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71.
SUMMARY

An approach to the rehabilitation of degraded community lands built on people's perceptions and traditional knowledge was developed, implemented on a small scale (6 ha plot), and evaluated in terms of economic and ecological costs and benefits over a period of 5 years in a mid-altitude (1200 m) village of Garhwal Himalaya. Rehabilitation comprised establishment of water harvesting tanks, organic management of soil, agroforestry (native multipurpose trees t traditional crops), and decision making by the whole village community. Costs and benefits under irrigated and unirrigated conditions were compared. The total cost of establishing the irrigated agroforestry system was 1.23 fold that of the unirrigated one, whereas the total benefit was 2.09 fold. The average standing above-ground biomass of the 4-year-old plantation in the irrigated agroforestry system was 11.69 t/ha compared to 8.34 t/ha in the unirrigated system. Improvement in soil properties was more pronounced in the irrigated system than in the unirrigated one. Nutrient input, an input derived largely from forest biomass, in the unirrigated system was nearly 3 times higher than that in the irrigated system. It is concluded that, considering the local and national/regional/global interests in an integrated manner, agroforestry incorporating water management would be a more effective option for rehabilitating degraded community lands than the afforestation currently being attempted by the government in the mid-altitudes of Indian Himalaya.  相似文献   
72.
《Environmental Hazards》2013,12(3):266-283
This paper focuses on identifying examples of first-order system interactions, which make important contributions to building coastal resilience for coastal zone management. This discussion is based on an application of the Institutional Analysis and Development Framework to a case-study analysis of coastal management in South Australia. The study suggests that cross-scale interactions and informal relationships within and between users and managers are key interactions defining resilience outcomes within the current system. A significant constraint on improving resilience was the lack of evaluative criteria for identifying sustainable forms of system behaviour. The paper argues that resilience is a function of a normative statement on the characteristics desirable in the functioning system. Analyses of coastal resilience, which facilitate greater understanding of the range of complexities in coastal behaviour, are therefore central to gaining the most useful insights into the options and pathways for building more sustainable coastal futures.  相似文献   
73.
论文利用文献计量学方法定量分析了土壤质量研究领域的科学文献,结果显示国际土壤质量研究热点从有机质及其组分对管理措施的响应、微生物指标敏感性、土壤质量定义到土壤质量评价方法、评价指标和框架的完善,在农业生产和环境保护中的应用性不断加强。目前,土壤质量的监测及其对土壤修复、全球气候变化的响应是未来研究热点。主要研究趋势有:1)发展中国家将在土壤质量研究领域中发挥重要作用;2)土壤质量对土壤修复、全球气候变化的响应以及应对措施成为未来的研究重点;3)可持续发展仍然是土壤质量研究的主题,不同国家及地区应根据自身特点进行土壤质量评价、监测、修复研究,制定法律,保障土壤管理的规范化和可持续化。  相似文献   
74.
Abstract:  There is a pressing need to find both locally and globally relevant tools to measure and compare biodiversity patterns. Traditional ecological knowledge (TEK) is important to biodiversity monitoring, but has a contested role in preliminary biodiversity assessments. We examined rapid participatory rural appraisal (rPRA) (a tool commonly used for local needs assessments) as an alternative to surveys of vascular plants conducted by people with local knowledge. We used rPRA to determine the local-knowledge consensus on the average richness, diversity, and height of local grasses and trees in three habitats surrounding Boumba, Niger, bordering Park-W. We then conducted our own vascular plant surveys to collect information on plant richness, abundance, and structure. Using a qualitative ranking, we compared TEK-based assessments of diversity patterns with our survey-based assessments. The TEK-based assessments matched survey-based assessments on measures of height and density for grasses and trees and tree richness. The two assessments correlated poorly on herb richness and Simpson's D value for both trees and grasses. Plant life form and gender of the participant affected the way diversity patterns were described, which highlights the usefulness of TEK in explaining local realities and indicates limitations of using TEK as a large-scale assessment tool. Our results demonstrate that rPRA can serve to combine local-knowledge inquiry with scientific study at a cost lower than vascular plant surveys and demonstrates a useful blunt tool for preliminary biodiversity assessment.  相似文献   
75.
Invoking expert knowledge is a common strategy in attempts to settle environmental disputes. However, the validity of expertise is contingent upon the context in which an actor is recognised as an expert. In complex environmental conflicts the distinction between lay and expert knowledge is not always fixed a priori. However, as conflicts unfold, intervening parties tend to present their cases in ways that reinforce this distinction. This is apparent in the attribution of environmental responsibilities. This paper presents an empirical case of an environmental conflict related to land contamination due to coal ash disposal in Bosnia and Herzegovina. The analysis revealed two polar positions in the conflict: the first one, mainly held by scientists and industry representatives, invoked expert knowledge and presented a distributed approach to the attribution of responsibilities; the second one, mainly held by local residents and municipal officials, presented an experiential understanding of pollution, as lay knowledge, and attributed direct responsibilities to the local energy industry. The paper concludes that the persistence of the distinction between expert and lay knowledge is a manifestation of the social structures that underlie the conflict.  相似文献   
76.
The aim of this paper is to understand how local residents participate in the construction of local environmental problems and to evaluate a particular analytical approach in environmental sociology to study this phenomenon. The paper is based on an interview study with a sample of local residents. The analysis demonstrates how the local residents attempt to construct a local environmental problem. In particular, the study focuses on how involved actors are positioned, how different sorts of knowledge claims are used, and how the neglect the residents perceive from the authorities affects the attempt to construct a local environmental problem. The study shows that the local residents play a central role in the construction of the situation and that the evaluated model could be very helpful as an analytical tool in the investigation of local residents' participation in the construction of environmental problems.  相似文献   
77.
ABSTRACT: Reservoir flood control is operated in real time so finding the optimal solution is unnecessary since it may not be practical. The key to reservoir flood control operation is quickly generating some feasible and effective alternatives and then selecting one among them. A fuzzy iteration methodology, which gives the objective weight and the relative membership degree of alternatives at the same time, is presented. Since the weight and relative membership degree are directly acquired from the recommended alternatives provided by decision makers, the results are more reasonable and realistic. Besides, the difficulty in giving weights is also avoided. With the aid of a robust and flexible decision support system, the effectiveness of decision making can be improved.  相似文献   
78.
Finding Hope in the Millennium Ecosystem Assessment   总被引:1,自引:0,他引:1  
Abstract:  Over the past quarter century, a new scientific activity has emerged: collective assessments by large numbers of scientists from different disciplines combining their expertise to better understand human interrelations with nature and to inform policy. The Millennium Ecosystem Assessment exceeded all such assessments before it in both the breadth of its coverage and the depth of its analysis of socioecological system dynamics. The findings are not encouraging. Nearly all ecosystems are being degraded and will continue to be degraded for decades to come even if policy changes are initiated now. For scientists participating in the assessment, the MA had another disconcerting aspect. It clearly shows that our fragmented, disciplinary knowledges cannot simply be combined to form an understanding of a whole complex system. Counterbalancing the despair of the findings and scientific difficulties of aggregating specialized knowledges, the MA demonstrated the potential of a deliberative democratic approach to grappling with complex problems .  相似文献   
79.
对大气污染总量控制规划智能决策支持系统的开发步骤和总体结构做了介绍。并描述了该系统中的知识库系统、模型库系统、数据库系统和图形库系统的设计思想,特别是对知识库的构造进行了较详细的叙述。还介绍了神经网络技术在该系统中的应用。指出大气污染总量控制规划智能决策支持系统将为大气污染总量控制提供更科学、更合理、更有效的规划方案。  相似文献   
80.
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