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741.
Over the past ten years, efforts have been made in the Paraty region of Brazil towards more active state governance of coastal resources through the implementation and enforcement of various types of protected areas. Trindade is one of the communities making efforts to advocate for themselves as the key stakeholders in a negotiation process for a no-take protected area management plan. As is happening across South America, there has been a shift in policy in Brazil towards participatory environmental governance practices. The objective of this paper is to analyze the quality of community participation in a resource governance process, the perceptions of participating and non-participating community members, and the actual influence of community participants on the protected area management plan under review (in 2012/2013). The research was conducted as interdisciplinary action research. Data were collected through a qualitative approach, using mixed methods of narratives, interviews, focus groups, participant observation and workshops. The negotiation process and community participation in this negotiation process was studied through observation of meetings. Analysis of the negotiation process revealed the importance that community participants place on their rights as Caiçaras, and four further key themes emerged; communication disconnect, opportunity and capacity to participate, representation and decision-making, and conflict. Meaningful participation in natural resources management has not yet been achieved in the process reviewed. The process described is the initial phase of a long-term relationship between community members and government authorities, and changes need to be made so that the desired outcomes for natural resources management are more likely to be achieved. 相似文献
742.
着重说明自然灾害经济评价中利用影子价格的原因,简要说明我国目前在投资项目评价中采用的影子价格及计算方法,以及在自然灾害经济评价中如何利用影子价格进行计算. 相似文献
743.
Frederico Neto 《Natural resources forum》2001,25(4):285-297
Floods were by far the most damaging type of natural disasters during the 1990s, in terms of both human impacts and socio-economic losses. Vulnerability to flooding disasters around the world is almost always differentiated by the socio-economic conditions of different income groups in the disaster area. In general, the poorer the income group (or the country) the more vulnerable it is likely to be to the adverse impacts of floods. The article argues that Bangladesh is the world's most flood-prone developing country in terms of the relative socio-economic impacts of floods. While conventional flood control strategies tend to be based on structural engineering approaches—such as the construction of large-scale embankments, diversion canals and dams—this article argues that more emphasis should be given to alternative, non-structural measures. The main lesson from recent flooding disasters in Bangladesh is that, in the absence of expensive structural measures, many non-structural ones can go a long way towards reducing vulnerability to and mitigating the impacts of floods. 相似文献
744.
From open access to access by all: restating challenges in designing groundwater management in Andhra Pradesh, India 总被引:1,自引:1,他引:0
In a village-based watershed in Andhra Pradesh, India, it is increasingly difficult for users to access and extract groundwater for irrigation: a 'pumping race' is taking place. A move from groundwater development towards groundwater management is required, with a new perspective on options for change. Through a study of borewell technology and groundwater use, and considering new local developments in electricity supply and participatory resource management, the article argues that groundwater is a resource with 'instructions for use'. The technological dimensions of groundwater irrigation urge its study as a socio-technical process in order to design sustainable and equitable groundwater management. 相似文献
745.
746.
西气东输工程的环境协同效应研究 总被引:2,自引:0,他引:2
协同效应研究是气候变化政策研究的新领域,也是非常重要的领域.西气东输工程的主要目的是为我国中东部地区输送丰富的天然气资源,但其实施同时也有助于减少东部地区大气污染物排放,改善大气质量.利用较成熟的中国区域环境与经济综合评价模型(AIM-LOCAL/China模型),从用气项目的SO2和CO2排放的常规情景(BAU)和利用天然气后的情景(NGS)两方面进行了量化比较,分析西气东输工程的环境协同效应.研究发现:在用气项目的范围内,NGS情景下的SO2排放相比BAU情景明显减少,同时CO2等温室气体排放也大幅减少.2003-2020年,累计可以减排约312×104 t SO2和3 475×104 t CO2,分别比BAU情景减排40.5%和17.9%.从4个用气部门来看,不论是SO2还是CO2,电力部门用气项目的减排量都占突出位置. 相似文献
747.
748.
The effects of natural zeolite (clinoptilolite, NZ) and synthetic zeolite (Y, SZ) on salinity and the presence of the harmful salts in the soil were compared on Raphanus sativus L. Nine soil treatments were studied: 1 (control), 2 (NaCl), 3 (Na2SO4), 4 (NZ), 5 (SZ), 6 (NZ?+?NaCl), 7 (SZ?+?NaCl), 8 (NZ?+?Na2SO4), and 9 (SZ?+?Na2SO4). Five radish seeds were planted in each pot. Each treatment was repeated 10 times. After 50 days under equal conditions some parameters consisting of the number of leaves (NL), total leaf area (TLA), total fresh weight (TFW), total dry weight (TDW), root fresh weight (RFW), air fresh weight (AFW), root dry weight (RDW) and air dry weight (ADW) were determined. Results showed that adding either NZ or SZ to salinic soil (treatments NZNaCl, NZNa2SO4, SZNaCl and SZNa2SO4) increased AFW, TFW and TDW. Using both NZ and SZ in normal soil increased the weight of plants by developing AFW. Further NZ was more effective on soil with NaCl than SZ. 相似文献
749.
Microbial nitrogen transformation potential in surface run-off leachate from a tropical landfill 总被引:1,自引:0,他引:1
Ammonium is one of the major toxic compounds and a critical long-term pollutant in landfill leachate. Leachate from the Jatibarang landfill in Semarang, Indonesia, contains ammonium in concentrations ranging from 376 to 929 mg N L−1. The objective of this study was to determine seasonal variation in the potential for organic nitrogen ammonification, aerobic nitrification, anaerobic nitrate reduction and anaerobic ammonium oxidation (anammox) at this landfilling site. Seasonal samples from leachate collection treatment ponds were used as an inoculum to feed synthetic media to determine potential rates of nitrogen transformations. Aerobic ammonium oxidation potential (<0.06 mg N L−1 h−1) was more than a hundred times lower than the anaerobic nitrogen transformation processes and organic nitrogen ammonification, which were of the same order of magnitude. Anaerobic nitrate oxidation did not proceed beyond nitrite; isolates grown with nitrate as electron acceptor did not degrade nitrite further. Effects of season were only observed for aerobic nitrification and anammox, and were relatively minor: rates were up to three times higher in the dry season. To completely remove the excess ammonium from the leachate, we propose a two-stage treatment system to be implemented. Aeration in the first leachate pond would strongly contribute to aerobic ammonium oxidation to nitrate by providing the currently missing oxygen in the anaerobic leachate and allowing for the growth of ammonium oxidisers. In the second pond the remaining ammonium and produced nitrate can be converted by a combination of nitrate reduction to nitrite and anammox. Such optimization of microbial nitrogen transformations can contribute to alleviating the ammonium discharge to surface water draining the landfill. 相似文献
750.
Peter F. Ffolliott D. Phillip Guertin William D. Rasmussen 《Environmental management》1988,12(6):809-814
Recurrent fire has played a dominant role in the ecology of southwestern ponderosa pine forests. To assess the benefits or losses of fire in these forests, a computer simulation model, called BURN, considers vegetation (mortality, regeneration, and production of herbaceous vegetation), wildlife (populations and habitats), and hydrology (streamflow and water quality). In the formulation of the model, graphical representations (time-trend response curves) of increases or losses (compared to an unburned control) after the occurrence of fire are converted to fixedterm annual ratios, and then annuities for the simulation components. Annuity values higher than 1.0 indicate benefits, while annuity values lower than 1.0 indicate losses. Studies in southwestern ponderosa pine forests utilized in the development of BURN are described briefly. 相似文献