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971.
972.
973.
This paper examines the impact of various social, economic and political changes on the work of the Indian Forest Service, the elite organization concerned with environmental management in India. It is noted that whilst many leading authors criticize this organization, nobody has taken the time to analyse the role of the Indian Forest Service and the way it has responded to the many challenges it has faced in the last 20 years. This paper seeks to rectify this by focusing on three key challenges: (1) due to economic liberalization the actual work that the forest officer is expected to undertake has changed beyond recognition; (2) political manipulation and correspondingly accusations of corruption have increased; (3) social changes and their impact on recruitment into the Indian Forest Service. It is concluded that, despite the many challenges which the Indian Forest Service has faced over the years, it is remarkably resilient and remains the most powerful agent in rural India.  相似文献   
974.
This article addresses the removal of methyl tertiary‐butyl ether (MTBE) from water, using Fenton's Reagent. Although complete mineralization of MTBE by Fenton's Reagent was not achieved, greater than 99 percent destruction of MTBE was realized. This was accomplished at a Fe+2:H2O2 ratio of 1:1 and 1 hour of contact time. In all tests, twice the stoichiometric ratio of H2O2 to MTBE was used. The major by‐products were tertiary‐butyl alcohol, tertiary‐butyl formate, and acetone with traces of 2‐methyl‐1‐propene (isobutylene). While small quantities of O2 evolved, no significant quantity of CO2 gas was detected.  相似文献   
975.
976.
The Gasplasma® process developed by APP is an advanced thermal conversion (ATC) technology which has been developed for the treatment of household and trade wastes and has also been successfully applied to the handling of wastes derived from landfill and would be capable of achieving effective energy conversion when utilised as an integrated part of the Enhanced Landfill Mining (ELFM) concept.The core Gasplasma® technology comprises a two-stage thermal treatment system—firstly, a fluidizing bed gasifier which converts the wastes to a crude syngas using oxy-steam and, secondly, a plasma converter that efficiently cracks problematic tars in the raw syngas to produce a reformed and clean syngas suitable for generating electrical power in gas engines and also recovering an environmentally stable vitrified product for use as a secondary aggregate material. The utilization of oxy-steam as a gasifying agent greatly reduces the syngas volume compared to other ATC processes and incineration and hence reduces the cost of the gas cleaning system while improving the efficiency of the process. By adopting this two-stage approach, high energy conversion (74–90%) and carbon conversion (95 ± 1.6%) efficiencies were achieved with the Gasplasma® plant that compare favourably with published efficiencies data. The calculated net exportable power generation efficiency for a commercial scale plant is significantly in excess of 25%. This compares well with the published figures of 17.7–23% for fluidized bed technologies processing MSW.  相似文献   
977.
Ko koe ki tēnā, ko ahau ki tēnai kīwai o te kete (you at that, and I at this handle of the basket). This Māori (New Zealanders of indigenous descent) saying conveys the principle of cooperation—we achieve more through working together, rather than separately. Despite decades of calls to rectify cultural imbalance in conservation, threatened species management still relies overwhelmingly on ideas from Western science and on top-down implementation. Values-based approaches to decision making can be used to integrate indigenous peoples’ values into species conservation in a more meaningful way. We used such a values-based method, structured decision making, to develop comanagement of pekapeka (Mystacina tuberculata) (short-tailed bat) and tara iti (Sternula nereis davisae) (Fairy Tern) between Māori and Pākehā (New Zealanders of European descent). We implemented this framework in a series of workshops in which facilitated discussions were used to gather expert knowledge to predict outcomes and make management recommendations. For both species, stakeholders clearly stated their values as fundamental objectives from the start, which allowed alternative strategies to be devised that naturally addressed their diverse values, including mātauranga Māori (Māori knowledge and perspectives). On this shared basis, all partners willingly engaged in the process, and decisions were largely agreed to by all. Most expectations of conflicts between values of Western science and Māori culture were unfounded. Where required, positive compromises were made by jointly developing alternative strategies. The values-based process successfully taha wairua taha tangata (brought both worlds together to achieve the objective) through codeveloped recovery strategies. This approach challenges the traditional model of scientists first preparing management plans focused on biological objectives, then consulting indigenous groups for approval. We recommend values-based approaches, such as structured decision making, as powerful methods for development of comanagement conservation plans between different peoples.  相似文献   
978.
要减少/消除危险物资和产品的生成,世界需要更多的资源.发达国家一直在增加的危险废物生成需要靠强制手段来缩减.当前实行的危险废物再生办法是不可持续的.当今最重要的两种危险废物贸易,一是废船解体业(经常出现在亚洲拆解厂),二是电子垃圾从大多数高度工业化国家出口到发展中国家处理.这每一种活动,都对人类健康和环境有严重影响.  相似文献   
979.
Abstract

The coastal water of northeast Taiwan island, called ‘Yin-Yang Hai’ for its distinct yellow colour compared with blue offshore water, was investigated from 1989 to 1990 by the authors. Biological study showed the dominant species of plankton to be Copepoda, Cladocera, planktonic eggs and Diatoma. Dominant species of benthos were young crabs, Amphipoda and Annelida, with Amphipoda usually occurring in heavily polluted areas. Heavy metal data showed that the concentration of copper was high. the copper and iron concentration in algae of the intertidal zone was also high. the concentrations of iron and copper in inshore water were also higher than in offshore water. By comparison of the pH and salinity distribution of this area, we conclude that this coastal water has been polluted by acid waste water from coastal industry. the suspended solids concentration in sea water is high. Flocculation occurring at the boundary of fresh and saline water might be a reason for the distinct yellow colour of the water of this area. Further study is required.  相似文献   
980.
The benthic ecological structure of the Tan-Shui estuary, Taiwan is changed due to long term effects of dumping of urban wastewater and of engineering actions. to monitor these changes, we sampled and analyzed benthos and sediment from 12 stations on the estuary.

The composition of the dominant species of benthos varied seasonally, with molluscan and crustacean species having greater numbers and higher frequencies of occurrence than other species. the dominant taxa during winter were Nassarius sp. and Maldanidae at two stations. Analysis using Simpson's index and Shannon's index showed the benthic community varied more in coastal areas than in offshore areas.

Physicochemical analysis showed that most of the Tan-Shui estuary consisted of sandy sediment. the variations in concentrations of organic carbon and total nitrogen at each station were small. Although the concentrations of chlorophyll-a and carotenoid at all stations were generally low, the two stations had the highest concentrations, and we concluded that the concentration of pigments in these sediments was related to the abundance of benthos. the community structure of the benthos reflected the characteristics of the sediments, and benthic species exhibited selection of and adaptation to specific sedimentary environments.  相似文献   
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