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Fig. S3. Population projection models for A. mexicanum constructed with data from six closed-canopy forest sites established at Los Tuxtlas. (A) Original matrix population model containing mean annual transition probabilities for 1975–1981. Life stages are as follows: seeds (S), infant palms or seedlings (I; 1-to 7-y-old palms with bifid leaves), juveniles (J; 8-to 17-y-old palms with pinnate leaves and stemless), immature individuals (IM; 1–50 cm in stem length), and mature stages (M1–M10; each one with a 50-cm stem length interval). (B) NPM containing mean annual transition probabilities for 2005–2013; transition probabilities for seeds and infant palms (indicated by an asterisk) were the same as recorded in 1975–1981. In both matrices, the first row contains fecundity rates (annual number of seeds produced per mature palm of a given stage), the main diagonal depicts stage-specific annual permanence probabilities, and the subdiagonal shows stage-specific annual progression probabilities. Adult palms are all individuals in the IM to M10 categories. Adult palms with a stem length longer than 50 cm are mature, reproductive individuals. To the right of each matrix, the vector (n) shows the number of individuals per life cycle stage in year 1975 or 2005.
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Anthropogenic disturbances affecting tropical forest reserves have been documented, but their ecological long-term cumulative effects are poorly understood. Habitat fragmentation and defaunation are two major anthropogenic threats to the integrity of tropical reserves. Based on a long-term (four decades) study, we document how these disturbances sy...
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... The impact of human disturbance on wildlife has been a longstanding concern in conservation biology (Carney and Sydeman, 1999;Coetzee and Chown, 2016;Cook et al., 2013). As human society rapidly develops, the demand for resources continuously expands, posing a serious threat to wildlife survival (Kadoya et al., 2022;Symes et al., 2018), and resulting in a massive loss of wildlife diversity (Magurran and Dornelas, 2010;Martínez-Ramos et al., 2016). In the current context of escalating biodiversity loss, understanding the distribution patterns and drivers of wildlife abundance is crucial for effective conservation and management activities (Ogutu et al., 2011;Wilson et al., 2017). ...
Wildlife conservation and management in human-dominated landscapes are major concerns for wildlife ecologists and managers. The dynamics of human disturbance, combined with seasonal limitations in the availability of nutritious foods, may restrict wildlife population growth and recovery. However, understanding how large mammal species adjust their population distribution in forest habitats with seasonal changes in food and disturbances requires a deeper and more extensive analysis. In this study, we found that three ungulate species, roe deer (Capreolus pygargus), sika deer (Cervus nippon), and wild boar (Sus scrofa), employ robust, conservative, and flexible distribution strategies, respectively, to adapt to the effects of seasonal changes and human disturbances. Moreover, croplands, villages, and grazing have some negative effects on the distribution of roe deer and sika deer, while wild boar can be highly abundant near human land use. Additionally, roe deer, sika deer, and wild boar are also affected by the abundance of shrub species they consume. During the cold season, the populations of the Amur tiger (Panthera tigris altaica) and Amur leopard (P. pardus orientalis) were primarily located near roads and dense forests, respectively. In the warm season, the distribution of both big cats was influenced by prey abundance, and Amur tigers also avoided grazing livestock. Nevertheless, the negative effects of human land use on Amur tigers and wild boars increased during the warm season, which was attributed to more frequent human activities during that time. Consequently, it is crucial to implement season-specific habitat management, particularly by regulating human disturbances during the warm season, in order to promote the recovery and expansion of populations of big cats and ungulates.
... In this paper, we focus on anthropogenic disturbance, which is frequently used to refer negatively to human impacts on forests with no critical discussion of the concept, with the human being seen as an a priori negative for nature (e.g. Martínez- Ramos et al., 2016;Moreno-Mateos et al., 2017). ...
How natural and cultural forces shaping tropical forested landscapes are conceptualised is of vital importance to Anthropocene debates. We examine two concepts: disturbance and landscape domestication. From the perspective of disturbance, humans-whether ancient or modern-are a priori negative for tropical forests, outside of and alien to nature. From this view, the Anthropocene is a planetary scale aggregation of disturbance. A more just vision of tropical forests, accepting anthropogenic influence on biodiversity, would combine 'disturbance' with other concepts that capture human agency and intentionality. Landscape domestication proposes that humans can shape ecology and plant and animal population demographics, making the landscape more productive and congenial for humans, upgrading or degrading the biodiversity of tropical forests. Herein, forest peoples shape the Anthropocene itself through their 'domestication' of the forest. Yet this approach can overdetermine culture, ignoring non-human agency, whilst human impacts can be seen as the outcome of intentional modifications to increase landscape productivity, at worst a disavowed projection of 'economic man'. Using the convivial scholarship framework of Nyamnjoh, we argue that these ideas give incomplete views of tropical forests in the Anthropocene and can be enriched by concepts derived from African worldviews with 'relationality' and 'wholeness' at their core. These are expressed in ohanife, deriving from Igbo
... Promoting and supporting the establishment of systematic long-term biodiversity monitoring programs that rely on empirical data, such as permanent plots, camera traps, and bird count points, is strongly recommended. Such programs would greatly enhance our understanding of biodiversity dynamics, identify cascading effects that threaten biodiversity (79), and improve the effectiveness of conservation efforts. A recent review by the International Panel for Biodiversity and Ecosystem Services highlights that engaging communities, particularly Indigenous people, in protected area management boosts reserves' effectiveness and fosters a mutually beneficial relationship between ecological and social aspects (80). ...
Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas’ effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demo- graphic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a “winner and loser” species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.
... This complexity may be one reason that despite the substantial body of evidence for effective Indigenous management of tropical forests, swidden remains widely thought to have negative impacts that lead to environmental degradation and deforestation 38 . So, on the one hand, ethnographic and ethnobiological research suggests that swidden societies possess significant cultural knowledge about the dynamics of tropical forest succession 39 and that patterns of swidden clearings reflect natural forest succession dynamics that optimize or enhance ecosystem services [40][41][42] ; while on the other hand, human activity has been shown to reduce functional redundancy and diversity across human land use gradients 43,44 . Nevertheless, a 2022 remote sensing analysis found less permanent forest loss in southern Belize where the most concentrated practices of swidden occur than in other parts of the country 45 . ...
Across the planet, Indigenous societies control, use, and manage large tracts of tropical forest that are crucial for combating climate change. Here we investigate whether customary Indigenous agricultural practices can increase forest species diversity using swidden (aka, slash-and-burn) agriculture. We examine the community lands surrounding two Q’eqchi’ Maya villages in southern Belize using high-resolution multispectral imagery that we collected with drones, ground truth data related to land use and history, and a plant and tree biodiversity survey. We use computational methods including simulation and Bayesian modeling to analyze the relationship between spectral diversity, forest diversity, and landscape disturbance. Our key result, replicated in both villages, is that the highest level of spectral diversity (a proxy for forest diversity) is associated with an intermediate level of forest disturbance. In conclusion, we suggest that concepts from complex adaptive systems can provide an important conceptual framework for understanding how ecosystem enhancement can emerge from customary Indigenous land use practices.
... Tropical forest ecosystems support two thirds of the Earth's terrestrial biological diversity including those conservation priority species (e. g., endangered, rare, and threatened species) (Laurance et al., 2012;Giam, 2017). However, tropical deforestation can directly lead to biodiversity loss when animal species no longer have their habitat (Martínez-Ramos et al., 2016;Alroy, 2017). Despite their critical roles, only a mere fraction (approximately 9.8%) of all existing tropical forests was designated as protected areas (Schmitt et al., 2008). ...
... In contrast, other consequences of defaunation are poorly documented. This includes the alteration in herbivory, seed predation, and dispersal interactions, and the cascading consequences on the community, as has been shown in the case of plant diversity changes in the understory of tropical forests (Dirzo and Miranda 1991;Camargo-Sanabria et al. 2015;Martínez-Ramos et al. 2016). This in turn may affect regeneration and major biogeochemical processes of the ecosystem. ...
Habitat loss due to land use change is recognized as one of the major drivers of contemporary defaunation. In this chapter, we examine tropical land mammal defaunation in Mexico from the perspective of changes in the natural land cover that represents the distribution range of a large sample (N = 252) of mammalian species. Based on a co-inertia analysis, we identified eight clusters of species based on the correlation between the configuration of the vegetation cover and the distribution ranges of mammals before and after the anthropogenic transformation of the major ecosystems of the country. We present detailed accounts of the identified clusters. Our analysis shows that species with distribution predominantly in tropical forests are considerably more challenged because tropical habitat transformation is very high (approaching 40% on average). In contrast, species that inhabit other ecosystems, mainly arid and semiarid vegetation, occur in areas where habitat transformation is lower (~20%) and their threats are consequently lower. Also, large-bodied species (with extensive habitat requirements) of restricted distribution seem to be the most impacted. However, other species that although of smaller body size, but are habitat specialists, are also at risk. We advocate for a deeper understanding of the differential resilience and susceptibility of mammals in the face of habitat transformation (and the synergies thereof with other anthropogenic impacts). Advances on this front may guide the implementation of effective conservation efforts to prevent a furthering of the country’s mammalian defaunation we document in this analysis.
... Overall, habitat loss is directly associated with the local extinction of large-and-medium-sized herbivorous mammals, unleashing a cascade of changes in ecosystems (Dirzo et al. 2014). The latter has a tremendous impact on forests because these species help maintain plant diversity via seed dispersal (Martínez-Ramos et al. 2016;Camargo-Sanabria et al. 2015). Moreover, herbivorous mammals also have significant anthropogenic pressure due to hunting for their meat, like the spotted paca Cuniculus paca. ...
Human activity has caused the decrease of about 20 % of the planet's vertebrate diversity and 25 % in their abundance. Many large and medium-sized herbivore mammals have gone extinct locally, unleashing a cascade of ecosystem changes. The spotted paca (Cuniculus paca) is impacted by hunting and anthropogenic habitat fragmentation and loss. To protect spotted pacas, it is essential to estimate anthropogenic effects on their geographic distribution. Through the use of primary biodiversity data, bioclimatic data, land-cover data, and a human footprint index, we modeled the distribution of C. paca. From 105 candidate models, only one model met our selection criteria. The variables with the highest contribution were the human footprint and annual precipitation. According to the model's performance curves, the spotted paca has low to medium tolerance of anthropogenic pressure. Cuniculus paca tolerates low to medium anthropogenic disturbance, which we hypothesize is related to reduced predator pressure in habitats modified by humans. Accounting for the costs and benefits of anthropogenic disturbance is essential to paca conservation.
... This finding proves that, besides tropical forests, anthropogenic disturbances also jeopardize the plant diversity in subtropical protected areas (Laurance et al., 2012). It also corresponds with the findings of intensified development in the periphery of the protected area, which has been a growing threat to plant diversity loss and ecosystem decay in reserves (Martinez-Ramos et al., 2016). The most apparent feature of human disturbance is the land use change. ...
This paper explores how human disturbance and hydrologic elements affect the spatial distribution pattern of plant diversity in the watershed, taking Shamu watershed in the World Natural Heritage Site as a case study. Spatial analysis of multisource remote sensing and plant diversity plots data were conducted using linear mixed effects models and structural equation models. Results revealed that the distribution of plant diversity in the watershed is mainly affected by human disturbance. However, under similar human disturbance levels, hydrologic elements also affect the plant diversity within the watershed. The topographic undulation and surface runoff significantly promote plant diversity, while the river network density, the watershed shape factor, the river longitudinal gradient do not. The influence of topographic undulation is more obvious than that of runoff on plant diversity, but the effect of topographic undulation and runoff on plant diversity is getting weaker from upstream to downstream within the watershed. In addition, the impact of hydrologic elements on plant diversity is mainly regulated by environmental factors Pre and Tem. The findings clarify how human disturbance and hydrologic elements affect plant diversity distribution within the watershed, optimizing the conservation theory of plant diversity resources and scientifically guiding the region's sustainable development.
... Empirical information, however, regarding the phylogenetic diversity, structure and composition of plant species assemblages in fragmented landscapes has been focused on adult trees, leaving aside other life stages such as seeds and seedlings (Santos et al., 2010;Arroyo-Rodríguez et al., 2012;Benitez-Malvido et al., 2014a). In the case of functional diversity, studies in tropical forests indicate functional homogenisation of tree species as a consequence of fragmentation (Silva and Tabarelli, 2000;Laurance et al., 2007;Á lvarez-Añorve et al., 2012;Santo-Silva et al., 2013;Martínez-Ramos et al., 2016;Emer et al., 2018). ...
... Arboreal primates play a critical role in enhancing the recruitment of several tree species by dispersing their seeds (Fuzessy et al., 2018). The disruptions of this mutualistic interaction through forest fragmentation and habitat loss predispose many tropical trees to local extinction, altering the composition and structure of the vegetation (Cordeiro and Howe, 2001;Cordeiro et al., 2009;González-Di Pierro et al., 2011Martínez-Ramos et al., 2016;Rother et al., 2016;Wandrag et al., 2017;Emer et al., 2018: Fuzessy et al., 2018. In fact, for many tree species seed dispersal services provided by primates cannot be compensated for by other frugivores (Medellin and Gaona, 1999;Clark et al., 2001;Emer et al., 2018;Fuzessy et al., 2018; but see Stevenson et al., 2021). ...
... In this study, tree species assemblage composition, structure and functioning in all life stages changed from fragments to continuous forest. Tree species extinction and vulnerability to extinction in fragments are taxonomically dependent (Vamosi and Wilson, 2008;Benítez-Malvido et al., 2014b;Martínez-Ramos et al., 2016). In our study, those large-seeded species dispersed by primates are at higher risk of being lost from fragments than small-seeded species that could be dispersed by other biotic and abiotic means. ...
Tropical rain forest fragmentation is considered one of the principal drivers of biodiversity loss worldwide. Fragmentation and defaunation of tropical rain forests affect the maintenance of their biodiversity in a myriad of ways. Old-growth forest plant and animal species are more likely to suffer from local extinction, not only because fragments frequently represent low quality habitats but also because of the loss of biotic interactions such as seed dispersal. In this study, we evaluated the maintenance of tree species diversity in the face of habitat fragmentation in southern Mexico using different approaches. Firstly, we used community phylogeny at different tree life stages (i.e., seeds, seedlings and adults). Secondly, we categorised plant species in different life stages into functional groups according to seed size (small seeds < 1 cm length and large seeds > 1 cm length) and, finally, by dispersal syndrome (predominantly primate dispersed). We searched for three sites of continuous forest as experimental controls where two important seed dispersers coexist, the howler (Alouatta pigra) and spider (Ateles geoffroyi) monkeys, and six forest fragments of similar sizes (ca. 3 to 6 ha). Three fragments were occupied only by howler monkeys, and three had no primates. We compared entire assemblages as well as assemblages of small-seeded and large-seeded species separately to determine the phylogenetic structure and patterns of species richness and the density of adult trees (> 10 cm dbh), seedlings (10 - 100 cm tall) and seed assemblages. Fragments and continuous forest differed in taxonomic species richness and density at all life stages when large-seeded species mainly dispersed by primates were solely considered, with numbers in unoccupied fragments being consistently lower than in continuous forests and occupied fragments. Phylogenetic clustering occurred in all habitats and for all life stages, predominantly for the seedling stage, indicating that the understory community is assembled via environmental filtering (including both biotic and abiotic processes). Habitats occupied by primates tended to present a higher phylogenetic clustering than unoccupied fragments, suggesting that primates select phylogenetically-related species in their diets and, importantly, that these foraging behaviours influence seedling recruitment patterns. The loss of taxonomic and functional biodiversity and the non-random extinction of tree species principally dispersed by primates, represents part of the evolutionary history that is being lost throughout fragmentation.
... This is highlighted in the research by a corresponding increase in the acreage covered by the grasslands and savannah forests as a result of the decline of montane forests due to urban development and plantation farming. In agreement to Martínez-Ramos et al. (2016) the research identifies how different land uses cause different disturbance dynamics and how protected areas experience more of natural disturbances as compared anthropogenic disturbances encouraging forest growth. ...
Forest disturbances play an important role in maintaining forest ecosystem functioning and heterogeneity. However, human action can change disturbance dynamics through changes in land use, forest management and conservation. Understanding the influence of human interventions on the disturbance dynamics is crucial for developing sustainable forest management schemes. To our knowledge, to date, there are only a limited spatio-temporal approaches used in assessing forest disturbance dynamics. This paper intends to address the question on how land use, forest conservation and management, affect the spatial and temporal patterns of forest disturbances in Zimbabwe's Eastern Highlands. Satellite imagery (Landsat) can aid in increasing the understanding of forest disturbance dynamics through analysis of sufficiently long time series forest data. Analysing of the time series forest data, covering a gradient of land uses, management and conservation regimes, will enable assessing the influence of human interventions to forest disturbance dynamics. The results of this research will help in developing a nationwide forest monitoring system and shed light on the complex dynamics of Zimbabwe forests.
