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121.
Nsajig wa E.Mbije Gregory M.Wagner Julius Francis Marcus C.Ohman Kajsa Garpe 《Ambio-人类环境杂志》2002,31(8)
东非珊瑚礁的特点是它位于一个离散的动物地理学分区[1],具有经由赤道流接纳和重新分配偏远的种属物质的潜在重要性[2].尽管如此,该地区仍然是世界上研究最少的地区之一.例如,在坦桑尼亚,尽管珊瑚礁是众多的人赖以为生的重要自然资源,却没有受到应有的重视和研究[3~5].为数不多的研究定量分析过坦桑尼亚的珊瑚礁结构[6~13],而且大部分只是限于对一些礁砰进行基线研究. 相似文献
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G. Gal M.R. Hipsey A. Parparov U. Wagner V. Makler T. Zohary 《Ecological modelling》2009,220(13-14):1697-1718
The need for scientifically based management of lakes, as key water resources, requires the establishment of quantitative relationships between in-lake processes responsible for water quality (WQ) and the intensity of major management measures (MM, e.g. nutrient loading). In this paper, we estimate the impact of potential changes in nutrient loading on the Lake Kinneret ecosystem. Following validation of the model against a comprehensive dataset, we applied an approach that goes beyond scenario testing by linking the lake ecosystem model DYRESM–CAEDYM with a set of ecosystem variables included in a pre-assessed system of water quality indices. The emergent properties of the ecosystem predicted from the model simulations were also compared with lake data as a form of indirect validation of the model. Model output, in good agreement with lake data, indicated differential effects of nitrogen and phosphorus nutrient loading on concentrations, and major in-lake fluxes, of TN and TP, and dynamics and algal community structure. Both model output and lake data indicated a strong relationship between nitrogen loading and in-lake TN values. This relationship is not apparent for phosphorus and only a weak relationship exists between phosphorus loading and in-lake TP. The modeling results, expressed in terms of water quality, allowed establishment of critical/threshold values for the nutrient loads. Implementation of the ecological modeling supplemented with the quantified set of WQ indices allowed us to take a step towards establishment of the association between permissible ranges for water quality and major management measures, i.e. towards sustainable management. 相似文献
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Transnational corporations (TNCs) invest enormous resources in their corporate social responsibility (CSR) programmes in the Niger Delta region of Nigeria. However, the effectiveness and mode of execution of these CSR activities have been subjects of continuing debate. This research was therefore carried out to elicit the perspectives of members of four local communities about the impact of the CSR interventions in the areas of health improvement and participation by members of the communities in the Niger Delta. Semi-structured questionnaires were self-completed by 182 members of the local communities in the Niger Delta; the respondents gave detailed feedback about community feelings for TNCs and their CSR efforts. The findings showed that the people generally have negative views towards the CSR practices of the TNCs. The result of a two-paired t-test showed this to be true for both men and women (P =?.888, CI 95). While 69.8% of the respondents felt that the TNCs did not bring any development to their community, 87.9% had high fear of getting a disease due to the community they live in; interestingly, 90.1% wanted to be involved in decisions concerning their communities. This research therefore proposes the increased use of health impact assessment as an approach to integrate health considerations and community participation into the evaluation and implementation of development programmes in the Niger Delta. Such an approach has the potential to make CSR initiatives more effective, transparent, and minimise the tensions between communities and TNCs. 相似文献
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