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1.
Rapidly increasing demand for food, fiber, and fuel together with new technologies and the mobility of global capital are driving revolutionary changes in land use throughout the world. Efforts to increase land productivity include conversion of millions of hectares of rangelands to crop production, including many marginal lands with low resistance and resilience to degradation. Sustaining the productivity of these lands requires careful land use planning and innovative management systems. Historically, this responsibility has been left to agronomists and others with expertise in crop production. In this article, we argue that the revolutionary land use changes necessary to support national and global food security potentially make rangeland science more relevant now than ever. Maintaining and increasing relevance will require a revolutionary change in range science from a discipline that focuses on a particular land use or land cover to one that addresses the challenge of managing all lands that, at one time, were considered to be marginal for crop production. We propose four strategies to increase the relevance of rangeland science to global land management: 1) expand our awareness and understanding of local to global economic, social, and technological trends in order to anticipate and identify drivers and patterns of conversion; 2) emphasize empirical studies and modeling that anticipate the biophysical (ecosystem services) and societal consequences of large-scale changes in land cover and use; 3) significantly increase communication and collaboration with the disciplines and sectors of society currently responsible for managing the new land uses; and 4) develop and adopt a dynamic and flexible resilience-based land classification system and data-supported conceptual models (e.g., state-and-transition models) that represent all lands, regardless of use and the consequences of land conversion to various uses instead of changes in state or condition that are focused on a single land use.  相似文献   

2.
Recent climatic trends and climate model projections indicate that climate change will modify rangeland ecosystem functions and the services and livelihoods that they provision. Recent history has demonstrated that climatic variability has a strong influence on both ecological and social components of rangeland systems and that these systems possess substantial capacity to adapt to climatic variability. Specific objectives of this synthesis are to: 1) evaluate options to mitigate greenhouse gas emissions and future climate change; 2) survey actions that individuals, enterprises, and social organizations can use to adapt to climate change; and 3) assess options for system transformation when adaptation is no longer sufficient to contend with climate change. Mitigation for carbon sequestration does not appear economically viable, given the small and highly variable carbon dioxide fluxes of rangeland ecosystems and the high transaction costs that would be incurred. In contrast, adaptation strategies are numerous and provide a means to manage risks associated with climate change. Adaptation strategies are diverse, including altered risk perception by individuals, greater flexibility of production enterprises, and modifications to social organizations that emphasize climatic variability, rather than consistency. Many adaptations represent “no regrets” actions because their implementation can be justified without emphasis on pending climate change. Adaptations specific to livestock production systems can include flexible herd management, alternative livestock breeds or species, innovative pest management, modified enterprise structures, and geographic relocation. Social-ecological systems in which adaptation is insufficient to counter the adverse consequences of climate change might undergo transformative change to produce alternative ecosystem services, production enterprises, and livelihoods. The rangeland profession is in a pivotal position to provide leadership on this global challenge because it represents the intersection of management and scientific knowledge, includes diverse stakeholders who derive their livelihoods from rangelands, and interacts with organizations responsible for rangeland stewardship.  相似文献   

3.
4.
A large number of empirical and mechanistic simulation models and decision support tools have been produced for rangelands. Collectively, these models have considerably increased our fundamental knowledge and understanding of the dynamics of ecosystem functions, processes, and structure. We explore three areas where models for rangeland management are often challenging for land managers and enterprise-level decision making: 1) coping with spatiotemporal and climatic variability in implementing scenario forecasting, risk assessments, and adaptive management; 2) addressing outputs of multiple ecosystem goods and services and determining whether they are synergistic or competitive; and 3) integrating experimental and experiential knowledge and observations into decision making. Increasing the utility of models for rangeland management remains a key frontier and a major research need for the modeling community and will be achieved less by further technical advances and model complexity and more by the use of existing topoedaphic databases, the capacity to readily incorporate new experimental and experiential knowledge, and the use of frameworks that facilitate outcome-based, adaptive decision making at the enterprise level with associated economic considerations. Opportunities exist for increasing the utility of models for decision making and adaptive rangeland management through better matching of model complexity with enterprise-level, decision-making goals. This could be accomplished by incorporating a fundamental understanding of herbivory, fire, and spatiotemporal interactions with weather patterns that affect multiple ecosystem functions. Most important, effective models would allow land managers in a changing and variable climate to 1) evaluate trade offs in producing multiple goods and services, 2) optimize the application of conservation practices spatially (comparing costs and benefits accrued across different timescales), and 3) incorporate manager capacity, including experience, skills, and labor input.  相似文献   

5.
Payments for ecosystem services and other approaches seek to expand conservation outcomes from working ranches in rangeland systems. Making these strategies attractive to ranchers and effective in achieving conservation goals requires information that is largely lacking about the human dimensions of aligning conservation, agricultural, and financial objectives on working ranches. This exploratory study addressed this knowledge gap about perceived strategies, barriers, and opportunities by interviewing a purposive sample of 23 ranchers and natural resource practitioners (e.g., government agencies, conservation nonprofits) involved in a collaborative stakeholder group in Larimer County, Colorado. Interviewees’ responses demonstrated a wide range of potential strategies for ranchers to adopt, yet their discussion of ranch-scale and regional concerns demonstrated the multiple interlinked ecological, financial, and social factors that pose challenges for mainstreaming opportunities. All interviewees expressed interest in developing a regional payment for ecosystem services program, seeing an opportunity to simultaneously support ranchers and improve conservation stewardship. However, substantial concerns were expressed regarding possible restrictions to the ranch operation, profitability, and other management and legal factors that would diminish attractiveness to ranchers. Our findings suggest that characteristics of our study system, including proximity to urban areas and the presence of a collaborative stakeholder group, contribute importantly to the opportunities and challenges perceived by interviewees. Furthermore, interviewees’ responses highlighted how factors beyond the ranch-scale can affect the viability of ranch business strategies to achieve conservation and agricultural objectives. Future research with representative populations across rangeland systems in the American West and in contexts with and without collaborative groups will build constructively upon this exploratory study.  相似文献   

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7.
In many developing countries where rangelands are a dominant land type and critically important in livelihoods of a significant portion of the population, severe rangeland degradation and/or conflicts over rangeland use can create significant social, economic, and environmental problems. In this paper, we review rangeland degradation in the developing world, its impacts and causes, discuss problems in applying rangeland science to improve rangeland conditions, discuss the role of rangeland scientists, and discuss our approach for enhancing rangeland science in international development. We suggest range scientists can provide valuable input and direction on issues of rangeland degradation (including state changes and impacts on ecosystem goods and services), provide guidance in methods and realistic opportunities for rangeland improvement to local users, government, and development organizations, and work to provide pastoralists with adaptive management in variable ecosystems. Conflict and poverty can create situations where a long-term goal of sustainable rangeland use is overwhelmed by short-term needs of safety and food security; however, providing science and training on sustainable management can make a difference where conflicts are not too severe and can help promote societal stability. Negative perceptions about aid are widespread, but the needs for improved conditions associated with multiple values of rangelands, and the needs of people utilizing these areas, are great. Conducting planning and projects with transparency and accountability will help promote more inclusive participation and successful projects. To be effective, a project needs to consider the needs of the people utilizing the project area but also provide to these communities information on values of the rangelands to other stakeholders (ecosystem services). Sustainable projects will require accountability and enhance self-reliance to allow community empowerment and adaptability to changes.  相似文献   

8.
This article examines the question of how well the rangeland management profession has served conservation of patterns and processes that support multiple ecosystem services. We examine the paradigms under which rangeland management operates and argue that our profession developed under the utilitarian paradigm with the primary goals of sustainable forage for livestock production. While optimization of multiple rangeland products and services has always been a consideration, a comprehensive set of principles have not be been developed to advance this concept. We argue that fire and grazing, often viewed as mere tools used for production goals, should rather be viewed as essential ecosystem processes. Rangeland management continues to operate under the utilitarian paradigm appropriate to societal values of the 20th century and by and large has failed to provide management guidance to reverse degradation of several highly valued ecosystem services. We support this argument with evidence that biodiversity has declined on rangelands in the past half century and that much of this decline is due to management goals that favor a narrow suite of species. The full suite of ecosystem services valued by society will only benefit by management for heterogeneity, which implies that there is no one goal for management and that landscape-level planning is crucial. Explicitly incorporating heterogeneity into state-and-transition models is an important advancement not yet achieved by our profession. We present new principles for rangeland management formed on the basis of conservation of pattern and process. While recognizing that many rangelands have significant deviations from historic plant communities and disturbance regimes, we suggest that management for conservation of pattern and process should focus on fire and grazing to the extent possible to promote a shifting mosaic across large landscapes that include patches that are highly variable in the amount of disturbance rather than the current goal of uniform moderate disturbance.  相似文献   

9.
以草地地上生物量为基础,运用经济学的市场价值法、物质量法、水量平衡法等方法对太仆寺旗和沽源县境内的农牧交错区草地的固定CO2、释放O2、土壤侵蚀控制、涵养水源、营养物质循环5项生态系统服务功能进行初步的评估。结果表明:由这5项功能构成的生态系统服务的间接价值在农区为16 668元/(hm2·a),在草原区为17 223元/(hm2·a)。尽管草原区的间接价值比农区的高3.33%,但研究所选的农牧交错区由于农业活动的干扰,并没有导致草地生态系统服务功能间接价值的显著下降。这说明维持现阶段的农业活动或退耕还草可能促进草地生态系统生态经济价值的可持续性发展;但若继续开垦和破坏草地,草地生态系统的服务功能可能会显著下降,草地所具有的生态屏障作用也会减弱甚至消失。  相似文献   

10.
Crossing disciplinary boundaries, particularly between social and ecological sciences, challenges those seeking to contribute to solving complex and multidimensional environmental problems on rangelands. In this Special Issue we present a set of 13 papers that to varying degrees attempt to integrate, or bring together, diverse approaches across disciplines to understand silvopastoral systems. The papers are about rangelands in numerous countries and regions, including Spain, Estonia, Greece, Germany, Hungary, Italy, Portugal, Romania, the United States, Latin America, and Sweden. Silvopastoral systems provide ecosystem goods and services important to communities, cultures, and society. Management deliberately exploits the diversity fostered by rangeland systems that mix woody species with a well-developed herbaceous understory, offering a greater diversity of products, species, vegetation structural characteristics, and habitat components than either grassland or forest. Biodiversity often peaks at the intermediate levels of tree and shrub cover characteristic of silvopastoral systems. We introduce the papers grouped by four overarching topics: 1) typologies and scales, 2) social-ecological interactions, 3) integrated management, and 4) multiple knowledge systems. Unfortunately, silvopastoral systems often run afoul of ongoing intensification and simplification trends in agricultural production that reduce their economic and ecological resilience. Privately owned systems, the most common in this issue, are subject to the need for owner income. Finding ways to support the benefits of these systems for the public is difficult, as management traditions must be conserved as well as the land. We hope this issue illustrates the value of multifunctional systems and offers insights into how they work.  相似文献   

11.
姜晓群  林哲艳  时钰  赵晋灵  李昂 《草业学报》2020,29(11):151-164
当初步遏制草地退化后,我国当前迫切需要对草地管理政策进行优化和调整,进而更好地通过草畜平衡和生态补贴实现生态保育和牧民利益的协调和可持续发展目标。长达90年的美国公共放牧地政策可以为我国调整和优化草地管理政策提供借鉴。美国经验表明,实现草地生态保育需要在社会共识、法律体系和行政管理等方面,牢固地树立和实现草地的多重功能和生态系统服务理念。进一步地,公有的草地产权制度是保障草地多重生态系统服务的法律前提,非牧产业发展是实现草地多重功能的经济基础,精细的行政管理是实现草地生产生态平衡的技术保障,多种利益主体参与是实现草地管理制度改革的活力来源。美国草地管理制度发展的曲折反复,也说明了生态管理政策的失效和调整,禁牧和监管强度的张弛反复,不同利益集团的矛盾诉求和博弈消长,都是草地治理中的正常情况。我国草地治理也可能经历复杂曲折的过程。在下一阶段,草地产权的优化、行政管理的精细化、牧民利益和生态保育目标的协调,是实现我国草地可持续治理的核心要务。  相似文献   

12.
The ecological impacts of rangeland invasive plants have been widely documented, but the social aspects of how managers perceive their impacts and options for control have been relatively understudied, and successful, long-term invasive plant management programs are limited. In particular, though a growing body of research has identified livestock grazing as the most practical and economical tool for controlling invasive rangeland plants, to date there has not been a systematic assessment of the challenges and opportunities producers and other land managers see as most important when considering using livestock to manage invasive plants. In-depth, semistructured interviews with California annual grass and hardwood rangeland ranchers, public agency personnel, and nongovernmental organization land managers were used to address this need. Although interviewees broadly agreed that grazing could be an effective management tool, differences emerged among the three groups in how they prioritized invasive plant control, the amount of resources devoted to control, and the grazing strategies employed. Interviewees identified key challenges that hinder broad-scale adoption of control efforts, including the potential incompatibility of invasive plant management and livestock production; a lack of secure, long-term access to land for many ranchers; incomplete or insufficient information, such as the location or extent of infestations or the economic impacts to operations of invasive plants; and the temporal and spatial variability of the ecosystem. By identifying key socioecological drivers that influence the degree to which livestock are used to manage invasive plants, this study was able to identify potential pathways to move our growing understanding of the science of targeted grazing into practice. Research, extension, and grazing programs that address these barriers should help increase the extent to which we can effectively use livestock to slow and perhaps reverse the spread of some of our most serious rangeland weeds.  相似文献   

13.
The objective of this paper is to recommend conceptual modifications for incorporation in state-and-transition models (STMs) to link this framework explicitly to the concept of ecological resilience. Ecological resilience describes the amount of change or disruption that is required to transform a system from being maintained by one set of mutually reinforcing processes and structures to a different set of processes and structures (e.g., an alternative stable state). In light of this concept, effective ecosystem management must focus on the adoption of management practices and policies that maintain or enhance ecological resilience to prevent stable states from exceeding thresholds. Resilience management does not exclusively focus on identifying thresholds per se, but rather on within-state dynamics that influence state vulnerability or proximity to thresholds. Resilience-based ecosystem management provides greater opportunities to incorporate adaptive management than does threshold-based management because thresholds emphasize limits of state resilience, rather than conditions that determine the probability that these limits will be surpassed. In an effort to further promote resilience-based management, we recommend that the STM framework explicitly describe triggers, at-risk communities, feedback mechanisms, and restoration pathways and develop process-specific indicators that enable managers to identify at-risk plant communities and potential restoration pathways. Two STMs representing different ecological conditions and geographic locations are presented to illustrate the incorporation and application of these recommendations. We anticipate that these recommendations will enable STMs to capture additional ecological information and contribute to improved ecosystem management by focusing attention on the maintenance of state resilience in addition to the anticipation of thresholds. Adoption of these recommendations may promote valuable dialogue between researchers and ecosystem managers regarding the general nature of ecosystem dynamics.  相似文献   

14.
The creation of local institutions with a mandate over land access and control is seen as a prerequisite for successful decentralisation of land tenure and effective local resource management in sub-Saharan Africa. However, with land tenure reform in South Africa currently at a state of legislative impasse, real uncertainty now exists over land rights and governance of rangeland in many communal areas. This paper draws on case study material from Eastern Cape province to illustrate how this ongoing uncertainty has resulted in the operation of a range of traditional authority and civil society institutions in different communal areas with varying degrees of legitimate authority over land administration and highly variable performance in managing rangeland resources. Collective management of rangeland resources seems most difficult in environments where land rights are contested because of the coexistence of traditional leaders and civil society institutions. On this basis an approach to tenure reform is advocated, which vests all powers over local land administration in democratically elected and accountable civil society institutions. Some successful examples of this already exist and might serve to guide policy formation, which must be flexible enough to accommodate collective management approaches that emphasise cooperation both within and between communities.  相似文献   

15.
Working ranches are often promoted as means of private rangeland conservation because they can safeguard ecosystem services, protect open space, and maintain traditional ranching culture. To understand the potential for generating broad social benefits from what have come to be called “working landscapes,” one must consider the synergies of people, environment, and institutions needed to accomplish conservation, as well as complicating factors of scale and uncertainty. Focusing on the problem as it has unfolded in the western United States, we review the state of knowledge about the extent of ranchland conversion; reasons why maintaining working ranches may benefit conservation; and the challenges and opportunities of rancher demographics, attitudes, values, and propensities for innovation. Based on this review, we explore whether the supply of traditional, full-time ranch owners is likely to be sufficient to meet conservation demand, and conclude that although demographic trends seem to suggest that it is not, there exist alternative enterprises and ownership forms that could achieve the goals of ranch conservation. We offer suggestions on how potential shortfalls might be addressed.  相似文献   

16.
中国草地资源经营的历史发展与当前任务   总被引:8,自引:3,他引:5  
许鹏 《草地学报》2005,13(Z1):1-3,9
回顾近40年中国草地资源经营发展历程,分析了存在问题及其原因,提出了当前任务:1.要明确工作总则,围绕生态与小康两大目标,思考与部署草地资源经营工作;确立草地生态置换理论与对策;组建草原生态建设与草原牧业发展综合治理工程.2.要做好退牧还草工程,主要是把握实质做出实效;做好统筹规划、加强综合治理;因地制宜,做好实施方案;提高科技含量,做好基础工作,特别是治理区水、草、林、土资源本底重估与优化配置,草牧产业发展要点,以及牧民定居点建设工作.  相似文献   

17.
In this article we test the notion that adaptation to climate change in grazed rangelands requires little more effort than current approaches to risk management because the inherent climate variability that characterizes rangelands provides a management environment that is preadapted to climate change. We also examine the alternative hypothesis that rangeland ecosystems and the people they support are highly vulnerable to climate change. Past climate is likely to become an increasingly poor predictor of the future, so there is a risk in relying on adaptation approaches developed solely in response to existing variability. We find incremental, autonomous adaptation will be sufficient to deal with most of the challenges provided by the gradual expression of climate change in the next decade or two. However, projections of greater climate change in the future means that the responses required are qualitatively as well as quantitatively different and are beyond the existing suite of adaptation strategies and coping range. The proactive adaptation responses required go well beyond incremental on-farm or local actions. New policies will be needed to deal with transformational changes associated with land tenure issues and challenges of some displacement and migration of people in vulnerable parts of rangelands. Even where appropriate adaptation actions can be framed, issues of when to act and how much to act in a proactive way remain a challenge for research, management, and policy. Whether incremental or transformational involving system changes, a diversity of adaptation options will be required in different rangeland regions to enhance social and ecological resilience.  相似文献   

18.
The emergence of markets for mitigation of climate change presents new opportunities for increasing economic and ecological returns to rangelands in developing countries. Improving rangeland management is a potentially significant source of mitigation from sequestration. It is appealing due to the likely links to sustainable agricultural development and poverty reduction. Many of the changes needed to sequester carbon are also associated with improved rangeland productivity and incomes. We provide an overview of the key issues that arise in determining the potential of carbon markets to support improved rangeland management focusing on West Africa, an area where pastoralism is a major economic activity with extensive rangelands that offer considerable potential for sequestering carbon. Estimates of the potential for increasing sequestration through improved rangeland management are summarized. Per hectare amounts are low, but aggregate potential is high. Carbon emission reductions are generated by reducing or avoiding land degradation, rehabilitating degraded lands, and increasing native carbon stocks by increasing aboveground and belowground biomass. Avoiding degradation and rehabilitating lightly degraded lands are the least costly and can generate significant carbon emission reductions. Carbon offsets from agricultural sources are currently limited under regulatory cap and trade regimes, and prices in voluntary markets are relatively low. Low returns to carbon offsets per hectare mean that significant co-benefits in the form of increased rangeland productivity and incomes would be necessary to induce participation. High transactions costs can be a problem in carbon markets and in adopting improved rangeland management practices, highlighting the need for institutions to provide effective coordination, monitoring, and enforcement. Evidence from Burkina Faso suggests the potential for existing local-level institutions to play an important role in future carbon payment programs, should they emerge.  相似文献   

19.
Local observations of ecological change are important in developing tools for rangeland management and filling in gaps where quantitative data are lacking. Traditional ecological knowledge (TEK) is a potential source of information that can complement scientific knowledge. It may also allow policy makers and scientists to suggest responses that will be locally relevant, and therefore effective on the ground. We conducted 40 surveys with the use of closed-ended questionnaires followed by open-ended qualitative questions with herders in two soum (administrative districts), located in the steppe and forest steppe of Mongolia. Respondents were asked about their observations of rangeland change and its causes in the last 20 yr. Across the study areas, a strong majority (75%) of all herders reported that rangeland condition was much worse than 20 yr ago. Herders in both soum reported increases in undesirable plant species, declines in species richness, and the disappearance or decreasing abundance of specific desirable plant species. Comparing the two soum, more herders in the forest-steppe site (90%) reported that rangeland condition was much worse than reported by herders in the steppe site (65%). In qualitative responses to open-ended questions, herders identified multiple indicators of and causes behind degradation, including very heavy grazing. In a large, sparsely populated country like Mongolia, herders' observations may serve as an early warning of rangeland change, provide insights into causes of change, and identify key uncertainties. Community-based rangeland management organizations (CBRMs) could help to translate herder observations into action by participating in formal monitoring based on herder-identified indicators and implementing changes in management in response to observed change. However, herders cannot address all issues that might be contributing to troubling ecological trends without higher-level policy coordinating rangeland monitoring and herder movements at regional and national scales.  相似文献   

20.
Monitoring rangeland ecosystem dynamics, production, and performance is valuable for researchers and land managers. However, ecosystem monitoring studies can be difficult to interpret and apply appropriately if management decisions and disturbances are inseparable from the ecosystem's climate signal. This study separates seasonal weather influences from influences caused by disturbances and management decisions, making interannual time-series analysis more consistent and interpretable. We compared the actual ecosystem performance (AEP) of five rangeland vegetation types in the Owyhee Uplands for 9 yr to their expected ecosystem performance (EEP). Integrated growing season Normalized Difference Vegetation Index data for each of the nine growing seasons served as a proxy for annual AEP. Regression-tree models used long-term site potential, seasonal weather, and land cover data sets to generate annual EEP, an estimate of ecosystem performance incorporating annual weather variations. The difference between AEP and EEP provided a performance measure for each pixel in the study area. Ecosystem performance anomalies occurred when the ecosystem performed significantly better or worse than the model predicted. About 14% of the Owyhee Uplands showed a trend of significant underperformance or overperformance (P < 0.10). Land managers can use results from weather-based rangeland ecosystem performance models to help support adaptive management strategies.  相似文献   

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