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51.
Environmental Science and Pollution Research - Large-scale wastewater schemes rely on multi-barrier approach for the production of safe and sustainable recycled water. In multi-barrier wastewater...  相似文献   
52.
Growth of cells from amniotic fluid was studied with respect to cell concentration in the inoculum, blood contamination of the fluid, fluid colour, fluid clarity, gestational age of the pregnancy, and growth factors. Dependent variables measured were colony formation, colony size, and colony morphology after 7, 11, and 14 days of culture. The following conclusions were established from these studies: small sample volumes are the most efficient for producing colonies; cells from very bloody or dark brown fluids have a slower rate of growth; growth of cells from cloudy (noncontaminated) fluids is better than growth of cells from clear fluids; the proportion of colonies that are epithelioid varies with gestational age; the stimulating effect of 100 ng/ml fibroblast growth factor on cells from amniotic fluid was confirmed.  相似文献   
53.
Climate Change and River Ecosystems: Protection and Adaptation Options   总被引:3,自引:0,他引:3  
Rivers provide a special suite of goods and services valued highly by the public that are inextricably linked to their flow dynamics and the interaction of flow with the landscape. Yet most rivers are within watersheds that are stressed to some extent by human activities including development, dams, or extractive uses. Climate change will add to and magnify risks that are already present through its potential to alter rainfall, temperature, runoff patterns, and to disrupt biological communities and sever ecological linkages. We provide an overview of the predicted impacts based on published studies to date, discuss both reactive and proactive management responses, and outline six categories of management actions that will contribute substantially to the protection of valuable river assets. To be effective, management must be place-based focusing on local watershed scales that are most relevant to management scales. The first priority should be enhancing environmental monitoring of changes and river responses coupled with the development of local scenario-building exercises that take land use and water use into account. Protection of a greater number of rivers and riparian corridors is essential, as is conjunctive groundwater/surface water management. This will require collaborations among multiple partners in the respective river basins and wise land use planning to minimize additional development in watersheds with valued rivers. Ensuring environmental flows by purchasing or leasing water rights and/or altering reservoir release patterns will be needed for many rivers. Implementing restoration projects proactively can be used to protect existing resources so that expensive reactive restoration to repair damage associated with a changing climate is minimized. Special attention should be given to diversifying and replicating habitats of special importance and to monitoring populations at high risk or of special value so that management interventions can occur if the risks to habitats or species increase significantly over time.  相似文献   
54.
Abstract: A decision support system for sustainable water resources management in a water conflict resolution framework is developed to identify and evaluate a range of acceptable alternatives for the Geum River Basin in Korea and to facilitate strategies that will result in sustainable water resource management. Working with stakeholders in a “shared vision modeling” framework, sustainable management strategies are created to illustrate system tradeoffs as well as long‐term system planning. A multi‐criterion decision‐making (MCDM) approach using subjective scales is utilized to evaluate the complex water resource allocation and management tradeoffs between stakeholders and system objectives. The procedures used in this study include the development of a “shared vision model,” a simulated decision‐making support system (as a tool for sustainable water management strategies associated with water conflicts, management options, and planning criteria), and the application of MCDM techniques for evaluating alternatives provided by the model. The research results demonstrate the utility of the sustainable water resource management model in aid of MCDM techniques in facilitating flexibility during initial stages of alternative identification and evaluation in a basin suffering from severe water conflicts.  相似文献   
55.
经过近4年时间的准备之后,非洲即将开始一个创新的举措.非洲库存计划(ASP)是一个涉及非洲国家、国际机构、非政府组织、私营部门CropLife国际(CLI)和区域性团体的多风险承担者伙伴关系.非洲库存计划的目标是雄心勃勃的:在下一个10年到15年清理和处理整个非洲现有的库存农药,并帮助防止未来的农药积累,总成本约为2.5-3.0亿美元.幸亏有全球环境机构(GEF)的2500万美元的基本支持以及捐献国政府的共筹资金,在15个国家的第一阶段活动资金已经增加到5000多万美元.然而第一阶段的工作和第二阶段计划仍然需要另外的2000万美元资金.  相似文献   
56.
Internet-based research is increasingly important for conservation science and has wide-ranging applications and contexts, including culturomics, illegal wildlife trade, and citizen science. However, online research methods pose a range of ethical and legal challenges. Online data may be protected by copyright, database rights, or contract law. Privacy rights may also restrict the use and access of data, as well as ethical requirements from institutions. Online data have real-world meaning, and the ethical treatment of individuals and communities must not be marginalized when conducting internet-based research. As ethics frameworks originally developed for biomedical applications are inadequate for these methods, we propose that research activities involving the analysis of preexisting online data be treated analogous to offline social science methods, in particular, nondeceptive covert observation. By treating internet users and their data with respect and due consideration, conservationists can uphold the public trust needed to effectively address real-world issues.  相似文献   
57.
58.
The national Forest Health Monitoring (FHM) program requires protocols for monitoring soil carbon contents. In a pilot study, 30 FHM plots loblolly shortleaf (Pinus taeda L./Pinus echinata Mill.) pine forests across Georgia were sampled by horizon and by depth increments. For total soil carbon, approximately 40% of the variance was between plots, 40% between subplots and 20% within subplots. Results by depth differed from those obtained by horizon primarily due to the rapid changes in carbon content from the top to the bottom of the A horizon. Published soil survey information overestimated bulk densities for these forest sites. The measurement of forest floor depths as a substitute to sampling did not provide reliable estimates of forest floor carbon. Precision of replicate samples was approximately 10-30% for field duplicates and 5-10% for laboratory duplicates. Based on national indicator evaluation criteria, sampling by depth using bulk density core samplers has been recommended for national implementation. Additional procedures are needed when sampling organic soils or soils with a high percentage of large rock fragments.  相似文献   
59.
The importance of information technology to the world economy has brought about a surge in demand for electronic equipment. With rapid technological change, a growing fraction of the increasing stock of many types of electronics becomes obsolete each year. We model the costs and benefits of policies to manage 'e-waste' by focusing on a large component of the electronic waste stream-computer monitors-and the environmental concerns associated with disposal of the lead embodied in cathode ray tubes (CRTs) used in most monitors. We find that the benefits of avoiding health effects associated with CRT disposal appear far outweighed by the costs for a wide range of policies. For the stock of monitors disposed of in the United States in 1998, we find that policies restricting or banning some popular disposal options would increase disposal costs from about US dollar 1 per monitor to between US dollars 3 and US dollars 20 per monitor. Policies to promote a modest amount of recycling of monitor parts, including lead, can be less expensive. In all cases, however, the costs of the policies exceed the value of the avoided health effects of CRT disposal.  相似文献   
60.
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