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1.
A.R.E. SINCLAIR†‡‡ SIMON A.R. MDUMA† J. GRANT C. HOPCRAFT‡ JOHN M. FRYXELL§ RAY HILBORN†† SIMON THIRGOOD‡ 《Conservation biology》2007,21(3):580-590
Abstract: Data from long-term ecological studies further understanding of ecosystem dynamics and can guide evidence-based management. In a quasi-natural experiment we examined long-term monitoring data on different components of the Serengeti-Mara Ecosystem to trace the effects of disturbances and thus to elucidate cause-and-effect connections between them. The long-term data illustrated the role of food limitation in population regulation in mammals, particularly in migratory wildebeest and nonmigratory buffalo. Predation limited populations of smaller resident ungulates and small carnivores. Abiotic events, such as droughts and floods, created disturbances that affected survivorship of ungulates and birds. Such disturbances showed feedbacks between biotic and abiotic realms. Interactions between elephants and their food allowed savanna and grassland communities to co-occur. With increased woodland vegetation, predators' capture of prey increased. Anthropogenic disturbances had direct (hunting) and indirect (transfer of disease to wildlife) effects. Slow and rapid changes and multiple ecosystem states became apparent only over several decades and involved events at different spatial scales. Conservation efforts should accommodate both infrequent and unpredictable events and long-term trends. Management should plan on the time scale of those events and should not aim to maintain the status quo. Systems can be self-regulating through food availability and predator-prey interactions; thus, culling may not be required. Ecosystems can occur in multiple states; thus, there may be no a priori need to maintain one natural state. Finally, conservation efforts outside protected areas must distinguish between natural change and direct human-induced change. Protected areas can act as ecological baselines in which human-induced change is kept to a minimum 相似文献
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Status of Species Conservation Banking in the United States 总被引:1,自引:0,他引:1
Abstract: Receiving financial gains for protecting habitat may be necessary to proactively protect endangered species in the United States. Species conservation banking, the creation and trading of "credits" that represent biodiversity values on private land, is nearly a decade old. We detail the biological, financial, and political experience of conservation banking in the United States. We contacted agencies, nongovernmental organizations, and bank owners and compiled comprehensive accounts of the experiences of current banks. There are 76 properties identified as conservation banks in the United States, but only 35 of these are established under a conservation banking agreement approved by the U.S. Fish and Wildlife Service (USFWS). The 35 official conservation banks cumulatively cover 15,987 ha and shelter a range of biodiversity, including more than 22 species listed under the U.S. Endangered Species Act. Financial motives drove the establishment of 91% of conservation banks, and the majority of for-profit banks are breaking even or making money. With credit prices ranging from $3,000 to $125,000/0.41 ha (1 acre), banking agreements offer financial incentives that compete with development and provide a business-based argument for conserving habitat. Although the bureaucracy of establishing an agreement with the USFWS was burdensome, 63% of bank owners reported they would set up another agreement given the appropriate opportunity. Increasing information sharing, decreasing the time to establish agreements (currently averaging 2.18 years), and reducing bureaucratic challenges can further increase the amount of private property voluntarily committed to banking. Although many ecological uncertainties remain, conservation banking offers at least a partial solution to the conservation versus development conflict over biodiversity. 相似文献
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Payments for Ecosystem Services as a Framework for Community-Based Conservation in Northern Tanzania 总被引:1,自引:0,他引:1
FRED NELSON CHARLES FOLEY† LARA S. FOLEY† ABRAHAM LEPOSO‡ EDWARD LOURE‡ DAVID PETERSON§ MIKE PETERSON§ THAD PETERSON§ HASSAN SACHEDINA ANDREW WILLIAMS†† 《Conservation biology》2010,24(1):78-85
Abstract: Payments for ecosystem services (PES) are an increasingly promoted approach to conservation. These approaches seek to develop financial mechanisms that create economic incentives for the maintenance of ecosystems and associated biodiversity by rewarding those who are responsible for provision of ecological services. There are, however, few cases in which such schemes have been used as a strategy for conserving wildlife in developing countries and very few operational examples of such schemes of any sort in sub-Saharan Africa. In savannah ecosystems, large mammal populations generally depend on seasonal use of extensive areas and are widely declining as a result of habitat loss, overexploitation, and policies that limit local benefits from wildlife. Community-based conservation strategies seek to create local incentives for conserving wildlife, but often have limited impact as a result of persistent institutional barriers that limit local rights and economic benefits. In northern Tanzania, a consortium of tourism operators is attempting to address these challenges through an agreement with a village that possesses part of a key wildlife dispersal area outside Tarangire National Park. The operators pay the community to enforce voluntary restrictions on agricultural cultivation and permanent settlement in a defined area of land. The initiative represents a potentially cost-effective framework for community-based conservation in an ecologically important area and is helping to reconcile historically conflicting local and national interests relative to land tenure, pastoralist livelihoods, and conservation. Wider adaptation of payments for ecosystem services approaches to settings where sustaining wildlife populations depends on local stewardship may help address current challenges facing conservation outside state-protected areas in savannah ecosystems in sub-Saharan Africa and other parts of the world. 相似文献
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MARKUS J. PETERSON‡ DAMON M. HALL REA M. FELDPAUSCH-PARKER TARLA RAI PETERSON† 《Conservation biology》2010,24(1):113-119
Abstract: Conservationists commonly have framed ecological concerns in economic terms to garner political support for conservation and to increase public interest in preserving global biodiversity. Beginning in the early 1980s, conservation biologists adapted neoliberal economics to reframe ecosystem functions and related biodiversity as ecosystem services to humanity. Despite the economic success of programs such as the Catskill/Delaware watershed management plan in the United States and the creation of global carbon exchanges, today's marketplace often fails to adequately protect biodiversity. We used a Marxist critique to explain one reason for this failure and to suggest a possible, if partial, response. Reframing ecosystem functions as economic services does not address the political problem of commodification. Just as it obscures the labor of human workers, commodification obscures the importance of the biota (ecosystem workers) and related abiotic factors that contribute to ecosystem functions. This erasure of work done by ecosystems impedes public understanding of biodiversity. Odum and Odum's radical suggestion to use the language of ecosystems (i.e., emergy or energy memory) to describe economies, rather than using the language of economics (i.e., services) to describe ecosystems, reverses this erasure of the ecosystem worker. Considering the current dominance of economic forces, however, implementing such solutions would require social changes similar in magnitude to those that occurred during the 1960s. Niklas Luhmann argues that such substantive, yet rapid, social change requires synergy among multiple societal function systems (i.e., economy, education, law, politics, religion, science), rather than reliance on a single social sphere, such as the economy. Explicitly presenting ecosystem services as discreet and incomplete aspects of ecosystem functions not only allows potential economic and environmental benefits associated with ecosystem services, but also enables the social and political changes required to ensure valuation of ecosystem functions and related biodiversity in ways beyond their measurement on an economic scale. 相似文献
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MATTHEW A. BOWKER MARK E. MILLER JAYNE BELNAP THOMAS D. SISK NANCY C. JOHNSON 《Conservation biology》2008,22(6):1533-1543
Abstract: Conservation prioritization usually focuses on conservation of rare species or biodiversity, rather than ecological processes. This is partially due to a lack of informative indicators of ecosystem function. Biological soil crusts (BSCs) trap and retain soil and water resources in arid ecosystems and function as major carbon and nitrogen fixers; thus, they may be informative indicators of ecosystem function. We created spatial models of multiple indicators of the diversity and function of BSCs (species richness, evenness, functional diversity, functional redundancy, number of rare species, number of habitat specialists, nitrogen and carbon fixation indices, soil stabilization, and surface roughening) for the 800,000‐ha Grand Staircase‐Escalante National Monument (Utah, U.S.A.). We then combined the indicators into a single BSC function map and a single BSC biodiversity map (2 alternative types of conservation value) with an unweighted averaging procedure and a weighted procedure derived from validations performance. We also modeled potential degradation with data from a rangeland assessment survey. To determine which areas on the landscape were the highest conservation priorities, we overlaid the function‐ and diversity‐based conservation‐value layers on the potential degradation layer. Different methods for ascribing conservation‐value and conservation‐priority layers all yielded strikingly similar results (r= 0.89–0.99), which suggests that in this case biodiversity and function can be conserved simultaneously. We believe BSCs can be used as indicators of ecosystem function in concert with other indicators (such as plant‐community properties) and that such information can be used to prioritize conservation effort in drylands. 相似文献
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ANDREW T. KNIGHT†† RICHARD M. COWLING MATHIEU ROUGET† REW BALMFORD‡ AMANDA T. LOMBARD§ BRUCE M. CAMPBELL 《Conservation biology》2008,22(3):610-617
Abstract: Conservation assessment is a rapidly evolving discipline whose stated goal is the design of networks of protected areas that represent and ensure the persistence of nature (i.e., species, habitats, and environmental processes) by separating priority areas from the activities that degrade or destroy them. Nevertheless, despite a burgeoning scientific literature that ever refines these techniques for allocating conservation resources, it is widely believed that conservation assessments are rarely translated into actions that actually conserve nature. We reviewed the conservation assessment literature in peer‐reviewed journals and conducted survey questionnaires of the authors of these studies. Two‐thirds of conservation assessments published in the peer‐reviewed scientific literature do not deliver conservation action, primarily because most researchers never plan for implementation. This research–implementation gap between conservation science and real‐world action is a genuine phenomenon and is a specific example of the “knowing–doing gap” that is widely recognized in management science. Given the woefully inadequate resources allocated for conservation, our findings raise questions over the utility of conservation assessment science, as currently practiced, to provide useful, pragmatic solutions to conservation planning problems. A reevaluation of the conceptual and operational basis of conservation planning research is urgently required. We recommend the following actions for beginning a process for bridging the research–implementation gap in conservation planning: (1) acknowledge the research–implementation gap is real, (2) source research questions from practitioners, (3) situate research within a broader conservation planning model, (4) expand the social dimension of conservation assessments, (5) support conservation plans with transdisciplinary social learning institutions, (6) reward academics for societal engagement and implementation, and (7) train students in skills for “doing” conservation. 相似文献
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Abstract: Suburban, exurban, and rural development in the United States consumes nearly 1 million hectares of land per year and is a leading threat to biodiversity. In response to this threat, conservation development has been advanced as a way to combine land development and land conservation while providing functional protection for natural resources. Yet, although conservation development techniques have been in use for decades, there have been few critical evaluations of their conservation effectiveness. We addressed this deficiency by assessing the conservation outcomes of one type of conservation development project: conservation and limited development projects (CLDPs). Conducted by land trusts, landowners, and developers, CLDPs use revenue from limited development to finance the protection of land and natural resources. We compared a sample of 10 CLDPs from the eastern United States with their respective baseline scenarios (conventional development) and with a sample of conservation subdivisions—a different conservation development technique characterized by higher-density development. To measure conservation success, we created an evaluation method containing eight indicators that quantify project impacts to terrestrial and aquatic ecosystems at the site and in the surrounding landscape. The CLDPs protected and managed threatened natural resources including rare species and ecological communities. In terms of conservation benefits, the CLDPs significantly outperformed their respective baseline scenarios and the conservation subdivisions. These results imply that CLDPs can offer a low-impact alternative to conventional development and a low-cost method for protecting land when conventional conservation techniques are too expensive. In addition, our evaluation method demonstrates how planners and developers can incorporate appropriate ecological considerations when designing, reviewing, and evaluating conservation development projects. 相似文献
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Abstract: Conservation development projects combine real‐estate development with conservation of land and other natural resources. Thousands of such projects have been conducted in the United States and other countries through the involvement of private developers, landowners, land trusts, and government agencies. Previous research has demonstrated the potential value of conservation development for conserving species, ecological functions, and other resource values on private lands, especially when traditional sources of conservation funding are not available. Nevertheless, the aggregate extent and effects of conservation development were previously unknown. To address this gap, we estimated the extent and trends of conservation development in the United States and characterized its key attributes to understand its aggregate contribution to land‐conservation and growth‐management objectives. We interviewed representatives from land trusts, planning agencies, and development companies, searched the Internet for conservation development projects and programs, and compiled existing databases of conservation development projects. We collected data on 3884 projects encompassing 1.38 million ha. About 43% of the projects targeted the conservation of specific plant or animal species or ecological communities of conservation concern; 84% targeted the protection of native ecosystems representative of the project area; and 42% provided buffers to existing protected areas. The percentage of protected land in conservation development projects ranged from <40% to >99%, and the effects of these projects on natural resources differed widely. We estimate that conservation development projects have protected roughly 4 million ha of land in the United States and account for about 25% of private‐land conservation activity nationwide. 相似文献
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Assessing Suitability for Conservation Action: Prioritizing Interpond Linkages for the California Tiger Salamander 总被引:3,自引:0,他引:3
CHRISTOPHER R. PYKE† 《Conservation biology》2005,19(2):492-503
Abstract: Conservation organizations and public agencies are interested in identifying and prioritizing areas for conservation action, often acquisition or easements. Typically, this requires the use of uncertain data and vaguely defined decision criteria. I developed a decision support system to address these uncertainty issues and assist in evaluating conservation opportunities for the endangered California tiger salamander ( Ambystoma californiense ) in Santa Barbara, California. Functionally defined planning units were used to aggregate data on land suitability, land cover change, salamander presence, and movement risk along potential linkages between breeding ponds. I used a fuzzy-logic-based inference engine to evaluate the planning units and rank the relative suitability of interpond linkages for conservation action. The sensitivity of the rankings was considered with respect to uncertainty in salamander occurrence data and the relationship between land-cover-change threats and site suitability. All linkages were substantially degraded, but five areas were consistently identified with high relative suitability for conservation action despite differences in assumptions and uncertainty in biological data. The combination of functionally defined planning units and a fuzzy-logic-based decision support system provides a general framework for considering the suitability of sites for conservation action. 相似文献
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Abstract: Strict protectionism, resource extraction, protected-area community outreach, ecotourism, an integrated conservation and development program, comanagement schemes, and citizen-science initiatives are all being used to help conserve the remote Katavi-Rukwa ecosystem in western Tanzania. Biological and social research show that protectionism is successful in the conservation of large mammals but fails to capture diverse species communities; extractivism is appropriate for some resources but not for others; protected-area outreach can be effective for some communities; and devolved control over wildlife, in conjunction with ecotourism and citizen science, has considerable potential in the area. The long-term nature of the research provides the necessary time frame to evaluate outcomes of different conservation strategies, uncovers dynamics within communities that affect attitudes and responses to conservation initiatives, provides impartial recommendations because changing research personnel offers different viewpoints, and, probably most importantly, enhances trust among stakeholders. Currently, there are limited institutional mechanisms for ensuring the input of biological and social science in shaping conservation practice in Tanzania, and long-term research can help informally bridge the gap 相似文献
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Assessing Conservation Management's Evidence Base: a Survey of Management-Plan Compilers in the United Kingdom and Australia 总被引:2,自引:0,他引:2
Abstract: Conservation management is becoming increasingly resource intensive as threats to biodiversity grow through habitat destruction, habitat disturbance, and overexploitation. To achieve successful conservation and sustainable use of natural resources, we need to scientifically evaluate the effectiveness of conservation interventions and provide an efficient framework through which scientific evidence can be used to support decision making in policy and practice. We conducted the first formal assessment of the extent to which scientific evidence is used in conservation management through a questionnaire survey and follow-up interviews of compilers of protected-area management plans from major conservation organizations within the United Kingdom and Australia. Our survey results show that scientific information is not being used systematically to support decision making largely because it is not easily accessible to decision makers. This, in combination with limited monitoring and evaluation of effectiveness of management interventions, results in the majority of decisions being based on experience rather than on evidence. To address this problem we propose using an evidence-based framework adapted from that used in the health services and explain how we are currently putting an equivalent framework into practice by establishing review and dissemination units to serve the conservation sector. 相似文献
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The Ecological Future of the North American Bison: Conceiving Long-Term, Large-Scale Conservation of Wildlife 总被引:2,自引:0,他引:2
ERIC W. SANDERSON KENT H. REDFORD BILL WEBER KEITH AUNE DICK BALDES JOEL BERGER † DAVE CARTER CHARLES CURTIN JAMES DERR STEVE DOBROTT EVA FEARN CRAIG FLEENER STEVE FORREST CRAIG GERLACH C. CORMACK GATES JOHN E. GROSS PETER GOGAN SHAUN GRASSEL JODI A. HILTY MARV JENSEN KYRAN KUNKEL DUANE LAMMERS RURIK LIST KAREN MINKOWSKI TOM OLSON CHRIS PAGUE PAUL B. ROBERTSON BOB STEPHENSON 《Conservation biology》2008,22(2):252-266
Abstract: Many wide-ranging mammal species have experienced significant declines over the last 200 years; restoring these species will require long-term, large-scale recovery efforts. We highlight 5 attributes of a recent range-wide vision-setting exercise for ecological recovery of the North American bison ( Bison bison ) that are broadly applicable to other species and restoration targets. The result of the exercise, the Vermejo Statement on bison restoration, is explicitly (1) large scale, (2) long term, (3) inclusive, (4) fulfilling of different values, and (5) ambitious. It reads, in part, Over the next century, the ecological recovery of the North American bison will occur when multiple large herds move freely across extensive landscapes within all major habitats of their historic range, interacting in ecologically significant ways with the fullest possible set of other native species, and inspiring, sustaining and connecting human cultures. We refined the vision into a scorecard that illustrates how individual bison herds can contribute to the vision. We also developed a set of maps and analyzed the current and potential future distributions of bison on the basis of expert assessment. Although more than 500,000 bison exist in North America today, we estimated they occupy <1% of their historical range and in no place express the full range of ecological and social values of previous times. By formulating an inclusive, affirmative, and specific vision through consultation with a wide range of stakeholders, we hope to provide a foundation for conservation of bison, and other wide-ranging species, over the next 100 years. 相似文献
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ELISE F. GRANEK DANIEL R. BRUMBAUGH† SCOTT A. HEPPELL‡ SELINA S. HEPPELL‡ DAVID SECORD§ 《Conservation biology》2005,19(4):1008-1018
Abstract: In the first comprehensive reviews since 1969, two high-level reports on the status of U.S. marine ecosystems and resources have been released: that of the nongovernmental Pew Oceans Commission in 2003 and that of the congressionally mandated U.S. Commission on Ocean Policy in 2004 . Although the two commissions differed in the breadth and depth of their mandates, their findings on the state of our oceans and need for new management approaches are similar, and their major recommendations for science, governance, management and conservation, and education echo and reinforce each other. The history behind the two commissions and the structure and objectives of each remind us of the crucial roles conservation practitioners and scientists must play in the implementation of report recommendations. The reports suggest priorities for conservation practitioners to improve science, management, conservation, governance, and education to better manage and protect ocean resources and ecosystems. To redirect activities affecting the state of global marine resources, integrated research; education and outreach by terrestrial, aquatic, and marine conservation practitioners; and a clear definition of their roles in the implementation of recommendations is essential. Marine ecosystems provide a test case of society's ability to manage complexity in human and natural systems in an integrated manner, with extensive opportunities for participation by conservation practitioners from all disciplines. 相似文献
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Elemental Conservation Units: Communicating Extinction Risk without Dictating Targets for Protection
Abstract: Conservation biologists mostly agree on the need to identify and protect biodiversity below the species level but have not yet resolved the best approach. We addressed 2 issues relevant to this debate. First, we distinguished between the abstract goal of preserving the maximum amount of unique biodiversity and the pragmatic goal of minimizing the loss of ecological goods and services given that further loss of biodiversity seems inevitable. Second, we distinguished between the scientific task of assessing extinction risk and the normative task of choosing targets for protection. We propose that scientific advice on extinction risk be given at the smallest meaningful scale: the elemental conservation unit (ECU). An ECU is a demographically isolated population whose probability of extinction over the time scale of interest (say 100 years) is not substantially affected by natural immigration from other populations. Within this time frame, the loss of an ECU would be irreversible without human intervention. Society's decision to protect an ECU ought to reflect human values that have social, economic, and political dimensions. Scientists can best inform this decision by providing advice about the probability that an ECU will be lost and the ecological and evolutionary consequences of that loss in a form that can be integrated into landscape planning. The ECU approach provides maximum flexibility to decision makers and ensures that the scientific task of assessing extinction risk informs, but remains distinct from, the normative social challenge of setting conservation targets. 相似文献
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Abstract: To supply ecosystem services, private landholders incur costs. Knowledge of these costs is critical for the design of conservation-payment programs. Estimating these costs accurately is difficult because the minimum acceptable payment to a potential supplier is private information. We describe how an auction of payment contracts can be designed to elicit this information during the design phase of a conservation-payment program. With an estimate of the ecosystem-service supply curve from a pilot auction, conservation planners can explore the financial, ecological, and socioeconomic consequences of alternative scaled-up programs. We demonstrate the potential of our approach in Indonesia, where soil erosion on coffee farms generates downstream ecological and economic costs. Bid data from a small-scale, uniform-price auction for soil-conservation contracts allowed estimates of the costs of a scaled-up program, the gain from integrating biophysical and economic data to target contracts, and the trade-offs between poverty alleviation and supply of ecosystem services. Our study illustrates an auction-based approach to revealing private information about the costs of supplying ecosystem services. Such information can improve the design of programs devised to protect and enhance ecosystem services. 相似文献
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Abstract: Successful conservation efforts require understanding human behaviors that directly affect biodiversity. Choice of household location represents an observable behavior that has direct effects on biodiversity conservation, but no one has examined the sociocultural predictors of this choice relative to its environmental impacts. We conducted a case study of the Teton Valley of Idaho and Wyoming (U.S.A.) that (1) explored relationships between sociodemographic variables, environmental attitudes, and the environmental impact of household location choices, (2) assessed the potential for small household sizes in natural areas to multiply the environmental impacts of household location decisions, and (3) evaluated how length of residency predicted the environmental attitudes of people living in natural areas. We collected sociodemographic data, spatial coordinates, and land‐cover information in a survey of 416 households drawn from a random sample of Teton Valley residents (95% compliance rate). Immigrants (respondents not born in the study area) with the lowest education levels and least environmentally oriented attitudes lived in previously established residential areas in disproportionately high numbers, and older and more educated immigrants with the most environmentally oriented attitudes lived in natural areas in disproportionately high numbers. Income was not a significant predictor of household location decisions. Those living in natural areas had more environmental impact per person because of the location and because small households (<3 people/household) were 4 times as likely in natural areas as large households. Longer residency in natural areas predicted less environmentally oriented attitudes, suggesting that living in natural areas does not foster more concern for nature. Because populaces are rapidly aging, growing more educated, and potentially growing more environmentally oriented, these patterns are troubling for biodiversity conservation. Our results demonstrate a need for environmentalists to make household location decisions that reflect their environmental attitudes and future research to address how interactions between education level, environmental attitudes, population aging, and household location choices influence biodiversity conservation. 相似文献
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DANIEL C. NEPSTAD†‡ CLAUDIA M. STICKLER†§ ORIANA T. ALMEIDA† 《Conservation biology》2006,20(6):1595-1603
Abstract: Amazon beef and soybean industries, the primary drivers of Amazon deforestation, are increasingly responsive to economic signals emanating from around the world, such as those associated with bovine spongiform encephalopathy (BSE, "mad cow disease") outbreaks and China's economic growth. The expanding role of these economic "teleconnections" (coupled phenomena that take place in distant places on the planet) led to a 3-year period (2002–2004) of historically high deforestation rates. But it also increases the potential for large-scale conservation in the region as markets and finance institutions demand better environmental and social performance of beef and soy producers. Cattle ranchers and soy farmers who have generally opposed ambitious government regulations that require forest reserves on private property are realizing that good land stewardship—including compliance with legislation—may increase their access to expanding domestic and international markets and to credit and lower the risk of "losing" their land to agrarian reform. The realization of this potential depends on the successful negotiation of social and environmental performance criteria and an associated system of certification that are acceptable to both the industries and civil society. The foot-and-mouth eradication system, in which geographic zones win permission to export beef, may provide an important model for the design of a low-cost, peer-enforced, socioenvironmental certification system that becomes the mechanism by which beef and soy industries gain access to markets outside the Amazon. 相似文献
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Abstract: Protected areas must be close, or connected, enough to allow for the preservation of large‐scale ecological and evolutionary processes, such as gene flow, migration, and range shifts in response to climate change. Nevertheless, it is unknown whether the network of protected areas in the United States is connected in a way that will preserve biodiversity over large temporal and spatial scales. It is also unclear whether protected‐area networks that function for larger species will function for smaller species. We assessed the connectivity of protected areas in the three largest biomes in the United States. With methods from graph theory—a branch of mathematics that deals with connectivity and flow—we identified and measured networks of protected areas for three different groups of mammals. We also examined the value of using umbrella species (typically large‐bodied, far‐ranging mammals) in designing large‐scale networks of protected areas. Although the total amount of protected land varied greatly among biomes in the United States, overall connectivity did not. In general, protected‐area networks were well connected for large mammals but not for smaller mammals. Additionally, it was not possible to predict connectivity for small mammals on the basis of connectivity for large mammals, which suggests the umbrella species approach may not be an appropriate design strategy for conservation networks intended to protect many species. Our findings indicate different strategies should be used to increase the likelihood of persistence for different groups of species. Strategic linkages of existing lands should be a conservation priority for smaller mammals, whereas conservation of larger mammals would benefit most from the protection of more land. 相似文献