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排序方式: 共有149条查询结果,搜索用时 15 毫秒
1.
Journal of Material Cycles and Waste Management - The present research work focused on fabricating Biodegradable Plate (BD plate) composed of rice husk ash, bagasse and corn starch which is...  相似文献   
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Environment, Development and Sustainability - Drying of fish at the Sagar Island (21.7269° N, 88.1096° E) is generally carried out in open sun on the seashore on plastic sheets or mat of...  相似文献   
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Traditional knowledge and practices are important in prudent resource use and biodiversity conservation. The implications of modernization and changing lifestyle are discussed in the context of agriculture and resource use, the two sectors in which maximum modernization has occurred. The information was gathered through observations and structured interviews over three years (July 1996 to July 1999) of field work in the western Himalaya. It was observed that forest based subsistence agriculture has given way to the market dependant cash crop cultivation. That apart from loss of genetic diversity, has also resulted in the degradation of forests. The use of wild plants in the day-to-day activities has also declined and dependence on high value market products has increased. Currently, wild plants are used only if no other cheap substitute is available in the market or if the use is economically beneficial to the people. Thus, the knowledge gathered through ages of experience is eroding because of the activities geared for short-term economic benefits which, in long run, may not be sustainable.  相似文献   
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This paper explores linkages between food security and crisis in different contexts, outlining the policy and institutional conditions needed to manage food security during a crisis and to rebuild the resilience of food systems in periods of relative peace. The paper reviews experiences over the past decade of countries in protracted crisis and draws lessons for national and international policy. It assesses the different alternatives on offer in fragile countries to address, for example, the disruption of institutional mechanisms and the decreasing level of support offered by international donors with respect to longer-term expectations. It proposes a Twin Track Approach to enhance food security resilience through specific policies for protracted crises that link immediate hunger relief interventions with a long-term strategy for sustainable growth. Finally, the article analyses policy options and the implications for both short- and longer-term responses vis-à-vis the three dimensions of food security: availability; access; and stability.  相似文献   
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Thespesia populnea oil was new source of biodiesel. Crude Thespesia populnea oil was used as feedstock for biodiesel production by alkali-catalyzed methanolysis. The reaction in the presence of NaOH as catalyst was carried out to investigate the optimum conditions and to study the effects of variables on the reaction. A methanol to oil ratio of 6:1, sodium methoxide catalyst concentration of 1.5%, mixing intensity of 250 rpm and reaction temperature of 60°C offered the best Thespesia populnea seed oil methyl esters (biodiesel) yield (92.6%). The methyl ester content under these optimum conditions was 92.6% w/w, and all of the measured properties of the Thespesia populnea biodiesel (TPME) met the international standards ASTM D 6751-02. The results reveal that all of the reaction variables in this study had positive effects on the reaction. The results of the present study indicated that TPME could be a potential alternative to petrodiesel  相似文献   
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Biodiversity conservation has undergone a profound change in philosophy, policies and management approaches over the last forty years. The traditional top–down approach to nature protection has been widely criticized for failing to include critical social elements in management practices, and is being gradually replaced by a slew of participatory strategies under the rubric of bottom-up conservation. The new approach recognizes local communities as key partners in wildlife management and seeks their participation in social development and biodiversity conservation. However, every social context is different in its structure and functions, and in the way social groups respond to calls for participation. In order to gain a better understanding of the approach and the barriers encountered in its implementation, a questionnaire survey of 188 households was employed in the communities of the Upper Mustang extension of Annapurna Conservation Area (ACA) in Nepal. The study provides a comparative analysis of community participation and its barriers between Non-Tourist (NT) and Tourist (TV) villages. The results revealed important differences between the two groups in terms of their participation in community programs, barriers to participation, and perception of benefits from participation. Owing to their distinct spatial, demographic and attitudinal differences, the two village groups have their own sets of needs, values and motivation factors which cannot be generalized and treated as such. The research clearly identifies the need for the conservation agency to be creative in devising strategies and initiatives appropriate to specific social groups so as to optimize their input in participatory conservation.  相似文献   
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Taxus wallichiana Zucc. (Himalayan yew) represents one of the most threatened medicinal tree species of the Himalayan region. Heavy exploitation of its bark and leaves for taxol® has resulted in decline in its population. Generating quantitative information on Himalayan yew has therefore been stressed. The present paper provides information on the population and bark removal of Himalayan yew from one of the interior areas of Himalaya. Total count and quadrat method were deployed to generate quantitative information on its population while bark removal was estimated based on depth and extent of bark removed. After analyzing the existing information and the results of the study, a rapid vulnerability assessment (RVA) of the species was carried out. Taxus reported a density of 72 individuals/ha and was present as an under canopy of Picea smithiana. Complete stripping of bark was observed in 11 % of the Taxus population which amounted to ca. 18,152.86 cm3 of bark removed. The age class distribution showed complete absence of seedlings and saplings. RVA scores also reported higher values (26) thereby pointing toward the high vulnerability of this species. Across its entire distributional range, Taxus population is under severe pressure. It is high time when few patches of Taxus are demarcated as Medicinal Plant Conservation Areas, and detailed studies on its autecology are initiated.  相似文献   
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