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1.
Nature ; 628(8008): 563-568, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38600379

RESUMO

More than a quarter of the world's tropical forests are exploited for timber1. Logging impacts biodiversity in these ecosystems, primarily through the creation of forest roads that facilitate hunting for wildlife over extensive areas. Forest management certification schemes such as the Forest Stewardship Council (FSC) are expected to mitigate impacts on biodiversity, but so far very little is known about the effectiveness of FSC certification because of research design challenges, predominantly limited sample sizes2,3. Here we provide this evidence by using 1.3 million camera-trap photos of 55 mammal species in 14 logging concessions in western equatorial Africa. We observed higher mammal encounter rates in FSC-certified than in non-FSC logging concessions. The effect was most pronounced for species weighing more than 10 kg and for species of high conservation priority such as the critically endangered forest elephant and western lowland gorilla. Across the whole mammal community, non-FSC concessions contained proportionally more rodents and other small species than did FSC-certified concessions. The first priority for species protection should be to maintain unlogged forests with effective law enforcement, but for logged forests our findings provide convincing data that FSC-certified forest management is less damaging to the mammal community than is non-FSC forest management. This study provides strong evidence that FSC-certified forest management or equivalently stringent requirements and controlling mechanisms should become the norm for timber extraction to avoid half-empty forests dominated by rodents and other small species.


Assuntos
Certificação , Agricultura Florestal , Florestas , Mamíferos , Animais , África Ocidental , Biodiversidade , Peso Corporal , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Elefantes , Agricultura Florestal/legislação & jurisprudência , Agricultura Florestal/métodos , Agricultura Florestal/normas , Gorilla gorilla , Mamíferos/anatomia & histologia , Mamíferos/classificação , Mamíferos/fisiologia , Fotografação , Roedores , Masculino , Feminino
2.
Nature ; 631(8021): 563-569, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39020035

RESUMO

The uptake of carbon dioxide (CO2) by terrestrial ecosystems is critical for moderating climate change1. To provide a ground-based long-term assessment of the contribution of forests to terrestrial CO2 uptake, we synthesized in situ forest data from boreal, temperate and tropical biomes spanning three decades. We found that the carbon sink in global forests was steady, at 3.6 ± 0.4 Pg C yr-1 in the 1990s and 2000s, and 3.5 ± 0.4 Pg C yr-1 in the 2010s. Despite this global stability, our analysis revealed some major biome-level changes. Carbon sinks have increased in temperate (+30 ± 5%) and tropical regrowth (+29 ± 8%) forests owing to increases in forest area, but they decreased in boreal (-36 ± 6%) and tropical intact (-31 ± 7%) forests, as a result of intensified disturbances and losses in intact forest area, respectively. Mass-balance studies indicate that the global land carbon sink has increased2, implying an increase in the non-forest-land carbon sink. The global forest sink is equivalent to almost half of fossil-fuel emissions (7.8 ± 0.4 Pg C yr-1 in 1990-2019). However, two-thirds of the benefit from the sink has been negated by tropical deforestation (2.2 ± 0.5 Pg C yr-1 in 1990-2019). Although the global forest sink has endured undiminished for three decades, despite regional variations, it could be weakened by ageing forests, continuing deforestation and further intensification of disturbance regimes1. To protect the carbon sink, land management policies are needed to limit deforestation, promote forest restoration and improve timber-harvesting practices1,3.


Assuntos
Dióxido de Carbono , Sequestro de Carbono , Florestas , Internacionalidade , Árvores , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análise , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Agricultura Florestal/legislação & jurisprudência , Agricultura Florestal/estatística & dados numéricos , Agricultura Florestal/tendências , Combustíveis Fósseis/efeitos adversos , Combustíveis Fósseis/provisão & distribuição , Taiga , Árvores/metabolismo , Árvores/crescimento & desenvolvimento , Clima Tropical
3.
Nature ; 620(7975): 807-812, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37612395

RESUMO

The United Nations recently agreed to major expansions of global protected areas (PAs) to slow biodiversity declines1. However, although reserves often reduce habitat loss, their efficacy at preserving animal diversity and their influence on biodiversity in surrounding unprotected areas remain unclear2-5. Unregulated hunting can empty PAs of large animals6, illegal tree felling can degrade habitat quality7, and parks can simply displace disturbances such as logging and hunting to unprotected areas of the landscape8 (a phenomenon called leakage). Alternatively, well-functioning PAs could enhance animal diversity within reserves as well as in nearby unprotected sites9 (an effect called spillover). Here we test whether PAs across mega-diverse Southeast Asia contribute to vertebrate conservation inside and outside their boundaries. Reserves increased all facets of bird diversity. Large reserves were also associated with substantially enhanced mammal diversity in the adjacent unprotected landscape. Rather than PAs generating leakage that deteriorated ecological conditions elsewhere, our results are consistent with PAs inducing spillover that benefits biodiversity in surrounding areas. These findings support the United Nations goal of achieving 30% PA coverage by 2030 by demonstrating that PAs are associated with higher vertebrate diversity both inside their boundaries and in the broader landscape.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Objetivos , Clima Tropical , Nações Unidas , Animais , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Mamíferos , Agricultura Florestal/legislação & jurisprudência , Agricultura Florestal/métodos , Agricultura Florestal/tendências
4.
Nature ; 597(7877): 516-521, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34471291

RESUMO

Biodiversity contributes to the ecological and climatic stability of the Amazon Basin1,2, but is increasingly threatened by deforestation and fire3,4. Here we quantify these impacts over the past two decades using remote-sensing estimates of fire and deforestation and comprehensive range estimates of 11,514 plant species and 3,079 vertebrate species in the Amazon. Deforestation has led to large amounts of habitat loss, and fires further exacerbate this already substantial impact on Amazonian biodiversity. Since 2001, 103,079-189,755 km2 of Amazon rainforest has been impacted by fires, potentially impacting the ranges of 77.3-85.2% of species that are listed as threatened in this region5. The impacts of fire on the ranges of species in Amazonia could be as high as 64%, and greater impacts are typically associated with species that have restricted ranges. We find close associations between forest policy, fire-impacted forest area and their potential impacts on biodiversity. In Brazil, forest policies that were initiated in the mid-2000s corresponded to reduced rates of burning. However, relaxed enforcement of these policies in 2019 has seemingly begun to reverse this trend: approximately 4,253-10,343 km2 of forest has been impacted by fire, leading to some of the most severe potential impacts on biodiversity since 2009. These results highlight the critical role of policy enforcement in the preservation of biodiversity in the Amazon.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/legislação & jurisprudência , Secas , Agricultura Florestal/legislação & jurisprudência , Floresta Úmida , Incêndios Florestais/estatística & dados numéricos , Animais , Brasil , Mudança Climática/estatística & dados numéricos , Florestas , Mapeamento Geográfico , Plantas , Árvores/fisiologia , Vertebrados
5.
Nature ; 583(7814): 72-77, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612223

RESUMO

Forests provide a series of ecosystem services that are crucial to our society. In the European Union (EU), forests account for approximately 38% of the total land surface1. These forests are important carbon sinks, and their conservation efforts are vital for the EU's vision of achieving climate neutrality by 20502. However, the increasing demand for forest services and products, driven by the bioeconomy, poses challenges for sustainable forest management. Here we use fine-scale satellite data to observe an increase in the harvested forest area (49 per cent) and an increase in biomass loss (69 per cent) over Europe for the period of 2016-2018 relative to 2011-2015, with large losses occurring on the Iberian Peninsula and in the Nordic and Baltic countries. Satellite imagery further reveals that the average patch size of harvested area increased by 34 per cent across Europe, with potential effects on biodiversity, soil erosion and water regulation. The increase in the rate of forest harvest is the result of the recent expansion of wood markets, as suggested by econometric indicators on forestry, wood-based bioenergy and international trade. If such a high rate of forest harvest continues, the post-2020 EU vision of forest-based climate mitigation may be hampered, and the additional carbon losses from forests would require extra emission reductions in other sectors in order to reach climate neutrality by 20503.


Assuntos
Agricultura Florestal/estatística & dados numéricos , Agricultura Florestal/tendências , Florestas , Biodiversidade , Biomassa , Sequestro de Carbono , Monitoramento Ambiental , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Europa (Continente) , União Europeia/economia , Agricultura Florestal/economia , Agricultura Florestal/legislação & jurisprudência , Aquecimento Global/prevenção & controle , História do Século XXI , Imagens de Satélites , Madeira/economia
9.
Proc Natl Acad Sci U S A ; 118(43)2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34663723

RESUMO

In Indonesia, 60 million people live within 1 km of state forest. The government of Indonesia plans to grant community titles for 12.7 million hectares of land to communities living in and around forests. These titles allow for using nontimber forest products, practicing agroforestry, operating tourism businesses, and selective logging in designated production zones. Here, we estimate the early effects of the program's rollout. We use data on the delineation and introduction date of community forest titles on 2.4 million hectares of land across the country. We find that, contrary to the objective of the program, community titles aimed at conservation did not decrease deforestation; if anything, they tended to increase forest loss. In contrast, community titles in zones aimed at timber production decreased deforestation, albeit from higher baseline forest loss rates.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Florestas , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Agricultura Florestal/legislação & jurisprudência , Humanos , Indonésia , Recursos Naturais
10.
Environ Manage ; 73(6): 1121-1133, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38710805

RESUMO

Though the federal government impacts private forest management across the United States through legislation such as the Clean Water Act, state-level regulations applied to private forest landowners vary remarkably. Despite this diversity of policies, little is known about how variations in regulatory intensity (defined here as number of forestry regulations) correlate with state-level political and socioeconomic characteristics. In this study, we use a quantitative approach to explore the intensity of regulation on forest practices impacting private landowners across all 50 states. We quantified intensity by tabulating the number of regulated forest practices, then used a quasi-Poisson regression to estimate the relationship between regulatory intensity and state-level characteristics, including forestland ownership types, the economic importance of the forest industry, and measures of state environmentalism. Results indicated a positive association between regulatory intensity and the percent of private corporate land, environmental voting records of elected officials, and direct democracy. Foresters and landowners may learn from these relationships, consider how to influence different policies, and build or achieve greater levels of public trust. This study starts to help us explain why state-level forestry policies differ, not just how they differ.


Assuntos
Conservação dos Recursos Naturais , Agricultura Florestal , Florestas , Propriedade , Estados Unidos , Agricultura Florestal/legislação & jurisprudência , Conservação dos Recursos Naturais/legislação & jurisprudência , Setor Privado , Regulamentação Governamental , Política Ambiental/legislação & jurisprudência
14.
Proc Natl Acad Sci U S A ; 115(52): 13164-13173, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30509982

RESUMO

Mineral and hydrocarbon extraction and infrastructure are increasingly significant drivers of forest loss, greenhouse gas emissions, and threats to the rights of forest communities in forested areas of Amazonia, Indonesia, and Mesoamerica. Projected investments in these sectors suggest that future threats to forests and rights are substantial, particularly because resource extraction and infrastructure reinforce each other and enable population movements and agricultural expansion further into the forest. In each region, governments have made framework policy commitments to national and cross-border infrastructure integration, increased energy production, and growth strategies based on further exploitation of natural resources. This reflects political settlements among national elites that endorse resource extraction as a pathway toward development. Regulations that protect forests, indigenous and rural peoples' lands, and conservation areas are being rolled back or are under threat. Small-scale gold mining has intensified in specific locations and also has become a driver of deforestation and degradation. Forest dwellers' perceptions of insecurity have increased, as have documented homicides of environmental activists. To explain the relationships among extraction, infrastructure, and forests, this paper combines a geospatial analysis of forest loss overlapped with areas of potential resource extraction, interviews with key informants, and feedback from stakeholder workshops. The increasing significance of resource extraction and associated infrastructure as drivers of forest loss and rights violations merits greater attention in the empirical analyses and conceptual frameworks of Sustainability Science.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Agricultura Florestal/legislação & jurisprudência , Florestas , Agricultura , Humanos
19.
Proc Natl Acad Sci U S A ; 113(52): 14958-14963, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-27956644

RESUMO

Policy makers around the world tout decentralization as an effective tool in the governance of natural resources. Despite the popularity of these reforms, there is limited scientific evidence on the environmental effects of decentralization, especially in tropical biomes. This study presents evidence on the institutional conditions under which decentralization is likely to be successful in sustaining forests. We draw on common-pool resource theory to argue that the environmental impact of decentralization hinges on the ability of reforms to engage local forest users in the governance of forests. Using matching techniques, we analyze longitudinal field observations on both social and biophysical characteristics in a large number of local government territories in Bolivia (a country with a decentralized forestry policy) and Peru (a country with a much more centralized forestry policy). We find that territories with a decentralized forest governance structure have more stable forest cover, but only when local forest user groups actively engage with the local government officials. We provide evidence in support of a possible causal process behind these results: When user groups engage with the decentralized units, it creates a more enabling environment for effective local governance of forests, including more local government-led forest governance activities, fora for the resolution of forest-related conflicts, intermunicipal cooperation in the forestry sector, and stronger technical capabilities of the local government staff.


Assuntos
Relações Comunidade-Instituição , Conservação dos Recursos Naturais , Agricultura Florestal/legislação & jurisprudência , Governo Local , Bolívia , Ecossistema , Florestas , Humanos , Peru , Política Pública , Árvores
20.
Proc Natl Acad Sci U S A ; 113(11): 2910-5, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26929349

RESUMO

Global markets for agricultural products, timber, and minerals are critically important drivers of deforestation. The supply chains driving land use change may also provide opportunities to halt deforestation. Market campaigns, moratoria, and certification schemes have been promoted as powerful tools to achieve conservation goals. Despite their promise, there have been few opportunities to rigorously quantify the ability of these nonstate, market-driven (NSMD) governance regimes to deliver conservation outcomes. This study analyzes the impacts of three NSMD governance systems that sought to end the conversion of natural forests to plantations in Chile at the start of the 21st century. Using a multilevel, panel dataset of land use changes in Chile, we identify the impact of participation within each of the governance regimes by implementing a series of matched difference-in-differences analyses. Taking advantage of the mosaic of different NSMD regimes adopted in Chile, we explore the relative effectiveness of different policies. NSMD governance regimes reduced deforestation on participating properties by 2-23%. The NSMD governance regimes we studied included collaborative and confrontational strategies between environmental and industry stakeholders. We find that the more collaborative governance systems studied achieved better environmental performance than more confrontational approaches. Whereas many government conservation programs have targeted regions with little likelihood of conversion, we demonstrate that NSMD governance has the potential to alter behavior on high-deforestation properties.


Assuntos
Conservação dos Recursos Naturais , Política Ambiental , Agricultura Florestal/organização & administração , Certificação/legislação & jurisprudência , Certificação/normas , Chile , Comércio , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/tendências , Política Ambiental/economia , Política Ambiental/legislação & jurisprudência , Agricultura Florestal/economia , Agricultura Florestal/legislação & jurisprudência , Agricultura Florestal/normas , Florestas
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