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481.
Nesting biodiversity conservation into landscape management 总被引:3,自引:0,他引:3
Eduardo R. Fuentes-Quezada Nikhil Sekhran and Arundhati Kunte-Pant 《Natural resources forum》2000,24(2):83-95
There is universal recognition that biological diversity (biodiversity) is being lost at an alarming rate. The costs and risks of these losses for humanity are still not fully understood, but are believed to be very significant. While much is being achieved through conservation programmes, the task of addressing the current crisis remains complex, particularly as there are significant biological, social and economic challenges to nesting conservation objectives into land-use management. This paper emphasizes the socio-economic challenges, wherein a central issue is that of equitably sharing the costs and benefits of conservation among all beneficiaries, nationally and internationally. The world's biological heritage supplies mankind with a number of ecological goods and services, which have attached direct use values, indirect use values, existence values and option values. Currently, only a few direct values are tangible and here much remains to be done to capture effectively and distribute equitably the benefits arising from the other values. The paper discusses three instances where some of these challenges are being addressed, in Belize, Pakistan and Mongolia. Finally, the paper discusses the need for additional mechanisms that will help meet the challenge of establishing and maintaining conservation arrangements in the landscapes of developing countries, where much of the most threatened biota is found. 相似文献
482.
High solids co-digestion of food and landscape waste and the potential for ammonia toxicity 总被引:1,自引:0,他引:1
A pilot-scale study was completed to determine the feasibility of high-solids anaerobic digestion (HSAD) of a mixture of food and landscape wastes at a university in central Pennsylvania (USA). HSAD was stable at low loadings (2 g COD/L-day), but developed inhibitory ammonia concentrations at high loadings (15 g COD/L-day). At low loadings, methane yields were 232 L CH4/kg COD fed and 229 L CH4/kg VS fed, and at high loadings yields were 211 L CH4/kg COD fed and 272 L CH4/kg VS fed. Based on characterization and biodegradability studies, food waste appears to be a good candidate for HSAD at low organic loading rates; however, the development of ammonia inhibition at high loading rates suggests that the C:N ratio is too low for use as a single substrate. The relatively low biodegradability of landscape waste as reported herein made it an unsuitable substrate to increase the C:N ratio. Codigestion of food waste with a substrate high in bioavailable carbon is recommended to increase the C:N ratio sufficiently to allow HSAD at loading rates of 15 g COD/L-day. 相似文献
483.
环湖片区是人与自然亲密相处的空间场所,具有丰富的自然资源和人文资源。环湖片区的景观生态规划可以协调人与自然及资源利用的关系。对石臼湖马鞍山环湖片区的生态环境基底和生态敏感性进行分析,确定重点规划区域;采用相对重要性指数(d I)识别落在规划区域内的重要斑块;运用最小耗费距离模型(MCR)模拟潜在生态廊道,并将其与景观廊道、游憩廊道相叠加;构建连续的景观生态格局,为石臼湖马鞍山环湖片区的景观生态规划提供依据和指导。结果表明,以景观生态学原理为指导,用客观定量的标准对景观要素进行选择和规划,使景观中资源组合在结构和功能上接近或达到最优化,提高区域内景观的稳定性,可以实现对环湖片区生态环境的有效保护。 相似文献
484.
Barbara M. Miller Julie Lellis 《Environmental Communication: A Journal of Nature and Culture》2016,10(2):249-268
A form of issue advocacy, marketplace advocacy campaigns often arise in response to burgeoning societal concerns, especially those faced by energy industries. Although these campaigns may include brief and selective references to corporate activities, most campaigns place a much stronger emphasis on commonly shared societal values. This study examines audience response to values-based environmental marketplace advocacy messages by the fossil fuel industries through a series of focus groups. Four instrumental values were identified in campaign videos (innovation, community, resilience, and patriotism), and the terminal value of pragmatism, especially as it relates to environmental issues, was identified as a result of identification with one or more of the instrumental values. The findings are discussed through the lens of extant research on marketplace advocacy and organizational values as well as Habermas's theory of refuedalization, shedding light on the ways corporations appeal to commonly held societal values in an effort to generate support for a given industry. 相似文献
485.
486.
487.
《Journal of environmental science and health. Part. B》2013,48(4):641-652
Abstract The key to any QSAR model is the underlying dataset. In order to construct a reliable dataset to develop a QSAR model for pesticide toxicity, we have derived a protocol to critically evaluate the quality of the underlying data. In developing an appropriate protocol that would enable data to be selected in constructing a QSAR, we concentrated on one toxicity end point, the 96 h LC50 from the acute rainbow trout study. This end point is key in pesticide regulation carried out under 91/414/EEC. The dataset used for this exercise was from the US EPA-OPP database. 相似文献
488.
The Expansion of Farm-Based Plantation Forestry in Vietnam 总被引:2,自引:0,他引:2
This study targets plantation forestry by farm households (small holders), which is increasing globally and most rapidly in
China and Vietnam. By use of an interdisciplinary approach on three study sites in Vietnam, we examined the trends in farmers’
tree planting over time, the various pre-requisites for farm-based plantation forestry and its impact on rural people’s livelihood
strategies, socio-economic status, income and security. The findings indicated a change from subsistence to cash-based household
economy, diversification of farmers’ incomes and a transformation of the landscape from mainly natural forests, via deforestation
and shifting cultivation, to a landscape dominated by farm-based plantations. The trend of transformation, over a period of
some 30 years, towards cash crops and forestry was induced by a combination of policy, market, institutional, infrastructural
and other conditions and the existence of professional farming communities, and was most rapid close to the industrial market. 相似文献
489.
武汉市主要年气候要素及其极值变化趋势 总被引:2,自引:0,他引:2
根据武汉市1951~2007年57年间主要气候要素及其极值的年序列(共17个),通过趋势分析和年代际比较分析,揭示武汉市气候变化对全球气候变化和当地城市化的响应。结果表明:武汉市5项气温均表现出一致的升温趋势,其中平均气温、平均最低气温、极端最低气温最明显,1970年代中后期升温速度加快; 4项降水要素变化均不显著,只有年降水日数接近信度01的显著性,其中年降水量为弱的增加趋势,同时有明显的年代际差异,1950、1980、1990等年代明显偏大(多),年降水日数、最大日降水量为减少趋势,但暴雨日数是增加的;年平均和最小相对湿度均呈现下降趋势,但年平均相对湿度达到极显著程度;平均风速、最大和极大风速以及大风日数一致性极显著减小;日照时数表现为减少趋势;年平均气压为先升后降,上升趋势不明显。可见武汉市各项气温、风速及其极值、相对湿度、日照时数等变化显著,降水、气压变化不显著,这些变化是全球气候变暖和城市化进程共同作用的结果. 相似文献
490.
Per Angelstam Michael Grodzynskyi Kjell Andersson Robert Axelsson Marine Elbakidze Alexander Khoroshev Ivan Kruhlov Vladimir Naumov 《Ambio》2013,42(2):129-145
Policies at multiple levels pronounce the need to encompass both social and ecological systems in governance and management of natural capital in terms of resources and ecosystems. One approach to knowledge production and learning about landscapes as social–ecological systems is to compare multiple case studies consisting of large spaces and places. We first review the landscape concepts’ biophysical, anthropogenic, and intangible dimensions. Second, we exemplify how the different landscape concepts can be used to derive measurable variables for different sustainability indicators. Third, we review gradients in the three dimensions of the term landscape on the European continent, and propose to use them for the stratification of multiple case studies of social–ecological systems. We stress the benefits of the landscape concepts to measure sustainability, and how this can improve collaborative learning about development toward sustainability in social–ecological systems. Finally, analyses of multiple landscapes improve the understanding of context for governance and management. 相似文献