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901.
Territorial user rights for fisheries are being promoted to enhance the sustainability of small‐scale fisheries. Using Chile as a case study, we designed a market‐based program aimed at improving fishers’ livelihoods while incentivizing the establishment and enforcement of no‐take areas within areas managed with territorial user right regimes. Building on explicit enabling conditions (i.e., high levels of governance, participation, and empowerment), we used a place‐based, human‐centered approach to design a program that will have the necessary support and buy‐in from local fishers to result in landscape‐scale biodiversity benefits. Transactional infrastructure must be complex enough to capture the biodiversity benefits being created, but simple enough so that the program can be scaled up and is attractive to potential financiers. Biodiversity benefits created must be commoditized, and desired behavioral changes must be verified within a transactional context. Demand must be generated for fisher‐created biodiversity benefits in order to attract financing and to scale the market model. Important design decisions around these 3 components—supply, transactional infrastructure, and demand—must be made based on local social‐ecological conditions. Our market model, which is being piloted in Chile, is a flexible foundation on which to base scalable opportunities to operationalize a scheme that incentivizes local, verifiable biodiversity benefits via conservation behaviors by fishers that could likely result in significant marine conservation gains and novel cross‐sector alliances. Incentivar la Conservación de la Biodiversidad con Comunidades de Pesca Artesanal por medio de Derechos de Uso Territorial y la Innovación de Modelos de Negocio  相似文献   
902.
Conservation outcomes are uncertain. Agencies making decisions about what threat mitigation actions to take to save which species frequently face the dilemma of whether to invest in actions with high probability of success and guaranteed benefits or to choose projects with a greater risk of failure that might provide higher benefits if they succeed. The answer to this dilemma lies in the decision maker's aversion to risk—their unwillingness to accept uncertain outcomes. Little guidance exists on how risk preferences affect conservation investment priorities. Using a prioritization approach based on cost effectiveness, we compared 2 approaches: a conservative probability threshold approach that excludes investment in projects with a risk of management failure greater than a fixed level, and a variance‐discounting heuristic used in economics that explicitly accounts for risk tolerance and the probabilities of management success and failure. We applied both approaches to prioritizing projects for 700 of New Zealand's threatened species across 8303 management actions. Both decision makers’ risk tolerance and our choice of approach to dealing with risk preferences drove the prioritization solution (i.e., the species selected for management). Use of a probability threshold minimized uncertainty, but more expensive projects were selected than with variance discounting, which maximized expected benefits by selecting the management of species with higher extinction risk and higher conservation value. Explicitly incorporating risk preferences within the decision making process reduced the number of species expected to be safe from extinction because lower risk tolerance resulted in more species being excluded from management, but the approach allowed decision makers to choose a level of acceptable risk that fit with their ability to accommodate failure. We argue for transparency in risk tolerance and recommend that decision makers accept risk in an adaptive management framework to maximize benefits and avoid potential extinctions due to inefficient allocation of limited resources. El Efecto de la Aversión de Riesgo sobre la Priorización de Proyectos de Conservación  相似文献   
903.
Selection of areas for restoration should be based on cost‐effectiveness analysis to attain the maximum benefit with a limited budget and overcome the traditional ad hoc allocation of funds for restoration projects. Restoration projects need to be planned on the basis of ecological knowledge and economic and social constraints. We devised a novel approach for selecting cost‐effective areas for restoration on the basis of biodiversity and potential provision of 3 ecosystem services: carbon storage, water depuration, and coastal protection. We used Marxan, a spatial prioritization tool, to balance the provision of ecosystem services against the cost of restoration. We tested this approach in a mangrove ecosystem in the Caribbean. Our approach efficiently selected restoration areas that at low cost were compatible with biodiversity targets and that maximized the provision of one or more ecosystem services. Choosing areas for restoration of mangroves on the basis carbon storage potential, largely guaranteed the restoration of biodiversity and other ecosystem services. Selección de Áreas Rentables para la Restauración de Servicios Ambientales  相似文献   
904.
Established under the European Union (EU) Birds and Habitats Directives, Natura 2000 is one of the largest international networks of protected areas. With the spatial designation of sites by the EU member states almost finalized, the biggest challenge still lying ahead is the appropriate management of the sites. To evaluate the cross‐scale functioning of Natura 2000 implementation, we analyzed 242 questionnaires completed by conservation scientists involved in the implementation of Natura 2000 in 24 EU member states. Respondents identified 7 key drivers of the quality of Natura 2000 implementation. Ordered in decreasing evaluation score, these drivers included: network design, use of external resources, legal frame, scientific input, procedural frame, social input, and national or local policy. Overall, conservation scientists were moderately satisfied with the implementation of Natura 2000. Tree modeling revealed that poor application of results of environmental impact assessments (EIA) was considered a major constraint. The main strengths of the network included the substantial increase of scientific knowledge of the sites, the contribution of nongovernmental organizations, the adequate network design in terms of area and representativeness, and the adequacy of the EU legal frame. The main weaknesses of Natura 2000 were the lack of political will from local and national governments toward effective implementation; the negative attitude of local stakeholders; the lack of background knowledge of local stakeholders, which prevented well‐informed policy decisions; and the understaffing of Natura 2000 management authorities. Top suggestions to improve Natura 2000 implementation were increase public awareness, provide environmental education to local communities, involve high‐quality conservation experts, strengthen quality control of EIA studies, and establish a specific Natura 2000 fund. El Reto de Implementar la Red Europea de Áreas Protegidas Natura 2000  相似文献   
905.
Balancing ecological and social outcomes of conservation actions is recognized in global conservation policy but is challenging in practice. Compensation to land owners or users for foregone assets has been proposed by economists as an efficient way to mitigate negative social impacts of human displacement from protected areas. Joint empirical assessments of the conservation and social impacts of protected area establishment involving compensation payments are scarce. We synthesized social and biological studies related to the establishment of the Derema forest corridor in Tanzania's biodiverse East Usambara Mountains. This lengthy conservation process involved the appropriation of approximately 960 ha of native canopy agroforest and steep slopes for the corridor and monetary compensation to more than 1100 claimants in the surrounding villages. The overarching goals from the outset were to conserve ecological processes while doing no harm to the local communities. We evaluated whether these goals were achieved by analyzing 3 indicators of success: enhancement of forest connectivity, improvement of forest condition, and mitigation of negative impacts on local people's livelihoods. Indicators of forest connectivity and conditions were enhanced through reductions of forest loss and exotic species and increases in native species and canopy closure. Despite great efforts by national and international organizations, the intervention failed to mitigate livelihood losses especially among the poorest people. The Derema case illustrates the challenges of designing and implementing compensation schemes for conservation‐related displacement of people. Resultados Ecológicos y Sociales de un Área Protegida Nueva en Tanzania  相似文献   
906.
Natural resource managers are often expected to achieve both environmental protection and economic development even when there are fundamental trade‐offs between these goals. Adaptive management provides a theoretical structure for program administrators to balance social priorities in the presence of trade‐offs and to improve conservation targeting. We used the case of Mexico's federal Payments for Hydrological Services program (PSAH) to illustrate the importance of adaptive management for improving program targeting. We documented adaptive elements of PSAH and corresponding changes in program eligibility and selection criteria. To evaluate whether these changes resulted in enrollment of lands of high environmental and social priority, we compared the environmental and social characteristics of the areas enrolled in the program with the characteristics of all forested areas in Mexico, all areas eligible for the program, and all areas submitted for application to the program. The program successfully enrolled areas of both high ecological and social priority, and over time, adaptive changes in the program's criteria for eligibility and selection led to increased enrollment of land scoring high on both dimensions. Three factors facilitated adaptive management in Mexico and are likely to be generally important for conservation managers: a supportive political environment, including financial backing and encouragement to experiment from the federal government; availability of relatively good social and environmental data; and active participation in the review process by stakeholders and outside evaluators. Mejorando los Objetivos Ambiental y Social Mediante el Manejo Adaptativo en el Programa de Pagos por Servicios Hidrológicos en México  相似文献   
907.
Rising temperatures, a widespread consequence of climate change, have been implicated in enigmatic amphibian declines from habitats with little apparent human impact. The pathogenic fungus Batrachochytrium dendrobatidis (Bd), now widespread in Neotropical mountains, may act in synergy with climate change causing collapse in thermally stressed hosts. We measured the thermal tolerance of frogs along a wide elevational gradient in the Tropical Andes, where frog populations have collapsed. We used the difference between critical thermal maximum and the temperature a frog experiences in nature as a measure of tolerance to high temperatures. Temperature tolerance increased as elevation increased, suggesting that frogs at higher elevations may be less sensitive to rising temperatures. We tested the alternative pathogen optimal growth hypothesis that prevalence of the pathogen should decrease as temperatures fall outside the optimal range of pathogen growth. Our infection‐prevalence data supported the pathogen optimal growth hypothesis because we found that prevalence of Bd increased when host temperatures matched its optimal growth range. These findings suggest that rising temperatures may not be the driver of amphibian declines in the eastern slopes of the Andes. Zoonotic outbreaks of Bd are the most parsimonious hypothesis to explain the collapse of montane amphibian faunas; but our results also reveal that lowland tropical amphibians, despite being shielded from Bd by higher temperatures, are vulnerable to climate‐warming stress. Fisiología Termal, Enfermedades y Disminuciones de Anfibios en las Laderas Orientales de los Andes  相似文献   
908.
Most species face multiple anthropogenic disruptions. Few studies have quantified the cumulative influence of multiple threats on species of conservation concern, and far fewer have quantified the potential relative value of multiple conservation interventions in light of these threats. We linked spatial distribution and population viability models to explore conservation interventions under projected climate change, urbanization, and changes in fire regime on a long‐lived obligate seeding plant species sensitive to high fire frequencies, a dominant plant functional type in many fire‐prone ecosystems, including the biodiversity hotspots of Mediterranean‐type ecosystems. First, we investigated the relative risk of population decline for plant populations in landscapes with and without land protection under an existing habitat conservation plan. Second, we modeled the effectiveness of relocating both seedlings and seeds from a large patch with predicted declines in habitat area to 2 unoccupied recipient patches with increasing habitat area under 2 projected climate change scenarios. Finally, we modeled 8 fire return intervals (FRIs) approximating the outcomes of different management strategies that effectively control fire frequency. Invariably, long‐lived obligate seeding populations remained viable only when FRIs were maintained at or above a minimum level. Land conservation and seedling relocation efforts lessened the impact of climate change and land‐use change on obligate seeding populations to differing degrees depending on the climate change scenario, but neither of these efforts was as generally effective as frequent translocation of seeds. While none of the modeled strategies fully compensated for the effects of land‐use and climate change, an integrative approach managing multiple threats may diminish population declines for species in complex landscapes. Conservation plans designed to mitigate the impacts of a single threat are likely to fail if additional threats are ignored. Manejo de Incendios, Reubicación Administrada y Opciones de Conservación de Suelo para Plantas de Vida Larga con Sembrado Obligado bajo los Cambios Globales en el Clima, la Urbanización y el Régimen de Incendios  相似文献   
909.
川南地区,历史悠久,文化灿烂,风光优美,是四川的精品旅游路线之一。自贡的恐龙群窟,堪称世界奇观。盐都自贡僰海井,是中华民族智慧的结晶。万里长江第一城的宜宾,风景秀丽。珙县石碑龙,具有极高的旅游价值和重大的学术意义,僰人悬棺,是世界上最大的悬棺群。兴文石海洞乡是不可多得的喀斯特公园,其洞穴与漏斗都是世界级的,独具一格的景观配置,构成了一幅世界上极为壮观、极为独特的自然奇观。蜀南竹海更以其浩瀚的翠绿、万壑的柔情,无比的峻秀,给恐龙之乡增添了无比的美丽,无穷的魅力。  相似文献   
910.
对河流流量测量的简易方法及其方法的技术参数做具体的介绍,与其他一些传统的测量方法相比,简易测量法具有测量准确、操作简便易行、省钱、省时、省力等特点,是河流污染物总量监测里很实用的方法。  相似文献   
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