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991.
Water quality monitoring using remote sensing has been studied in Finland for many years. But there are still few discussions on water quality monitoring using remote sensing technology in support of water policy and legislation in Finland under the WFD. In this study, we present water quality monitoring using remote sensing in the Gulf of Finland, and focus on the spatial distribution of water quality information from satellite-based observations in support of water policy by a case study of nitrate concentrations in surface waters. In addition, we briefly describe instruments using a system of river basin districts (RBD), highlighting the importance of integrated water resources and river-basin management in the WFD, and discuss the role of water quality monitoring using remote sensing in the implementation of water policy in Finland under the WFD.  相似文献   
992.
循环经济是以科学发展观为统领,以先进的科学技术为基础,以低消耗、低排放、高效率为特征的集约化、内涵式经济增长模式。为了促使我国走上循环经济发展之路,就必须建立循环经济科技支撑体系,即以政府为主导、企业为主体、社会化服务机构健全的循环经济科技创新体系和完善的循环经济科技政策体系、法律法规体系以及绿色文化与教育体系。  相似文献   
993.
Abstract: Water demand in a viable economy tends to be dynamic: it changes over time in response to growth, drought, and social policy. Institutional capacity to re‐allocate water between users and uses under stress from multiple sources is a key concern. Climate change threatens to add to those stresses in snowmelt systems by changing the timing of runoff and possibly increasing the severity and duration of drought. This article examines Snake and Klamath River institutions for their ability to resolve conflict induced by demand growth, drought, and environmental constraints on water use. The study finds that private ownership of water rights has been a major positive factor in successful adaptation, by providing the basis for water marketing and by promoting the use of negotiation and markets rather than politics to resolve water conflict.  相似文献   
994.
Abstract: As nearly all of Texas’ rural lands are privately owned, landowner associations for the management of white‐tailed deer and ground‐water have become increasingly popular. Deer are a common‐pool resource with transboundary characteristics, requiring landowner cooperation for effective management. Ground‐water reserves are economically important to landowners, but are governed by the “rule of capture” whereby property rights are not defined. One ground‐water association and four wildlife management associations (WMAs) were surveyed to characterize their member demographics, land use priorities, attitudes, and social capital. Members of the ground‐water cooperative were part of a much larger, more heterogeneous, and more recently formed group than members of WMAs. They also placed greater importance on utilitarian aspects of their properties, as opposed to land stewardship for conservation as practiced by members of WMAs. If ground‐water association members could be more locally organized with more frequent meetings, social capital and information sharing may be enhanced and lead to land stewardship practices for improved hydrologic functions and sustained ground‐water supply. This, coupled with pumping rules assigned by the local ground‐water district, could yield an effective strategy that is ecologically and hydrologicaly sound, and that allows rural provision of water supply to urban consumers.  相似文献   
995.
Abstract: Dissolved silica (DSi) availability is a factor that affects the composition of algal populations in aquatic ecosystems. DSi cycling is tightly linked to the hydrological cycle, which is affected by human alterations of the landscape. Development activities that increase impervious cover change watershed hydrology and may increase the discharge of DSi‐poor rainwater and decrease the discharge of DSi‐rich ground water into aquatic ecosystems, possibly shifting algal community composition toward less desirable assemblages. In this study, DSi loadings from two adjacent coastal watersheds with different percent impervious cover were compared during four rain and five nonrain events. Loadings in the more impervious watershed contained a significantly larger proportion of surface runoff than base flow (ground‐water discharge) and had lower [DSi] water during rain events than the less impervious watershed. Application of the Soil Conservation Service Curve Number (CN) method showed that the minimum rainfall height necessary to yield runoff was significantly lower for the more impervious watershed, implying that runoff volumes increase with impervious cover as well as the frequency of runoff‐yielding events. Empirical data collected during this study and estimates derived from the CN method suggest that impervious cover may be responsible for both short‐term DSi limitation during rain events as well as long‐term reduction of DSi inputs into aquatic ecosystems.  相似文献   
996.
Abstract: Spatio‐temporal linkages between hydrologic and ecologic dimensions of watersheds play a critical role in conservation policies. Habitat potential is influenced by variation along longitudinal and lateral gradients and land use disturbance. An assessment of these influences provides critical information for protecting watershed ecosystems and in making spatially explicit, conservation decisions. We use an ecohydrologic approach that focuses on interface between hydrological and ecological processes. This study focuses on changes in watershed habitat potentials along lateral (riparian), and longitudinal (stream order) dimensions and disturbance (land use). The habitat potentials were evaluated for amphibians, reptiles, mammals, and birds in the Westfield River Watershed of Massachusetts using geographic information systems and multivariate analysis. We use a polynomial model to study nonlinear effects using robust regression. Various spatial policies were modeled and evaluated for influence on species diversity. All habitat potentials showed a strong influence along spatial dimensions and disturbance. The habitat potential for all vertebrate groups studied decreased as the distance from the riparian zone increased. Headwaters and lower order subwatersheds had higher levels of species diversity compared to higher order subwatersheds. It was observed that locations with the least disturbance also had higher habitat potential. The study identifies three policy criteria that could be used to identify critical areas within a watershed to conserve habitat suitable for various species through management and restoration activities. A spatially variable policy that is based on stream order, riparian distance, and land use can be used to maximize watershed ecological benefits. Wider riparian zones with variable widths, protection of headwaters and lower order subwatersheds, and minimizing disturbance in riparian and headwater areas can be used in watershed policy. These management objectives could be achieved using targeted economic incentives, best management practices, zoning laws, and educational programs using a watershed perspective.  相似文献   
997.
The regulatory structures underlying United States and European Union policies regarding genetically modified (GM) food and crops are fundamentally different. The US regulates GM foods and crops as end products, applying roughly the same regulatory framework that it does to non GM foods or crops. The EU, on the other hand, regulates products of agricultural biotechnology as the result of a specific production process. Accordingly, it has developed a network of rules that regulate GM foods and crops specifically. As a result, US regulation of GM foods and crops is relatively permissive, whereas EU regulation is relatively restrictive. Why are genetically modified food policies in the United States and the European Union so strikingly different? In the light of the recent World Trade Organization dispute on agricultural biotechnology, it may seem that economic interests are the driving force behind policies. While they are certainly part of the picture, the issue is far more complex. This paper argues that three different elements help explain differences between US and EU GM food policies. First, an investigation of US and European policies of the 1970s and 1980s on recombinant DNA research and of events leading up to early GM food and crop regulation allows a deeper understanding of current policy. Second, scrutinizing underlying values and norms can uncover the beliefs that condition current GM food and crop policy. Third, an analysis of involved actors’ views and levels of success in influencing policy is essential to understanding US and EU policies.  相似文献   
998.
The traditional vision of the role science should play in policy making is of a two stage process of scientists first finding out the facts, and then policy makers making a decision about what to do about them. We argue that this two stage process is a fiction and that a distinction must be drawn between pure science and science in the service of public policy. When science is transferred into the policy realm, its claims to truth get undermined because we must abandon the open-ended nature of scientific inquiry. When we move from the sphere of science to the sphere of policy, we pick an arbitrary point in the open-ended scientific process, and ask our experts to give us the answer. The choice of the endpoint, however, must always be arbitrary and determined by non-scientific factors. Thus, the two stages in the model of first finding the facts, and then making a decision about what to do, cannot be clearly separated. The second stage clearly affects the first. This conclusion will have implications about existing scientific policy institutions. For example, we advocate that the environmental assessment process be radically overhauled, or perhaps even let go. It will be our position that ultimately a better model for the involvement of scientists in public policy debates is that of being participants in particular interest groups (“hired guns”), rather than as supposedly unbiased consultants to decision-makers.  相似文献   
999.
电解铝生产环境负荷分析和预测模型研究   总被引:1,自引:0,他引:1  
利用生命周期评价的分析方法,对铝电解生产过程中资源消耗、能源消耗和污染物排放进行了分析,采用等效环境指数计算了铝电解生产过程中的环境负荷,并分析了各因素对环境负荷的影响,其中氟化盐的投入量对环境负荷影响较大.运用神经网络对铝电解生产过程的环境负荷进行预测,在负荷预测过程中,首先对样本数据进行归一化处理,然后采用BP算法对神经网络进行训练.最后用训练好的网络进行预测,将预测结果与实际数据进行比较,证明具有较好的预测效果.  相似文献   
1000.
全过程固体废物管理研究进展及其对我国相关管理的启示   总被引:3,自引:0,他引:3  
当某种固态、半固态物质不再具有原有的价值,它就成了固体废物,并可能在产生、排放、收集、贮存、运输、利用、处理和处置过程的任何一个或多个环节产生对环境的污染危害。对固体废物进行全过程监督管理因而显得尤为重要。本文回顾了全过程固体废物管理实施方法,包括生命周期清单和生命周期评价方法,用于废物管理系统的模型,在固体废物产生量预测、收集系统最优化以及处理处置设施选址等步骤中,各自所用不同方法的进展,以及在一些较发达国家和地区的管理实例。最后讨论了这些进展对我国固体废物相关管理的启示。  相似文献   
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