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941.
Social goals and the valuation of natural capital 总被引:5,自引:0,他引:5
Costanza R 《Environmental monitoring and assessment》2003,86(1-2):19-28
Valuation ultimately refers to the contribution of an item to meeting a specific goal or objective. Conventional economic valuation is based on the goal of allocative efficiency. But other social goals may be equally, if not more, important. For example, the goals of social fairness and ecological sustainability have been identified as being at least of the samelevel of importance as allocative efficiency. This paper looks atthe role of social goals in determining the basis for valuation ofnatural capital and ecosystem services, and sketches the characteristics of a system of valuation that would give equal weight to all three of the major social goals mentioned above. It also places these goals within a more comprehensive conceptualmodel of the economy and its relationship to the ecological lifesupport system in which it is embedded. 相似文献
942.
Ian D. Thompson 《Environmental monitoring and assessment》2006,121(1-3):261-271
The general principles of scale and coarse and fine filters have been widely accepted, but management agencies and industry are still grappling with the question of what to monitor to detect changes in forest biodiversity following forest management. Part of this problem can be attributed to the lack of focused questions for monitoring including absence of null models and predicted effects, a certain level of disconnect between research and management, and recognition that monitoring can be designed as a research question. Considerable research from the past decade has not been adequately synthesized to answer important questions, such as which species or forest attributes might be the best indicators of change. A disproportionate research emphasis has been placed on community ecology, and mostly on a few groups of organisms including arthropods, amphibians, migratory songbirds, and small mammals, while other species, including soil organisms, lichens, bats, raptors, some carnivores, and larger mammals remain less well-known. In most studies of community ecology, the question of what is the importance, if any, of the regularly observed subtle changes in community structures, and causes of observed changes is usually not answered. Hence, our ability to deal with questions of persistence is limited, and demographic research on regionally--defined key species (such as species linked to processes, species whose persistence may be affected, species with large home ranges, species already selected as indicators, and rare and threatened species) is urgently needed. Monitoring programs need to be designed to enable managers to respond to unexpected changes caused by forest management. To do this, management agencies need to articulate null models for monitoring that predict effects, focus fine--scale monitoring on key species (defined by local and regional research) in key habitats (rare, declining, important) across landscapes, and have a protocol in place to adapt management strategies to changes observed. Finally, agencies must have some way to determine and define when a significant change has occurred and to predict the persistence of species; this too should flow from a well--designed null model. 相似文献
943.
利用美国陆地资源卫星TM5遥感信息,调查分析了鞍山市森林资源现状。结果表明,鞍山市共有森林资源466933.52hm^2,占全市土地面积的50.32%,其中灌木林占森林面积的81.11%。在此基础上,分析了存在的主要问题,并提出了恢复途径及生态建设模式。 相似文献
944.
Malgorzata Kwiecień 《Environmental monitoring and assessment》1997,46(3):191-207
A new, direct method was developed for quantifying inorganic particulate aerosols trapped by the forest canopy, and for determining the resulting input of elements to a forest ecosystem. The method is based on direct measurements of only six parameters. Using this method, it is possible to determine the load of aerosols trapped by the forest canopy and deposited to leaves, as well as the load of aerosols falling to the forest floor by impaction on plants. It is also possible to estimate the aerosol input of soluble and insoluble elements to an ecosystem. With this new method it has been found that the load of aerosols trapped by the canopy of a mixed forest located in the Rybnik Coal Basin averaged 189.0 kg x ha-1 x growing season-1, or 39.3% of the total inorganic particles reaching the ecosystem. The trapped aerosols provided 13.4 kg x ha-1 of soluble nitrogen and 0.91 kg x ha-1 of insoluble nitrogen over the growing season. At the same time, the input of soluble nitrogen from the atmosphere with rainfall to an open area averaged 13.9 kg x ha-1, and the input of insoluble nitrogen with inorganic dusts averaged 1.4 kg x ha-1. 相似文献
945.
荒漠生态系统监测研究指标体系 总被引:3,自引:0,他引:3
新疆环境保护科学研究所自1984年接受“荒漠生态系统监测指标体系的观测研究”课题,在乌鲁木齐北部90km处的沙漠边缘建立了“准噶尔沙漠生态系统定位研究站”,自1987年正式开展了“荒漠生态系统定位观测研究”工作,从古尔班通沙漠中部至天山博格达峰中山带选定了沙漠、沙漠边缘、山前洪冲积扇、前山和中山带五个观测场,沙漠四季进行定位观测,同时,在站内进行多项目的连续观测,现集五年观测研究经验,结合中国科学院及国外研究站的先进经验,建立了荒漠生态系统指标体系。 相似文献
946.
Ozone biomonitoring is a detection and monitoring techniquethat involves documenting ozone-induced visible injury toknown ozone-sensitive species under conditions of ambientexposure. The USDA Forest Service administers a long-term,nationwide ozone biomonitoring program to address public andscientific concerns about ozone impacts on forest health. Asystematic grid is used as the basis for biomonitoring sitelocations. At each site, trained field crews evaluate amaximum of thirty plants of up to six species and record the amount and severity of leaf-injury on individualplants. Injury from ozone was found more often on biomonitoring sites in the eastern Unites States than in theinterior or west-coast areas. Further results from thenortheast reveal that in any year, there is a higherpercentage of ozone-injured plants with more severe symptomsin areas with relatively high ozone concentrations than inareas with relatively low ozone. In very dry years (e.g.,1999) the percentage of injured plants and injury severityestimates are both sharply reduced even though ambient ozoneexposures are high. These findings demonstrate thatbiomonitoring data provide meaningful evidence of when highozone concentrations during the growing season have biologicalsignificance. Any assessment of ozone stress in the forestenvironment must include both biomonitoring (i.e., plantresponse) and air quality data to be complete. 相似文献
947.
生态系统健康评价的研究进展 总被引:4,自引:0,他引:4
回顾了生态系统健康的概念,阐述了水生态系统健康评价的三种指标体系:指示物种指标体系、结构功能指标体系、V-O-R指标体系.其中,结构功能指标体系从选取指标和指标分类两方面进行了方法归纳,分析了生态系统健康的几种评价方法,以及讨论了生态系统健康研究中存在的问题和发展趋势. 相似文献
948.
Worldwide, paper production is a major industry that contributes about 3 percent of Gross World Product. The paper cycle involves a broad range of natural resource and environmental impacts because fiber supply relies on trees, paper manufacturing requires fuel inputs, and paper waste disposal can contribute to emissions of the potent greenhouse gas (GHG), methane (CH4). In some countries, the paper cycle may be seen as a net sink for GHG because of reliance on renewable wood by-products and the maintenance of forest plantations. On a worldwide basis, however, this study demonstrates that the paper cycle is a significant contributor to GHG emissions, adding emissions at least comparable in magnitude to that of Australia each year. The estimated global warming contribution of paper in landfills is estimated to be similar to that of paper manufacturing processes, on a heating-equivalent basis. In some temperate regions, original old-growth forests are still harvested to supply pulpwood, resulting in a significant loss of carbon (C) storage. In theory, the paper cycle holds the promise of achieving zero net emissions if pulpwood production, consumption and disposal are carefully managed. In practice, even stabilization of emissions at current levels would be challenging and entail changes comparable to a 20 percent reduction in CH4 generation from landfilled paper, and a 2.5 percent annual increase in plantation establishment would be needed to offset the projected increase in emissions from paper manufacturing. 相似文献
949.
生态系统调节水量的价值评估——兴山实例 总被引:8,自引:0,他引:8
根据植被类型、坡度和土壤类型,分析了兴山县集水区内不同植被地块调节水量的能力。并且根据水能学的原理,分析了枯水期和洪峰期葛洲坝水电站的发电量与水流量的关系,建立了水流发电模拟模型。在上述分析的基础上,评估了兴山县境内生态系统调节香溪河等河流的水量,改善长江全年来水的均匀度,提高葛洲坝水电站发电效率的经济价值。 相似文献
950.
观音坪电站工程评价区景观格局预测分析 总被引:3,自引:0,他引:3
以湖北省宣恩县酉水流域观音坪水电工程生态完整性评价报告为基础,采用卫星遥感图片分析,运用GIS技术,完成土地利用结构和景观格局图。通过对工程建成前后各种土地类型的优势度值的变化分析得出:工程建设中会造成林草地减少约3.45hm2,优势度由原来的58.30%下降到57.41%,仅下降0.89%;林地和耕地也分别减少约7.20 hm2和0.84 hm2,优势度下降3.87%和1.92%;而水域增加10.82 hm2,优势度上升1.73%,但是它们之间的比例关系基本与工程建设前的比例相当,草地仍然是景观生态体系中的模地。工程建设后当地景观生态体系不会有很大变化。 相似文献