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Mosaic of Landsat TM5 image, band 4, from path/rows 219/77 and 220/77, with focus on mangrove areas (white).
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The current paper examines the growth and spatio-temporal variation of mangrove forests in response to depositional processes and different salinity conditions. Data from mangrove vegetation structure collected at permanent plots and satellite images were used. In the northern sector important environmental changes occurred due to an artificial cha...
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... current paper examines the growth and spatio-temporal variation of mangrove forests in response to depositional process and different salinity conditions. Two distinct areas in the Cananéia-Iguape Coastal System, SE Brazil, were assessed using data from time-series satellite Landsat images and monitored vegetation structure in permanent plots. The Cananéia-Iguape Coastal System (CICS), SE Brazil, consists of a complex of lagoon channels (Figure 1), and is part of a World Heritage site by UNESCO, with criteria (vii)(ix)(x), since 1999. The CICS can be divided in two sectors, the northern and the southern, based on geomorphology and environmental conditions. In the northern sector, important environmental changes occurred over the last 150 years due to the opening of an artificial channel. This artificial channel (Valo Grande), which connects the Ribeira River to the coastal system, produced significant modifications in salinity, depositional patterns and input of heavy metals resulting from lead mining activities into the system, although these ceased in 1995 (Mahiques et al ., 2009). The southern sector, which is less influenced by the low salinity of the artificial channel, is considered the best conserved mangrove area along the coast of the State of São Paulo. To provide current mangrove area estimations in the coastal system, polygons were obtained from the Atlas website of SOS Mata Atlântica and INPE (2010). Based on our field expertise in the area since 1999, and QuickBird and IKONOS high-resolution images available in Google Earth, the polygons were modified and new areas were delineated using visual interpretation. Landsat TM5 images from 1997 and 2010 were processed using SPRING (Câmara et al ., 1996), version 5.1.6, a Geographic Information Processing System developed and freely distributed by the National Institute for Space Research (INPE - Brazil). Colour compositions 2B3R4G were used in digital processing techniques, including segmentation by region growing, and Battacharya supervised classification complemented by visual interpretation and ground truth to map mangrove areas in both periods and sectors. The characterisation of structure forest development followed the methodology suggested by Cintrón and Schaeffer-Novelli (1984). Within five transects located along the depositional gradient, 26 permanent plots were established, which varied between 4m 2 to 150m 2 , according to stem density. New permanent plots were placed when new mangrove stands, with a minimum of 20 individuals, of 1 meter height or more, colonized depositional areas. In each plot, all plants were identified and tree diameter, height, and incidence of associated species were recorded. Mean height, basal area dominance, and stem density were also assessed. In the southern sector, mangrove stands were monitored in January 2001, November 2004, July 2008 and July 2010, whereas in the northern sector, the mangrove forest vegetation structure was described in July 2010. Cluster analysis (UPGMA), using Statistica software version 7.0, was applied to the data from January 2001 and July 2010, using parameters for mean height and log-transformed tree density values, originated from permanent plots located in the southern sector. The area was here estimated as equal to 15,193ha based on the proposed methodology (Figure 2). The map highlighted the southern sector sheltering higher mangrove areas, as result of a larger number of lagoon channels, rivers and creeks. The literature reports smaller areas of mangrove ecosystems, such as 13,751ha from SOS Mata Atlântica and INPE (2010) and 7,200ha from Herz (1991). The main accurate focus on mangrove areas, the knowledge of this coastline, distinct studied periods, or changes in the ecosystem could be the reasons of the disparity between the literature and our ...
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Mangrove forests are intertidal wetland with a diverse assemblage of trees, shrubs and palms growing along tropical and subtropical coastlines. Effective mapping of mangrove forests has not yet been achieved due to the periodicity of tidal dynamics. Our previous studies showed that a submerged mangrove recognition index (SMRI), which was proposed b...
The Population of Karachi metropolitan city is increasing at a rapid rate, therefore demand for drinking water day by day. This demand requires permanent fresh water supply for the residential areas. Consequently, desalination plants are needed on the coastal belt of the city on a priority basis. Desalination plants can potentially be harmful by th...
Mangrove forest ecosystems are known to sequester large quantities of carbon in biomass. This paper presents a quantification of carbon stocks in aboveground (standing trees, palm, shrub, standing dead trees, downed wood, and litter), belowground (root), and total carbon stocks, and further compared between forest types (fringe and riverine) and zo...
Citations
... This initiative was taken in 1992 by the National Land Council and Forestry Council [74]. For a productive forest like the MMFR, management mostly rests on the supply and demand, and poor management decisions are frequently originated on poor or fragmented pieces of evidence [75]. In some cases, it has also been observed that the mangrove forest has been harvested before the rotation period. ...
Mangrove ecosystems are crucial for biodiversity and coastal protection but face threats from climate change and human activities. This review assesses the productivity of the Matang Mangrove Forest Reserve (MMFR) in Malaysia, which is recognised as one of the best-managed mangrove forests, while also addressing challenges such as deforestation and climate change-induced factors. This review explores the concept of productivity in mangrove forests, highlighting their role in carbon sequestration and discussing litterfall measurements as fundamental metrics for assessing primary productivity. An analysis of historical changes in MMFR’s biomass and productivity revealed fluctuations influenced by logging, reforestation, and climatic conditions. Trends in MMFR productivity indicate a concerning decline attributed to anthropogenic activities such as aquaculture and industrial projects. A regression analysis conducted on Rhizophora apiculata data with age as the predictor and AGB as the response variable indicated a positive trend (slope = 3.61, R-squared = 0.686), suggesting a quantitative increase in AGB with age. Further analysis revealed a significant negative trend in MMFR’s overall productivity over years (coefficient = −3.974, p < 0.05) with a strong inverse relationship (rho = −0.818, p < 0.05), indicating declining AGB trends. Despite these challenges, this review underscores the significance of sustainable management practices, effective conservation efforts, and community engagement in maintaining mangrove ecosystem health and productivity. In conclusion, sharing management lessons from MMFR can contribute to global conservation and sustainable mangrove forest management efforts, fostering resilience in these vital ecosystems.
... The width of the channel increased from 4.4 m to 250 m in just a few decades [25]. Despite the region's conservation, studies have identified clearings in mangrove areas in the Iguape region due to the increase in invasive aquatic macrophytes in this sector that resulted from the opening of the Valo Grande canal [26]. In the northern section, microclimatic monitoring of mangroves has been occurring, with variations interpreted as an indicator of changes in mangrove structure at its edge and inside the ecosystem [27,28]. ...
Citation: Lima, N.; Cunha-Lignon, M.; Martins, A.; Armani, G.; Galvani, E. Impacts of Extreme Weather Event in Southeast Brazilian Mangrove Forest. Abstract: Climate oscillations are becoming more extreme, and mangroves may be more susceptible to changes in physical conditions that can lead to mass diebacks. The current study analysed the impacts of an extreme weather event in the Cananéia-Iguape Coastal System, southeast Brazilian mangroves and the condition of the area over three years. We used a multiproxy approach, including analyses of climatic attributes, structural vegetation, and vegetation indices. Damage caused by a strong storm and hail damage had a severe impact on mangrove areas. A meteorological station installed in the mangrove since 2008 recorded a maximum wind gust of 58 km·h −1 on 30 May 2019. On the Beaufort scale, this speed is classified as strong wind. After the extreme weather event, there were catastrophic impacts on the mangrove, with more than 90% dead trunks. Vegetation indices were reduced, indicating intense changes. The NDVI of the mangroves was reduced from 0.72 to 0.35. The LAI confirmed this premise, with a reduction from 4.25 to 0.63. After three years, natural recovery had not occurred. Extreme weather events have continued to occur along coasts, drastically altering the landscape. Mangroves have been affected by these events, and depending on the state of health of the forests, may have difficulties in recovery.
... In 1997, the salt marshes and mangroves of the ELCCI in the vicinity of Valo Grande appeared to be in a good state of conservation (Cunha-Lignon et al. 2011, 2015. Although the exact initial establishment year of AMs is unknown (Sampaio et al. 2021a), in the late 2000s, AMs was established as floating banks in the margins of and within mangroves, and the death of mangrove trees accelerated (e.g., Cunha-Lignon et al. 2011;Cunha-Lignon et al. 2015; note historical Google Earth Pro images). ...
... In 1997, the salt marshes and mangroves of the ELCCI in the vicinity of Valo Grande appeared to be in a good state of conservation (Cunha-Lignon et al. 2011, 2015. Although the exact initial establishment year of AMs is unknown (Sampaio et al. 2021a), in the late 2000s, AMs was established as floating banks in the margins of and within mangroves, and the death of mangrove trees accelerated (e.g., Cunha-Lignon et al. 2011;Cunha-Lignon et al. 2015; note historical Google Earth Pro images). The low salinity was identified as the primary cause of this transformation (Cunha-Lignon et al. 2011;Sampaio et al. 2021a). ...
... Although the exact initial establishment year of AMs is unknown (Sampaio et al. 2021a), in the late 2000s, AMs was established as floating banks in the margins of and within mangroves, and the death of mangrove trees accelerated (e.g., Cunha-Lignon et al. 2011;Cunha-Lignon et al. 2015; note historical Google Earth Pro images). The low salinity was identified as the primary cause of this transformation (Cunha-Lignon et al. 2011;Sampaio et al. 2021a). Recently, among the substances transported into the ELCCI by the Ribeira de Iguape River, such as heavy metals, organic compounds, and inorganic nutrients (Mahiques et al. 2009(Mahiques et al. , 2013Reis et al. 2019), the nitrates (NO 3 -), coming from agricultural activities and upstream sewage, has also been highlighted as a major factor in the spread of AMs and death of mangrove trees (Reis et al. 2019;Sampaio et al. 2021a, b). ...
The Cananéia-Iguape estuarine-lagoon complex (ELCCI) in southeastern Brazil has been affected by the death of mangrove trees and the establishment of aquatic macrophytes (AMs). The main causes suggested for this phenomenon are reduced salinity and high nitrate concentrations; however, the possibility of a cause-and-effect relationship involving vegetation has also been raised. Aiming to enrich discussions about the catastrophic fate of the ELCCI, this study reviews the vegetation dynamics of the region proposed by Sampaio and colleagues and presents additional potential causes, effects, and conservation alternatives. We studied the ELCCI’s vegetation in 2000 and 2015 and analyzed orbital images produced in 2002–2022. We verified the death of mangroves and the invasion of 34 AMs within the mangroves and forming floating banks from the mid-2000s onward. The majority of AM species are native, and have low or no capacity to directly kill mangrove trees. We propose that the establishment of AMs and the death of mangroves in the ELCCI could be caused by an increased influx of freshwater enhancing AMs’ competitiveness and inducing vegetation replacement, or by an initial death of mangrove by some unknown factor (regressive ecological succession) followed by the entrance of AMs (progressive ecological succession). We suggest management actions to reduce freshwater input to increase salinity, since direct vegetation management is impractical.
... Water circulation in the channels is driven by tides (mean semidiurnal amplitude: 0.82 m; Mahiques et al. 2009) and variable seasonal inflow of freshwater from continental drainage of several rivers (Mahiques et al. 2009). The adjacent mangrove forest is primarily dominated by the smooth cordgrass Spartina alterniflora and the mangrove species Rhizophora mangle, Laguncularia acemose and Avicennia schaueriana (Cunha-Lignon et al. 2011). In contrast to Cananéia, the Bertioga system is located near the industrial Baixada Santista Metropolitan Region, where largescale petrochemical industry, port activities and urban areas exert a large pressure on the coast. ...
Microbial dinitrogen (N 2 ) fixation and intense bioturbation by macrofauna can contribute to reduce nitrogen (N) limitation in mangrove systems. In particular, crabs are important ecosystem engineers that rework sediments, redistribute organic matter, accelerate nutrient cycling and shape microbial communities in mangrove sediments. Hosting functionally diverse microbial communities, crabs form a discrete ecological unit (a holobiont). In this study, we report rates of respiration, inorganic N fluxes, net N 2 fixation, denitrification and dissimilatory nitrate reduction to ammonium (DNRA) measured in the fiddler crab Leptuca thayeri and sesarmid crab Armases rubripes holobionts, which are dominant in oligotrophic and eutrophic mangrove systems of southeast Brazil, respectively. We measured lower biomass-specific rates of respiration and ammonium (NH 4 ⁺ ) production for the larger L. thayeri compared to A. rubripes , with very different molar ratios of O 2 respiration to NH 4 ⁺ production (152:1 vs. 20:1, respectively). This suggests a size-metabolism relationship, different food quality or different coupling of N excretion and assimilation by the crab holobionts in the 2 systems. Both crab holobionts contributed to net denitrification and DNRA, with faster N cycling in A. rubripes in the eutrophic system. Net N 2 fixation was also detected, with nearly 4-fold higher rates in A. rubripes compared to L. thayeri . Overall, our results illustrate active and complex N cycling associated with the 2 dominant crab holobionts and highlight their potential and overlooked role as important conduits of fixed N, which may double N 2 fixation rates in the mangrove’s rhizosphere.
... A dinâmica da vegetacaõ de mangue pode modificar-se atraveś do tempo, com as mudancas na quantidade de inundações marinhas por mudanças no uso e ocupacaõ de uma determinada bacia e influxo de água doce proveniente dos rios, sendo excelentes bioindicadores, pois respondem aos gradientes de inundacaõ, de nutrientes e de salinidade (SCHAEFFER-NOVELLI; VALE; CINTROŃ, 2015). Tal heterogeneidade parece ser uma resposta à interacaõ de vaŕios fatores abioticos e antroṕicos que atuam em diferentes escalas locais e/ou regionais (microescala e mesoescala) e temporais (BERNINI; REZENDE, 2010;CUNHA-LIGNON et al., 2011). ...
... A vegetacaõ apresenta baixa diversidade, uma vez que poucas espećies conseguem se adaptar às oscilações da maré e salinidade, ao substrato inconsolidado e pouco oxigenado (CUNHA-LIGNON et al., 2011;LONDE et al., 2013;TOGNELLA, 2014). Nos manguezais brasileiros, ocorrem treŝ generos: Rhizophora L., Laguncularia C.F. e Gaertne Avicennia L., com um total de seis espećies: Rhizophoramangle L. Sergipe (SANTOS, 2013). ...
Os manguezais são ecossistemas costeiros comuns em regiões de clima tropical e subtropical e sujeitos ao regime de marés e à conexão de ambientes de água doce e marinhos, podendo ser encontrados em quase toda a costa brasileira (04°30’N; 28°28’S), o que representa cerca de 8,9% dos manguezais do mundo. Por suas características únicas, são considerados excelentes indicadores de mudanças climáticas. Em Alagoas e Sergipe, os manguezais ocorrem em todas as áreas estuarinas, rios e canais com conexões aos corpos d’água das principais
lagoas costeiras. A ocorrência do caranguejo-uçá é limitada à costa oeste do Oceano Atlântico, acompanhando a ocorrência dos manguezais. O objetivo deste trabalho foi caracterizar a estrutura do manguezal e a dinâmica populacional do caranguejo-uçá na foz do Rio São Francisco. Para a amostragem da vegetação, foram utilizados parâmetros fitossociológicos. A dinâmica populacional dos caranguejos foi avaliada por métodos não-destrutivos. O manguezal da foz do Rio São Francisco possui duas das mais comuns espécies do ecossistema
manguezal, R. mangle e L. racemosa, apresentando bons valores de parâmetros fitossociológicos. Os valores de densidade (ind./m2) e frequência das classes de tamanho indicam que esta área pertence ao estoque juvenil, portanto não é recomendada para a captura de caranguejos, pelo menos durante o período em que as coletas ocorreram. Finalmente, é necessário implementar programas de monitoramento do manguezal, bem como das populações, tanto no habitat natural, quanto nos locais de desembarque pesqueiro, a fim de realizar estimativas periódicas de densidade populacional deste importante recurso pesqueiro.
... A dinâmica da vegetacaõ de mangue pode modificar-se atraveś do tempo, com as mudancas na quantidade de inundações marinhas por mudanças no uso e ocupacaõ de uma determinada bacia e influxo de água doce proveniente dos rios, sendo excelentes bioindicadores, pois respondem aos gradientes de inundacaõ, de nutrientes e de salinidade (SCHAEFFER-NOVELLI; VALE; CINTROŃ, 2015). Tal heterogeneidade parece ser uma resposta à interacaõ de vaŕios fatores abioticos e antroṕicos que atuam em diferentes escalas locais e/ou regionais (microescala e mesoescala) e temporais (BERNINI; REZENDE, 2010;CUNHA-LIGNON et al., 2011). ...
... A vegetacaõ apresenta baixa diversidade, uma vez que poucas espećies conseguem se adaptar às oscilações da maré e salinidade, ao substrato inconsolidado e pouco oxigenado (CUNHA-LIGNON et al., 2011;LONDE et al., 2013;TOGNELLA, 2014). Nos manguezais brasileiros, ocorrem treŝ generos: Rhizophora L., Laguncularia C.F. e Gaertne Avicennia L., com um total de seis espećies: Rhizophoramangle L. Sergipe (SANTOS, 2013). ...
O Programa surgiu com o objetivo de bioprospectar, conhecer e divulgar a situação do Baixo São Francisco quanto aos aspectos sociais de comunidades ribeirinhas, comunidades de pescadores, situação da pesca, identificar os impactos e a qualidade da água do rio, a ictiofauna, problemas ocasionados pelo represamento, assoreamento, desmatamento, avaliar os poluentes presentes no ambiente aquático e o uso de agrotóxicos e os efeitos da cunha salina sobre as comunidades ribeirinhas e o ambiente, para propor ações mitigadoras por meio de programas de educação ambiental e ações prático-científicas.
O intuito do projeto é alavancar, na região, uma nova atividade participativa, por intermédio do conhecimento, através do monitoramento dos principais indicadores sociais e econômicos e dos impactos ambientais, assegurando a qualidade e a segurança alimentar. Tem também o enfoque de chamar a atenção para a situação do rio e seus problemas e divulgá-los para os principais órgãos de fomento e governantes, propondo ações para reduzir os impactos e a degradação da qualidade ambiental.
Avaliando a necessidade de gerar políticas públicas embasadas em dados científicos, as expedições científicas propõem a elaboração de grande diagnóstico e a definição de políticas públicas de modo participativo e multidisciplinar sobre a situação econômica, social e ambiental da região do Baixo São Francisco, observando os impactos da pesca, poluição aquática, desmatamento e assoreamento, patologias e parasitologia de peixes e crustáceos, índices de metais pesados e pesticidas e sua influência na qualidade do pescado e da água, determinando o perfil socioeconômico, qualificando a situação da saúde das populações ribeirinhas, adotando medidas de educação ambiental efetivas e caracterizando o manejo de diversas culturas intensivas sobre a qualidade da água para, com isso, efetivar um programa de biomonitoramento ambiental da calha principal do Rio São Francisco, utilizando tecnologias de ponta para a determinação de um padrão ambiental, com o intuito de propor ações mitigadores para os ecossistemas existentes na região em estudo.
As Expedições Científicas no Baixo São Francisco tiveram início em 2018, quando, durante cinco dias, cerca de 40 pesquisadores trabalharam em várias temáticas, como: educação ambiental, pesca, socioeconomia, ictiofauna, análise de água e de metais pesados, assoreamento, dentre outras, em cinco municípios do Baixo São Francisco (Traipu, Porto Real do Colégio, Igreja Nova, Penedo e Piaçabuçu), culminando na publicação de um diagnóstico referente a 2018, e, em junho de 2019, a publicação de um artigo científico sobre os dados dessa primeira edição. Em 2019, foi realizada a II Expedição Científica, com 50 pesquisadores e técnicos de 16 instituições que, durante 10 dias, trabalharam nos municípios de Piranhas, Pão de Açúcar, Traipu, Porto Real do Colégio-Propriá, Igreja Nova, Penedo-Neópolis, Piaçabuçu e na foz do São Francisco. Esta expedição teve por objetivo principal estudar todo o Baixo São Francisco, coletando informações e dados para, de posse dos resultados, propor ações para reduzir os problemas no rio.
Em 2020, mesmo diante da pandemia da Covid-19, o trabalho foi realizado com 53 pesquisadores, em 30 áreas. O projeto e as pesquisas desenvolvidas consolidaram de vez
as expedições e mostraram que é possível fazer ciência sem que nenhum pesquisador ou tripulante adoeça, tornando-se o Programa das Expedições Científicas do São Francisco,
como consequência, o maior evento prático científico do Brasil.
Em 2021, a exemplo dos anos anteriores, a Expedição Científica fez um trabalho em 35 linhas de pesquisa, com cerca de 66 pesquisadores, contemplando: Saúde bucal, oncologia, parasitoses e fisioterapia, qualidade de água e contaminantes; Pesca, ictiofauna, biodiversidade, tecnologia do pescado, reprodução de peixes; Tecnologias sociais e ambientais (certificação orgânica, manejo do solo, educação ambiental, doação de kits e jogos escolares às escolas rurais, doação de minitratores para associações, doação de notebooks e datashows para ações de educação ambiental, doação de PEV para coleta seletiva); Geoprocessamento, assoreamento, mata, Propriedade Intelectual, turismo de base comunitária, extração de produtos de plantas nativas da Caatinga, arqueologia subaquática e topologia do rio. Os municípios contemplados em 2021 foram: Piranhas-AL, Pão de Açúcar-AL, Traipu-AL, São Brás-AL, Propriá-SE, Igreja Nova-AL, Penedo-AL, Piaçabuçu-AL e Brejo Grande-SE. Além de seu caráter científico, a iniciativa ampliou as ações sociais com comunidades.
As pesquisas são realizadas in loco e nos diversos laboratórios, oriundas de esforços, fomento, apoio e ações de instituições como Universidade Federal de Alagoas (Ufal), Comitê de Bacia Hidrográfica do São Francisco (CBHSF), Fundação de Amparo à Pesquisa do Estado de Alagoas (Fapeal), Empresa Brasileira de Pesquisa Agropecuária (Embrapa) Tabuleiros Costeiros, Companhia de Desenvolvimento dos Vales do São Francisco e do Parnaíba (Codevasf )-5SR, Universidade Federal de Sergipe (UFS), Instituto de Inovação para o Desenvolvimento Rural Sustentável de Alagoas (Emater), Universidade Federal da Paraíba (UFPB), Universidade Federal de Rondônia (Unir), Secretaria de Meio Ambiente e Recursos Hídricos de Alagoas (Semarh-AL), Universidade Federal Rural de Pernambuco (UFRPE), Ministério de Ciência, Tecnologia e Inovações (MCTI), TV Gazeta de Alagoas, Pedreira Triunfo, Agência Peixe Vivo, Fundação Universitária de Desenvolvimento de Extensão e Pesquisa (Fundepes).
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... Here, we combined stoichiometric and isotopic approaches to investigate the effects of plant invasion on C and N stocks in sediment, C4 vs. C3 contributions to soil organic matter in a subtropical mangrove located in southeastern Brazil. Since 2010, mangroves at the north section of this region have been increasingly invaded by aquatic macrophytes (Cunha-Lignon et al., 2011Cunha-Lignon and Menghini, 2016;Prado et al., 2019;Sampaio et al., 2021). Several aquatic macrophytes are recognized as some of the most aggressive invasive species, given their exceedingly high productivity, ecological tolerance, and dispersal ability (Pieterse and Murfhy, 1993;Chambers et al., 2008). ...
... The northern portion (the Iguape region) is largely affected by the diversion of freshwater from the Ribeira de Iguape River through the artificial canal called Valo Grande (Mahiques et al., 2009(Mahiques et al., , 2013, that carries excess anthropic N from both sewage and agriculture to the estuary and mangroves in the Iguape region. Due to the high intake of fresh water and the consequent reduction in salinity, areas of fringe mangroves are invaded by aquatic macrophytes (Fig. 1 Supplementary) associated with reducing mangrove trees (Cunha-Lignon et al., 2011Cunha-Lignon and Menghini, 2016;Prado et al., 2019). ...
Plant invasion can primarily affect the structure and functioning of terrestrial and aquatic ecosystems. Although there is evidence that plant invasion can modify organic matter dynamics in mangroves, it is uncertain whether and to which extent these changes can affect carbon (C) and nitrogen (N) dynamics in the sediment-plant system. Here, we measured: (i) the structure of native vegetation and C and N sediment-plant system in subtropical mangroves subjected to aquatic macrophytes invasion in southeastern Brazil. We answered the following questions: i) Do invaded mangroves differ in aboveground biomass compared to non-invaded mangroves?; ii) Are there C4 macrophytes in these sites? iii) What are the C and N stocks in sediment of invaded mangroves? We quantified C and N concentrations and the isotopic signature of such elements (δ¹³C and δ¹⁵N) in the sediment-plant system, the C and N stocks in the sediment (0–20 cm depth), and mangrove aboveground biomass. Mangrove aboveground biomass was lower at invaded compared to non-invaded sites reflecting the species displacement in invaded sites. The sediment at invaded mangroves did not significantly contribute to C4 sources because of the large predominance of both mangrove and invasive C3 plants. While sediment C stocks were similar among study sites (∼47 Mg ha⁻¹), N stocks were lower at invaded (2.7 Mg ha⁻¹) comparing to non-invaded (3.2 Mg ha⁻¹) mangroves. The lower N stocks at invaded sites can reflect the higher leaf N concentrations and lower C:N ratios of invasive plants compared to mangroves. Thus, the effects of macrophytes invasion in subtropical mangroves are more apparent for vegetation structure and N stocks. C stocks alteration is expected the be detectable in the future.
... The Estuarine-Lagoon Complex (ELC) of Cananeia-Iguape, São Paulo State, Brazil is a Ramsar site (Ramsar 2017). Mangroves at the southern region of the complex are the widest and best conserved in São Paulo State (Cunha-Lignon et al. 2011). On the other hand, in the northern part of the complex, there was a significant increase in freshwater input due to the building of a canal in 1852 (locally known as "Valo Grande") to deviate flow from Ribeira de Iguape river (Mahiques et al. 2009(Mahiques et al. , 2013. ...
... This deviation, as well as the input of sewage and excess nutrients from agricultural activities in the Ribera de Iguape river basin resulted in important changes in the estuary (locally known as "Mar Pequeno") and associated mangroves. This possibly favored the colonization non-native species in the adjacent mangrove (Cunha-Lignon et al. 2011;Cunha-Lignon and Menghini 2016;Reis et al. 2019). ...
... The establishment and dominance of aquatic plants inside mangrove stands, however, is a consequence of disturbance and can result in negative effects on the native vegetation (Biswas et al. 2007(Biswas et al. , 2018. We observed large alterations on mangrove vegetation structure at the plots colonized by non-native plant species (+++NM) (Cunha-Lignon et al. 2011;Cunha-Lignon and Menghini 2016). The BADT data indicated the higher amount of dead mangrove trunks at the +++NM plots (53 % of basal area) compared to the other plots (up to 20 %). ...
The colonization and spread of non-native species are recognized as a critical driver of environmental change in mangrove ecosystems. However, environmental factors that favor non-native plant colonization in mangroves are still poorly understood. To fill this gap, we investigated the effect of selected abiotic factors controlling non-native plant species colonization in mangroves in Southeastern Brazil. We selected 18 plots in mangrove forests under different levels of anthropogenic N inputs, both colonized and non-colonized by non-native plants in the Estuarine-Lagoon Complex of Cananeia-Iguape, southeastern Brazil. We measured interstitial salinity, sediment nitrate and ammonium concentrations, and sediment physicochemical properties. We found that interstitial salinity at 10 cm depth followed by nitrate concentrations in sediment were the main factors associated with the occurrence of non-native species in the studied mangroves. Low salinity and increased N availability in sediment allowed for the success of non-native plants into mangrove forests, also resulting in high amount of dead mangrove trunks. Aiming to conserve and restore such areas, the restoration of abiotic conditions is the first step in the management of non-native species in this region.
... Important environmental changes have occurred in the last nearly 170 years, due to the opening of this channel, connecting the Ribeira de Iguape River to the lagoon system. Approximately 60% of the river's flow has been transferred to the lagoon system, leading to a drastic decrease in salinity (Mahiques et al. 2009 andCunha-Lignon et al. 2011;Prado et al. 2019). ...
Publications of the last three decades demonstrated the existence of some compact species groups within the Macrothrix Baird genus (Cladocera: Macrothricidae). Many species were included in hirsuticornis-group, laticornis-group, rosea-triserialis-group and paulensis-group, but not in Macrothrix marthae group. It has a peculiar set of morphological traits not observed in any other species, so far. Studying material from Ribeira de Iguape River, Brazil, we found some individuals that resemble M. marthae, which represent a new species described herein. Macrothrix lourdesae sp. nov shares with M. marthae similar morphology of Inner Distal Lobe setae and the same modifications on the fourth and fifth limbs. The main difference between them is related to the number of setae in the exopodite of the third limb. Observing the high number of morphological traits shared, it is possible to indicate that M. lourdesae sp. nov and M. marthae form a separate species group within the genus.
... Globally mangrove forests are known as among one of the most productive and biologically important ecosystems because they deliver a variety of vital and distinctive ecosystem goods and services to humankind and other coastal marine ecosystems like the mudflats, coral reefs, seagrass, etc [9]. Since time immemorial mangrove is been conventionally used for firewood, charcoal, alcohol, folk-lore therapeutics, roof thatching [10,11]. They act as nursery and breeding ground for the juveniles of many commercial fish, crustaceans, including avifauna and reptiles [12][13][14][15]. ...
Andaman and Nicobar Islands (ANI’s) being situated in the Tropical zone is the cradle of multi-disasters viz., cyclones, floods, droughts, land degradation, runoff, soil erosion, shallow landslides, epidemics, earthquakes, volcanism, tsunami and storm surges. Mangroves are one of the first visible reciprocators above land and sea surface to cyclonic storms, storm surges, and tsunamis among the coastal wetlands. The Indian Ocean 2004 tsunami was denoted as one of the most catastrophic ever recorded in humankind’s recent history. A mega-earthquake of Magnitude (9.3) near Indonesia ruptured the Andaman-Sunda plate triggered this tsunami. Physical fury, subsidence, upliftment, and prolonged water logging resulted in the massive loss of mangrove vegetation. A decade and half years after the 2004 tsunami, a study was initiated to assess the secondary ecological succession of mangrove in Tsunami Created Wetlands (TCWs) of south Andaman using Landsat satellite data products. Since natural ecological succession is a rather slow process and demands isotope techniques to establish a sequence of events succession. However, secondary ecological succession occurs in a short frame of time after any catastrophic event like a tsunami exemplifying nature’s resilience. Band-5 (before tsunami, 2003) and Band-6 (after tsunami, 2018) of Landsat 7 and Landsat-8 satellite respectively were harnessed to delineate mangrove patches and TCWs in the focus area using ArcMap 10.5, Geographic Information Systems (GIS) software. From the study, it was understood that Fimbrisstylis littoralis is the pioneering key-stone plant followed by Acrostichum aureum and Acanthus ilicifolius facilitating Avicennia spp/Rhizopara spp for ecological succession in the TCWs.
