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Tropical forests are some of the most biodiverse ecosystems in the world, yet their functioning is threatened by anthropogenic disturbances and climate change. Global actions to conserve tropical forests could be enhanced by having local knowledge on the forests' functional diversity and functional redundancy as proxies for their capacity to respond to global environmental change. Here we create estimates of plant functional diversity and redundancy across the tropics by combining a dataset of 16 morphological, chemical and photosynthetic plant traits sampled from 2,461 individual trees from 74 sites distributed across four continents together with local climate data for the past half century. Our findings suggest a strong link between climate and functional diversity and redundancy with the three trait groups responding similarly across the tropics and climate gradient. We show that drier tropical forests are overall less functionally diverse than wetter forests and that functional redundancy declines with increasing soil water and vapour pressure deficits. Areas with high functional diversity and high functional redundancy tend to better maintain ecosystem functioning, such as aboveground biomass, after extreme weather events. Our predictions suggest that the lower functional diversity and lower functional redundancy of drier tropical forests, in comparison with wetter forests, may leave them more at risk of shifting towards alternative states in face of further declines in water availability across tropical regions.
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Mudança Climática , Ecossistema , Florestas , Árvores , ÁguaRESUMO
Abstract Since its creation in 1960, the São Paulo State Research Foundation (FAPESP) has been supporting biodiversity research; however, in the early years, this large umbrella was still divided into botany, ecology, and zoology. This support became more effective by the establishment of the Research Program on Characterization, Conservation, and Sustainable Use of the Biodiversity of São Paulo State, better known as the BIOTA/FAPESP Program, in 1999. The program adopted the definition of biodiversity of the Convention on Biological Diversity and focused on 4 priorities: a) advancing scientific knowledge about Brazilian biodiversity; b) training high-level personnel (master's degrees, PhDs and postdocs) to carry out biodiversity research; c) transferring the advancement of knowledge to improve public policies on biodiversity conservation and restoration; and d) transferring private sector knowledge to economically explore the potential of Brazilian biodiversity by using it sustainably. This paper summarizes the major achievements of the BIOTA/FAPESP Program, now entering its third decade of existence.
Resumo: Desde sua criação em 1960, a Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) vem apoiando a pesquisa em biodiversidade, embora nos primeiros anos este grande guarda-chuva tenha sido dividido em botânica, ecologia e zoologia. Este apoio tornou-se mais efetivo com a criação em 1999 do Programa de Pesquisa em Caracterização, Conservação e Uso Sustentável da Biodiversidade do Estado de São Paulo, mais conhecido como Programa BIOTA/FAPESP. O Programa adotou a definição de biodiversidade da Convenção sobre Diversidade Biológica, e focalizou em 4 prioridades: a) o avanço do conhecimento científico sobre a biodiversidade brasileira, b) o treinamento pessoal de alto nível (mestrado, doutorado e pós-doutorado) para a realização de pesquisas em biodiversidade, c) a transferência do avanço do conhecimento para melhorar as políticas públicas de conservação e restauração da biodiversidade, d) a transferência para o setor privado do conhecimento para explorar economicamente o potencial da biodiversidade brasileira, utilizando-o de forma sustentável. Este documento resume as principais realizações do Programa BIOTA/FAPESP, atualmente denominado Programa de Pesquisa em Caracterização, Conservação, Restauração e Uso Sustentável da Biodiversidade, agora entrando em sua terceira década de existência.
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With humanity facing an unprecedented climate crisis, the conservation of tropical forests has never been so important - their vast terrestrial carbon stocks can be turned into emissions by climatic and human disturbances. However, the duration of these effects is poorly understood, and it is unclear whether impacts are amplified in forests with a history of previous human disturbance. Here, we focus on the Amazonian epicenter of the 2015-16 El Niño, a region that encompasses 1.2% of the Brazilian Amazon. We quantify, at high temporal resolution, the impacts of an extreme El Niño (EN) drought and extensive forest fires on plant mortality and carbon loss in undisturbed and human-modified forests. Mortality remained higher than pre-El Niño levels for 36 mo in EN-drought-affected forests and for 30 mo in EN-fire-affected forests. In EN-fire-affected forests, human disturbance significantly increased plant mortality. Our investigation of the ecological and physiological predictors of tree mortality showed that trees with lower wood density, bark thickness and leaf nitrogen content, as well as those that experienced greater fire intensity, were more vulnerable. Across the region, the 2015-16 El Niño led to the death of an estimated 2.5 ± 0.3 billion stems, resulting in emissions of 495 ± 94 Tg CO2 Three years after the El Niño, plant growth and recruitment had offset only 37% of emissions. Our results show that limiting forest disturbance will not only help maintain carbon stocks, but will also maximize the resistance of Amazonian forests if fires do occur.
Assuntos
Ciclo do Carbono , Secas , El Niño Oscilação Sul , Agricultura Florestal/estatística & dados numéricos , Fenômenos Fisiológicos Vegetais , Árvores/crescimento & desenvolvimento , Incêndios Florestais , Brasil , Florestas , HumanosRESUMO
Studies on the effects of human-driven forest disturbance usually focus on either biodiversity or carbon dynamics but much less is known about ecosystem processes that span different trophic levels. Herbivory is a fundamental ecological process for ecosystem functioning, but it remains poorly quantified in human-modified tropical rainforests.Here, we present the results of the largest study to date on the impacts of human disturbances on herbivory. We quantified the incidence (percentage of leaves affected) and severity (the percentage of leaf area lost) of canopy insect herbivory caused by chewers, miners, and gall makers in leaves from 1,076 trees distributed across 20 undisturbed and human-modified forest plots in the Amazon.We found that chewers dominated herbivory incidence, yet were not a good predictor of the other forms of herbivory at either the stem or plot level. Chewing severity was higher in both logged and logged-and-burned primary forests when compared to undisturbed forests. We found no difference in herbivory severity between undisturbed primary forests and secondary forests. Despite evidence at the stem level, neither plot-level incidence nor severity of the three forms of herbivory responded to disturbance. Synthesis. Our large-scale study of canopy herbivory confirms that chewers dominate the herbivory signal in tropical forests, but that their influence on leaf area lost cannot predict the incidence or severity of other forms. We found only limited evidence suggesting that human disturbance affects the severity of leaf herbivory, with higher values in logged and logged-and-burned forests than undisturbed and secondary forests. Additionally, we found no effect of human disturbance on the incidence of leaf herbivory.
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Habitat loss, fragmentation, and degradation have pervasive detrimental effects on tropical forest biodiversity, but the role of the surrounding land use (i.e., matrix) in determining the severity of these impacts remains poorly understood. We surveyed bird species across an interior-edge-matrix gradient to assess the effects of matrix type on biodiversity at 49 different sites with varying levels of landscape fragmentation in the Brazilian Atlantic Forest-a highly threatened biodiversity hotspot. Both area and edge effects were more pronounced in forest patches bordering pasture matrix, whereas patches bordering Eucalyptus plantation maintained compositionally similar bird communities between the edge and the interior and exhibited reduced effects of patch size. These results suggest the type of matrix in which forest fragments are situated can explain a substantial amount of the widely reported variability in biodiversity responses to forest loss and fragmentation.
Mediación de los Efectos de Área y de Borde sobre los Fragmentos de Bosque Causados por el Uso de Suelo Adyacente Resumen La pérdida del hábitat, la fragmentación y la degradación tienen efectos nocivos generalizados sobre la biodiversidad de los bosques tropicales. A pesar de esto, el papel del uso de suelo de los terrenos adyacentes (es decir, la matriz) en la determinación de la gravedad de estos impactos todavía está poco entendido. Censamos las especies de aves a lo largo de un gradiente de borde interno de matriz para evaluar los efectos del tipo de matriz sobre la biodiversidad en al menos 49 sitios con diferentes niveles de fragmentación del paisaje en el Bosque Atlántico Brasileño - un punto caliente de biodiversidad que se encuentra severamente amenazado. Tanto los efectos de área como los de borde estuvieron más pronunciados en los fragmentos de bosque que limitan con la matriz de pasturas, mientras que los fragmentos que limitan con plantaciones de Eucalyptus mantuvieron comunidades de aves similares en composición con aquellas entre el borde y el interior y mostraron efectos reducidos del tamaño de fragmento. Estos resultados sugieren que el tipo de matriz en el cual están situados los fragmentos de bosque puede explicar una cantidad sustancial de la ampliamente reportada variabilidad de respuestas a la pérdida del bosque y a la fragmentación.
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Conservação dos Recursos Naturais , Florestas , Animais , Biodiversidade , Brasil , EcossistemaRESUMO
Brazil hosts the largest expanse of tropical ecosystems within protected areas (PAs), which shelter biodiversity and support traditional human populations. We assessed the vulnerability to climate change of 993 terrestrial and coastal-marine Brazilian PAs by combining indicators of climatic-change hazard with indicators of PA resilience (size, native vegetation cover, and probability of climate-driven vegetation transition). This combination of indicators allows the identification of broad climate-change adaptation pathways. Seventeen PAs (20,611 km2 ) were highly vulnerable and located mainly in the Atlantic Forest (7 PAs), Cerrado (6), and the Amazon (4). Two hundred fifty-eight PAs (756,569 km2 ), located primarily in Amazonia, had a medium vulnerability. In the Amazon and western Cerrado, the projected severe climatic change and probability of climate-driven vegetation transition drove vulnerability up, despite the generally good conservation status of PAs. Over 80% of PAs of high or moderate vulnerability are managed by indigenous populations. Hence, besides the potential risks to biodiversity, the traditional knowledge and livelihoods of the people inhabiting these PAs may be threatened. In at least 870 PAs, primarily in the Atlantic Forest and Amazon, adaptation could happen with little or no intervention due to low climate-change hazard, high resilience status, or both. At least 20 PAs in the Atlantic Forest, Cerrado, and Amazonia should be targeted for stronger interventions (e.g., improvement of ecological connectivity), given their low resilience status. Despite being a first attempt to link vulnerability and adaptation in Brazilian PAs, we suggest that some of the PAs identified as highly or moderately vulnerable should be prioritized for testing potential adaptation strategies in the near future.
Evaluación de la Vulnerabilidad y Adaptación al Cambio Climático de Áreas Protegidas en Brasil Resumen Brasil alberga la mayor extensión de ecosistemas tropicales dentro de áreas protegidas (AP), que protegen la biodiversidad y sustentan a poblaciones humanas tradicionales. Evaluamos la vulnerabilidad al cambio climático de 993 AP brasileñas terrestres y costeras-marinas mediante la combinación de indicadores de riesgo de cambio climático con indicadores de la resiliencia de AP (tamaño, cobertura de vegetación nativa y la probabilidad de transición en la vegetación como consecuencia del cambio climático). Esta combinación de indicadores permite la identificación de amplias rutas de adaptación al cambio climático. Diecisiete AP (20,611 km2 ) fueron altamente vulnerables y se localizaron principalmente en el Bosque Atlántico (7 AP), El Cerrado (6) y la Amazonía (4). Doscientos cincuenta y ocho AP (756,569 km2 ), localizadas principalmente en la Amazonía, tuvieron vulnerabilidad media. En la Amazonía y el oeste de El Cerrado, el severo cambio climático proyectado y la probabilidad de transición de vegetación dirigida por el clima incrementó la vulnerabilidad, a pesar del estado de conservación generalmente bueno de las AP. Más de 80% de las AP con vulnerabilidad alta o media son manejadas por poblaciones indígenas. Por lo tanto, además de los riesgos potenciales para la biodiversidad, también hay amenazas para el conocimiento tradicional y las formas de vida de la gente que habita en esas AP. En por lo menos 870 AP, principalmente en el Bosque Atlántico y la Amazonía, la adaptación podría suceder con poca o ninguna intervención debido al bajo riesgo de cambio climático, estatus de resiliencia alta, o ambos. Por lo menos 20 AP en el Bosque Atlántico, El Cerrado y la Amazonía deberían ser objetivo de intervenciones mayores (e.g., mejoramiento de la conectividad ecológica), dada su estatus de resiliencia baja. A pesar de que es un primer intento para vincular vulnerabilidad y adaptación en AP brasileñas, sugerimos que algunas de las AP identificadas como alta o moderadamente vulnerables se deben priorizar para probar posibles estrategias de adaptación en un futuro próximo.
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Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Brasil , Mudança Climática , Florestas , HumanosRESUMO
Abstract: Biodiversity and ecosystems are important elements for addressing national and global socioeconomic and environmental crises, since they provide new development opportunities, for example, as source of job and income creation, and reduction in poverty and socioeconomic inequity. Brazilian biological diversity is also expressed in its immense cultural diversity, with a great variety of knowledge holders. These peoples possess vast knowledge on agrobiodiversity, fishing, fire management, natural medicine, among others of commercial, cultural and spiritual value. The main conclusions of this Summary for Police Makers is that land use changes and climate changes have been - and will continue to be throughout this century - the main drivers that result in the loss of biodiversity and ecosystem services in the country. Political interventions at different levels (from local to national, from public to private) and the enforcement of existing laws (regulatory mechanisms and incentives) are required to cope with the mitigation of the negative impacts of biodiversity and ecosystem services loss. Brazil has already a wide variety of policy instruments and socioenvironmental governance options, as well as global commitments (ODS, Aich Targets, Paris Agreement) related to the objective of a sustainable future. However, inefficient management control or lack of incentive to comply with the rules pose risks to consolidating the path to this future. The country has strong and capable institutions, but infrastructural problems, slow processes, inefficient measurements and judicial, social and ecological conflicts obstruct a proficient performance. There is a lack of communication between science and society which needs to be improved by establishing an effective flow that makes communication inclusive and representative, reaching public and private decision makers. Permanent efforts to integrate Science and policy knowledges are desirable to build confidence between policy makers and researchers.
Resumo: A biodiversidade e os ecossistemas são elementos importantes para enfrentar as crises socioeconômicas e ambientais nacionais e globais, uma vez que proporcionam novas oportunidades de desenvolvimento. Incorporar a biodiversidade na vida cotidiana é uma oportunidade de ouro para promover o uso sustentável da biodiversidade e dos serviços ecossistêmicos. A conservação e a restauração da biodiversidade, dos ecossistemas e de seus serviços associados mostram potencial para um novo desenvolvimento social e econômico, como fonte de geração de emprego e renda, redução da pobreza e da desigualdade socioeconômica. A diversidade biológica brasileira também se expressa em sua imensa diversidade cultural, com uma grande variedade de detentores de conhecimento indígenas e tradicionais. Esses povos possuem vasto conhecimento sobre agrobiodiversidade, pesca, manejo do fogo, medicina natural, entre outros de valor comercial, cultural e espiritual. As principais conclusões deste Sumário para Tomadores de Decisão é que as mudanças no uso da terra e as mudanças climáticas tenham sido - e continuarão sendo ao longo deste século - os principais vetores da perda de biodiversidade e serviços ecossistêmicos no país. Intervenções políticas em diferentes níveis (do local ao nacional, do público ao privado) e a aplicação das leis existentes (mecanismos regulatórios e incentivos) são necessárias para promover a mitigação dos impactos negativos sobre a biodiversidade e a perda de serviços ecossistêmicos. O Brasil já possui uma ampla variedade de instrumentos de política e opções de governança socioambiental, bem como compromissos globais (ODS, Metas de Aichi, Acordo de Paris) relacionados à possibilidade de um futuro sustentável. Entretanto, o controle ineficiente da gestão ou a falta de incentivo para cumprir as regras traz riscos para a consolidação do caminho para esse futuro. O país tem instituições fortes e capazes, mas problemas de infraestrutura, processos lentos, medidas ineficazes e conflitos judiciais, sociais e ecológicos impedem a realização de um desempenho eficiente. Há uma falta de comunicação entre a ciência e a sociedade que precisa ser melhorada por meio do estabelecimento de um fluxo efetivo que torne a comunicação inclusiva e representativa, alcançando os tomadores de decisão públicos e privados. Esforços permanentes para integrar essas duas esferas de conhecimento na sociedade são desejáveis para criar confiança entre os formuladores de políticas e os pesquisadores.
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BACKGROUND: Nitrogen (N) is an important macronutrient that controls the productivity of ecosystems and biological nitrogen fixation (BNF) is a major source of N in terrestrial systems, particularly tropical forests. Bamboo dominates theses forests, but our knowledge regarding the role of bamboo in ecosystem functioning remains in its infancy. We investigated the importance of a native bamboo species to the N cycle of a Neotropical forest. METHODS: We selected 100 sample units (100 m2 each) in a pristine montane Atlantic Forest, in Brazil. We counted all the clumps and live culms of Merostachys neesii bamboo and calculated the specific and total leaf area, as well as litter production and respective N content. Potential N input was estimated based on available data on BNF rates for the same bamboo species, whose N input was then contextualized using information on N cycling components in the study area. RESULTS: With 4,000 live culms ha-1, the native bamboo may contribute up to 11.7 kg N ha-1 during summer (January to March) and 19.6 kg N ha-1 in winter (July to September). When extrapolated for annual values, M. neesii could contribute more than 60 kg N ha-1y-1. DISCUSSION: The bamboo species' contribution to N input may be due to its abundance (habitat availability for microbial colonization) and the composition of the free-living N fixer community on its leaves (demonstrated in previous studies). Although some N is lost during decomposition, this input could mitigate the N deficit in the Atlantic Forest studied by at least 27%. Our findings suggest that M. neesii closely regulates N input and may better explain the high diversity and carbon stocks in the area. This is the first time that a study has investigated BNF using free-living N fixers on the phyllosphere of bamboo.
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Given anticipated climate changes, it is crucial to understand controls on leaf temperatures including variation between species in diverse ecosystems. In the first study of leaf energy balance in tropical montane forests, we observed current leaf temperature patterns on 3 tree species in the Atlantic forest, Brazil, over a 10-day period and assessed whether and why patterns may vary among species. We found large leaf-to-air temperature differences (maximum 18.3 °C) and high leaf temperatures (over 35 °C) despite much lower air temperatures (maximum 22 °C). Leaf-to-air temperature differences were influenced strongly by radiation, whereas leaf temperatures were also influenced by air temperature. Leaf energy balance modelling informed by our measurements showed that observed differences in leaf temperature between 2 species were due to variation in leaf width and stomatal conductance. The results suggest a trade-off between water use and leaf thermoregulation; Miconia cabussu has more conservative water use compared with Alchornea triplinervia due to lower transpiration under high vapour pressure deficit, with the consequence of higher leaf temperatures under thermal stress conditions. We highlight the importance of leaf functional traits for leaf thermoregulation and also note that the high radiation levels that occur in montane forests may exacerbate the threat from increasing air temperatures.
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Folhas de Planta/fisiologia , Árvores/fisiologia , Regulação da Temperatura Corporal/fisiologia , Brasil , Metabolismo Energético , Euphorbiaceae/metabolismo , Euphorbiaceae/fisiologia , Melastomataceae/metabolismo , Melastomataceae/fisiologia , Nyctaginaceae/metabolismo , Nyctaginaceae/fisiologia , Folhas de Planta/metabolismo , Temperatura , Árvores/metabolismo , Água/metabolismoRESUMO
Light is the key energy input for all vegetated systems. Forest light regimes are complex, with the vertical pattern of light within canopies influenced by forest structure. Human disturbances in tropical forests impact forest structure and hence may influence the light environment and thus competitiveness of different trees. In this study, we measured vertical diffuse light profiles along a gradient of anthropogenic disturbance, sampling intact, logged, secondary, and fragmented sites in the biodiversity hot spot of the Atlantic forest, southeast Brazil, using photosynthetically active radiation sensors and a novel approach with estimations of vertical light profiles from hemispherical photographs. Our results show clear differences in vertical light profiles with disturbance: Fragmented forests are characterized by rapid light extinction within their low canopies, while the profiles in logged forests show high heterogeneity and high light in the mid-canopy despite decades of recovery. The secondary forest showed similar light profiles to intact forest, but with a lower canopy height. We also show that in some cases the upper canopy layer and heavy liana infestations can severely limit light penetration. Light extinction with height above the ground and depth below the canopy top was highest in fragmented forest and negatively correlated with canopy height. The novel, inexpensive, and rapid methods described here can be applied to other sites to quantify rarely measured vertical light profiles.
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The Brazilian Atlantic Forest hosts one of the world's most diverse and threatened tropical forest biota. In many ways, its history of degradation describes the fate experienced by tropical forests around the world. After five centuries of human expansion, most Atlantic Forest landscapes are archipelagos of small forest fragments surrounded by open-habitat matrices. This 'natural laboratory' has contributed to a better understanding of the evolutionary history and ecology of tropical forests and to determining the extent to which this irreplaceable biota is susceptible to major human disturbances. We share some of the major findings with respect to the responses of tropical forests to human disturbances across multiple biological levels and spatial scales and discuss some of the conservation initiatives adopted in the past decade. First, we provide a short description of the Atlantic Forest biota and its historical degradation. Secondly, we offer conceptual models describing major shifts experienced by tree assemblages at local scales and discuss landscape ecological processes that can help to maintain this biota at larger scales. We also examine potential plant responses to climate change. Finally, we propose a research agenda to improve the conservation value of human-modified landscapes and safeguard the biological heritage of tropical forests.
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Conservação dos Recursos Naturais/métodos , Ecossistema , Florestas , Oceano Atlântico , Brasil , Mudança ClimáticaAssuntos
Biodiversidade , Conservação dos Recursos Naturais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Árvores/química , Alcaloides/análise , Brasil , Bases de Dados Factuais , Ecologia , Ensaios de Triagem em Larga Escala/métodos , Extratos Vegetais/química , Folhas de Planta/química , Rubiaceae/químicaRESUMO
We estimated carbon and nitrogen stocks in aboveground biomass (AGB) and belowground biomass (BGB) along an elevation range in forest sites located on the steep slopes of the Serra do Mar on the north coast of the State of São Paulo, southeast Brazil. In elevations of 100 m (lowland), 400 m (submontane), and 1000 m (montane) four 1-ha plots were established, and above- (live and dead) and belowground (live and dead) biomass were determined. Carbon and nitrogen concentrations in each compartment were determined and used to convert biomass into carbon and nitrogen stocks. The carbon aboveground stock (C(AGB)) varied along the elevation range from approximately 110 to 150 Mg·ha(-1), and nitrogen aboveground stock (N(AGB)), varied from approximately 1.0 to 1.9 Mg·ha(-1). The carbon belowground stock (C(BGB)) and the nitrogen belowground stock (N(BGB)) were significantly higher than the AGB and varied along the elevation range from approximately 200-300 Mg·ha(-1), and from 14 to 20 Mg·ha(-1), respectively. Finally, the total carbon stock (C(TOTAL)) varied from approximately 320 to 460 Mg·ha(-1), and the nitrogen total stock (N(TOTAL)) from approximately 15 to 22 Mg·ha(-1). Most of the carbon and nitrogen stocks were found belowground and not aboveground as normally found in lowland tropical forests. The above- and belowground stocks, and consequently, the total stocks of carbon and nitrogen increased significantly with elevation. As the soil and air temperature also decreased significantly with elevation, we found a significantly inverse relationship between carbon and nitrogen stocks and temperature. Using this inverse relationship, we made a first approach estimate that an increase of 1°C in soil temperature would decrease the carbon and nitrogen stocks in approximately 17 Mg·ha(-1) and 1 Mg·ha(-1) of carbon and nitrogen, respectively.
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Evolutionary biologists have long endeavored to document how many species exist on Earth, to understand the processes by which biodiversity waxes and wanes, to document and interpret spatial patterns of biodiversity, and to infer evolutionary relationships. Despite the great potential of this knowledge to improve biodiversity science, conservation, and policy, evolutionary biologists have generally devoted limited attention to these broader implications. Likewise, many workers in biodiversity science have underappreciated the fundamental relevance of evolutionary biology. The aim of this article is to summarize and illustrate some ways in which evolutionary biology is directly relevant. We do so in the context of four broad areas: (1) discovering and documenting biodiversity, (2) understanding the causes of diversification, (3) evaluating evolutionary responses to human disturbances, and (4) implications for ecological communities, ecosystems, and humans. We also introduce bioGENESIS, a new project within DIVERSITAS launched to explore the potential practical contributions of evolutionary biology. In addition to fostering the integration of evolutionary thinking into biodiversity science, bioGENESIS provides practical recommendations to policy makers for incorporating evolutionary perspectives into biodiversity agendas and conservation. We solicit your involvement in developing innovative ways of using evolutionary biology to better comprehend and stem the loss of biodiversity.