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1.
Federal land managers are faced with the task of balancing multiple uses and goals when making decisions about land use and the activities that occur on public lands. Though climate change is now well recognized by federal agencies and their local land and resource managers, it is not yet clear how issues related to climate change will be incorporated into on-the-ground decision making within the framework of multiple use objectives. We conducted a case study of a federal land management agency field office, the San Juan Public Lands Center in Durango, CO, U.S.A., to understand from their perspective how decisions are currently made, and how climate change and carbon management are being factored into decision making. We evaluated three major management sectors in which climate change or carbon management may intersect other use goals: forests, biofuels, and grazing. While land managers are aware of climate change and eager to understand more about how it might affect land resources, the incorporation of climate change considerations into everyday decision making is currently quite limited. Climate change is therefore on the radar screen, but remains a lower priority than other issues. To assist the office in making decisions that are based on sound scientific information, further research is needed into how management activities influence carbon storage and resilience of the landscape under climate change.  相似文献   

2.
Climate change affects public land ecosystems and services throughout the American West and these effects are projected to intensify. Even if greenhouse gas emissions are reduced, adaptation strategies for public lands are needed to reduce anthropogenic stressors of terrestrial and aquatic ecosystems and to help native species and ecosystems survive in an altered environment. Historical and contemporary livestock production—the most widespread and long-running commercial use of public lands—can alter vegetation, soils, hydrology, and wildlife species composition and abundances in ways that exacerbate the effects of climate change on these resources. Excess abundance of native ungulates (e.g., deer or elk) and feral horses and burros add to these impacts. Although many of these consequences have been studied for decades, the ongoing and impending effects of ungulates in a changing climate require new management strategies for limiting their threats to the long-term supply of ecosystem services on public lands. Removing or reducing livestock across large areas of public land would alleviate a widely recognized and long-term stressor and make these lands less susceptible to the effects of climate change. Where livestock use continues, or where significant densities of wild or feral ungulates occur, management should carefully document the ecological, social, and economic consequences (both costs and benefits) to better ensure management that minimizes ungulate impacts to plant and animal communities, soils, and water resources. Reestablishing apex predators in large, contiguous areas of public land may help mitigate any adverse ecological effects of wild ungulates.  相似文献   

3.
2 was obtained from the output of the Canadian Climate Center General Circulation Model. To illustrate the effect of projected climate change on lake DO characteristics, we present herein DO information simulated, respectively, with inputs of past climate conditions (1961–1979) and with a projected 2 × CO2 climate scenario, as well as differences of those values. Specific parameters obtained were minimum under-ice and lake bottom DO concentration in winter, duration of under-ice anoxic conditions (<0.1 mg/liter) and low DO conditions (<3 mg/liter), and percentage of anoxic and low DO lake volumes during the ice cover period. Under current climate conditions winterkill occurs typically in shallow eutrophic lakes of the northern contiguous United States. Climate warming is projected to eliminate winterkill in these lakes. This would be a positive effect of climate warming. Fish species under ice may still experience periods of stress and zero growth due to low DO (<3 mg/liter) conditions under projected climate warming.  相似文献   

4.
5.
/ Implemented in the context of a long history ofintense public debate, forestry practices applied on private forest land areregulated in some form by 38 states. State regulatory activities can involvemany agencies implementing numerous regulatory laws, a single forestry agencyadministering a comprehensive regulatory program, or a combination of thetwo. Regulatory programs are designed to protect resources such as soils,water, wildlife, and scenic beauty. Program administration often involvesrule promulgation, harvest plan reviews, coordination of interagency reviews,and pre- and postharvest on-site inspections. Forest practice rules usuallyfocus on reforestation, forest roads, harvest procedures, and wildlifehabitat protection. Emerging regulatory trends include growth of multiagencyregulatory authority and associated jurisdictional conflicts, increasedtendencies to narrowly specify standards in statutes and rules, emergence ofcontingent regulations, growing sensitivity to processes enabling theadoption of new forest practice technologies and an ability to addresscumulative effects, interest in collaborative rule-making stemming fromheightened concern over legalization of administration processes, and growingconcern over the constitutional foundations for regulatory programs and thegovernment and private sector cost of implementing such programs.KEY WORDS: Ecosystem management; Forestry practices; Private landowners;Regulatory programs; State government  相似文献   

6.
In a previous article, Beschta et al. (Environ Manag 51(2):474–491, 2013) argue that grazing by large ungulates (both native and domestic) should be eliminated or greatly reduced on western public lands to reduce potential climate change impacts. The authors did not present a balanced synthesis of the scientific literature, and their publication is more of an opinion article. Their conclusions do not reflect the complexities associated with herbivore grazing. Because grazing is a complex ecological process, synthesis of the scientific literature can be a challenge. Legacy effects of uncontrolled grazing during the homestead era further complicate analysis of current grazing impacts. Interactions of climate change and grazing will depend on the specific situation. For example, increasing atmospheric CO2 and temperatures may increase accumulation of fine fuels (primarily grasses) and thus increase wildfire risk. Prescribed grazing by livestock is one of the few management tools available for reducing fine fuel accumulation. While there are certainly points on the landscape where herbivore impacts can be identified, there are also vast grazed areas where impacts are minimal. Broad scale reduction of domestic and wild herbivores to help native plant communities cope with climate change will be unnecessary because over the past 20–50 years land managers have actively sought to bring populations of native and domestic herbivores in balance with the potential of vegetation and soils. To cope with a changing climate, land managers will need access to all available vegetation management tools, including grazing.  相似文献   

7.
The current and projected future physical impacts of climate change are most extreme in the northern latitudes. The indigenous peoples in the North American arctic and sub-arctic rely on the availability of natural resources in mixed subsistence economies for nutritional and cultural survival and thus experience disproportionate burdens with respect to our changing climate. Arctic climate impacts exemplify how global phenomena and activities can significantly affect people locally in remote regions. These impacts are largely consistent throughout the region, irrespective of national boarders; however, indigenous peoples in Canada are better positioned than those in the United States to shape policy in a way that would ensure their adaptation to climate change. Political and industrial activity on national and global scales can have significant environmental, social and cultural repercussions on the local scale in remote areas. Remedies for environmental injustice will thus require strong cross-scale political and institutional linkages.  相似文献   

8.
/ Ecological restoration is increasingly invoked as a tool for the maintenance and regeneration of biodiversity. Yet the conceptual foundations and assumptions underlying many restoration management activities are frequently unclear or unstated. Unforeseen, undesirable consequences of restoration activities may emerge as a result. A general conceptual framework for restoration is needed to better accommodate dynamic habitat systems and evolving biota in restoration strategies. A preliminary framework for stream habitat restoration emphasizing stream habitat-biota development is proposed. As developing systems, streams and stream biota exhibit temporal behaviors that change with stream environments. Underlying the dynamic development of streams is potential capacity. Streams express this capacity as an array of habitats over time and across the landscape. Human land uses in the western United States have rapidly altered aquatic habitats and the processes that shape habitat. As a result, the diversity of native fishes and their habitats has been suppressed. Restoration is fundamentally about allowing stream systems to reexpress their capacities. Several steps are provided to guide stream restoration activities. Key tasks include: identification of the historic patterns of habitat development; identification of developmental constraints; relief of those constraints; classification of sensitive, critical, or refuge habitats; protection of the developmental diversity that remains; and monitoring of biotic responses to habitat development. KEY WORDS: Stream habitat; Stream biota; System capacity; System development; Restoration; Classification  相似文献   

9.
In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.  相似文献   

10.
For many citizens and policymakers, the empirical relationship between economic growth and biodiversity conservation has not been sufficiently established for purposes of identifying the types of economic policies amenable to biodiversity conservation. Some think economic growth conflicts with biodiversity conservation; others think economic growth conduces biodiversity conservation. With panel data from 1997‐2011, encompassing US continental states, we developed a series of statistical models to investigate the relationships among species endangerment, human population, and economic growth as indicated by GDP and per capita GDP. Species endangerment is highly correlated with population and GDP, and per capita GDP is a significant regressor of species endangerment. Across US continental states, competitive exclusion of non‐human species occurs via human economic growth and population growth.  相似文献   

11.
Recent wetland area trends were estimated from the National Resources Inventory (NRI) for nonfederal rural lands for the period 1982–1987. NRI-based estimates of wetland area for states comprising the conterminous United States were highly correlated with estimates made by the US Fish and Wildlife Service and with estimates of coastal salt marsh wetlands made by the National Oceanic and Atmospheric Administration. Net wetland area declined by 1.1% (≈363,200 ha) during the five-year study period. Conversion to open water, primarily caused by natural flooding in western inland basins, was responsible for altering extensive wetland areas (≈171,400 ha). Of the human-induced wetland conversions, urban and built-up land was responsible for 48% of the wetland loss, while agricultural development was indicated in 37% of the converted wetland area. A decrease in rural land, and increases in both population, and urban and built-up land were associated with wetland loss among states. Potential reasons for wetland loss were different in 20 coastal states than in 28 inland states. Proportionately, wetland loss due to development was three times greater in coastal states than inland states, while agriculturally induced wetland losses were similar in both groups. The proportionate declines of forested vs nonforested wetlands were not significantly different among states.  相似文献   

12.
Hathaway, Deborah L., 2011. Transboundary Groundwater Policy: Developing Approaches in the Western and Southwestern United States. Journal of the American Water Resources Association (JAWRA) 47(1):103‐113. DOI: 10.1111/j.1752‐1688.2010.00494.x Abstract: The western and southwestern United States include dozens of groundwater basins that cross political boundaries. Common among these shared groundwater basins is an overlay of differing legal structures and water development priorities, typically, with insufficient water supply for competing human uses, and often, a degraded ecosystem. Resolution of conflicts over ambiguously regulated groundwater has clarified transboundary groundwater policy in some interstate basins, while transboundary groundwater policy in international basins is less evolved. This paper identifies and contrasts approaches to transboundary groundwater policy, drawing from recent conflicts and cooperative efforts, including those associated with the interstate compacts on the Arkansas and Pecos Rivers; the Hueco and Lower Rio Grande Basins shared by New Mexico, Texas, and Mexico; and the Mexicali Basin in California and Mexico. Some efforts seek to fit groundwater policy into existing surface water allocation procedures; some strive for a better fit – incorporating scientific understanding of key differences between groundwater and surface water into policy frameworks. In some cases, neither policy nor precedent exists. The collective experience of these and other cases sets the stage for improved management of transboundary groundwater; as such, challenges and successes of these approaches, and those contemplated in several hypothetical model agreements, are examined.  相似文献   

13.
在风险社会背景下,环境治理的现代化需要多元共治,而要实现公众参与、发挥公众力量,首先要保障公众享有知情权。我国危险化学品专门立法中有关公众知情权的规定存在诸多问题:公众知情权的客体范围不明确,对政府信息公开义务的规定过于笼统,公众知情权的实现与救济途径不畅,政府未依法公开信息的法律责任不足。相较而言,美国在这一领域具有一定的探索经验。立足我国国情,本文参照域外美国《应急计划与公众知情权法案》,就公众知情权提出完善我国危险化学品专门立法的法制建议,以兹借鉴。  相似文献   

14.
Studies of irrigation drainage in the Western United States have documented some of the effects of irrigating land without first understanding and then considering implications from the interdependent relationships of hydrology, geology, geochemistry, biology, climatology, land use and socio-economic issues. In studies completed in 26 areas, selenium is the trace element found most often at elevated concentrations in water, bottom material and biota. Boron, arsenic, mercury and pesticide residues have also been found at elevated levels in some areas. Bioaccumulation of constituents associated with irrigation drainage is common. As the world experiences an explosive population growth, particularly in poorer countries, demands for food production from marginal, submarginal and newly irrigated soils are likely to cause severe adverse environmental impacts from allocation of limited water resources and contamination from irrigation drainwater. Cultivated marginal land is highly susceptible to degradation from soil erosion, salinization and waterlogging, not withstanding release of contaminants from application of irrigation water.  相似文献   

15.
Grass carp (Ctenopharyngodon idella Val.) were introduced into the United States in 1963 as potential biological control agents for nuisance aquatic weeds. Since that time an oftentimes bitter controversy has raged over its effects on sportfishing, and its possible natural reproduction and naturalization in North America. This review considers the history, ecology, and present status of grass carp in the United States in light of the voluminous scientific research conducted since its importation. Particular attention is given to the role of grass carp in the fisheries management plans of Arkansas. Recent development of a sterile, triploid grass carp hybrid may lead to widespread use of grass carp to control nuisance aquatic weeds in culturally eutrophicated waters of the United States.  相似文献   

16.
海南州气候变化对生态环境的影响及对策研究   总被引:3,自引:0,他引:3  
文章针对青海省海南州气象灾害频繁发生、草场退化、土地荒漠化、湖泊水位下降和河流流量减少等生态环境退化现象日益严重的实际,在广泛收集和整理气候、水资源、草地资源等生态环境因子资料的基础上,对海南州的主要气候要素、地表径流、水资源、植被的演替及其相互间的关系等主要生态环境变化特征进行了分析,为海南州经济社会协调发展提供了科学依据。  相似文献   

17.
Abstract: Growing populations, limited resources, and sustained drought are placing increased pressure on already over‐allocated water supplies in the western United States, prompting some water managers to seek out and utilize new forms of climate data in their planning efforts. One source of information that is now being considered by water resource management is extended hydrologic records from tree‐ring data. Scientists with the Western Water Assessment (WWA) have been providing reconstructions of streamflow (i.e., paleoclimate data) to water managers in Colorado and other western states (Arizona, New Mexico, and Wyoming), and presenting technical workshops explaining the applications of tree‐ring data for water management for the past eight years. Little is known, however, about what has resulted from these engagements between scientists and water managers. Using in‐depth interviews and a survey questionnaire, we attempt to address this lack of information by examining the outcomes of the interactions between WWA scientists and western water managers to better understand how paleoclimate data has been translated to water resource management. This assessment includes an analysis of what prompts water managers to seek out tree‐ring data, how paleoclimate data are utilized by water managers in both quantitative and qualitative ways, and how tree‐ring data are interpreted in the context of organization mandates and histories. We situate this study within a framework that examines the coproduction of science and policy, where scientists and resource managers collectively define and examine research and planning needs, the activities of which are embedded within wider social and political contexts. These findings have broader applications for understanding science‐policy interactions related to climate and climate change in resource management, and point to the potential benefits of reflexive interactions of scientists and decision makers.  相似文献   

18.
Large but feasible increases that have been projected for the production of wood energy in the United States can be expected to significantly alter the current carbon storage patterns in US forest vegetation. The 1976 net wood increment left after forest cutting equals about 136 × 106 tons of carbon/year, with about 60% of the increment found in merchantable trees, and the remainder in nonmerchantable components.Achieving 5–10 quads of wood energy beyond 1976 levels by the year 2010 can significantly change current carbon storage patterns with the magnitude of change dependent on the extent of residue harvest to meet energy goals, and the rate of future forest growth. Complete loss of the apparent net wood increment is a possible outcome.Although the future growth and harvest situation cannot be known now, a range of possible scenarios suggests that US forests in the year 2010 will store much less carbon than today, thus significantly changing their role in the global carbon cycle.  相似文献   

19.
Interviews were carried out with Japanese firms and environmental agencies regarding their current practices regarding life-cycle assessment (LCA). The results of this informal survey are compared with an executive survey of U.S. Fortune 500 companies. The findings show that Japanese LCA activity has increased rapidly over the past four years with several government agencies involved in LCA. Private industry has also founded LCA forums and recycling centers. The primary Japanese LCA interests include use in ecodesign and ecolabeling with the main environmental efforts focused on design for environment. Solid waste was identified as the most significant current environmental problem in Japan, in contrast to the United States where atmospheric and liquid discharges are ranked equally important. Neither the Japanese nor EPA plan to use LCA as a regulatory tool. This article summarizes several LCA case studies performed in Japan and lists the agencies involved in LCA development, ISO 14000, and ecoauditing/ecolabeling. Some recent Japanese legislation affecting LCA is also reviewed.  相似文献   

20.
Abstract: This paper provides an overview and summary of United States and Canadian federal, state, and provincial laws that offer some form of legal protection for environmental flows. Special attention is given to the new “second generation” law established in Texas and to ways western states are beginning to encourage transactions that help restore dewatered streams. Progress in the eastern states and some Canadian provinces to provide environmental flow protection is addressed. Based on this review, this paper presents recommended elements of a “model” environmental flow policy.  相似文献   

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