Biotropica最新文献

{"title":"Degradation and Fragmentation Effects on Structural Complexity in West-African Forest Patches","authors":"Samuel Hepner,&nbsp;Georges Alex Agonvonon,&nbsp;Martin Ehbrecht,&nbsp;Chima Iheaturu,&nbsp;Akomian Fortuné Azihou,&nbsp;Chinwe Ifejika Speranza","doi":"10.1111/btp.70012","DOIUrl":"https://doi.org/10.1111/btp.70012","url":null,"abstract":"<p>Tropical forests face alarming rates of deforestation and degradation, driven mainly by agricultural land expansion. West Africa is particularly affected by widespread forest fragmentation, leaving behind isolated forest patches in an agriculture-dominated landscape. Forest fragmentation and isolation can impact forest structural complexity, biomass, and species richness through various edge effects. The consequent loss of biodiversity and ecosystem services is expected to be more prominent in small and fragmented forests and closer to forest edges. We used terrestrial laser scanning to investigate patterns of forest structural complexity in 84 plots across seven forest patches in Togo, Benin, Nigeria, and Cameroon. We quantified forest structure using the stand structural complexity index (SSCI) and related it to tree species composition, distance to edge, and the modeled potential SSCI of primary forests as an ecological reference value to identify forest degradation. Spatial variability of SSCI within forest patches and plots indicates various areas of disturbance, ultimately accumulating to forest degradation. The overall trend suggests an increase in structural complexity, tree height, basal area, and tree species richness with increasing distance to the edge. However, these correlations were only significant for some of the forest patches analyzed. Comparison with the ecological reference value showed significant deviations for two forests, indicating degradation of forest structural integrity. Our results confirm and challenge theories of ecological dynamics in tropical forest patches in West Africa. Quantifying structural integrity helps to locate degradation and preserve the last remaining forest patches crucial for biodiversity, climate regulation, and forest products.</p>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/btp.70012","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Shifting Paradigms of Biodiversity Conservation in South Asia","authors":"Asmita Sengupta,&nbsp;G. Ravikanth,&nbsp;K. S. Seshadri,&nbsp;Milind Bunyan,&nbsp;T. Ganesh,&nbsp;Priyadarsanan Dharma Rajan,&nbsp;M. Soubadra Devy,&nbsp;N. A. Aravind","doi":"10.1111/btp.70013","DOIUrl":"https://doi.org/10.1111/btp.70013","url":null,"abstract":"<div>\u0000 \u0000 <p>South Asia, renowned for its rich biological heritage, is home to a quarter of the global human population and has been experiencing unprecedented biodiversity loss. Anthropogenic pressures are expected to rise in the coming decades, and how governance structures respond to them will be instrumental in preserving this biodiversity. In this paper, we provide an overview of the different conservation paradigms across South Asia and discuss how these can be strengthened. Nationwide networks of Protected Areas are the principal institutional tools wherein the State delineates landscapes for biodiversity conservation and denies or restricts people's rights to access space and resources. Since the 1970s, communities have partnered with the State and have also been involved in conservation initiatives by themselves. While State-led conservation has been invaluable in safeguarding biodiversity, it is exclusionary in terms of social justice and habitat heterogeneity. Conservation under State-community partnerships is inclusive in theory, but intrinsic power asymmetry is a limitation. Even completely community-driven biodiversity governance is stifled by inequity in access to resources. Moreover, these initiatives are usually too restricted in geographical scope to support viable populations of species and often have a lack of clarity regarding governance structures and monitoring. We suggest (a) implementing landscape-level conservation, (b) ensuring ecosystem representativeness, (c) providing further autonomy to local communities, (d) ensuring clarity on rules and regulations regarding decision-making authority and rights of access and benefit-sharing, and (e) multilateral collaborations across nations in the region to make conservation governance more effective in safeguarding both biodiversity and human well-being.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First Evidence of Fluorescence in Bornean Terrestrial and Freshwater Crabs","authors":"Leonardo Platania,&nbsp;Marta Ledesma Vega,&nbsp;Bob Zakaria,&nbsp;Andrea Vannini","doi":"10.1111/btp.70014","DOIUrl":"https://doi.org/10.1111/btp.70014","url":null,"abstract":"<div>\u0000 \u0000 <p>We report the first case of fluorescence in four species of terrestrial and freshwater crabs from Sarawak, Borneo. We observed blue fluorescence in all the individuals examined. This study provides detailed descriptions of the fluorescence characteristics across different species contributing to understanding this phenomenon in Decapoda.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143447080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecological Resilience in a Primate Community Affected by Gold Mining in Suriname","authors":"Marilyn Norconk,&nbsp;Cynthia L. Thompson,&nbsp;Arioené Vreedzaam,&nbsp;Sylvia Atsalis,&nbsp;Justin A. Ledogar,&nbsp;Chantal Landburg,&nbsp;Barth W. Wright","doi":"10.1111/btp.70007","DOIUrl":"https://doi.org/10.1111/btp.70007","url":null,"abstract":"<p>Tropical habitats in South America and Africa are being transformed by artisanal gold mining, but few studies have addressed how mining impacts animals at the community level. We assessed the long-term ecological resilience to mining disturbance for seven primate species (<i>Allouatta macconnelli</i>, \u0000 <i>Ateles paniscus</i>\u0000 , \u0000 <i>Cebus olivaceus</i>\u0000 , \u0000 <i>Chiropotes sagulatus</i>\u0000 , \u0000 <i>Pithecia pithecia</i>\u0000 , \u0000 <i>Saguinus midas</i>\u0000 , and \u0000 <i>Sapajus apella</i>\u0000 ) in the Brownsberg Nature Park, Suriname over a 20-year period. Using 11 trails and unpaved roads to calculate “encounter rates” (species encountered/km walked), we compared the encounter frequency, encounter location, and group size across four community-wide surveys in 2003, 2013, 2014, and 2023. We hypothesized that the primate response to gold mining would (1) affect species encounter rates, (2) shift the location of encounters relative to mining activity, and (3) impact group sizes. Intraspecific variation in encounter rates from 2003 to 2023 did not vary significantly, but minimum group sizes declined for all species (four species showing significant declines). The three more recent surveys also showed that two species were encountered in areas close to the top of the mountain. We suggest that in the context of intensified mining, the Brownsberg primate community maintained stable encounter rates for all species and some species shifted their ranges, as evidenced by higher encounter rates farther from the periphery of the study area. While this suggests a capacity for resilience in the face of mining-related disturbances, the decline in group sizes may be an early sign of an insidious community-wide effect.</p>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/btp.70007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143447082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patterns of Intrafruit Seed Abortion and Variation in Seed Mass of the Guanacaste Tree (Enterolobium cyclocarpum, Fabaceae) in Populations From Mexico and Costa Rica","authors":"Jorge A. Lobo,&nbsp;Edson J. Cristóbal-Pérez,&nbsp;María M. Chavarría,&nbsp;Mauricio Quesada","doi":"10.1111/btp.70008","DOIUrl":"https://doi.org/10.1111/btp.70008","url":null,"abstract":"<div>\u0000 \u0000 <p>Analyses of the variation in the abortion rate and mass of seeds of tropical trees are scarce, despite their importance in modulating seed production, plant recruitment, and herbivore foraging patterns. We studied these reproductive processes in a tropical dry forest tree species. We studied the patterns of intrafruit abortion and seed mass in fruits of the Guanacaste tree, <i>Enterolobium cyclocarpum</i>, in samples of trees from 5 populations in Mexico and Costa Rica. We analyzed the effects of developmental phase, fruit and maternal tree effects, and seed position within the fruit on the abortion rate and mass of seeds from mature and immature fruits. Naturally pollinated flowers were studied to determine the patterns of ovule fertilization within the ovaries. Overdispersion of the abortion rate per fruit within trees and a higher frequency of abortions in the extreme positions of the fruit were common patterns in all populations. These patterns were observed from the beginning of fruit formation. Ovules in the stylar position do not have higher survival rates, despite their precedence in fertilization. A negative relationship was found between abortion events and seed mass. Fruit-specific fertilization and developmental conditions seem to be the main factors driving the fruit abortion rate and seed mass, causing high variability in seed survival and mass within maternal trees. The correlation between the fruit abortion rate and seed mass may be related to the capacity of the fruit to drain maternal resources. These patterns are common to all studied Guanacaste tree populations.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143447081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perceived Predation Risk Affects Mammal Behavior at Amazonian Mineral Licks","authors":"Brian M. Griffiths,&nbsp;Jared Stabach,&nbsp;Joseph Kolowski","doi":"10.1111/btp.70009","DOIUrl":"https://doi.org/10.1111/btp.70009","url":null,"abstract":"<div>\u0000 \u0000 <p>Mineral licks are critical resources for herbivores in Amazonia and other tropical regions which may be deficient in dietary minerals or consuming alkaloid-laced leaves which may cause gastrointestinal issues. However, mineral licks are also important locations for predators, including human hunters. Animals visiting mineral licks must balance the benefits of relief of physiological stressors with the risk of predation, and they may employ behavioral adaptations to do so. We used camera trap data on six large-bodied mammal species at 52 mineral licks in the same watershed in the Peruvian Amazon to assess how mineral licks contribute to visiting species' perception of risk. We tested the effects of a range of covariates including direct and indirect measures of risk, habitat characteristics, and soil properties on visit duration, a behavioral adaptation species may use to mitigate risk, in a generalized linear mixed-effects modeling framework. Tapirs, collared peccaries, and paca minimized visit duration in risky licks, while howler monkeys, red brocket deer, and black agoutis had higher visit duration in risky licks, potentially due to increased vigilance and reduced feeding efficiency. The strong relationships between risk and behavior across species demonstrates the ecological value of mineral licks for both predators and prey, as prey must seek mineral licks but at great cost. Conserving mineral licks in landscapes may be a critical component to the conservation of both herbivores and carnivores in Amazonia, and for food security of local people.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143248893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitrogen and Phosphorus Allocation Strategies in a Chronosequence of Tropical Dry Forests: Plant Coordination and Environmental Drivers","authors":"Emma J. M. Bretherick,&nbsp;Juan M. Dupuy,&nbsp;Felipe García-Oliva,&nbsp;Anaitzi Rivero Villar,&nbsp;Julieta A. Rosell,&nbsp;Julio Campo","doi":"10.1111/btp.70004","DOIUrl":"https://doi.org/10.1111/btp.70004","url":null,"abstract":"<p>Identifying how limited resources, such as nutrients, are allocated across plant organs can provide new insights into ecophysiological strategies, as well as ecosystem nutrient cycles. Plants may allocate different nutrients within a specific organ or the same nutrient among different organs. In this study, we explored the allocation strategies of nitrogen (N) and phosphorus (P) in the leaves, stems, and roots of nine dominant tree species in secondary tropical dry forests using scaling analysis. The results showing that N and P have different scaling relationships within and among plant organs. The scaling relationships of P versus N concentrations in non-leaf organs were isometric across secondary succession and shifted in leaves from allometric (P concentration increased faster than N concentration) to isometric. The scaling relationships of N or P concentrations between metabolic (leaves vs. fine roots) or between structural (stems vs. coarse roots) plant organs tended to be isometric along succession. Whilst the scaling relationships of the same nutrient between metabolic versus structural plant organs tended to be allometric (N and P concentrations increased faster in woody organs than in metabolic organs) across succession. A principal component analysis suggests associations of nutrient allocation to woody organs with soil pH over the chronosequence and with vegetation structure and soil nutrient availability in the case of metabolic organs. These findings on the sensitivity in plant nutrient allocation to changes in soil and vegetation properties during secondary succession may have practical implications for carbon sequestration management and models and restoration of this threatened ecosystem.</p>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/btp.70004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143248892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Influence of Litter Diversity on Leaf Breakdown and the Colonization of Decomposer Communities in Subtropical Highland Grassland Streams","authors":"Renan de Souza Rezende,&nbsp;Marcelo da Silva Moretti,&nbsp;Emanuel Rampanelli Cararo,&nbsp;Walace Pandolpho Kiffer,&nbsp;Larissa Corteletti da Costa,&nbsp;Alan M. Tonin,&nbsp;José Francisco Gonçalves Junior","doi":"10.1111/btp.13424","DOIUrl":"https://doi.org/10.1111/btp.13424","url":null,"abstract":"<div>\u0000 \u0000 <p>Litter diversity can enhance leaf breakdown through selective effects when driven by a particular species or specific leaf chemical characteristics. We analyzed the influence of leaf mixtures on leaf breakdown and associated decomposers in a highland grassland stream that receives low-diversity leaf inputs. We incubated leaves of <i>Ocotea diospyrifolia</i>, <i>Nectandra megapotamica</i>, <i>Myrcia eugenioides</i>, and <i>Miconia flammea</i> in coarse mesh litter bags containing a leaf mixture of the four species, as well as leaves of each species in single treatments (6 streams × 3 replicates × 5 treatments = 90 sampling units). We found that leaves in single treatments had higher breakdown rates than the mixed treatment, suggesting that increased litter diversity did not positively influence leaf breakdown in highland grassland streams. Adaptations of decomposer assemblages to poorly structured riparian vegetation may have outweighed the potential effects of litter diversity. We found higher importance of leaf quality, measured by nutrient content, in driving leaf breakdown, with the effect of litter diversity on leaf breakdown rates depending on individual leaf chemical characteristics. Despite the lack of litter diversity positive effects on breakdown rates, the mixture treatment showed higher diversity of fungi and invertebrate decomposers. The leaf mixture may have increased habitat structure but reduced the number of individuals due to increased resource heterogeneity, favoring specialists. Functional feeding groups exhibited the expected patterns for their feeding strategies, with shredders benefiting from litter diversity and scrapers preferring single leaf treatments. Overall, riparian vegetation diversity was not crucial for organic matter processing but positively influenced decomposer diversity.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143248522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Standing Herbivory Is Not Affected by Tree Sex or Conspecific Density in a Dioecious Understory Tropical Tree Species","authors":"Leah Genth,&nbsp;Margaret R. Metz,&nbsp;Renato Valencia,&nbsp;Simon A. Queenborough","doi":"10.1111/btp.70006","DOIUrl":"https://doi.org/10.1111/btp.70006","url":null,"abstract":"<div>\u0000 \u0000 <p>Leaves are critical to plant photosynthesis and the loss of leaf area can have negative consequences for an individual's performance and fitness. Variation in plant defenses plays a large role in protecting their leaves from attack by insect herbivores. However, trade-offs in allocation among growth, reproduction, and defense may limit the availability of resources for any one aspect of a plant's life-history strategy, which would lead to greater herbivory in those plants that allocate more resources to growth or reproduction than to defense. Patterns of sex-biased herbivory in dioecious plants are well documented yet are known to vary in the direction (female or male) of their bias. A greater concentration of conspecifics may also increase herbivore attack through negative density dependence. In order to test the hypothesis that sex-biased herbivory varies as a function of conspecific density, we measured standing herbivory on 2350 leaves on 302 trees of the dioecious understory tree <i>Iryanthera hostmannii</i> (Myristicaceae) situated in a large forest dynamics plot in a lowland tropical rain forest in Ecuador. We found no difference in standing herbivory between the 169 male and 133 female trees, nor for focal trees surrounded by higher densities of conspecifics. The slow-growing, shade-tolerant growth patterns of <i>I. hostmannii</i> may contribute to suppressed differential expression of secondary sex characters in leaf defenses, leading to similar levels of herbivory between males and females. Considering the factors that most strongly affect herbivory in dioecious species is important in understanding the evolution of sex-related traits more broadly.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure of Epiphyte–Phorophyte Networks and Their Robustness to Species Loss in White-Sand Ecosystems in the Amazon","authors":"Viviane Pagnussat Klein,&nbsp;Talitha Mayumi Francisco,&nbsp;Adriano Costa Quaresma,&nbsp;Maria Teresa Fernandez Piedade","doi":"10.1111/btp.70005","DOIUrl":"https://doi.org/10.1111/btp.70005","url":null,"abstract":"<div>\u0000 \u0000 <p>The Amazon is the world's largest tropical forest, has a great diversity of species, and provides essential ecosystem services. However, anthropic exploratory processes have intensified and are seriously influencing this biome. Approaches that are based on ecological network theory are an excellent tool for describing the structure of communities, interactions between species, and the stability of ecosystems. Using a specific set of network metrics; the first epiphyte–phorophyte commensal network for the fragile white-sand ecosystems of the central Amazon was created. The structure and organization of interactions were analyzed and described; we also tested the stability of the system to simulate species loss. A total of 725 interactions between 52 phorophyte species and 118 vascular epiphytes were recorded in the white-sand ecosystem (WSE). The epiphyte–phorophyte network exhibited a nested structure, with a low degree of specialization (<i>H</i>₂′), connectance, modularity, and robustness. When the elimination of highly connected phorophytes was simulated, secondary extinctions in epiphytes were high, which indicates low stability of the system when disturbances occur. The generalist phorophyte <i>Aldina heterophylla</i> was particularly important, interacting with 89.0% of the species and hosting 75.0% of the epiphytes. Our results indicate that the richness and abundance of vascular epiphytes in WSEs is concentrated in a few phorophytes species, especially in large trees. As such, removing this species from the system can disrupt interactions, change the network's structure, and unbalance the entire ecosystem.</p>\u0000 </div>","PeriodicalId":8982,"journal":{"name":"Biotropica","volume":"57 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}