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101.
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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Abstract:  Conservation efforts are only as sustainable as the social and political context within which they take place. The weakening or collapse of sociopolitical frameworks during wartime can lead to habitat destruction and the erosion of conservation policies, but in some cases, may also confer ecological benefits through altered settlement patterns and reduced resource exploitation. Over 90% of the major armed conflicts between 1950 and 2000 occurred within countries containing biodiversity hotspots, and more than 80% took place directly within hotspot areas. Less than one-third of the 34 recognized hotspots escaped significant conflict during this period, and most suffered repeated episodes of violence. This pattern was remarkably consistent over these 5 decades. Evidence from the war-torn Eastern Afromontane hotspot suggests that biodiversity conservation is improved when international nongovernmental organizations support local protected area staff and remain engaged throughout the conflict. With biodiversity hotspots concentrated in politically volatile regions, the conservation community must maintain continuous involvement during periods of war, and biodiversity conservation should be incorporated into military, reconstruction, and humanitarian programs in the world's conflict zones.  相似文献   
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The UNEP International Register of Potentially Toxic Chemicals (IRPTC) was created by the UN Conference on the Human Environment of 1972. Its influence and co-operation in the 80ies with other international programmes of the WHO, FAO, OECD, and EC for the control of chemicals is presented here. The follow-up of the UN Conference on the Environment and Development (1992) created three new bodies that are to implement chapter 19 of Agenda 21 (Environmentally Sound Management of Chemicals): The UN Commission of Sustainable Development, the International Forum on Chemical Safety, and the Interorganisation Programme for the Sound Management of Chemicals. This UN Conference also brought about a new orientation ofIIRPTC. In 1996, IRPTC was renamed as UNEP Chemicals and has been functioning in three major fields since then: The international convention on Prior Informed Consent, the international convention on the control of Persistent Organic Pollutants and, finally, a continuation of is traditional field of information exchange on chemicals.  相似文献   
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猪粪堆肥中一株溶磷菌的筛选鉴定及溶磷能力初步测定   总被引:2,自引:0,他引:2  
从猪粪堆肥中分离纯化得到一株具有较强溶磷能力的菌株PSM-1,进行了形态学和分子生物学鉴定,研究了其溶磷能力和遗传稳定性.结果表明:通过菌落形态和ITS基因序列分析鉴定,菌株PSM-1为产黄青霉(Penicillium chrysogenum);在3种不同无机磷源液体培养基中其溶磷量依次为Ca3(PO4)2(138.36 mg·L-1)Fe PO4(117.38 mg·L-1)Al PO4(113.76 mg·L-1),且PSM-1的溶磷量均与培养液p H值呈现出显著负相关性;以葡萄糖为碳源、硝酸铵为氮源时,菌株PSM-1的溶磷量最高可达195.67 mg·L-1,比初始有效磷高141.42%;该菌株对碳源和氮源的利用效率分别依次为:葡糖糖蔗糖麦芽糖淀粉,硝酸铵硝酸钾硫酸铵草酸铵;经过20次传代培养后PSM-1的溶磷量保持在(124.54±3.50)mg·L-1,说明其溶磷遗传稳定性良好.研究表明:PSM-1菌株具有良好的溶解无机磷的能力,在土壤微生态改良方面具有重要的应用潜力.  相似文献   
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ABSTRACT: Public involvement in water resources planning is receiving much current attention, and there is a need to examine systematically how different public involvement techniques work in practice. The following techniques were among those used to involve the public in a recent Corps of Engineers’study of flooding on San Pedro Creek in Pacifica, California: a public workshop, citizen information bulletins (CIBs) and questionnaries. Interviews were held with 75 study participants to evaluate the effectiveness of these techniques. The interviews indicated that various study participants felt positively about the particular workshop format employed and about the use of a communications specialist to train workshop leaders. There were mixed reactions to the effectiveness of the CIBs and questionnaires. Although many individual citizens felt that the CIBs and questionnaires were useful, some of the Corps planners felt that CIBs and questionnaires would only be “cost-effective” on large studies and/or where the questionnaire response rate was high. The interviews led to a number of specific suggestions regarding how the extent of public involvement could be increased in future water resources planning studies.  相似文献   
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