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1.
Protected areas (PAs) are a commonly used strategy to confront forest conversion and biodiversity loss. Although determining drivers of forest loss is central to conservation success, understanding of them is limited by conventional modeling assumptions. We used random forest regression to evaluate potential drivers of deforestation in PAs in Mexico, while accounting for nonlinear relationships and higher order interactions underlying deforestation processes. Socioeconomic drivers (e.g., road density, human population density) and underlying biophysical conditions (e.g., precipitation, distance to water, elevation, slope) were stronger predictors of forest loss than PA characteristics, such as age, type, and management effectiveness. Within PA characteristics, variables reflecting collaborative and equitable management and PA size were the strongest predictors of forest loss, albeit with less explanatory power than socioeconomic and biophysical variables. In contrast to previously used methods, which typically have been based on the assumption of linear relationships, we found that the associations between most predictors and forest loss are nonlinear. Our results can inform decisions on the allocation of PA resources by strengthening management in PAs with the highest risk of deforestation and help preemptively protect key biodiversity areas that may be vulnerable to deforestation in the future.  相似文献   

2.
Globally, deforestation continues, and although protected areas effectively protect forests, the majority of forests are not in protected areas. Thus, how effective are different management regimes to avoid deforestation in non‐protected forests? We sought to assess the effectiveness of different national forest‐management regimes to safeguard forests outside protected areas. We compared 2000–2014 deforestation rates across the temperate forests of 5 countries in the Himalaya (Bhutan, Nepal, China, India, and Myanmar) of which 13% are protected. We reviewed the literature to characterize forest management regimes in each country and conducted a quasi‐experimental analysis to measure differences in deforestation of unprotected forests among countries and states in India. Countries varied in both overarching forest‐management goals and specific tenure arrangements and policies for unprotected forests, from policies emphasizing economic development to those focused on forest conservation. Deforestation rates differed up to 1.4% between countries, even after accounting for local determinants of deforestation, such as human population density, market access, and topography. The highest deforestation rates were associated with forest policies aimed at maximizing profits and unstable tenure regimes. Deforestation in national forest‐management regimes that emphasized conservation and community management were relatively low. In India results were consistent with the national‐level results. We interpreted our results in the context of the broader literature on decentralized, community‐based natural resource management, and our findings emphasize that the type and quality of community‐based forestry programs and the degree to which they are oriented toward sustainable use rather than economic development are important for forest protection. Our cross‐national results are consistent with results from site‐ and regional‐scale studies that show forest‐management regimes that ensure stable land tenure and integrate local‐livelihood benefits with forest conservation result in the best forest outcomes.  相似文献   

3.
Abstract:  Many of the large, donor-funded community-based conservation projects that seek to reduce biodiversity loss in the tropics have been unsuccessful. There is, therefore, a need for empirical evaluations to identify the driving factors and to provide evidence that supports the development of context-specific conservation projects. We used a quantitative approach to measure, post hoc, the effectiveness of a US$19 million Integrated Conservation and Development Project (ICDP) that sought to reduce biodiversity loss through the development of villages bordering Kerinci Seblat National Park, a UNESCO World Heritage Site in Indonesia. We focused on the success of the ICDP component that disbursed a total of US$1.5 million through development grants to 66 villages in return for their commitment to stop illegally clearing the forest. To investigate whether the ICDP lowered deforestation rates in focal villages, we selected a subset of non-ICDP villages that had similar physical and socioeconomic features and compared their respective deforestation rates. Village participation in the ICDP and its development schemes had no effect on deforestation. Instead, accessible areas where village land-tenure had been undermined by the designation of selective-logging concessions tended to have the highest deforestation rates. Our results indicate that the goal of the ICDP was not met and, furthermore, suggest that both law enforcement inside the park and local property rights outside the park need to be strengthened. Our results also emphasize the importance of quantitative approaches in helping to inform successful and cost-effective strategies for tropical biodiversity conservation.  相似文献   

4.
There is profound interest in knowing the degree to which China's institutions are capable of protecting its natural forests and biodiversity in the face of economic and political change. China's 2 most important forest‐protection policies are its National Forest Protection Program (NFPP) and its national‐level nature reserves (NNRs). The NFPP was implemented in 2000 in response to deforestation‐caused flooding. We undertook the first national, quantitative assessment of the NFPP and NNRs to examine whether the NFPP achieved its deforestation‐reduction target and whether the NNRs deter deforestation altogether. We used MODIS data to estimate forest cover and loss across mainland China (2000–2010). We also assembled the first‐ever polygon dataset for China's forested NNRs (n = 237, 74,030 km2 in 2000) and used both conventional and covariate‐matching approaches to compare deforestation rates inside and outside NNRs (2000–2010). In 2000, 1.765 million km2 or 18.7% of mainland China was forested (12.3% with canopy cover of ≥70%)) or woodland (6.4% with canopy cover <70% and tree plus shrub cover ≥40%). By 2010, 480,203 km2 of forest and woodland had been lost, an annual deforestation rate of 2.7%. Forest‐only loss was 127,473 km2 (1.05% annually). In the NFPP provinces, the forest‐only loss rate was 0.62%, which was 3.3 times lower than in the non‐NFPP provinces. Moreover, the Landsat data suggest that these loss rates are overestimates due to large MODIS pixel size. Thus, China appears to have achieved, and even exceeded, its target of reducing deforestation to 1.1% annually in the NFPP provinces. About two‐thirds of China's NNRs were effective in protecting forest cover (prevented loss 4073 km2 unmatched approach; 3148 km2 matched approach), and within‐NNR deforestation rates were higher in provinces with higher overall deforestation. Our results indicate that China's existing institutions can protect domestic forest cover.  相似文献   

5.
Smallholder agriculture is the main driver of deforestation in the western Amazon, where terrestrial biodiversity reaches its global maximum. Understanding the biodiversity value of the resulting mosaics of cultivated and secondary forest is therefore crucial for conservation planning. However, Amazonian communities are organized across multiple forest types that support distinct species assemblages, and little is known about smallholder impacts across the range of forest types that are essential for sustaining biodiversity. We addressed this issue with a large-scale field inventory of birds (point counts) and trees (transects) in primary forest and smallholder agriculture in northern Peru across 3 forest types that are key for Amazonian biodiversity. For birds smallholder agriculture supported species richness comparable to primary forest within each forest type, but biotic homogenization across forest types resulted in substantial losses of biodiversity overall. These overall losses are invisible to studies that focus solely on upland (terra firma) forest. For trees biodiversity losses in upland forests dominated the signal across all habitats combined and homogenization across habitats did not exacerbate biodiversity loss. Proximity to forest strongly predicted the persistence of forest-associated bird and tree species in the smallholder mosaic, and because intact forest is ubiquitous in our study area, our results probably represent a best-case scenario for biodiversity in Amazonian agriculture. Land-use planning inside and outside protected areas should recognize that tropical smallholder agriculture has pervasive biodiversity impacts that are not apparent in typical studies that cover a single forest type. The full range of forest types must be surveyed to accurately assess biodiversity losses, and primary forests must be protected to prevent landscape-scale biodiversity loss.  相似文献   

6.
After their failure to achieve a significant reduction in the global rate of biodiversity loss by 2010, world governments adopted 20 new ambitious Aichi biodiversity targets to be met by 2020. Efforts to achieve one particular target can contribute to achieving others, but different targets may sometimes require conflicting solutions. Consequently, lack of strategic thinking might result, once again, in a failure to achieve global commitments to biodiversity conservation. We illustrate this dilemma by focusing on Aichi Target 11. This target requires an expansion of terrestrial protected area coverage, which could also contribute to reducing the loss of natural habitats (Target 5), reducing human‐induced species decline and extinction (Target 12), and maintaining global carbon stocks (Target 15). We considered the potential impact of expanding protected areas to mitigate global deforestation and the consequences for the distribution of suitable habitat for >10,000 species of forest vertebrates (amphibians, birds, and mammals). We first identified places where deforestation might have the highest impact on remaining forests and then identified places where deforestation might have the highest impact on forest vertebrates (considering aggregate suitable habitat for species). Expanding protected areas toward locations with the highest deforestation rates (Target 5) or the highest potential loss of aggregate species’ suitable habitat (Target 12) resulted in partially different protected area network configurations (overlapping with each other by about 73%). Moreover, the latter approach contributed to safeguarding about 30% more global carbon stocks than the former. Further investigation of synergies and trade‐offs between targets would shed light on these and other complex interactions, such as the interaction between reducing overexploitation of natural resources (Targets 6, 7), controlling invasive alien species (Target 9), and preventing extinctions of native species (Target 12). Synergies between targets must be identified and secured soon and trade‐offs must be minimized before the options for co‐benefits are reduced by human pressures.  相似文献   

7.
Protected Areas and Conservation of Biodiversity in the Tropics   总被引:7,自引:0,他引:7  
Abstract: We compared deforestation rates and the extent of fragmentation inside and outside protected areas in the Sarapiquí region of Costa Rica. We determined deforestation rates using remotely sensed images with supervised classification. We georeferenced the processed images and then transformed them to vector format for final mapping and parameter quantification. The deforestation rate in protected areas was low and declined sharply from 0.56% annually between 1976 and 1986 to 0.16% from 1991 to 1995. Outside the protected areas, the rate decreased from 3.6% in 1976–1986 to 2.8% in 1986–1991, but it increased again to 3.2% in 1991–1995. Fragmentation outside the protected areas increased considerably: the number of patches increased from 537 in 1976 to 1231 in 1996, while during the same period the average size of patches decreased from 0.95 to 0.25 km2. Forest landscapes in the Sarapiquí region are likely to lose considerable biodiversity because of the past forest loss and fragmentation even without further increases in deforestation and fragmentation.  相似文献   

8.
The potential impacts of payments for environmental services (PES) and protected areas (PAs) on environmental outcomes and local livelihoods in developing countries are contentious and have been widely debated. The available evidence is sparse, with few rigorous evaluations of the environmental and social impacts of PAs and particularly of PES. We measured the impacts on forests and human well‐being of three different PES programs instituted within two PAs in northern Cambodia, using a panel of intervention villages and matched controls. Both PES and PAs delivered additional environmental outcomes relative to the counterfactual: reducing deforestation rates significantly relative to controls. PAs increased security of access to land and forest resources for local households, benefiting forest resource users but restricting households’ ability to expand and diversify their agriculture. The impacts of PES on household well‐being were related to the magnitude of the payments provided. The two higher paying market‐linked PES programs had significant positive impacts, whereas a lower paying program that targeted biodiversity protection had no detectable effect on livelihoods, despite its positive environmental outcomes. Households that signed up for the higher paying PES programs, however, typically needed more capital assets; hence, they were less poor and more food secure than other villagers. Therefore, whereas the impacts of PAs on household well‐being were limited overall and varied between livelihood strategies, the PES programs had significant positive impacts on livelihoods for those that could afford to participate. Our results are consistent with theories that PES, when designed appropriately, can be a powerful new tool for delivering conservation goals whilst benefiting local people.  相似文献   

9.
A major question in global environmental policy is whether schemes to reduce carbon pollution through forest management, such as Reducing Emissions from Deforestation and Degradation (REDD+), can also benefit biodiversity conservation in tropical countries. We identified municipalities in Brazil that are priorities for reducing rates of deforestation and thus preserving carbon stocks that are also conservation targets for the endangered jaguar (Panthera onca) and biodiversity in general. Preliminary statistical analysis showed that municipalities with high biodiversity were positively associated with high forest carbon stocks. We used a multicriteria decision analysis to identify municipalities that offered the best opportunities for the conservation of forest carbon stocks and biodiversity conservation under a range of scenarios with different rates of deforestation and carbon values. We further categorized these areas by their representativeness of the entire country (through measures such as percent forest cover) and an indirect measure of cost (number of municipalities). The municipalities that offered optimal co‐benefits for forest carbon stocks and conservation were termed REDDspots (n = 159), and their spatial distribution was compared with the distribution of current and proposed REDD projects (n = 135). We defined REDDspots as the municipalities that offer the best opportunities for co‐benefits between the conservation of forest carbon stocks, jaguars, and other wildlife. These areas coincided in 25% (n = 40) of municipalities. We identified a further 95 municipalities that may have the greatest potential to develop additional REDD+ projects while also targeting biodiversity conservation. We concluded that REDD+ strategies could be an efficient tool for biodiversity conservation in key locations, especially in Amazonian and Atlantic Forest biomes. Identificación de Áreas en Brasil que Optimizan la Conservación del Carbono del Bosque, Jaguares y la Biodiversidad.  相似文献   

10.
The impacts of land‐use change on biodiversity in the Himalayas are poorly known, notwithstanding widespread deforestation and agricultural intensification in this highly biodiverse region. Although intact primary forests harbor many Himalayan birds during breeding, a large number of bird species use agricultural lands during winter. We assessed how Himalayan bird species richness, abundance, and composition during winter are affected by forest loss stemming from agriculture and grazing. Bird surveys along 12 elevational transects within primary forest, low‐intensity agriculture, mixed subsistence agriculture, and intensively grazed pastures in winter revealed that bird species richness and abundance were greatest in low‐intensity and mixed agriculture, intermediate in grazed pastures, and lowest in primary forest at both local and landscape scales; over twice as many species and individuals were recorded in low‐intensity agriculture than in primary forest. Bird communities in primary forests were distinct from those in all other land‐use classes, but only 4 species were unique to primary forests. Low‐, medium‐, and high‐intensity agriculture harbored 32 unique species. Of the species observed in primary forest, 80% had equal or greater abundance in low‐intensity agricultural lands, underscoring the value of these lands in retaining diverse community assemblages at high densities in winter. Among disturbed landscapes, bird species richness and abundance declined as land‐use intensity increased, especially in high‐intensity pastures. Our results suggest that agricultural landscapes are important for most Himalayan bird species in winter. But agricultural intensification—especially increased grazing—will likely result in biodiversity losses. Given that forest reserves alone may inadequately conserve Himalayan birds in winter, comprehensive conservation strategies in the region must go beyond protecting intact primary forests and ensure that low‐intensity agricultural lands are not extensively converted to high‐intensity pastures.  相似文献   

11.
There are concerns that Reduced Emissions from Deforestation and forest Degradation (REDD+) may fail to deliver potential biodiversity cobenefits if it is focused on high carbon areas. We explored the spatial overlaps between carbon stocks, biodiversity, projected deforestation threats, and the location of REDD+ projects in Indonesia, a tropical country at the forefront of REDD+ development. For biodiversity, we assembled data on the distribution of terrestrial vertebrates (ranges of amphibians, mammals, birds, reptiles) and plants (species distribution models for 8 families). We then investigated congruence between different measures of biodiversity richness and carbon stocks at the national and subnational scales. Finally, we mapped active REDD+ projects and investigated the carbon density and potential biodiversity richness and modeled deforestation pressures within these forests relative to protected areas and unprotected forests. There was little internal overlap among the different hotspots (richest 10% of cells) of species richness. There was also no consistent spatial congruence between carbon stocks and the biodiversity measures: a weak negative correlation at the national scale masked highly variable and nonlinear relationships island by island. Current REDD+ projects were preferentially located in areas with higher total species richness and threatened species richness but lower carbon densities than protected areas and unprotected forests. Although a quarter of the total area of these REDD+ projects is under relatively high deforestation pressure, the majority of the REDD+ area is not. In Indonesia at least, first‐generation REDD+ projects are located where they are likely to deliver biodiversity benefits. However, if REDD+ is to deliver additional gains for climate and biodiversity, projects will need to focus on forests with the highest threat to deforestation, which will have cost implications for future REDD+ implementation.  相似文献   

12.
Effects of Coffee Management on Deforestation Rates and Forest Integrity   总被引:1,自引:0,他引:1  
Knowledge about how forest margins are utilized can be crucial for a general understanding of changes in forest cover, forest structure, and biodiversity across landscapes. We studied forest‐agriculture transitions in southwestern Ethiopia and hypothesized that the presence of coffee (Coffea arabica)decreases deforestation rates because of coffee's importance to local economies and its widespread occurrence in forests and forest margins. Using satellite images and elevation data, we compared changes in forest cover over 37 years (1973–2010) across elevations in 2 forest‐agriculture mosaic landscapes (1100 km2 around Bonga and 3000 km2 in Goma‐Gera). In the field in the Bonga area, we determined coffee cover and forest structure in 40 forest margins that differed in time since deforestation. Both the absolute and relative deforestation rates were lower at coffee‐growing elevations compared with at higher elevations (?10/20% vs. ?40/50% comparing relative rates at 1800 m asl and 2300–2500 m asl, respectively). Within the coffee‐growing elevation, the proportion of sites with high coffee cover (>20%) was significantly higher in stable margins (42% of sites that had been in the same location for the entire period) than in recently changed margins (0% of sites where expansion of annual crops had changed the margin). Disturbance level and forest structure did not differ between sites with 30% or 3% coffee. However, a growing body of literature on gradients of coffee management in Ethiopia reports coffee's negative effects on abundances of forest‐specialist species. Even if the presence of coffee slows down the conversion of forest to annual‐crop agriculture, there is a risk that an intensification of coffee management will still threaten forest biodiversity, including the genetic diversity of wild coffee. Conservation policy for Ethiopian forests thus needs to develop strategies that acknowledge that forests without coffee production may have higher deforestation risks than forests with coffee production and that forests with coffee production often have lower biodiversity value. Efectos de la Administración Cafetalera sobre las Tasas de Deforestación y la Integridad de los Bosques  相似文献   

13.
The effectiveness of parks for forest conservation is widely debated in Africa, where increasing human pressure, insufficient funding, and lack of management capacity frequently place significant demands on forests. Tropical forests house a substantial portion of the world's remaining biodiversity and are heavily affected by anthropogenic activity. We analyzed park effectiveness at the individual (224 parks) and national (23 countries) level across Africa by comparing the extent of forest loss (as a proxy for deforestation) inside parks to matched unprotected control sites. Although significant geographical variation existed among parks, the majority of African parks had significantly less forest loss within their boundaries (e.g., Mahale Park had 34 times less forest loss within its boundary) than control sites. Accessibility was a significant driver of forest loss. Relatively inaccessible areas had a higher probability (odds ratio >1, p < 0.001) of forest loss but only in ineffective parks, and relatively accessible areas had a higher probability of forest loss but only in effective parks. Smaller parks less effectively prevented forest loss inside park boundaries than larger parks (T = ?2.32, < 0.05), and older parks less effectively prevented forest loss inside park boundaries than younger parks (F2,154 = ?4.11, < 0.001). Our analyses, the first individual and national assessment of park effectiveness across Africa, demonstrated the complexity of factors (such as geographical variation, accessibility, and park size and age) influencing the ability of a park to curb forest loss within its boundaries.  相似文献   

14.
Political transitions often trigger substantial environmental changes. In particular, deforestation can result from the complex interplay among the components of a system—actors, institutions, and existing policies—adapting to new opportunities. A dynamic conceptual map of system components is particularly useful for systems in which multiple actors, each with different worldviews and motivations, may be simultaneously trying to alter different facets of the system, unaware of the impacts on other components. In Myanmar, a global biodiversity hotspot with the largest forest area in mainland Southeast Asia, ongoing political and economic reforms are likely to change the dynamics of deforestation drivers. A fundamental conceptual map of these dynamics is therefore a prerequisite for interventions to reduce deforestation. We used a system‐dynamics approach and causal‐network analysis to determine the proximate causes and underlying drivers of forest loss and degradation in Myanmar from 1995 to 2016 and to articulate the linkages among them. Proximate causes included infrastructure development, timber extraction, and agricultural expansion. These were stimulated primarily by formal agricultural, logging, mining, and hydropower concessions and economic investment and social issues relating to civil war and land tenure. Reform of land laws, the link between natural resource extraction and civil war, and the allocation of agricultural concessions will influence the extent of future forest loss and degradation in Myanmar. The causal‐network analysis identified priority areas for policy interventions, for example, creating a public registry of land‐concession holders to deter corruption in concession allocation. We recommend application of this analytical approach to other countries, particularly those undergoing political transition, to inform policy interventions to reduce forest loss and degradation.  相似文献   

15.
There is current debate about the potential for secondary regrowth to rescue tropical forests from an otherwise inevitable cascade of biodiversity loss due to land clearing and scant evidence to test how well active restoration may accelerate recovery. We used site chronosequences to compare developmental trajectories of vegetation between self‐organized (i.e., spontaneous) forest regrowth and biodiversity plantings (established for ecological restoration, with many locally native tree species at high density) in the Australian wet tropics uplands. Across 28 regrowth sites aged 1–59 years, some structural attributes reached reference rainforest levels within 40 years, whereas wood volume and most tested components of native plant species richness (classified by species’ origins, family, and ecological functions) reached less than 50% of reference rainforest values. Development of native tree and shrub richness was particularly slow among species that were wind dispersed or animal dispersed with large (>10 mm) seeds. Many species with animal‐dispersed seeds were from near‐basal evolutionary lineages that contribute to recognized World Heritage values of the study region. Faster recovery was recorded in 25 biodiversity plantings of 1–25 years in which wood volume developed more rapidly; native woody plant species richness reached values similar to reference rainforest and was better represented across all dispersal modes; and species from near‐basal plant families were better (although incompletely) represented. Plantings and regrowth showed slow recovery in species richness of vines and epiphytes and in overall resemblance to forest in species composition. Our results can inform decision making about when and where to invest in active restoration and provide strong evidence that protecting old‐growth forest is crucially important for sustaining tropical biodiversity.  相似文献   

16.
Abstract:  Deforestation in Indonesia poses a significant threat to the region's biodiversity. We mapped forest cover in Kalimantan, Indonesia, in 2002, with imagery provided by the Moderate Resolution Imaging Spectrometer (MODIS). The MODIS-based forest and nonforest map showed good agreement with other sources of recent data on forest cover. Comparison of MODIS forest cover with Indonesian government data from 1996 revealed that almost 3 million ha of forest were lost in Kalimantan since the major El Niño event of 1997–1998, when a drought produced unprecedented biomass burning in the region. Over two-thirds of the deforestation occurred in proposed and existing protected areas, especially those of 100,000–250,000 ha. The loss of forest in proposed and existing protected areas suggests that Kalimantan's protected-area network is no longer viable and that alternative conservation strategies, such as timber certification and improved monitoring and enforcement, are needed to preserve remaining forest habitats there.  相似文献   

17.
Deforestation in Brazilian Amazonia: History, Rates, and Consequences   总被引:17,自引:0,他引:17  
Abstract:  Brazil's Amazon forest remained largely intact until the "modern" era of deforestation began with the inauguration of the Transamazon Highway in 1970. Amazonian deforestation rates have trended upward since 1991, with clearing proceeding at a variable but rapid pace. Although Amazonian forests are cut for various reasons, cattle ranching predominates. The large and medium-sized ranches account for about 70% of clearing activity. Profit from beef cattle is only one of the income sources that make deforestation profitable. Forest degradation results from logging, ground fires (facilitated by logging), and the effects of fragmentation and edge formation. Degradation contributes to forest loss. The impacts of deforestation include loss of biodiversity, reduced water cycling (and rainfall), and contributions to global warming. Strategies to slow deforestation include repression through licensing procedures, monitoring, and fines. The severity of penalties for deforestation needs to be sufficient to deter illegal clearing but not so great as to be unenforceable. Policy reform is also needed to address root causes of deforestation, including the role of clearing in establishing land claims.  相似文献   

18.
We developed and tested patch occupancy models for an endemic understory bird with limited dispersal ability, the Chucao Tapaculo (Scelorchilus rubecula), in two South American temperate rain forest landscapes that differed in levels and duration of forest loss. We assessed cover changes since 1961 in each landscape and surveyed patches for Chucao Tapaculo occupancy. We then developed incidence-based predictive models independently for each landscape and tested each model reciprocally in the alternative study area. We thereby assessed the domain of model applicability and identified those predictor variables with general effects and those that varied between the two landscapes. The two models were consistent regarding variable selection, and predictive accuracy of each model was high in the landscape where training data were collected. However, the models differed substantially in the magnitudes of effects related to patch size, with larger unoccupied patches observed in the landscape with the more advanced stage of fragmentation. Due to this discrepancy, each model performed poorly when applied to the alternative landscape, potentially reflecting the contrasting stages of habitat loss. Although it was impossible to dissociate effects of level and duration of forest loss, we viewed the landscapes as representing two extremes along a continuum of fragmentation, providing insights into potential trajectories for portions of the biome where deforestation is occurring. Further, our data suggest that static equilibrium models developed from distribution patterns in recently fragmented landscapes may overestimate persistence when used as a forecasting tool, or when extrapolated to alternative landscapes where fragmentation is more advanced. Thus, we suggest that landscapes used as standards for model building should be selected with caution. We recommend that distribution patterns be obtained from landscapes where fragmentation is advanced, preferably with histories of fragmentation long enough that time-delayed extinctions already would have occurred.  相似文献   

19.
Trade‐offs in ecosystem services (ES) have received increasing attention because provisioning services often come at the expense of biodiversity loss. When land‐use patterns are not maximally efficient relative to productivity, provisioning services, such as crop production, can often be increased without losing biodiversity. The Atlantic Forest (AF) encompasses dense, mixed, and seasonal forests and has high levels of endemism and anthropogenic threat. We examined trade‐offs between biodiversity and crop production in the AF to provide insights into land‐use management decisions. We developed a biodiversity metric that combines information on tree species richness, evolutionary distinctiveness, and rarity at the local level. We examined the extent to which the nature of ES trade‐offs differ among the 3 forest types. We assessed how annual deforestation rates and land management practices affect biodiversity and agricultural revenues. Finally, we tested whether it is possible to achieve the same total regional revenue without reducing biodiversity by improving local management practices. The 3 forest types had similar patterns in ES trade‐offs, although within mixed forest patterns differed. Biodiversity appeared to be more sensitive to land‐use change than crop revenues. Certain crops yielded up to 10 times higher values in some sites. Enhanced crop productivity may increase revenues without reducing biodiversity. Our results showed that to enhance human well‐being without further conversion of AF, maximizing crop productivity is needed . Increasing efficiency of management outcomes by maintaining higher biodiversity and increasing provisioning services depends on knowledge of forest type, the comparative advantage of planting crops in the best places, and preserving species in a balanced manner across forests.  相似文献   

20.
Offsets are a novel conservation tool, yet using them to achieve no net loss of biodiversity is challenging. This is especially true when using conservation offsets (i.e., protected areas) because achieving no net loss requires avoiding equivalent loss. Our objective was to determine if offsetting the impacts of mining achieves no net loss of native vegetation in Brazil's largest iron mining region. We used a land‐use change model to simulate deforestation by mining to 2020; developed a model to allocate conservation offsets to the landscape under 3 scenarios (baseline, no new offsets; current practice, like‐for‐like [by vegetation type] conservation offsetting near the impact site; and threat scenario, like‐for‐like conservation offsetting of highly threatened vegetation); and simulated nonmining deforestation to 2020 for each scenario to quantify avoided deforestation achieved with offsets. Mines cleared 3570 ha of native vegetation by 2020. Under a 1:4 offset ratio, mining companies would be required to conserve >14,200 ha of native vegetation, doubling the current extent of protected areas in the region. Allocating offsets under current practice avoided deforestation equivalent to 3% of that caused by mining, whereas allocating under the threat scenario avoided 9%. Current practice failed to achieve no net loss because offsets did not conserve threatened vegetation. Explicit allocation of offsets to threatened vegetation also failed because the most threatened vegetation was widely dispersed across the landscape, making conservation logistically difficult. To achieve no net loss with conservation offsets requires information on regional deforestation trajectories and the distribution of threatened vegetation. However, in some regions achieving no net loss through conservation may be impossible. In these cases, other offsetting activities, such as revegetation, will be required. Compensación de los Impactos de la Minería para Obtener Ninguna Pérdida Neta de la Vegetación Nativa  相似文献   

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