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1.
Proc Natl Acad Sci U S A ; 121(28): e2318029121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38950360

RESUMO

Indonesia has experienced rapid primary forest loss, second only to Brazil in modern history. We examined the fates of Indonesian deforested areas, immediately after clearing and over time, to quantify deforestation drivers in Indonesia. Using time-series satellite data, we tracked degradation and clearing events in intact and degraded natural forests from 1991 to 2020, as well as land use trajectories after forest loss. While an estimated 7.8 Mha (SE = 0.4) of forest cleared during this period had been planted with oil palms by 2020, another 8.8 Mha (SE = 0.4) remained unused. Of the 28.4 Mha (SE = 0.7) deforested, over half were either initially left idle or experienced crop failure before a land use could be detected, and 44% remained unused for 5 y or more. A majority (54%) of these areas were cleared mechanically (not by escaped fires), and in cases where idle lands were eventually converted to productive uses, oil palm plantations were by far the most common outcome. The apparent deliberate creation of idle deforested land in Indonesia and subsequent conversion of idle areas to oil palm plantations indicates that speculation and land banking for palm oil substantially contribute to forest loss, although failed plantations could also contribute to this dynamic. We also found that in Sumatra, few lowland forests remained, suggesting that a lack of remaining forest appropriate for palm oil production, together with an extensive area of banked deforested land, may partially explain slowing forest loss in Indonesia in recent years.


Assuntos
Conservação dos Recursos Naturais , Florestas , Indonésia , Árvores/crescimento & desenvolvimento , Agricultura
2.
Proc Natl Acad Sci U S A ; 121(6): e2305944121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38252845

RESUMO

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.


Assuntos
Biodiversidade , Ecossistema , Humanos , Animais , Agricultura , Animais Selvagens , Mudança Climática
3.
Proc Natl Acad Sci U S A ; 121(37): e2306496121, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39226355

RESUMO

High forest low deforestation jurisdictions (HFLDs) contain many of the world's last intact forests with historically low deforestation. Since carbon financing typically uses historical deforestation rates as baselines, HFLDs facing the prospect of future threats may receive insufficient incentives to be protected. We found that from 2002 to 2020, HFLDs (n = 310) experienced 44% higher deforestation rates than their historical baselines, and 60 HFLDs underwent periods of high deforestation (deforestation rate > 0.501%) at 0.983 ± 0.649% (mean ± SD)-a rate 7.5 times higher than the 10-y historical baseline of all HFLDs. For HFLDs to receive sufficient carbon finance requires baselines that can better reflect future deforestation trajectories of HFLDs. Using an empirical multifactorial model, we show that most contemporary HFLDs are expected to undergo higher deforestation from 2020 to 2038 than their historical baselines, with 72 HFLDs likely (>66% probability) to undergo high deforestation. Over the next 18 y, HFLDs are expected to lose 2.16 Mha y-1 of forests corresponding to 585 ± 74 MtCO2e y-1 (mean ± SE) of emissions. Efforts to protect HFLD forests from future threats will be crucial. In particular, improving baselining methods is key to ensuring that sufficient financing can flow to HFLDs to prevent deforestation.


Assuntos
Conservação dos Recursos Naturais , Florestas , Carbono , Árvores
4.
Proc Natl Acad Sci U S A ; 121(36): e2307521121, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39186646

RESUMO

Conservationists have long argued that inadequate funding for managing protected areas (PAs) jeopardizes their ability to achieve conservation goals. However, this claim has rarely been substantiated by quantitative evaluations. To address this, we examined the impact of funding on PA effectiveness both at the scale of 17 national PA systems across Latin America and within a PA system (Ecuador), for which we had precise historical financial data. Most PAs reduced deforestation between 2000 and 2010, demonstrating their crucial role in forest conservation. However, large deficits in funding considerably reduced the effectiveness of PAs in Ecuador (on average, a unit decrease in deficit leads to a 3.07% increase in effectiveness in avoiding deforestation). While differences in effectiveness between individual PAs in Ecuador were associated with funding deficits, national-level socioeconomic metrics (e.g., the Human Development Index) were the major factor when comparing PA system-level effectiveness among countries. This result suggests that while funding plays a major role in the performance of individual PAs, the quality of the socioeconomic context at the country level is critical for the overall performance of the PA systems. We, therefore, emphasize that maximizing the effectiveness of PAs requires a multilevel approach that includes better and more strategic resource allocation for individual PAs, combined with actions for strengthening the governance and institutions that regulate PA systems.


Assuntos
Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , América Latina , Humanos , Equador , Florestas , Fatores Socioeconômicos
5.
Proc Natl Acad Sci U S A ; 121(33): e2407357121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39110724

RESUMO

Satellite-based land use monitoring and farm-level traceability offer opportunities for targeted zero-deforestation interventions on private lands. Brazil's Rural Environmental Registry (Cadastro Ambiental Rural, or "CAR"), a land cadaster based on self-declaration of property boundaries, was created to monitor compliance with national forest laws. It has become an important enabling measure for sustainable supply chain initiatives like the Amazon Soy Moratorium. However, CAR enrollment is increasingly used to bolster illegal land claims, putting it at the heart of land grabbing dynamics. Self-declaration of properties in the CAR offers a unique situation to study land conflicts and their impact on land use decisions on a large scale. We quantified competing land claims among 846,420 registrations in the Brazilian Legal Amazon and applied a series of generalized linear mixed-effects models. We determined that CAR overlaps are more prevalent on larger registrations, in more densely settled areas, and in areas with less secure land tenure. We tested how landholders respond to land conflicts, finding significantly more deforestation and declared legal forest reserve on lands with multiple claims. CAR overlap results in an overestimation of forest reserves by up to 9.7 million hectares when considering double-counted and deforested areas of reserves, highlighting an overlooked form of Forest Code noncompliance. While the CAR continues to be used as evidence of land tenure, we conclude that the formalization of land claims through self-declarations is inadequate to decrease conflicts. CAR overlap information provides objective evidence of land conflict that authorities can leverage with field inspection to ensure peaceful occupation before issuing land titles.


Assuntos
Conservação dos Recursos Naturais , Brasil , Florestas , Humanos , Agricultura , Sistema de Registros , População Rural , Monitoramento Ambiental/métodos
6.
Proc Natl Acad Sci U S A ; 120(45): e2309123120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903256

RESUMO

Tropical deforestation impacts the climate through complex land-atmosphere interactions causing local and regional warming. However, whilst the impacts of deforestation on local temperature are well understood, the regional (nonlocal) response is poorly quantified. Here, we used remote-sensed observations of forest loss and dry season land-surface temperature during the period 2001 to 2020 to demonstrate that deforestation of the Amazon caused strong warming at distances up to 100 km away from the forest loss. We apply a machine learning approach to show nonlocal warming due to forest loss at 2-100 km length scales increases the warming due to deforestation by more than a factor 4, from 0.16 K to 0.71 K for each 10-percentage points of forest loss. We estimate that rapid future deforestation under a strong inequality scenario could cause dry season warming of 0.96 K across Mato Grosso state in southern Brazil over the period 2020 to 2050. Reducing deforestation could reduce future warming caused by forest loss to 0.4 K. Our results demonstrate the contribution of tropical deforestation to regional climate warming and the potential for reduced deforestation to deliver regional climate adaptation and resilience with important implications for sustainable management of the Amazon.


Assuntos
Conservação dos Recursos Naturais , Árvores , Florestas , Clima , Estações do Ano , Brasil
7.
Proc Natl Acad Sci U S A ; 120(51): e2309034120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38079550

RESUMO

There is an urgent need for reliable data on the impacts of deforestation on tropical biodiversity. The city-state of Singapore has one of the most detailed biodiversity records in the tropics, dating back to the turn of the 19th century. In 1819, Singapore was almost entirely covered in primary forest, but this has since been largely cleared. We compiled more than 200 y of records for 10 major taxonomic groups in Singapore (>50,000 individual records; >3,000 species), and we estimated extinction rates using recently developed and novel statistical models that account for "dark extinctions," i.e., extinctions of undiscovered species. The estimated overall extinction rate was 37% (95% CI [31 to 42%]). Extrapolating our Singapore observations to a future business-as-usual deforestation scenario for Southeast Asia suggests that 18% (95% CI [16 to 22%]) of species will be lost regionally by 2100. Our extinction estimates for Singapore and Southeast Asia are a factor of two lower than previous estimates that also attempted to account for dark extinctions. However, we caution that particular groups such as large mammals, forest-dependent birds, orchids, and butterflies are disproportionately vulnerable.


Assuntos
Borboletas , Animais , Singapura , Conservação dos Recursos Naturais , Extinção Biológica , Biodiversidade , Mamíferos
8.
Proc Natl Acad Sci U S A ; 119(27): e2202310119, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35759674

RESUMO

Human activities pose a major threat to tropical forest biodiversity and ecosystem services. Although the impacts of deforestation are well studied, multiple land-use and land-cover transitions (LULCTs) occur in tropical landscapes, and we do not know how LULCTs differ in their rates or impacts on key ecosystem components. Here, we quantified the impacts of 18 LULCTs on three ecosystem components (biodiversity, carbon, and soil), based on 18 variables collected from 310 sites in the Brazilian Amazon. Across all LULCTs, biodiversity was the most affected ecosystem component, followed by carbon stocks, but the magnitude of change differed widely among LULCTs and individual variables. Forest clearance for pasture was the most prevalent and high-impact transition, but we also identified other LULCTs with high impact but lower prevalence (e.g., forest to agriculture). Our study demonstrates the importance of considering multiple ecosystem components and LULCTs to understand the consequences of human activities in tropical landscapes.


Assuntos
Efeitos Antropogênicos , Biodiversidade , Conservação dos Recursos Naturais , Floresta Úmida , Agricultura , Brasil , Carbono , Humanos
9.
Proc Natl Acad Sci U S A ; 119(10): e2112063119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35238660

RESUMO

SignificanceTwo billion people across the planet suffer from nutrient deficiencies. Dietary diversification is key to solving this problem, yet many food and nutrition security policies, especially in low- and middle-income countries, still focus on increasing agricultural production and access to sufficient calories as the main solution. But calories are not all equal. Here, we show how deforestation in Tanzania caused a reduction in fruit and vegetable consumption (of 14 g per person per day) and thus vitamin A adequacy of diets. Using a combination of regression and weighting analyses to generate quasi-experimental quantitative estimates of the impacts of deforestation on people's food intake, our study establishes a causal link between deforestation and people's dietary quality.


Assuntos
Ingestão de Energia , Comportamento Alimentar , Frutas , População Rural , Verduras , Feminino , Humanos , Masculino , Tanzânia
10.
Proc Natl Acad Sci U S A ; 119(5)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35074869

RESUMO

International initiatives for reducing carbon emissions from deforestation and forest degradation (REDD+) could make critical, cost-effective contributions to tropical countries' nationally determined contributions (NDCs). Norway, a key donor of such initiatives, had a REDD+ partnership with Indonesia, offering results-based payments in exchange for emissions reductions calculated against a historical baseline. Central to this partnership was an area-based moratorium on new oil palm, timber, and logging concessions in primary and peatland forests. We evaluate the effectiveness of the moratorium between 2011 and 2018 by applying a matched triple difference strategy to a unique panel dataset. Treated dryland forest inside moratorium areas retained, at most, an average of 0.65% higher forest cover compared to untreated dryland forest outside the moratorium. By contrast, carbon-rich peatland forest was unaffected by the moratorium. Cumulative avoided dryland deforestation from 2011 until 2018 translates into 67.8 million to 86.9 million tons of emissions reductions, implying an effective carbon price below Norway's US$5 per ton price. Based on Norway's price, our estimated cumulative emissions reductions are equivalent to a payment of US$339 million to US$434.5 million. Annually, our estimates suggest a 3 to 4% contribution to Indonesia's NDC commitment of a 29% emissions reduction by 2030. Despite the Indonesia-Norway partnership ending in 2021, reducing emissions from deforestation remains critical for meeting this commitment. Future area-based REDD+ initiatives could build on the moratorium's outcomes by reforming its incentives and institutional arrangements, particularly in peatland forest areas.


Assuntos
Carbono/economia , Conservação dos Recursos Naturais/economia , Análise Custo-Benefício/economia , Mudança Climática/economia , Florestas , Indonésia , Noruega , Óleo de Palmeira/economia , Paris
11.
Proc Natl Acad Sci U S A ; 119(2)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34983872

RESUMO

Deforestation affects local and regional hydroclimate through changes in heating and moistening of the atmosphere. In the tropics, deforestation leads to warming, but its impact on rainfall is more complex, as it depends on spatial scale and synoptic forcing. Most studies have focused on Amazonia, highlighting that forest edges locally enhance convective rainfall, whereas rainfall decreases over drier, more extensive, deforested regions. Here, we examine Southern West Africa (SWA), an example of "late-stage" deforestation, ongoing since 1900 within a 300-km coastal belt. From three decades of satellite data, we demonstrate that the upward trend in convective activity is strongly modulated by deforestation patterns. The frequency of afternoon storms is enhanced over and downstream of deforested patches on length scales from 16 to 196 km, with greater increases for larger patches. The results are consistent with the triggering of storms by mesoscale circulations due to landscape heterogeneity. Near the coast, where sea breeze convection dominates the diurnal cycle, storm frequency has doubled in deforested areas, attributable to enhanced land-sea thermal contrast. These areas include fast-growing cities such as Freetown and Monrovia, where enhanced storm frequency coincides with high vulnerability to flash flooding. The proximity of the ocean likely explains why ongoing deforestation across SWA continues to increase storminess, as it favors the impact of mesoscale dynamics over moisture availability. The coastal location of deforestation in SWA is typical of many tropical deforestation hotspots, and the processes highlighted here are likely to be of wider global relevance.


Assuntos
Processos Climáticos , Conservação dos Recursos Naturais/tendências , África Ocidental , Agricultura , Brasil , Inundações , Florestas , Namíbia , Chuva , Árvores
12.
Proc Natl Acad Sci U S A ; 119(38): e2118273119, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36095187

RESUMO

Growing demand for minerals continues to drive deforestation worldwide. Tropical forests are particularly vulnerable to the environmental impacts of mining and mineral processing. Many local- to regional-scale studies document extensive, long-lasting impacts of mining on biodiversity and ecosystem services. However, the full scope of deforestation induced by industrial mining across the tropics is yet unknown. Here, we present a biome-wide assessment to show where industrial mine expansion has caused the most deforestation from 2000 to 2019. We find that 3,264 km2 of forest was directly lost due to industrial mining, with 80% occurring in only four countries: Indonesia, Brazil, Ghana, and Suriname. Additionally, controlling for other nonmining determinants of deforestation, we find that mining caused indirect forest loss in two-thirds of the investigated countries. Our results illustrate significant yet unevenly distributed and often unmanaged impacts on these biodiverse ecosystems. Impact assessments and mitigation plans of industrial mining activities must address direct and indirect impacts to support conservation of the world's tropical forests.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Florestas , Mineração , Conservação dos Recursos Naturais/métodos
13.
Glob Chang Biol ; 30(1): e17077, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273583

RESUMO

Deforestation of tropical rainforests is a major land use change that alters terrestrial biogeochemical cycling at local to global scales. Deforestation and subsequent reforestation are likely to impact soil phosphorus (P) cycling, which in P-limited ecosystems such as the Amazon basin has implications for long-term productivity. We used a 100-year replicated observational chronosequence of primary forest conversion to pasture, as well as a 13-year-old secondary forest, to test land use change and duration effects on soil P dynamics in the Amazon basin. By combining sequential extraction and P K-edge X-ray absorption near edge structure (XANES) spectroscopy with soil phosphatase activity assays, we assessed pools and process rates of P cycling in surface soils (0-10 cm depth). Deforestation caused increases in total P (135-398 mg kg-1 ), total organic P (Po ) (19-168 mg kg-1 ), and total inorganic P (Pi ) (30-113 mg kg-1 ) fractions in surface soils with pasture age, with concomitant increases in Pi fractions corroborated by sequential fractionation and XANES spectroscopy. Soil non-labile Po (10-148 mg kg-1 ) increased disproportionately compared to labile Po (from 4-5 to 7-13 mg kg-1 ). Soil phosphomonoesterase and phosphodiesterase binding affinity (Km ) decreased while the specificity constant (Ka ) increased by 83%-159% in 39-100y pastures. Soil P pools and process rates reverted to magnitudes similar to primary forests within 13 years of pasture abandonment. However, the relatively short but representative pre-abandonment pasture duration of our secondary forest may not have entailed significant deforestation effects on soil P cycling, highlighting the need to consider both pasture duration and reforestation age in evaluations of Amazon land use legacies. Although the space-for-time substitution design can entail variation in the initial soil P pools due to atmospheric P deposition, soil properties, and/or primary forest growth, the trend of P pools and process rates with pasture age still provides valuable insights.


Assuntos
Floresta Úmida , Solo , Solo/química , Fósforo , Ecossistema , Conservação dos Recursos Naturais , Florestas
14.
Glob Chang Biol ; 30(3): e17211, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38439736

RESUMO

Most protected area (PA) planning aims to improve biota representation within the PA system, but this does not necessarily achieve the best outcomes for biota retention across regions when we also consider habitat loss in areas outside the PA system. Here, we assess the implications that different PA expansion strategies can have on the retention of species habitat across an entire region. Using retention of forest habitat for Colombia's 550 forest-dependent bird species as our outcome variable, we found that when a minimum of 30% of each species' habitat was included in the PA system, a pattern of PA expansion targeting areas at highest deforestation risk (risk-prevention) led to the retention, on average, of 7.2% more forest habitat per species by 2050 than did a pattern that targeted areas at lowest risk (risk-avoidance). The risk-prevention approach cost more per km2 of land conserved, but it was more cost-effective in retaining habitat in the landscape (50%-69% lower cost per km2 of avoided deforestation). To have the same effectiveness preventing habitat loss in Colombia, the risk-avoidance approach would require more than twice as much protected area, costing three times more in the process. Protected area expansion should focus on the contributions of PAs to outcomes not only within PA systems themselves, but across entire regions.


La mayor parte de la planificación de áreas protegidas (AP) tiene como objetivo mejorar la representación de la biota dentro del sistema de AP, pero esto no necesariamente logra los mejores resultados para la retención de biota a nivel de paisaje cuando también consideramos la pérdida de hábitat en áreas fuera del sistema de AP. Aquí evaluamos las implicaciones que diferentes estrategias de expansión de AP pueden tener en la retención del hábitat de las especies en toda una región. Utilizando la retención de hábitat forestal para las 550 especies de aves dependientes de bosque de Colombia como nuestra variable de resultado, encontramos que cuando un mínimo del 30% del hábitat de cada especie es incluido en el sistema de AP, se observó que un patrón de expansión de AP dirigido a áreas con mayor riesgo de deforestación (prevención de riesgos) condujo a la retención, en promedio, de un 7.2% más de hábitat por especie para 2050 que un patrón enfocado en áreas con menor riesgo (evasión de riesgos). El enfoque de prevención de riesgos costó más por km2 de tierra conservada, pero fue más rentable para retener el hábitat en el paisaje (entre un 50% y un 69% menos costo por km2 de deforestación evitada). Para tener la misma eficacia en la prevención de la pérdida de hábitat en Colombia, el enfoque de evasión de riesgos requeriría más del doble de área protegida, lo que costaría tres veces más en el proceso. La expansión de las AP debería centrarse en las contribuciones de las AP a los resultados no sólo dentro de los propios sistemas de AP, sino en regiones enteras.


Assuntos
Biota , Florestas , Colômbia
15.
Glob Chang Biol ; 30(2): e17195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38389196

RESUMO

Scientific innovation is overturning conventional paradigms of forest, water, and energy cycle interactions. This has implications for our understanding of the principal causal pathways by which tree, forest, and vegetation cover (TFVC) influence local and global warming/cooling. Many identify surface albedo and carbon sequestration as the principal causal pathways by which TFVC affects global warming/cooling. Moving toward the outer latitudes, in particular, where snow cover is more important, surface albedo effects are perceived to overpower carbon sequestration. By raising surface albedo, deforestation is thus predicted to lead to surface cooling, while increasing forest cover is assumed to result in warming. Observational data, however, generally support the opposite conclusion, suggesting surface albedo is poorly understood. Most accept that surface temperatures are influenced by the interplay of surface albedo, incoming shortwave (SW) radiation, and the partitioning of the remaining, post-albedo, SW radiation into latent and sensible heat. However, the extent to which the avoidance of sensible heat formation is first and foremost mediated by the presence (absence) of water and TFVC is not well understood. TFVC both mediates the availability of water on the land surface and drives the potential for latent heat production (evapotranspiration, ET). While latent heat is more directly linked to local than global cooling/warming, it is driven by photosynthesis and carbon sequestration and powers additional cloud formation and top-of-cloud reflectivity, both of which drive global cooling. TFVC loss reduces water storage, precipitation recycling, and downwind rainfall potential, thus driving the reduction of both ET (latent heat) and cloud formation. By reducing latent heat, cloud formation, and precipitation, deforestation thus powers warming (sensible heat formation), which further diminishes TFVC growth (carbon sequestration). Large-scale tree and forest restoration could, therefore, contribute significantly to both global and surface temperature cooling through the principal causal pathways of carbon sequestration and cloud formation.


Assuntos
Sequestro de Carbono , Mudança Climática , Florestas , Planetas , Temperatura , Água , Temperatura Baixa , Árvores
16.
Malar J ; 23(1): 166, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807105

RESUMO

BACKGROUND: Deforestation is an important driver of malaria dynamics, with a relevant impact on mosquito ecology, including larval habitat availability, blood-feeding behaviour, and peak biting time. The latter is one of several entomological metrics to evaluate vectorial capacity and effectiveness of disease control. This study aimed to test the effect of forest cover percentage on the peak biting time of Plasmodium-uninfected and infected Nyssorhynchus darlingi females. METHODS: Mosquitoes were captured utilizing human landing catch (HLC) in the peridomestic habitat in field collections carried out in the wet, wet-dry transition, and dry seasons from 2014 to 2017 in areas with active malaria transmission in Amazonian Brazil. The study locations were in rural settlements in areas with the mean annual malaria parasite incidence (Annual Parasite Incidence, API ≥ 30). All Ny. darlingi females were tested for Plasmodium spp. infection using real time PCR technique. Forest cover percentage was calculated for each collection site using QGIS v. 2.8 and was categorized in three distinct deforestation scenarios: (1) degraded, < 30% forest cover, (2) intermediate, 30-70% forest cover, and (3) preserved, > 70% forest cover. RESULTS: The highest number of uninfected female Ny. darlingi was found in degraded landscape-sites with forest cover < 30% in any peak biting time between 18:00 and 0:00. Partially degraded landscape-sites, with (30-70%) forest cover, showed the highest number of vivax-infected females, with a peak biting time of 21:00-23:00. The number of P. falciparum-infected mosquitoes was highest in preserved sites with > 70% forest cover, a peak biting at 19:00-20:00, and in sites with 30-70% forest cover at 22:00-23:00. CONCLUSIONS: Results of this study show empirically that degraded landscapes favour uninfected Ny. darlingi with a peak biting time at dusk (18:00-19:00), whereas partially degraded landscapes affect the behaviour of Plasmodium-infected Ny. darlingi by shifting its peak biting time towards hours after dark (21:00-23:00). In preserved sites, Plasmodium-infected Ny. darlingi bite around dusk (18:00-19:00) and shortly after (19:00-20:00).


Assuntos
Comportamento Alimentar , Florestas , Mosquitos Vetores , Animais , Brasil , Feminino , Mosquitos Vetores/fisiologia , Mosquitos Vetores/parasitologia , Conservação dos Recursos Naturais , Mordeduras e Picadas de Insetos/epidemiologia , Estações do Ano , Malária/transmissão
17.
Ecol Appl ; 34(4): e2980, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38725332

RESUMO

Understanding how human-modified landscapes maintain biodiversity and provide ecosystem services is crucial for establishing conservation practices. Given that responses to land-use are species-specific, it is crucial to understand how land-use changes may shape patterns of species diversity and persistence in human-modified landscapes. Here, we used a comprehensive data set on bird distribution from the Brazilian Atlantic Forest to understand how species richness and individual occurrences of frugivorous bird species responded to land-use spatial predictors and, subsequently, assess how ecological traits and phylogeny modulated these responses. Using Bayesian hierarchical modeling, we reveal that the richness of frugivorous birds was positively associated with the amount of native forest and negatively with both agriculture and pasture amount at the landscape scale. Conversely, the effect of these predictors on species occurrence and ecological traits was highly variable and presented a weak phylogenetic signal. Furthermore, land-use homogenization (i.e., the conversion of forest to pasture or agriculture) led to pervasive consequences for forest-dependent bird species, whereas several generalist species thrived in deforested areas, replacing those sensitive to habitat disturbances.


Assuntos
Agricultura , Biodiversidade , Aves , Animais , Aves/fisiologia , Brasil , Clima Tropical , Conservação dos Recursos Naturais/métodos , Florestas , Frutas
18.
Ecol Appl ; : e3026, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39192366

RESUMO

Human activities have triggered profound changes in natural landscapes, resulting in species loss and disruption of pivotal ecological interactions such as insect herbivory. This antagonistic interaction is affected by complex pathways (e.g., abundance of herbivores and predators, plant chemical defenses, and resource availability), but the knowledge regarding how forest loss and fragmentation affect insect herbivory in human-modified tropical landscapes still remains poorly understood. In this context, we assessed multi-pathways by which changes in landscape structure likely influence insect herbivory in 20 Atlantic forest fragments in Brazil. Using path analysis, we estimated the direct effects of forest cover and forest edge density, and the indirect effect via canopy openness, number of understory plants and phenolic compounds, on leaf damage in understory plants located in the edge and interior of forest fragments. In particular, plants located in forest edges experienced greater leaf damage than interior ones. We observed that landscape edge density exerted a positive and direct effect on leaf damage in plants sampled at the edge of forest fragments. Our findings also indicated that forest loss and increase of edge density led to an increase in the canopy opening in the forest interior, which causes a reduction in the number of understory plants and, consequently, an increase in leaf damage. In addition, we detected that phenolic compounds negatively influence leaf damage in forest interior plants. Given the increasing forest loss in tropical regions, in which forest fragments become stranded in highly deforested, edge-dominated and degraded landscapes, our study highlights the pervasive enhancement in insect herbivory in remaining forest fragments-especially along forest edges and canopy gaps in the forest interior. As a result, increased herbivory is likely to affect forest regeneration and accelerate the ecological meltdown processes in these highly deforested and disturbed anthropogenic landscapes.

19.
Conserv Biol ; 38(4): e14245, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38456548

RESUMO

Understanding which species will be extirpated in the aftermath of large-scale human disturbance is critical to mitigating biodiversity loss, particularly in hyperdiverse tropical biomes. Deforestation is the strongest driver of contemporary local extinctions in tropical forests but may occur at different tempos. The 2 most extensive tropical forest biomes in South America-the Atlantic Forest and the Amazon-have experienced historically divergent pathways of habitat loss and biodiversity decay, providing a unique case study to investigate rates of local species persistence on a single continent. We quantified medium- to large-bodied mammal species persistence across these biomes to elucidate how landscape configuration affects their persistence and associated ecological functions. We collected occurrence data for 617 assemblages of medium- to large-bodied mammal species (>1 kg) in the Atlantic Forest and the Amazon. Analyzing natural habitat cover based on satellite data (1985-2022), we employed descriptive statistics and generalized linear models (GLMs) to investigate ecospecies occurrence patterns in relation to habitat cover across the landscapes. The subregional erosion of Amazonian mammal assemblage diversity since the 1970s mirrors that observed since the colonial conquest of the Atlantic Forest, given that 52.8% of all Amazonian mammals are now on a similar trajectory. Four out of 5 large mammals in the Atlantic Forest were prone to extirpation, whereas 53% of Amazonian mammals were vulnerable to extirpation. Greater natural habitat cover increased the persistence likelihood of ecospecies in both biomes. These trends reflected a median local species loss 63.9% higher in the Atlantic Forest than in the Amazon, which appears to be moving toward a turning point of forest habitat loss and degradation. The contrasting trajectories of species persistence in the Amazon and Atlantic Forest domains underscore the importance of considering historical habitat loss pathways and regional biodiversity erosion in conservation strategies. By focusing on landscape configuration and identifying essential ecological functions associated with large vertebrate species, conservation planning and management practices can be better informed.


Uso de la pérdida histórica de hábitat para predecir la desaparición de mamíferos contemporáneos en los bosques neotropicales Resumen Tener conocimiento de cuáles especies desaparecerán después de una perturbación humana es de suma importancia para mitigar la pérdida de la biodiversidad, particularmente en los biomas híper diversos. La deforestación es la principal causante de las extinciones locales contemporáneas en los bosques tropicales, aunque puede ocurrir en diferentes tiempos. Los dos bosques tropicales más extensos de América del Sur ­ el Bosque Atlántico y la Amazonia ­ han experimentado formas históricamente divergentes de pérdida de hábitat y decadencia de biodiversidad, lo que proporciona un caso único de estudio para investigar las tasas de persistencia de las especies locales en un solo continente. Cuantificamos la persistencia de las especies de mamíferos de talla mediana a grande en estos dos bosques para aclarar cómo la configuración del paisaje afecta su persistencia y las funciones ecológicas asociadas. Recolectamos datos de presencia de 617 ensambles de especies de mamíferos de talla mediana a grande (>1 kg) en el Bosque Atlántico y en la Amazonia. Analizamos la cobertura natural del hábitat con base en datos satelitales (1985­2022) y empleamos estadística descriptiva y modelos lineales generalizados (MLG) para investigar los patrones de presencia de las eco especies en relación con la cobertura del hábitat en los distintos paisajes. La erosión subregional de la diversidad de ensambles de mamíferos en la Amazonia desde los 70s es igual a la observada en el Bosque Atlántico desde la conquista colonial, dado que 52.8% de todos los mamíferos amazónicos se encuentran en una trayectoria similar. Cuatro de los cinco grandes mamíferos en el Bosque Atlántico estaban propensos a desaparecer, mientras que el 53% de los mamíferos amazónicos estaban vulnerables a desaparecer. Una mayor cobertura natural del hábitat incrementó la probabilidad de persistencia de las eco especies en ambos bosques. Estas tendencias reflejaron una pérdida mediana de especies locales 63.9% mayor en el Bosque Atlántico que en la Amazonia, lo cual parece dirigirse hacia un momento decisivo para la degradación y pérdida del hábitat del bosque. Las trayectorias contrastantes de la persistencia de especies en el Bosque Atlántico y la Amazonia destacan la importancia de considerar dentro de las estrategias de conservación las maneras en las que se ha perdido históricamente el hábitat y la erosión de la biodiversidad regional. Si nos enfocamos en la configuración del paisaje y en la identificación de las funciones ecológicas esenciales asociadas con las especies grandes de vertebrados, podemos informar de mejor manera a la planeación de la conservación y las prácticas de manejo.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Extinção Biológica , Florestas , Mamíferos , Animais , Mamíferos/fisiologia , Clima Tropical , Ecossistema , Brasil
20.
Conserv Biol ; 38(3): e14235, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38155500

RESUMO

The European Union Biodiversity Strategy 2030 (EUBDS) aims to regain biodiversity through enhanced forest conservation and protection, which may lead to increased timber harvest in non-EU countries. We aimed to identify the potential leakage of biodiversity risks as induced by the EUBDS. We created an indicator framework that allows one to quantify vulnerability of forest biodiversity. The framework is based on 26 biodiversity indicators for which indicator values were publicly available. We weighted single indicator values with countrywise modeled data on changed timber production under EUBDS implementation. Nearly 80% of the indicators pointed to higher vulnerability in the affected non-EU countries. Roundwood production was transferred to countries with, on average, lower governance quality (p = 0.0001), political awareness (p = 0.548), forest coverage (p = 0.034), and biomass (p = 0.272) and with less sustainable forest management (p = 0.044 and p = 0.028). These countries had more natural habitats (p = 0.039) and intact forest landscapes (p = 0.0001) but higher risk of species extinction (p = 0.006) and less protected area (p = 0.0001) than the EU countries. Only a few indicators pointed to lower vulnerability and biodiversity risks outside the EU. Safeguards are needed to ensure that implementation of EUBDS does not cause harm to ecosystems elsewhere. The EU regulation on deforestation-free supply chains might have limited effects because the sustainable management of existing and even expanding forests is not well considered. Sustained roundwood production in the EU is needed to avoid placing more pressure on more vulnerable ecosystems elsewhere. Decreasing species and habitat indicator values nevertheless call for global conservation and protection schemes. The EUBDS helped pave the way to the Kunming-Montreal Biodiversity Framework. Yet, lower values for the indicators mean governance and biodiversity engagement in non-EU countries suggest that this global framework might not sufficiently prevent leakage of risks to biodiversity. Effective land-use planning is necessary to balance conservation schemes with roundwood production.


Evaluación de la fuga de riesgos para la biodiversidad bajo la Estrategia de la Unión Europea sobre Biodiversidad 2030 Resumen La Estrategia de la Unión Europea sobre Biodiversidad 2030 (EEUSBD) busca recuperar la biodiversidad por medio de mejoras en la conservación y protección forestal, lo que podría derivar en un incremento en la producción maderera en los países que no pertenecen a la UE. Buscamos identificar la posible fuga de riesgos para la biodiversidad inducida por la EEUSBD. Creamos un marco indicador que permita cuantificar la vulnerabilidad de la biodiversidad forestal. El marco se basa en 26 indicadores de biodiversidad cuyos valores están disponibles al público. Ponderamos los valores de los indicadores individuales con datos modelados por países sobre los cambios en la producción maderera tras la aplicación de la EEUSBD. Casi el 80% de los indicadores señalaron un aumento de la vulnerabilidad en los países afectados que no pertenecen a la UE. La extracción forestal se transfirió a países que en promedio tienen menor calidad de gobierno (p = 0.0001), conciencia política (p = 0.548), cobertura forestal (p = 0.034) y biomasa (p = 0.272) y con un manejo forestal menos sustentable (p = 0.044 y p = 0.028). Estos países tienen más hábitats naturales (p = 0.039) y paisajes forestales intactos (p = 0.0001) pero un riesgo más elevado de extinción de especies (p = 0.006) y un área menos protegida (p = 0.0001) que los países de la UE. Sólo unos cuantos indicadores señalaron una reducción en la vulnerabilidad y los riesgos para la biodiversidad fuera de la UE. Se requieren salvaguardas para asegurar que la implementación de la EEUSBD no dañe los ecosistemas en otras partes. La regulación de la UE sobre las cadenas de producción libres de deforestación podría tener efectos limitados pues no se considera correctamente el manejo sustentable del bosque existente o en expansión. También se requiere una extracción forestal sostenida en la UE para evitar una mayor presión sobre otros ecosistemas vulnerables en otras localidades. Sin embargo, la reducción en los valores de los indicadores de especies y hábitat exige esquemas mundiales de conservación y protección. La EEUSBD ayudó a trazar el camino para el Marco Mundial de Biodiversidad de Kunming­Montreal, sin embargo, los valores más bajos de los indicadores de gobernanza y compromiso con la biodiversidad en países no pertenecientes a la UE sugieren que este marco global podría no prevenir efectivamente las fugas de riesgos para la biodiversidad. Es necesario planear eficientemente el uso de suelo para balancear los esquemas de conservación con la extracción forestal.


监测区域保护的治理和管理有效性早已被视为实现国家和全球生物多样性目标和实现适应性管理的重要基础。然而, 保护行动者(包括受治理和管理系统影响的人们)在实施保护活动和计划, 以及收集和利用治理和管理数据为跨时空尺度的决策提供信息的过程中, 仍面临重重阻碍。本文探讨了当前和过去为评估治理和管理有效性所做的努力、行动者在使用产出数据时面临的阻碍, 以及为保护决策提供信息的洞见。为了帮助克服这些阻碍, 我们开发了Elinor这一免费开源监测工具, 该工具以诺贝尔奖获得者Elinor Ostrom的研究成果为基础, 旨在促进不同治理和管理类型区域跨空间尺度的环境治理和管理数据的收集、存储、共享、分析和使用。本文介绍了与保护科学家和实践者共同设计和试用Elinor的过程, 以及其评估和在线数据系统的主要组成部分。我们还考虑了Elinor如何对现有方法进行补充, 包括:在单一评估中高水平地处理不同类型区域保护的治理和管理问题, 为数据收集提供灵活的选择, 以及整合数据系统与评估来支持不同空间尺度的数据使用和共享, 包括对《全球生物多样性框架》的全球监测。虽然挑战持续存在, 但Elinor的开发过程和工具本身为克服系统性收集和使用治理与管理数据中面临的阻碍提供了切实的解决方案。随着Elinor被更广泛地采用, 它将在实现更有效、更包容和更长期的基于区域的保护中发挥宝贵作用。【翻译:胡怡思;审校:聂永刚】.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , União Europeia , Conservação dos Recursos Naturais/métodos , Florestas , Agricultura Florestal
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