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1.
Climate change and land use conversion are global threats to biodiversity. Protected areas and biological corridors have been historically implemented as biodiversity conservation measures and suggested as tools within planning frameworks to respond to climate change. However, few applications to national protected areas systems considering climate change in tropical countries exist. Our goal is to define new priority areas for biodiversity conservation and biological corridors within an existing protected areas network. We aim at preserving samples of all biodiversity under climate change and facilitate species dispersal to reduce the vulnerability of biodiversity. The analysis was based on a three step strategy: i) protect representative samples of various levels of terrestrial biodiversity across protected area systems given future redistributions under climate change, ii) identify and protect areas with reduced climate velocities where populations could persist for relatively longer periods, and iii) ensure species dispersal between conservation areas through climatic connectivity pathways. The study was integrated into a participatory planning approach for biodiversity conservation in Costa Rica. Results showed that there should be an increase of 11 % and 5 % on new conservation areas and biological corridors respectively. Our approach integrates climate change into the design of a network of protected areas for tropical ecosystems and can be applied to other biodiversity rich areas to reduce the vulnerability of biodiversity to global warming.  相似文献   

2.
Protected areas are increasingly prone to violent extremism spillover, with dramatic consequences for both local people and wildlife populations. Due to the influence of violent extremist groups, science and policy generally fade away. We outline the case of the W-Arly-Pendjari complex of protected areas in West Africa (Burkina Faso, Benin, and Niger), 62% of which is currently under the control of violent extremist groups. The last large population of West African elephants may soon disappear if no action is taken. We discuss the roles of conservation science and policy in protected areas under violent extremism spillover, namely (i) maintaining and reinforcing international support, (ii) authentically engaging local communities in conservation and management strategies, and (iii) planning long-term conservation and security strategies.  相似文献   

3.
With protected areas identified as the primary tool to halt the loss of biodiversity, the Convention on Biological Diversity has set targets for protected area expansion. Increasingly, concerns are being raised that target-driven growth, where targets focus largely on quantity (total area protected) rather than quality, may fail to achieve their intended biodiversity outcomes. Therefore, it is important to assess whether growth in area protected is translating into a more robust system of protected areas that better safeguard biodiversity. In this study, we propose a set of seven indicators, drawing on the body of evidence for the elements of protected area design and management associated with better biodiversity outcomes. Many of the features of effective design and management interact with one another, making it essential to use a suite of indicators and consider progress relative to trends across all of these indicators. We implemented the proposed indicators for the Australian National Reserve System, which has undergone significant growth over the past two decades. Our findings demonstrate that relying on trends in total area protected can obscure negative trends in other important indicators which suggest many protected areas in Australia are under increasing pressure. Meanwhile, the level of resourcing for management has not kept pace with increases in total area protected and has certainly not scaled with changes in pressures on protected areas. It is important that the global conservation community strive for a more nuanced set of indicators for conservation progress to identify whether growth in area protected has, or has not, translated into a more robust and effective system of protected areas. Given that most of the indicators we propose can be populated with existing data, we believe this approach could be achievable for protected areas globally.  相似文献   

4.
Human-driven changes in the global environment pose an increasingly urgent challenge for the management of ecosystems that is made all the more difficult by the uncertain future of both environmental conditions and ecological responses. Land managers need strategies to increase regional adaptive capacity, but relevant and rapid assessment approaches are lacking. To address this need, we developed a method to assess regional protected area networks across biophysically important climatic gradients often linked to biodiversity and ecosystem function. We plot the land of the southwestern United States across axes of historical climate space, and identify landscapes that may serve as strategic additions to current protected area portfolios. Considering climate space is straightforward, and it can be applied using a variety of relevant climate parameters across differing levels of land protection status. The resulting maps identify lands that are climatically distinct from existing protected areas, and may be utilized in combination with other ecological and socio-economic information essential to collaborative landscape-scale decision-making. Alongside other strategies intended to protect species of special concern, natural resources, and other ecosystem services, the methods presented herein provide another important hedging strategy intended to increase the adaptive capacity of protected area networks.  相似文献   

5.
Protected areas are currently the primary strategy employed worldwide to maintain ecosystem services and mitigate biodiversity loss. Despite the prevalence and planned expansion of protected areas, the impact of this conservation tool on human communities remains hotly contested in conservation policy. The social impacts of protected areas are poorly understood largely because previous evaluations have tended to focus on one or very few outcomes, and few have had the requisite data to assess causal effects (i.e. longitudinal data for protected and control sites). Here, we evaluated the short-, medium- and long-term impacts of marine protected areas (MPAs) that were specifically designed to achieve the dual goals of conservation and poverty alleviation (hereafter “integrated MPAs”), on three key domains of poverty (security, opportunity and empowerment) in eight villages in North Sulawesi, Indonesia. Using social data for villages with and without integrated MPAs from pre-, mid- and post-the five-year implementation period of the integrated MPAs, we found that the integrated MPAs appeared to contribute to poverty alleviation. Positive impacts spanned all three poverty domains, but within each domain the magnitude of the effects and timescales over which they manifested were mixed. Importantly, positive impacts appeared to occur mostly during the implementation period, after which integrated MPA activities all but ceased and reductions in poverty did not continue to accrue. This finding questions the efficiency of the short-term approach taken in many international donor-assisted protected area projects that integrate development and conservation, which are often designed with the expectation that project activities will be sustained and related benefits will continue to accumulate after external support is terminated.  相似文献   

6.
利用1967年航片数据、1986和2000年两期遥感TM数据,对长江黄河源区高寒生态系统分布格局变化进行了分析,并结合源区气候变化观测数据,分析了源区高寒生态系统变化与气候的关系和陆面生态系统变化对源区水文过程的影响。结果表明:过去40 a来,长江源区高覆盖草甸、高覆盖草原和湿地面积分别减少了13.5%、3.6%和28.9%,黄河源区高覆盖草甸、高覆盖草原和湿地面积分别减少了23.2%、7.0%和13.6%,江河源区低覆盖草甸、草原和沙漠草地面积均不同程度地增加;长江、黄河源区气温变化率分别为0.27和0.31℃/10a,降水的变化趋势在长江、黄河源区分别以0.36和0.07 mm/a的速率递增,气温持续升高和由此引起的冻土退化是导致高寒生态系统退化的主要因素之一;陆面生态系统退化对源区水文过程影响显著,在降水没有明显变化的情况下,长江、黄河源区径流系数分别由1960年代的0.16和0.28下降到21世纪的0.12和0.21,且降水-径流关系减弱,出源径流趋于减少,洪水发生频率显著增加,水源涵养指数持续减小。如何应对气候变化,维护源区高寒生态系统功能,已成为迫切需要关注和解决的关键问题。  相似文献   

7.
Large marine protected areas are increasingly being established to meet global conservation targets and promote sustainable use of resources. Although the factors affecting the performance of small-scale marine protected areas are relatively well studied, there is no such body of knowledge for large marine protected areas. We conducted a global meta-analysis to systematically investigate social, ecological, and governance characteristics of successful large marine protected areas with respect to several social and ecological outcomes. We included all large (>10,000 km2), implemented (>5 years of active management) marine protected areas that had sufficient data for analysis, for a total of twelve cases. We used the Social-Ecological Systems Meta-Analysis Database, and a consistent protocol for using secondary data and key informant interviews, to code proxies for fisheries, ecosystem health, and the wellbeing of user groups (mainly fishers). We tested four sets of hypotheses derived from the literature on small-scale marine protected areas and common-pool resources: (i) the attributes of species and ecosystems to be managed in the marine protected area, (ii) adherence to principles for designing small-scale marine protected areas, (iii) adherence to the design principles for common-pool resource management, and (iv) stakeholder participation. We found varying levels of support for these hypotheses. Improved fisheries were associated with older marine protected areas, and higher levels of enforcement. Declining fisheries were associated with several ecological and economic factors, including low productivity, high mobility, and high market value. High levels of participation were correlated with improvements in wellbeing and ecosystem health trends. Overall, this study constitutes an important first step in identifying factors affecting social wellbeing and ecological performance of large marine protected areas.  相似文献   

8.
This paper investigates the equity implications of marketing ecosystem services in protected areas and rural communities. We use a three-tiered equity framework to analyse four distinct efforts to commercialise watershed recharge and carbon dioxide fixation by forests in Meso-America. We show that project development and participation are strongly mediated by organisational networks, as well as existing rights of access over land and forest resources. We demonstrate that procedural fairness diverges strongly when initiatives are implemented in protected areas or in rural communities. While in the former reserve managers and intermediaries concentrate all decision-making power, initiatives working with rural communities are able to integrate more significantly service providers in management decisions. Marketing ecosystem services in protected areas contributes to reduce expenditure rates for protected area management, but also results in less equitable outcomes, as rural communities and forest resource users become excluded from receiving sustained development benefits. When ecosystem services are commercialised by rural farmers, payments do not cover opportunity costs but act as a significant incentive for participation in most cases. Ecosystem service providers also benefit from complementary project activities, such as forest management training and agricultural extension support. We argue that limited economic impact and existing inequities in decision-making and outcomes can be explained by problems of institutional design, in particular the inability of markets and payments for ecosystem services to account for context-related factors, such as property rights.  相似文献   

9.
A significant challenge in resource management is addressed: the perceived trade-off between economic growth and ecosystem restoration and conservation. Traditional approaches to management regard restoration as a potential cost to economic productivity. In this study we show that by considering a broader range of economic values, including ecosystem services values, an argument can be made that restoration of lake ecosystems also leads to favourable economic outcomes when commonly disregarded values are considered. Our case study analyses the ecological outcomes of different catchment mitigation and land use scenarios in terms of water quality results in a lake, assessing changes in land use values based on opportunity costs, and ecosystem services values. We show that when considering the value of ecosystem services, intensive agricultural land use is not necessarily the most economically valuable form of land use within a lake catchment. Indeed, a shift towards alternative land uses within a catchment can lead to both ongoing economic benefits and improvements in water quality. In this context, land-use change offers an option for water quality improvement that minimises lake and land mitigation costs, while adding value to catchment land use. An argument is made supporting land use change towards indigenous forest types, which can sustain alternative sources of income such as a range of recreational values, while supporting important ecosystem functions for the region.  相似文献   

10.
Vast areas of rangelands across the world are grazed with increasing intensity, but interactions between livestock production, biodiversity and other ecosystem services are poorly studied. This study explicitly determines trade-offs and synergies between ecosystem services and livestock grazing intensity on rangelands. Grazing intensity and its effects on forage utilization by livestock, carbon sequestration, erosion prevention and biodiversity are quantified and mapped, using global datasets and models. Results show that on average 4% of the biomass produced annually is consumed by livestock. On average, erosion prevention is 10% lower in areas with a high grazing intensity compared to areas with a low grazing intensity, whereas carbon emissions are more than four times higher under high grazing intensity compared to low grazing intensity. Rangelands with the highest grazing intensity are located in the Sahel, Pakistan, West India, Middle East, North Africa and parts of Brazil. These high grazing intensities result in carbon emissions, low biodiversity values, low capacity for erosion prevention and unsustainable forage utilization. Although the applied models simplify the processes of ecosystem service supply, our study provides a global overview of the consequences of grazing for biodiversity and ecosystem services. The expected increasing future demand for livestock products likely increase pressures on rangelands. Global-scale models can help to identify targets and target areas for international policies aiming at sustainable future use of these rangelands.  相似文献   

11.
Using recent land cover maps, we used matching techniques to analyze forest cover and assess effectiveness in avoiding deforestation in three main land tenure regimes in Panama, namely protected areas, indigenous territories and non-protected areas. We found that the tenure status of protected areas and indigenous territories (including comarcas and claimed lands) explains a higher rate of success in avoided deforestation than other land tenure categories, when controlling for covariate variables such us distance to roads, distance to towns, slope, and elevation. In 2008 protected areas and indigenous territories had the highest percentage of forest cover and together they hosted 77% of Panama's total mature forest area. Our study shows the promises of matching techniques as a potential tool for demonstrating and quantifying conservation efforts. We therefore propose that matching could be integrated to methodological approaches allowing compensating forests’ protectors. Because conserving forest carbon stocks in forested areas of developing countries is an essential component of REDD+ and its future success, the discussion of our results is relevant to countries or jurisdictions with high forest cover and low deforestation rates.  相似文献   

12.
Agricultural suitability maps are a key input for land use zoning and projections of cropland expansion. Suitability assessments typically consider edaphic conditions, climate, crop characteristics, and sometimes incorporate accessibility to transportation and market infrastructure. However, correct weighting among these disparate factors is challenging, given rapid development of new crop varieties, irrigation, and road networks, as well as changing global demand for agricultural commodities. Here, we compared three independent assessments of cropland suitability to spatial and temporal dynamics of agricultural expansion in the Brazilian state of Mato Grosso during 2001–2012. We found that areas of recent cropland expansion identified using satellite data were generally designated as low to moderate suitability for rainfed crop production. Our analysis highlighted the abrupt nature of suitability boundaries, rather than smooth gradients of agricultural potential, with little additional cropland expansion beyond the extent of the flattest areas (0–2% slope). Satellite-based estimates of the interannual variability in the use of existing crop areas also provided an alternate means to assess suitability. On average, cropland areas in the Cerrado biome had higher utilization (84%) than croplands in the Amazon region of northern Mato Grosso (74%). Areas of more recent expansion had lower utilization than croplands established before 2002, providing empirical evidence for lower suitability or alternative management strategies (e.g., pasture–soya rotations) for lands undergoing more recent land use transitions. This unplanted reserve constitutes a large area of potentially available cropland (PAC) without further expansion, within the management limits imposed for pest management and fallow cycles. Using two key constraints on future cropland expansion, slope and restrictions on further deforestation of Amazon or Cerrado vegetation, we found little available flat land for further legal expansion of crop production in Mato Grosso. Dynamics of cropland expansion from more than a decade of satellite observations indicated narrow ranges of suitability criteria, restricting PAC under current policy conditions, and emphasizing the advantages of field-scale information to assess suitability and utilization.  相似文献   

13.
Under natural conditions, balanced ecological systems develop in which the soil is protected by a cover of different plants. When man modifies the environment, in his attempts to produce more food, fiber and fuel, the ecological system is changed.This often results in the soil being exposed to the processes of accelerated water erosion. In this way, millions of hectares of land, particularly in the semi arid areas are now eroding.This paper stresses that the most important principle in controlling water erosion is to develop a new balanced system which is not only productive but which is also stable.Water erosion control schemes should therefore be based on the selection and introduction of correct land use.Examples are given of the types of measures that may be needed for cultivated, grazing and forestry lands.In some cases, a change in land use may also have to be supported by the construction of physical conservation measures. Some common examples of such measures are briefly described.  相似文献   

14.
The aim of this study was to generate a land productivity dynamics (LPD) map of a degraded catchment located in sub-humid terrestrial ecosystem via a land degradation assessment using three indicators, namely land use and land cover, land productivity, and soil organic carbon density. The study was carried out in two adjacent microcatchments located in Gediz River Basin and conducted between 2001 and 2015. For this purpose, Landsat satellite images were used to determine changing of land use and land cover and vegetation density. In addition, 319 soil samples were collected from surface and subsurface soil depths to detect soil organic carbon density of the study area in May 2015. According to the study results, in more than 23% of the catchments’ area of approx. 3896 ha, land productivity is observed to decline while about 24% shows early signs of decline level. Some of these areas used under agricultural cropping, overgrazed pasture, and artificial areas showed evidence of soil erosion problem. Only very small area of the catchment shows stable and increasing land productivity dynamics trend during the 14-year period.  相似文献   

15.
The first decade of the new millennium saw a boom in rubber prices. This led to rapid and widespread land conversion to monoculture rubber plantations in continental SE Asia, where natural rubber production has increased >50% since 2000. Here, we analyze the subsequent spread of rubber between 2005 and 2010 in combination with environmental data and reports on rubber plantation performance. We show that rubber has been planted into increasingly sub-optimal environments. Currently, 72% of plantation area is in environmentally marginal zones where reduced yields are likely. An estimated 57% of the area is susceptible to insufficient water availability, erosion, frost, or wind damage, all of which may make long-term rubber production unsustainable. In 2013 typhoons destroyed plantations worth US$ >250 million in Vietnam alone, and future climate change is likely to lead to a net exacerbation of environmental marginality for both current and predicted future rubber plantation area. New rubber plantations are also frequently placed on lands that are important for biodiversity conservation and ecological functions. For example, between 2005 and 2010 >2500 km2 of natural tree cover and 610 km2 of protected areas were converted to plantations. Overall, expansion into marginal areas creates potential for loss-loss scenarios: clearing of high-biodiversity value land for economically unsustainable plantations that are poorly adapted to local conditions and alter landscape functions (e.g. hydrology, erosion) – ultimately compromising livelihoods, particularly when rubber prices fall.  相似文献   

16.
Protected areas (PAs) serve as a critical strategy for protecting natural resources, conserving biodiversity, and mitigating climate change. While there is a critical need to guide area-based conservation efforts, a systematic assessment of PA effectiveness for storing carbon stocks has not been possible due to the lack of globally consistent forest biomass data. In this study, we present a new methodology utilizing forest structural information and aboveground biomass density (AGBD) obtained from the Global Ecosystem Dynamics Investigation (GEDI) mission. We compare PAs with similar, unprotected forests obtained through statistical matching to assess differences in carbon storage and forest structure. We also assess matching outcomes for a robust and minimally biased way to quantify PA efficacy. We find that all analyzed PAs in Tanzania possess higher biomass densities than their unprotected counterfactuals (24.4% higher on average). This is also true for other forest structure metrics, including tree height, canopy cover, and plant area index (PAI). We also find that community-governed PAs are the most effective category of PAs at preserving forest structure and AGBD – often outperforming those managed by international or national entities. In addition, PAs designated under more than one entity perform better than the PAs with a single designation, especially those with multiple international designations. Finally, our findings suggest that smaller PAs may be more effective for conservation, depending on levels of connectivity. Taken together, these findings support the designation of PAs as an effective means for forest management with considerable potential to protect forest ecosystems and achieve long-term climate goals.  相似文献   

17.
Given current land degradation trends, Land Degradation Neutrality (LDN, SDG Target 15.3) by 2030 could be difficult to attain. Solutions to avoid, reduce, and reverse land degradation are not being implemented at sufficiently large scales, pointing to land governance as the main obstacle. In this paper, we review dynamics in agricultural land governance, and the potential this may have to enable land degradation or provide solutions towards LDN. The literature reveals agency shifts are taking place, where value chain actors are given increasing decision-making power in land governance. These agency shifts are manifested in two interrelated trends: First, through agricultural value chain coordination, such as contract farming, value chain actors increasingly influence land management decisions. Second, international large-scale land acquisitions and domestic larger-scale farms, both instances of intensified direct involvement of value chain with land management, are overtaking significant areas of land. These new arrangements are associated with agricultural expansion, and are additionally associated with unsustainable land management due to absent landowners, short-term interests, and high-intensity agriculture. However, we also find that value chain actors have both the tools and business cases to catalyze LDN solutions. We discuss how governments and other LDN brokers can motivate or push private actors to deploy private governance measures to avoid, reduce, and reverse land degradation. Successful implementation of LDN requires refocusing efforts to enable and, where necessary, constrain all actors with agency over land management, including value chain actors.  相似文献   

18.
Livestock grazing on natural rangeland vegetation is one of the most extensive land uses on the earth, with important implications for livelihoods, food security and the environment. Factors such as population growth and urban development, a shift from resource-based to service-based economies, and intensification in the livestock industry change the extent and practice of grazing worldwide. We investigated how and why livestock grazing on public lands changed since 1940 in the High Divide region of the Northern Rocky Mountains through a detailed analysis of United States Forest Service (USFS) rangeland management records. Based on a 90-year land use history, we process-traced the proximate causes of changes in grazing, identified the decision-makers, and statistically tested which underlying factors were associated with changes in grazing. The forage annually consumed by livestock in our study area declined by 62% since 1940, the equivalent of about 33,000 fewer cows grazing on public lands for a three-month summer period. Livestock grazing was closed on 21% of the total allotment area. The reductions in grazing were mainly caused by land management and policy factors: evaluations of range condition (27%), carrying capacity estimates (21%) and legal and administrative requirements (14%) derived from the Endangered Species Act (ESA) and National Environmental Protection Act (NEPA). The socio-economic causes of ranch economics (14%) and amenity migration (8%) were comparatively small. Overlap with wilderness and proximity to amenity towns were significant spatial predictors of reductions in grazing. The fate of publicly-owned but privately-used rangelands largely depends on institutions that are able to reconcile the competing values and demands that influence how they are managed.  相似文献   

19.
在气候变暖背景下,大兴安岭森林大火导致多年冻土退化,植被发生更新和演替,对森林生态系统服务功能造成重要影响。文中选取大兴安岭北部多年冻土区满归和阿龙山火烧区为研究对象,通过定量方法计算了林火后,固碳释氧效益损失;净化环境效益损失,包括吸收SO2和粉尘净化价值;水文效益损失,包括防洪和涵养水源效益;小气候效益损失;保护野生生物以及游憩效益损失。研究发现,满归和阿龙山火烧后,生态系统服务效益损失重大。其中,固碳释氧效益和净化环境效益损失较大,分别占总效益损失的42.34%和41.94%;水文效益和保护野生生物效益损失较小,分别为2.82%和0.80%;小气候效益和游憩效益居中,分别占8.61%和3.49%。即使针叶林生态系统恢复到阔叶林生态系统,净化环境效益损失仍然可达69.3%。由此看来,保护多年冻土区的针叶林,减少森林火灾的发生对维持多年冻土区森林生态系统的稳定性和可持续发展至关重要。  相似文献   

20.
Land managers of wetlands face various challenges emerging from climate change. Exploration of these problems is a prerequisite to developing adaptive management of vulnerable areas. Central and Eastern European countries are highly vulnerable to climate change. The Balaton Uplands National Park, an attractive tourist destination with natural values of high national and community importance, has suffered the greatest extremities in precipitation in Hungary during 2010 and 2011. After identification of stakeholder groups, private landowners and land managers as being most likely affected by climate change were interviewed in the national park. A compilation of the most important land use problems that already have influence on the management of protected wetlands was listed. Land managers connect several problems to weather extremities and long-term changes, but take practically no actions in favor of mitigation or adaptation, or strengthening resilience. As there is strong evidence that wet habitats are becoming more sensitive and vulnerable, land managers have to adapt their objectives, strategies and measures to changing climate and be involved in the process of adapting the management measures of protected areas, especially wetlands, to probable effects of climate change.  相似文献   

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