for their restoration in the HRE. In this study, we measured growth, reproduction, and survival of oysters transplanted to two sites in Jamaica Bay (New York) with contrasting water-quality parameters. Condition index and gonadal stage were measured in adult oysters from May through August 2003. Juvenile growth and mortality were measured from July to October 2003. These measurements provide the first description of oyster growth, survival, and reproduction in the HRE. We found that adult oysters successfully spawn in Jamaica Bay, and their gonadal maturation is similar to that of oysters in Long Island Sound. Juvenile growth, measured as shell height (mm), was comparable to that of oysters in other local marine systems and was not affected by the reduced water quality in Jamaica Bay. These preliminary data can guide restoration planning. However, we suggest that several issues need further research before restoration efforts are implemented in the HRE.
The Laguna Madre in Corpus Christi, Texas has a great deal of petroleum and natural gas activity while housing a national seashore. The area is a flyway for a wide array of bird species, as well as heavily fished. Historically, the laguna had a series of infrastructure modifications, gas and oil rigs, and real estate development. In the process of placing a drilling rig, a winter storm blew the vessel with the rig off a narrow channel. To remove the vessel, other vessels had to be called. A 35-acre accident occurred. In mitigation, 75 acres of the seagrass Halodule wrightii was planted in three areas: (1) a 15-acre dredge island where a portion of the island was scraped down from upland-spoil deposit to −2 ft mlw; (2) a mile-long channel where seagrasses were restored from −7 to 10 ft mlw to −3 to ft mlw; and (3) a persistently barren site for decades (scraped by another petroleum company's vessel) was restored in the shallows while holes were filled in and seagrass planted on top. The fill throughout was from the scraping from the dredge islands. The fill was transmitted several miles by a new device. Planting of Halodule plugs proceeded from March to July 1999. Within 3 months, the shallow sites had been covered with the restored Halodule,. Endangered species of roseate spoonbills, brown pelicans, great white herons and other wading and fishing birds were regularly feeding at two sites. The deeper sites had heavy fish populations return to the area, fished by man, seagulls and pelicans. Despite a direct hit by Hurricane Bret in 1999, lateral growth at all depths was deemed governmentally satisfactory. This same procedure with seagrasses is recommended for after-effects of estuarine oil spill cleanup, and mitigation banks of seagrasses are recommended for construction or operations mitigation.
Heavy losses of 6200 ha of seagrass off the Adelaide metropolitan coast since 1949 have had substantial implications for beach management, fisheries and biodiversity. Here, we describe for managers some promising initial trials to develop a cost-effective method to rehabilitate some of these lost seagrasses.
Many conservation organizations use spatial prioritization to help identify locations in which to work. Increasingly, prioritizations seek to account for spatial heterogeneity in the costs of conservation, motivated in part by claims of large efficiency savings when these costs are included. I critically review the cost estimates on which such claims are based, focusing on acquisition and management costs associated with terrestrial protected areas. If researchers are to evaluate how including costs affects conservation planning outcomes, estimation methods need to preserve the covariation between and relative variation within costs and benefits of conservation activities. However, widely used methods for estimating costs and incorporating them into prioritizations may not meet these standards. For example, among relevant studies, there is surprisingly little attention given to the costs that conservation organizations actually face. Instead, there is a heavy reliance on untested proxies for conservation costs. Analytical shortcuts are also common. Now that debate is moving beyond whether to account for costs in conservation planning, it is time to evaluate just how we can include them to greatest effect.
Worldwide, 29% of seagrass habitats have been lost over the past century. Compared with large-scale losses, successful restoration programs are usually only small scale (a few hectares). One area of significant seagrass loss (45200 ha) is Adelaide, South Australia. Improvements to wastewater management have raised the possibility of rehabilitation in this area. Traditional methods of seagrass restoration are expensive and have had limited success owing to high wave energy. We investigated a range of biodegradable substrates, mostly made of hessian (burlap), to enhance Amphibolis recruitment as an alternative. After 5 weeks, 16 514 seedlings, or 157 seedlings m(-2), had recruited. Survival declined over the following 12 months to 31.4%, and down to 7.2% after 3 years, in part as a result of breakdown of the hessian, and the wave-exposed nature of the sites. During the initial 12 months, above- and belowground biomass increased 2.6- and 6.4-fold, respectively. The technique may represent a non-destructive, cost-effective (<AU $10 000 ha(-1)) method to restore Amphibolis over large spatial scales and in areas that are hydrodynamically too active for traditional techniques, thus helping ameliorate some of the large-scale losses of seagrasses that have occurred globally.
Facing the worldwide coral degradation, active restorations are moving toward improving techniques to maintain coral coverage. Transplant methods have been used to restore coral reef areas that were completely degraded; however restoration is not commonly employed at coral reefs with evident loss that may jeopardize the maintenance of the community. In this study the re-attachment concept using the natural fragmentation of branched-corals was tested as an accelerator process to natural recovery based on asexual reproduction. Survivorship, growth and attachment rates of three Pocillopora species on both natural and artificial substrates were evaluated at four sites of Islas Marietas. Over one year of monitoring during 2012–2013, resulted in a high survivorship of 87% on artificial underwater structures and 67% on natural substrate, the height and radial growth, on both substrata increase 2-fold from the initial size; although both substrata were viable, coral fragments attach faster on natural (4 months) than artificial structures (6 months). The results demonstrate that re-attachment using natural substrata is a potential and no invasive instrument for treating coral reefs not completely degraded in restoration programs.
The importance of judging success of restoration studies over extended time periods has been repeatedly voiced but convincing information to justify increased monitoring is generally unavailable. Building on Bell et al. (2008), we investigated the development of areal coverage of the seagrass, Halodule wrightii, as a metric for assessing the outcome of a restoration effort conducted near Tampa Bay, Florida, U.S.A., over 7 years, thereby expanding the timescale over which a subtropical seagrass restoration project was evaluated for success. In each of 12 plots, 500 planting units of H. wrightii were introduced in 2002, and the seagrass cover level documented annually through 2009. Although only low-moderate levels of H. wrightii cover were recorded after 3 years, a rapid increase to high coverage levels was evident in many plots after 2006 and sustained through 2009. Plots that supported only low levels of seagrass cover initially remained poor performers, 4–7 years post-planting. By 2008, substantial seagrass spillover, contiguous with over 75% of plots, was recorded. When both within-plot coverage and spillover were considered, seagrass restoration success was attained 6 years after initiation. Our findings provide an example of comparatively longer-term monitoring of a restoration effort leading to reversal of an earlier evaluation of project success. Moreover, unique information on H. wrightii temporal dynamics emerged from the 7 year study, further illustrating the value of long-term assessment of restoration. Extending the duration of post-planting surveys of seagrass coverage may address multiple needs as it advances the field of seagrass restoration.
Serious degradation of coral reefs in the Co To Archipelago occurred
from 2002 to 2006. Nearly 80% of the species and over 90% of living
coral cover were lost and some reefs were completely dead. Currently,
the highest coral cover is only 7.5% where previously most of the reefs
had over 50% live coral cover. The cause of the reef degradation has
been identified to be residues of cyanide used by local fishermen for
fishing on reefs. To overcome the consequences transplantation corals on
natural and artificial shelters were attempted. Survival rate on
artificial shelters was 88.3% after 2 years and growth rate averaged 2.3
cm/year. Transplanted corals on natural shelters had lower survival
rate, 55.9%. The natural recovery of coral on degraded reefs was also
monitored periodically in this study. No coral recruitment was seen on
completely dead reefs whereas there was little new coral recruitment on
reefs with some remaining live corals.
Seagrasses and the valuable ecosystem services they provide are threatened world‐wide by impacts of human activity. Numerous revegetation efforts have attempted to restore seagrasses. Most restoration programmes use plants collected from the field because of limited seed availability, low seedling survival and difficulty in culturing plants. However, this practice risks damage to donor populations and has the potential to reduce genetic diversity, which may counteract the desired effects of restoration.
A novel aquaculture system for producing plants (mother plants and cuttings) from a limited number of seeds was tested using Cymodocea nodosa as model species. The ability of transplanted cuttings to survive and grow in the natural habitat was also evaluated.
Seed germination was high (48%) compared with field conditions, and most seedlings produced mother plants with up to 7·8 m of rhizome and 300 shoots within 4 years in culture. All cuttings from mother plants regenerated new plants. Up to 100 transplants were produced from two seeds, and most (85%) of them survived and initiated the colonization of substrate, 1 year after planting.
Synthesis and applications . This study provides a robust protocol that can reduce plant and/or seed collection pressure on donor populations and produce a high number of transplants which show lower mortality rates during the early transplantation phases. This method can also help to preserve genetic diversity in restored populations, which should be one of the major goals of ecological restoration. This novel tool can be applied to other seagrass species with low or unpredictable reproductive success, therefore the development of nurseries should be incorporated in future restoration programmes. This is currently the only sustainable methodology to produce material for transplanting programmes for protected species.
In concept, ecological restoration will improve ecosystem characteristics of degraded habitats, but in practice, restoration success assessments typically target vegetation communities. We sought to determine if estuarine emergent marsh restoration projects (Galveston Bay, Texas) that had successfully achieved permit-mandated plant coverage were comparable to reference sites at an ecosystem level. We used a Rapid Assessment Method developed specifically for this habitat (Galv-RAM) to compare restored (ages 5–15 y) and reference marshes. Thirteen biotic and abiotic characteristics were used to calculate an ecosystem index score, whereby a pristine habitat would score 100%. The average Galv-RAM ecosystem index score for reference marshes (81%) was typical for urbanized estuaries. Restored marshes scored 75%, indicating that they were relatively well developed, although there was substantial variability in ecosystem index scores among sites. Discriminant function analysis revealed that reference sites had more benthic epifauna (periwinkles, fiddler crabs); epifauna were virtually absent from restored sites. Overall, Galv-RAM scores did not vary with restored marsh age, but some individual features changed over time: older restored sites tended to have higher plant diversity and belowground plant biomass than younger restored sites. The ultimate goal of coastal wetland restoration is to improve the integrity of the regional wetland landscape by augmenting many different ecosystem functions. Therefore, although not all measured variables scored optimally in all restored sites, each of the sites had relatively high ecological value and contributed to the integrity of a large scale matrix of wetland habitat.
Sediment fertilization is recommended for improving seagrass restoration efforts, but few studies have evaluated the efficacy of such practice. Increasing storm frequency due to global change could lead to greater sediment mobilization. Understanding how this alteration will interact with fertilization to affect transplants is essential for future restoration planning. We examined the individual and combined effects of nutrients (ambient vs. repeated addition) and burial (control vs. increased frequency and intensity) on the performance and biomass partitioning of transplants of the seagrass Cymodocea nodosa at two sites within a north-western Mediterranean meadow. Fertilization stimulated the production of shoots, total biomass, and branching. Burial increased leaf sheath length in one site while reduced shoot number, leaf number, leaf sheath length, total biomass, net shoot gain, and root-to-shoot ratio in the other site. Regardless of the site, fertilization and burial interaction reduced the length of vertical internodes and horizontal rhizomes, and the net shoot gain. Our research demonstrates that sediment fertilization ensures rapid colonization of restoration sites, providing C. nodosa plants up to eight times larger than controls in one growing season. However, it also indicates that interaction of increased burial and nutrients reduced the gain in terms of vegetative expansion and depressed vertical growth, making plants more vulnerable to subsequent disturbances. Therefore, seagrass restoration practitioners should account for changes in sediment elevation at transplanting sites when planning restoration programs and carefully evaluate the opportunity of applying fertilizers in sites subjected to greater sediment accumulation to avoid failure.
The success of urban salt marsh restoration depends upon an understanding of the local tidal regime and hydrologic conditions. Reference wetland characteristics can provide biological and physical restoration baselines for a restoration design through the use of techniques such as bio-benchmarking and geomorphologic assessment. Reference site vegetation can be used as indirect indicators of local tidal elevations and duration of flooding of each tidal zone. Reference sites can also provide landscape allometry to generate geomorphologic ratios that can be applied to the restoration site. Through the use of field measurements, aerial photographs, and GIS technology, relationships can be identified for tidal channel width, depth, diurnal tidal prism, and marsh area. Calculating a hydrologic budget for freshwater is critical to estimate salinity concentrations and their effect on the restoration wetland. This information, along with field measurements of salinity, can be used to predict salinity ranges resulting from the interaction of freshwater sources and will help determine the target vegetation communities. Preconstruction planning is not always sufficient to understand site conditions, especially in urban areas. Flexibility in design, even during the construction phase, may be required to assure project success. During excavation of fill, conditions were found at specific locations that would reduce the likelihood of reestablishing historic functions and values of the tidal marsh. Designs were altered at one low marsh area, which was redesigned as mudflat; and a second low marsh area that was changed to a freshwater fen.
Environmental Practice 14:1–11 (2012)
Mangroves are species of halophytic intertidal trees and shrubs derived from tropical genera and are likely delimited in latitudinal range by varying sensitivity to cold. There is now sufficient evidence that mangrove species have proliferated at or near their poleward limits on at least five continents over the past half century, at the expense of salt marsh. Avicennia is the most cold-tolerant genus worldwide, and is the subject of most of the observed changes. Avicennia germinans has extended in range along the US Atlantic coast and expanded into salt marsh as a consequence of lower frost frequency and intensity in the southern USA. The genus has also expanded into salt marsh at its southern limit in Peru, and on the Pacific coast of Mexico. Mangroves of several species have expanded in extent and replaced salt marsh where protected within mangrove reserves in Guangdong Province. In south-eastern Australia, the expansion of Avicennia marina into salt marshes is now well documented, and Rhizophora stylosa has extended its range southward, while showing strong population growth within estuaries along its southern limits in northern New South Wales. Avicennia marina has extended its range southwards in South Africa. The changes are consistent with the pole-ward extension of temperature thresholds co-incident with sea-level rise, although the specific mechanism of range extension might be complicated by limitations on dispersal or other factors. The shift from salt marsh to mangrove dominance on subtropical and temperate shorelines has important implications for ecological structure, function, and global change adaptation. This article is protected by copyright. All rights reserved.