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1.
Commun Biol ; 5(1): 1028, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229543

RESUMO

The Pantanal wetland harbours the second largest population of jaguars in the world. Alongside climate and land-use changes, the recent mega-fires in the Pantanal may pose a threat to the jaguars' long-term survival. To put these growing threats into perspective, we addressed the reach and intensity of fires that have affected jaguar conservation in the Pantanal ecoregion over the last 16 years. The 2020 fires were the most severe in the annual series, burned 31% of the Pantanal and affected 45% of the estimated jaguar population (87% of these in Brazil); 79% of the home range areas, and 54% of the protected areas within home ranges. Fires consumed core habitats and injured several jaguars, the Pantanal's apex predator. Displacement, hunger, dehydration, territorial defence, and lower fecundity are among the impacts that may affect the abundance of the species. These impacts are likely to affect other less mobile species and, therefore, the ecological stability of the region. A solution to prevent the recurrence of mega-fires lies in combating the anthropogenic causes that intensify drought conditions, such as implementing actions to protect springs, increasing the number and area of protected areas, regulating fire use, and allocating fire brigades before dry seasons.


Assuntos
Panthera , Incêndios Florestais , Animais , Ecossistema , Estações do Ano , Áreas Alagadas
2.
PLoS One ; 16(12): e0261173, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34919593

RESUMO

It has been proposed that ecological theory develops in a pragmatic way. This implies that ecologists are free to decide what, from the knowledge available to them, they will use to build models and learn about phenomena. Because in fields that develop pragmatically knowledge generation is based on the decisions of individuals and not on a set of predefined axioms, the best way to produce theoretical synthesis in such fields is to assess what individuals are using to support scientific studies. Here, we present an approach for producing theoretical syntheses based on the propositions most frequently used to learn about a defined phenomenon. The approach consists of (i) defining a phenomenon of interest; (ii) defining a collective of scientists studying the phenomenon; (iii) surveying the scientific studies about the phenomenon published by this collective; (iv) identifying the most referred publications used in these studies; (v) identifying how the studies use the most referred publications to give support to their studies and learn about the phenomena; (vi) and from this, identifying general propositions on how the phenomenon is approached, viewed and described by the collective. We implemented the approach in a case study on the phenomenon of ecological succession, defining the collective as the scientists currently studying succession. We identified three propositions that synthesize the views of the defined collective about succession. The theoretical synthesis revealed that there is no clear division between "classical'' and "contemporary'' succession models, and that neutral models are being used to explain successional patterns alongside models based on niche assumptions. By implementing the pragmatic approach in a case study, we show that it can be successfully used to produce syntheses based on the actual activity of the scientific community studying the phenomenon. The connection between the resulting synthesis and research activity can be traced back through the methodological steps of the approach. This result can be used to understand how knowledge is being used in a field of study and can guide better informed decisions for future studies.


Assuntos
Ecossistema , Evolução Molecular , Modelos Teóricos , Humanos
3.
Sci Total Environ ; 752: 141967, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32892056

RESUMO

Hantavirus Cardiopulmonary Syndrome (HCPS) is a disease with high human lethality rates, whose transmission risk is directly related to the abundance of reservoir rodents. In the Brazilian Atlantic forest, the main reservoirs species, Oligoryzomys nigripes and Necromys lasiurus, are thought to increase in abundance with deforestation. Therefore, forest restoration may contribute to decrease HCPS transmission risk, a topic still unexplored, especially in tropical regions. Aiming at filling this research gap, we quantified the potential of forest restoration, as required by the current environmental legislation, to reduce the abundance of Hantavirus reservoir rodents in the Brazilian Atlantic Forest. Using a dataset on small mammal communities sampled at 104 sites, we modeled how the abundance of these two rodent species change with the percentage of forest cover and forest edge density. From the best model, we extrapolated rodent abundance to the entire Atlantic Forest, considering two scenarios: current and restored forest cover. Comparing the estimated abundance between these two scenarios, we show that forest restoration can reduce the abundance of O. nigripes up to 89.29% in 43.43% of Atlantic forest territory. For N. lasiurus, abundance decreased up to 46% in 44% of the Atlantic forest. To our knowledge, this is the first study linking forest restoration and zoonotic diseases. Our results indicate that forest restoration would decrease the chance of HCPS transmission in ~45% of the Atlantic forest, making the landscape healthier to ~2,8 million people living within this area. This positive effect of restoration on disease regulation should be considered as an additional argument to encourage and promote forest restoration in tropical areas around the world.


Assuntos
Orthohantavírus , Animais , Brasil , Florestas , Humanos , Roedores , Zoonoses
4.
Conserv Biol ; 35(1): 285-296, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32406127

RESUMO

Human-wildlife conflicts (HWC) are complex conservation challenges that impair both wildlife populations and human livelihood. Research on HWC, however, has traditionally approached ecological and human components separately, hampering a broader understanding of connections between ecological drivers and human dimensions of conflicts. We developed a model that integrates ecological and human components of HWC to investigate how the amount of remaining native forest (forest cover, a key ecological variable known to influence species occurrence and abundance) affects human experiences with wildlife (contact with species and attacks on livestock) and how such experiences influence tolerance via beliefs, emotions, and attitudes. We tested the model with piecewise structural equation modeling and data on human interactions with 3 mammals with different rarity and body size: opossum (Didelphis aurita), crab-eating fox (Cerdocyon thous), and puma (Puma concolor). Data were obtained by interviewing 114 landowners across 13 Atlantic Forest landscapes (10-50% forest cover). Forest cover was associated with high chance of attacks on livestock, and thus with low tolerance, only in the case of the puma. Effects of distinct experiences with wildlife on beliefs and emotions varied across species. Beliefs and emotions toward wildlife influenced tolerance toward all species, but negative emotions affected tolerance toward only with the puma. Conflicts with large carnivores, such as pumas, can then be understood as disservices provided by forests, indicating the relevance of framing HWC more broadly to consider trade-offs with ecosystems services. For some species, positive experiences with wildlife may counteract the negative effects of attacks on livestock in shaping tolerance. Models such as ours-that link ecological and human dimensions-can help identify more effective leverage points to improve HWC mitigation.


Vinculación de componentes humanos y ecológicos para entender los conflictos humano-fauna a nivel paisaje y especies Resumen Los conflictos humano-fauna (CHF) son retos complejos para la conservación pues perjudican tanto a las poblaciones de fauna como al sustento humano. Sin embargo, las investigaciones sobre los CHF por tradición han manejado a los componentes humanos y ecológicos de manera separada, dificultando un entendimiento más amplio de las conexiones entre los conductores ecológicos y las dimensiones humanas de estos conflictos. Desarrollamos un modelo que integra a los componentes ecológicos y humanos de los CHF para investigar cómo la cantidad de bosque nativo remanente (la cobertura de bosque, una variable ecológica importante que se sabe influye sobre la presencia y abundancia de las especies) afecta a las experiencias que las personas tienen con la fauna (contacto con especies y ataques al ganado) y cómo dichas experiencias influyen en la tolerancia por medio de creencias, emociones y actitudes. Probamos el modelo con un modelado de ecuación estructural por partes y datos sobre las interacciones humanas con tres mamíferos de diferente tamaño y rareza: la zarigüeya (Didelphis aurita), el zorro cangrejero (Cerdocyon thous) y el puma (Puma concolor). Los datos se obtuvieron por medio de entrevistas realizadas a 114 terratenientes distribuidos en 13 paisajes de bosque atlántico (10-50% de cobertura de bosque). La cobertura de bosque estuvo asociada con una alta probabilidad de ataques al ganado, y por lo tanto con una baja tolerancia, sólo para el caso del puma. Los efectos de las distintas experiencias con la fauna sobre las creencias y las emociones variaron con cada especie. Las creencias y las emociones hacia la fauna influyeron en la tolerancia hacia todas las especies, aunque las emociones negativas afectaron la tolerancia solamente hacia el puma. Los conflictos con los grandes carnívoros, como el puma, pueden entenderse como servicios negativos proporcionados por los bosques, lo que indica la relevancia de enmarcar a los CHF de manera más amplia para considerar las compensaciones con los servicios ambientales. Para algunas especies, las experiencias positivas con la fauna pueden contrarrestar los efectos negativos de los ataques al ganado en cuanto a la formación de la tolerancia. Los modelos como el nuestro - que conectan las dimensiones ecológicas y humanas - pueden ayudar a identificar puntos de ventaja más efectivos para mejorar la mitigación de los CHF.


Assuntos
Animais Selvagens , Carnívoros , Animais , Conservação dos Recursos Naturais , Ecossistema , Florestas , Humanos
5.
Conserv Biol ; 34(2): 449-461, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-30350891

RESUMO

The debate in the literature on the science-practice interface suggests a diversity of opinions on how to link science and practice to improve conservation. Understanding this diversity is key to addressing unequal power relations, avoiding the consideration of only dominant views, and identifying strategies to link science and practice. In turn, linking science and practice should promote conservation decisions that are socially robust and scientifically informed. To identify and describe the viewpoints of scientists and decision makers on how the science-practice interface should work in order to improve conservation decisions, we interviewed Brazilian scientists (ecologists and conservation scientists, n = 11) and decision makers (n = 11). We used Q methodology and asked participants to rank their agreement with 48 statements on how the science-practice interface should work in order to improve conservation decisions. We used principal component analysis to identify shared viewpoints. The predominant viewpoint, shared by scientists and decision makers, was characterized by valuing the integration of scientific and strategic knowledge to address environmental problems. The second viewpoint, held mostly by decision makers, was distinguished by assigning great importance to science in the decision-making process and calling for problem-relevant research. The third viewpoint, shared only by scientists, was characterized by an unwillingness to collaborate and a perception of scientists as producers of knowledge that may help decision makers. Most participants agreed organizations should promote collaboration and that actors and knowledge from both science and practice are relevant. Disagreements concerned specific roles assigned to actors, willingness to collaborate, and organizational and institutional arrangements considered effective to link science and practice. Our results suggest there is ample room for collaborations and that impediments lie mainly in existing organizations and formal institutional arrangements rather than in negative attitudes between scientists and decision makers.


Formas de Pensar Compartidas en Brasil sobre la Interrelación Ciencia-Práctica en la Ecología y la Conservación Resumen El debate en la literatura sobre la interrelación ciencia-práctica sugiere una diversidad de opiniones sobre cómo conectar a la ciencia con la práctica para mejorar la conservación. La comprensión de esta diversidad es clave para tratar con las relaciones desiguales de poder, evitar la considerar únicamente de los puntos de vista dominantes, e identificar las estrategias para vincular a la ciencia con la práctica. En cambio, la vinculación entre la ciencia y la práctica debería promover las decisiones de conservación que son socialmente fuertes y científicamente informadas. Entrevistamos a científicos (ecólogos y conservadores, n = 11) y tomadores de decisiones (n = 11) en Brasil para identificar y describir los puntos de vista de los científicos y de quienes toman las decisiones sobre cómo la interrelación ciencia-práctica debería trabajar con tal de mejorar las decisiones de conservación. Usamos la metodología Q y les pedimos a los participantes que clasificaran su acuerdo con 48 declaraciones sobre cómo la interrelación ciencia-práctica debería trabajar para mejorar las decisiones de conservación. Utilizamos un análisis de componentes principales para identificar los puntos de vista compartidos. El punto de vista predominante, compartido entre los científicos y quienes toman las decisiones, se caracterizó por el valor que le dio a la integración del conocimiento científico y el estratégico para tratar los problemas ambientales. El segundo punto de vista, compartido por la mayoría de quienes toman las decisiones, se distinguió por asignarle una gran importancia a la ciencia en cuanto al proceso de toma de decisiones y a la petición de investigación relevante para los problemas. El tercer punto de vista, compartido sólo entre los científicos, se caracterizó por el rechazo a colaborar y por la percepción de los científicos como productores de conocimiento que puede ayudar a quienes toman las decisiones. La mayoría de los participantes estuvo de acuerdo en que las organizaciones deberían promover la colaboración y en que los actores y el conocimiento científico y práctico son relevantes. Los desacuerdos estuvieron relacionados con los roles específicos asignados a los actores, el deseo de colaborar, y los arreglos institucionales y de organización considerados como efectivos para vincular a la ciencia con la práctica. Nuestros resultados sugieren que existe suficiente espacio para las colaboraciones y que los impedimentos se deben principalmente a las organizaciones existentes y a los arreglos institucionales formales en lugar de a las actitudes negativas entre los científicos y quienes toman las decisiones.


Assuntos
Conservação dos Recursos Naturais , Tomada de Decisões , Brasil , Ecologia , Organizações
6.
Glob Chang Biol ; 24(12): 5680-5694, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30216600

RESUMO

Secondary forests (SFs) regenerating on previously deforested land account for large, expanding areas of tropical forest cover. Given that tropical forests rank among Earth's most important reservoirs of carbon and biodiversity, SFs play an increasingly pivotal role in the carbon cycle and as potential habitat for forest biota. Nevertheless, their capacity to regain the biotic attributes of undisturbed primary forests (UPFs) remains poorly understood. Here, we provide a comprehensive assessment of SF recovery, using extensive tropical biodiversity, biomass, and environmental datasets. These data, collected in 59 naturally regenerating SFs and 30 co-located UPFs in the eastern Amazon, cover >1,600 large- and small-stemmed plant, bird, and dung beetles species and a suite of forest structure, landscape context, and topoedaphic predictors. After up to 40 years of regeneration, the SFs we surveyed showed a high degree of biodiversity resilience, recovering, on average among taxa, 88% and 85% mean UPF species richness and composition, respectively. Across the first 20 years of succession, the period for which we have accurate SF age data, biomass recovered at 1.2% per year, equivalent to a carbon uptake rate of 2.25 Mg/ha per year, while, on average, species richness and composition recovered at 2.6% and 2.3% per year, respectively. For all taxonomic groups, biomass was strongly associated with SF species distributions. However, other variables describing habitat complexity-canopy cover and understory stem density-were equally important occurrence predictors for most taxa. Species responses to biomass revealed a successional transition at approximately 75 Mg/ha, marking the influx of high-conservation-value forest species. Overall, our results show that naturally regenerating SFs can accumulate substantial amounts of carbon and support many forest species. However, given that the surveyed SFs failed to return to a typical UPF state, SFs are not substitutes for UPFs.


Assuntos
Biodiversidade , Biomassa , Florestas , Animais , Aves/fisiologia , Ciclo do Carbono , Besouros/fisiologia , Conservação dos Recursos Naturais , Conjuntos de Dados como Assunto , Ecossistema , Árvores , Clima Tropical
7.
Ecology ; 99(2): 498, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29399824

RESUMO

Measures of traits are the basis of functional biological diversity. Numerous works consider mean species-level measures of traits while ignoring individual variance within species. However, there is a large amount of variation within species and it is increasingly apparent that it is important to consider trait variation not only between species, but also within species. Mammals are an interesting group for investigating trait-based approaches because they play diverse and important ecological functions (e.g., pollination, seed dispersal, predation, grazing) that are correlated with functional traits. Here we compile a data set comprising morphological and life history information of 279 mammal species from 39,850 individuals of 388 populations ranging from -5.83 to -29.75 decimal degrees of latitude and -34.82 to -56.73 decimal degrees of longitude in the Atlantic forest of South America. We present trait information from 16,840 individuals of 181 species of non-volant mammals (Rodentia, Didelphimorphia, Carnivora, Primates, Cingulata, Artiodactyla, Pilosa, Lagomorpha, Perissodactyla) and from 23,010 individuals of 98 species of volant mammals (Chiroptera). The traits reported include body mass, age, sex, reproductive stage, as well as the geographic coordinates of sampling for all taxa. Moreover, we gathered information on forearm length for bats and body length and tail length for rodents and marsupials. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

8.
Biol Rev Camb Philos Soc ; 93(2): 1032-1055, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29160024

RESUMO

Applying scientific knowledge to confront societal challenges is a difficult task, an issue known as the science-practice gap. In Ecology and Conservation, scientific evidence has been seldom used directly to support decision-making, despite calls for an increasing role of ecological science in developing solutions for a sustainable future. To date, multiple causes of the science-practice gap and diverse approaches to link science and practice in Ecology and Conservation have been proposed. To foster a transparent debate and broaden our understanding of the difficulties of using scientific knowledge, we reviewed the perceived causes of the science-practice gap, aiming to: (i) identify the perspectives of ecologists and conservation scientists on this problem, (ii) evaluate the predominance of these perspectives over time and across journals, and (iii) assess them in light of disciplines studying the role of science in decision-making. We based our review on 1563 sentences describing causes of the science-practice gap extracted from 122 articles and on discussions with eight scientists on how to classify these sentences. The resulting process-based framework describes three distinct perspectives on the relevant processes, knowledge and actors in the science-practice interface. The most common perspective assumes only scientific knowledge should support practice, perceiving a one-way knowledge flow from science to practice and recognizing flaws in knowledge generation, communication, and/or use. The second assumes that both scientists and decision-makers should contribute to support practice, perceiving a two-way knowledge flow between science and practice through joint knowledge-production/integration processes, which, for several reasons, are perceived to occur infrequently. The last perspective was very rare, and assumes scientists should put their results into practice, but they rarely do. Some causes (e.g. cultural differences between scientists and decision-makers) are shared with other disciplines, while others seem specific to Ecology and Conservation (e.g. inadequate research scales). All identified causes require one of three general types of solutions, depending on whether the causal factor can (e.g. inadequate research questions) or cannot (e.g. scientific uncertainty) be changed, or if misconceptions (e.g. undervaluing abstract knowledge) should be solved. The unchanged predominance of the one-way perspective over time may be associated with the prestige of evidence-based conservation and suggests that debates in Ecology and Conservation lag behind trends in other disciplines towards bidirectional views ascribing larger roles to decision-makers. In turn, the two-way perspective seems primarily restricted to research traditions historically isolated from mainstream conservation biology. All perspectives represented superficial views of decision-making by not accounting for limits to human rationality, complexity of decision-making contexts, fuzzy science-practice boundaries, ambiguity brought about by science, and different types of knowledge use. However, joint knowledge-production processes from the two-way perspective can potentially allow for democratic decision-making processes, explicit discussions of values and multiple types of science use. To broaden our understanding of the interface and foster productive science-practice linkages, we argue for dialogue among different research traditions within Ecology and Conservation, joint knowledge-production processes between scientists and decision-makers and interdisciplinarity across Ecology, Conservation and Political Science in both research and education.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecologia , Lacunas da Prática Profissional , Política Pública , Tomada de Decisões , Humanos , Formulação de Políticas
9.
PLoS One ; 11(12): e0167691, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27942038

RESUMO

Understanding the multiple ways people value forests is important, as individual values regarding nature have been shown to partly determine willingness to participate in conservation initiatives. As individual values are influenced by past experiences, the way people value forests may be related to the ecosystem services they use and receive. We here aim to investigate if people value forests because of material and non-material benefits forest provide (material and non-material values), and if these values are defined by previous experiences associated with using forest resources and having frequent contact with forests. By interviewing 363 residents across 20 landscapes varying in forest cover in a post-frontier region in Amazonia, we evaluated: (1) if the use of forest resources-especially bushmeat, important for sustenance and cash income in virtually all tropical forests-is associated with attributing higher material value to forests; (2) whether the contact with forest (estimated by local forest cover and visits to forests) is associated with attributing higher non-material value to forests. As expected, respondents from households where hunting occurs and bushmeat consumption is more frequent attributed higher material value to forests, and those living in more deforested landscapes and that visited forests less often attributed lower non-material value to forests. The importance of bushmeat in shaping the way people value forests suggests that encouraging the sustainable use of this product will encourage forest conservation. Results also point to a potential dangerous reinforcing cycle: low forest cover and the loss of contact with forests may erode forest values and facilitate further deforestation. Engaging rural communities in forest conservation initiatives is challenging yet urgent in degraded landscapes, although harnessing appreciation for bushmeat could offer a starting point.


Assuntos
Conservação dos Recursos Naturais , Dieta Paleolítica , Agricultura Florestal/ética , Florestas , Adolescente , Adulto , Brasil , Feminino , Agricultura Florestal/economia , Agricultura Florestal/estatística & dados numéricos , Humanos , Indígenas Sul-Americanos/psicologia , Indígenas Sul-Americanos/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , População Rural
10.
PLoS One ; 11(10): e0163459, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27780250

RESUMO

Hantavirus Pulmonary Syndrome (HPS) is a disease caused by Hantavirus, which are negative-sense RNA viruses in the family Bunyaviridae that are highly virulent to humans. Numerous factors modify risk of Hantavirus transmission and consequent HPS risk. Human-driven landscape change can foster transmission risk by increasing numbers of habitat generalist rodent species that serve as the principal reservoir host. Climate can also affect rodent population dynamics and Hantavirus survival, and a number of social factors can influence probability of HPS transmission to humans. Evaluating contributions of these factors to HPS risk may enable predictions of future outbreaks, and is critical to development of effective public health strategies. Here we rely on a Bayesian model to quantify associations between annual HPS incidence across the state of São Paulo, Brazil (1993-2012) and climate variables (annual precipitation, annual mean temperature), landscape structure metrics (proportion of native habitat cover, number of forest fragments, proportion of area planted with sugarcane), and social factors (number of men older than 14 years and Human Development Index). We built separate models for the main two biomes of the state (cerrado and Atlantic forest). In both biomes Hantavirus risk increased with proportion of land cultivated for sugarcane and HDI, but proportion of forest cover, annual mean temperature, and population at risk also showed positive relationships in the Atlantic forest. Our analysis provides the first evidence that social, landscape, and climate factors are associated with HPS incidence in the Neotropics. Our risk map can be used to support the adoption of preventive measures and optimize the allocation of resources to avoid disease propagation, especially in municipalities that show medium to high HPS risk (> 5% of risk), and aimed at sugarcane workers, minimizing the risk of future HPS outbreaks.


Assuntos
Reservatórios de Doenças/virologia , Infecções por Hantavirus/epidemiologia , Roedores/virologia , Agricultura , Animais , Teorema de Bayes , Brasil/epidemiologia , Mudança Climática , Feminino , Infecções por Hantavirus/transmissão , Humanos , Incidência , Masculino , Dinâmica Populacional , Fatores Socioeconômicos
11.
Nature ; 535(7610): 144-7, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27362236

RESUMO

Concerted political attention has focused on reducing deforestation, and this remains the cornerstone of most biodiversity conservation strategies. However, maintaining forest cover may not reduce anthropogenic forest disturbances, which are rarely considered in conservation programmes. These disturbances occur both within forests, including selective logging and wildfires, and at the landscape level, through edge, area and isolation effects. Until now, the combined effect of anthropogenic disturbance on the conservation value of remnant primary forests has remained unknown, making it impossible to assess the relative importance of forest disturbance and forest loss. Here we address these knowledge gaps using a large data set of plants, birds and dung beetles (1,538, 460 and 156 species, respectively) sampled in 36 catchments in the Brazilian state of Pará. Catchments retaining more than 69­80% forest cover lost more conservation value from disturbance than from forest loss. For example, a 20% loss of primary forest, the maximum level of deforestation allowed on Amazonian properties under Brazil's Forest Code, resulted in a 39­54% loss of conservation value: 96­171% more than expected without considering disturbance effects. We extrapolated the disturbance-mediated loss of conservation value throughout Pará, which covers 25% of the Brazilian Amazon. Although disturbed forests retained considerable conservation value compared with deforested areas, the toll of disturbance outside Pará's strictly protected areas is equivalent to the loss of 92,000­139,000 km2 of primary forest. Even this lowest estimate is greater than the area deforested across the entire Brazilian Amazon between 2006 and 2015 (ref. 10). Species distribution models showed that both landscape and within-forest disturbances contributed to biodiversity loss, with the greatest negative effects on species of high conservation and functional value. These results demonstrate an urgent need for policy interventions that go beyond the maintenance of forest cover to safeguard the hyper-diversity of tropical forest ecosystems.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Florestas , Atividades Humanas , Clima Tropical , Animais , Aves/fisiologia , Brasil , Besouros/fisiologia , Incêndios/estatística & dados numéricos , Agricultura Florestal/estatística & dados numéricos , Plantas
13.
Proc Natl Acad Sci U S A ; 113(4): 1008-13, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26755597

RESUMO

The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods.


Assuntos
Biodiversidade , Florestas , Clima , Ecossistema , Evolução Molecular , Filogeografia
14.
Science ; 347(6223): 731, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25678655

RESUMO

Finney claims that we did not include transaction costs while assessing the economic costs of a set-aside program in Brazil and that accounting for them could potentially render large payments for environmental services (PES) projects unfeasible. We agree with the need for a better understanding of transaction costs but provide evidence that they do not alter the feasibility of the set-aside scheme we proposed.


Assuntos
Agricultura/economia , Biodiversidade , Conservação dos Recursos Naturais/economia , Árvores , Vertebrados/classificação , Animais , Humanos
16.
J Appl Ecol ; 51(4): 849-859, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25177046

RESUMO

1. In recent years, there has been a fast development of models that adjust for imperfect detection. These models have revolutionized the analysis of field data, and their use has repeatedly demonstrated the importance of sampling design and data quality. There are, however, several practical limitations associated with the use of detectability models which restrict their relevance to tropical conservation science. 2. We outline the main advantages of detectability models, before examining their limitations associated with their applicability to the analysis of tropical communities, rare species and large-scale data sets. Finally, we discuss whether detection probability needs to be controlled before and/or after data collection. 3. Models that adjust for imperfect detection allow ecologists to assess data quality by estimating uncertainty and to obtain adjusted ecological estimates of populations and communities. Importantly, these models have allowed informed decisions to be made about the conservation and management of target species. 4. Data requirements for obtaining unadjusted estimates are substantially lower than for detectability-adjusted estimates, which require relatively high detection/recapture probabilities and a number of repeated surveys at each location. These requirements can be difficult to meet in large-scale environmental studies where high levels of spatial replication are needed, or in the tropics where communities are composed of many naturally rare species. However, while imperfect detection can only be adjusted statistically, covariates of detection probability can also be controlled through study design. Using three study cases where we controlled for covariates of detection probability through sampling design, we show that the variation in unadjusted ecological estimates from nearly 100 species was qualitatively the same as that obtained from adjusted estimates. Finally, we discuss that the decision as to whether one should control for covariates of detection probability through study design or statistical analyses should be dependent on study objectives. 5.Synthesis and applications. Models that adjust for imperfect detection are an important part of an ecologist's toolkit, but they should not be uniformly adopted in all studies. Ecologists should never let the constraints of models dictate which questions should be pursued or how the data should be analysed, and detectability models are no exception. We argue for pluralism in scientific methods, particularly where cost-effective applied ecological science is needed to inform conservation policy at a range of different scales and in many different systems.

17.
Science ; 345(6200): 1041-5, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-25170150

RESUMO

Ecological set-asides are a promising strategy for conserving biodiversity in human-modified landscapes; however, landowner participation is often precluded by financial constraints. We assessed the ecological benefits and economic costs of paying landowners to set aside private land for restoration. Benefits were calculated from data on nearly 25,000 captures of Brazilian Atlantic Forest vertebrates, and economic costs were estimated for several restoration scenarios and values of payment for ecosystem services. We show that an annual investment equivalent to 6.5% of what Brazil spends on agricultural subsidies would revert species composition and ecological functions across farmlands to levels found inside protected areas, thereby benefiting local people. Hence, efforts to secure the future of this and other biodiversity hotspots may be cost-effective.


Assuntos
Agricultura/economia , Biodiversidade , Conservação dos Recursos Naturais/economia , Árvores , Vertebrados/classificação , Animais , Brasil , Análise Custo-Benefício , Humanos , Propriedade/economia , Filogenia
18.
PLoS One ; 8(12): e82369, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24324776

RESUMO

Habitat loss is the main driver of the current biodiversity crisis, a landscape-scale process that affects the survival of spatially-structured populations. Although it is well-established that species responses to habitat loss can be abrupt, the existence of a biodiversity threshold is still the cause of much controversy in the literature and would require that most species respond similarly to the loss of native vegetation. Here we test the existence of a biodiversity threshold, i.e. an abrupt decline in species richness, with habitat loss. We draw on a spatially-replicated dataset on Atlantic forest small mammals, consisting of 16 sampling sites divided between forests and matrix habitats in each of five 3600-ha landscapes (varying from 5% to 45% forest cover), and on an a priori classification of species into habitat requirement categories (forest specialists, habitat generalists and open-area specialists). Forest specialists declined abruptly below 30% of forest cover, and spillover to the matrix occurred only in more forested landscapes. Generalists responded positively to landscape heterogeneity, peaking at intermediary levels of forest cover. Open area specialists dominated the matrix and did not spillover to forests. As a result of these distinct responses, we observed a biodiversity threshold for the small mammal community below 30% forest cover, and a peak in species richness just above this threshold. Our results highlight that cross habitat spillover may be asymmetrical and contingent on landscape context, occurring mainly from forests to the matrix and only in more forested landscapes. Moreover, they indicate the potential for biodiversity thresholds in human-modified landscapes, and the importance of landscape heterogeneity to biodiversity. Since forest loss affected not only the conservation value of forest patches, but also the potential for biodiversity-mediated services in anthropogenic habitats, our work indicates the importance of proactive measures to avoid human-modified landscapes to cross this threshold.


Assuntos
Biodiversidade , Ecossistema , Árvores , Brasil , Conservação dos Recursos Naturais , Meio Ambiente , Geografia
19.
PLoS One ; 6(11): e27963, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22125643

RESUMO

BACKGROUND: The total amount of native vegetation is an important property of fragmented landscapes and is known to exert a strong influence on population and metapopulation dynamics. As the relationship between habitat loss and local patch and gap characteristics is strongly non-linear, theoretical models predict that immigration rates should decrease dramatically at low levels of remaining native vegetation cover, leading to patch-area effects and the existence of species extinction thresholds across fragmented landscapes with different proportions of remaining native vegetation. Although empirical patterns of species distribution and richness give support to these models, direct measurements of immigration rates across fragmented landscapes are still lacking. METHODOLOGY/PRINCIPAL FINDINGS: Using the Brazilian Atlantic forest marsupial Gray Slender Mouse Opossum (Marmosops incanus) as a model species and estimating demographic parameters of populations in patches situated in three landscapes differing in the total amount of remaining forest, we tested the hypotheses that patch-area effects on population density are apparent only at intermediate levels of forest cover, and that immigration rates into forest patches are defined primarily by landscape context surrounding patches. As expected, we observed a positive patch-area effect on M. incanus density only within the landscape with intermediate forest cover. Density was independent of patch size in the most forested landscape and the species was absent from the most deforested landscape. Specifically, the mean estimated numbers of immigrants into small patches were lower in the landscape with intermediate forest cover compared to the most forested landscape. CONCLUSIONS/SIGNIFICANCE: Our results reveal the crucial importance of the total amount of remaining native vegetation for species persistence in fragmented landscapes, and specifically as to the role of variable immigration rates in providing the underlying mechanism that drives both patch-area effects and species extinction thresholds.


Assuntos
Migração Animal , Ecossistema , Gambás/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Animais , Brasil , Conservação dos Recursos Naturais , Modelos Biológicos , Densidade Demográfica , Dinâmica Populacional
20.
Biota neotrop. (Online, Ed. port.) ; 10(4): 47-52, Oct.-Dec. 2010.
Artigo em Português | LILACS | ID: lil-578480

RESUMO

Os ecossistemas florestais do Brasil abrigam um dos mais altos níveis de diversidade de mamíferos da Terra, e boa parte dessa diversidade se encontra nas áreas legalmente protegidas em áreas de domínio privado. As reservas legais (RLs) e áreas de proteção permanente (APPs) representam estratégias importantes para a proteção e manutenção dessa diversidade. Mudanças propostas no Código Florestal certamente trarão efeitos irreversíveis para a diversidade de mamíferos no Brasil. Os mamíferos apresentam papéis-chave nos ecossistemas, atuando como polinizadores e dispersores de sementes. A extinção local de algumas espécies pode reduzir os serviços ecológicos nas RLs e APPs. Outra consequência grave da redução de áreas de vegetação nativa caso a mudança no Código Florestal seja aprovada será o aumento no risco de transmição de doenças, trazendo sério problemas a saúde pública no Brasil.


Forest ecosystems within Brazil host one of the highest levels of mammalian diversity on Earth, much of which within legally required forest set-asides in private landholdings. The Legal Reserves (RLs) and Permanent Protected Areas (APPs) of the Brazilian Forest Code provide an important strategy to maintain this diversity. Yet a proposed amendment to Brazil's 1965 forestry code would reduce protection of Brazil's forests, including the Amazon and the Atlantic forest, and bring irreversible detrimental effects to mammal diversity. Mammals are key components of forest ecosystem, providing important environmental services as pollinators, seed dispersers and ecosystem engineers. The local extinction of some species will negatively affect forest ecosystem service provisioning throughout the country. Another important effect of forest conversion within private properties, should the proposed changes happen, will be the emergence of new diseases, bringing serious public health problems in Brazil.

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