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691.
/ The Galilee region on the northern edge of Israel constitutes more than 15% of the state's territory, supplies more than half of its drinking water needs, and is an important recreational resource and destination for Israelis. One of the main objectives of the plan for the Galilee was to devise a regional physical and economic development strategy for the years 1992-2007 that would arrest the trend of emigration of its residents, attract newly arrived immigrants to the region, and at the same time protect natural resources and environmental quality. This paper is limited to discussion of the environmental aspects of the plan. It analyzes spatial concepts for distribution of projected population growth, evaluates environmental impacts of alternative plans, and proposes a decision-making framework and tools for minimizing natural resources loss from development at the local level. Assessment of potential environmental impacts generated quantitative data of natural resources areas. Application of the data in the plan evaluation stage showed that the alternative that concentrated most of the new development in central Galilee was the second-best choice environmentally, but was preferred as the best choice for overall qualities. The planning study offers an alternative environmental impact assessment (EIA) process to the one presently used in Israel by incorporating environmental considerations at the initial plan-making stage and not at the plan-approval stage. It demonstrated that in order to be effective, environmental assessment and land-use planning should be seen as one effort that is integrated from the start and in each stage of the plan-making process.KEY WORDS: Environmental assessment; Development planning; Galilee  相似文献   
692.
Voluntary environmental reporting on the progress achieved against policy objectives is an emerging trend in industry and business and is recognized as a valuable aid in implementing policy and improving environmental management systems. Environmental reporting in the UK, has a whole range of formats including PERI, GEMI, WICE and EMAS, with the last, in particular, aiming to improve the level of environmental stewardship and to increase the flow of environmental information to audiences both internally and externally. Higher education institutions globally have been slow to respond in this respect and there is much that they can learn from corporate environmental reporting. An environmental policy is not sufficient proof of commitment for those institutions who have signed the global Talloires Declaration or the European COPERNICUS Charter: demonstrable progress in policy implementation is essential. The environmental management systems that higher education institutions adopt or create and the ways in which their environmental information is collated are of great significance, but the medium selected for the report is perhaps one of the most important aspects to consider. Those institutions such as the University of Sunderland, UK who are using the World Wide Web have been able to produce a flexible, hypertext-linked service on request with inbuilt feedback mechanisms containing varied, up-to-date, comprehensive and well-structured environmental information signposted to external pro-active institutions and agencies. These reports have unique educational angles and reveal links and networks that are naturally more pervasive and far-reaching in their scope and impact and could well provide a key way forward to practical and sustainable environmental reporting into the millennium.  相似文献   
693.
ABSTRACT: Many users of hydrometeorological records are not aware of the number of inconsistencies and biases that occur in hydrometeorological records. Examples are presented illustrating how the exposures of sites for measurement of precipitation, wind, snow on the ground, and evaporation determine to a large extent how useful the records are for estimating areal conditions. For areas where precipitation in the form of snow produces a significant portion of the runoff, a smaller number of quality records may be more valuable for modeling than a much larger number of records of lower quality. Information is presented to show that the overall value of an operational hydrometeorological network is dependent upon how consistent and representative of average conditions the collected records are, especially for mountainous areas in cold regions.  相似文献   
694.
Until now no structured methodology existed for attuning environmental considerations to the business strategy of companies. The Environmental Competence Centre of Philips Sound & Vision in The Netherlands has developed and tested a methodology for this purpose. This methodology, called Selection of STRrategic Environmen Tal CHallenges (STRETCH), has proven to lead to promising results and should therefore be actively promoted. In this article, the authors show how the application of STRETCH provides the possibility of meeting three main objectives: First, focusing on the incorporation of environmental aspects into the company's business strategy can elicit innovations that may enhance the competitive position of the company by cost reduction and/or higher market shares. Second, the environmental opportunities and threats to be expected in the future can be anticipated in an earlier phase. Through this proactive approach a company can avoid external criticism and take the lead in environmental priority setting. Third, by applying the STRETCH methodology even higher eco-efficiencies are expected to be reached than through incremental, step-by-step environmental improvements.  相似文献   
695.
ABSTRACT: Natural rates of surface erosion on forested granitic soils in central Idaho were measured in 40 m2 bordered erosion plots over a period of four years. In addition, we measured a variety of site variables, soil properties, and summer rainstorm intensities in order to relate erosion rates to site attributes. Median winter erosion rates are approximately twice summer period rates, however mean summer rates are nearly twice winter rates because of infrequent high erosion caused by summer rainstorms. Regression equation models and regression tree models were constructed to explore relationships between erosion and factors that control erosion rates. Ground cover is the single factor that has the greatest influence on erosion rates during both summer and winter periods. Rainstorm intensity (erosivity index) strongly influences summer erosion rates, even on soils with high ground cover percentages. Few summer storms were of sufficient duration and intensity to cause rilling on the plots, and the data set was too small to elucidate differences in rill vs. interrill erosion. The regression tree models are relatively less biased than the regression equations developed, and explained 70 and 84 percent of the variability in summer and winter erosion rates, respectively.  相似文献   
696.
In-situ sparging has been accepted as a method to rapidly remediate groundwater at considerably lower costs compared to remedies based on groundwater recovery alone. The success of in-situ sparging depends on effective mass transfer between air and contaminated media in the subsurface. Factors affecting mass transfer include advective airflow, diffusive transport, interphase chemical partitioning, and chemical and biological reaction rates between sparged gases and subsurface contaminants, minerals, and naturally occurring organic compounds. Understanding these factors can increase the design efficiency of in-situ sparging and assist in developing sparging systems that use gases other than air (i.e., oxygen, ozone, and methane).  相似文献   
697.
A pedagogic problem in forestry and landscape management is to visualize future landscape effects of forest growth and current management activities in the forest. This paper presents a method for forecasting digital image projections of forest landscape dynamics. Static nonlinear regression functions estimate the digital numbers in a Landsat Thematic Mapper image. Regressors used are forest stand variables. By estimating the future forest stand data, based on intermediate treatment and growth, future satellite digital images are created. In a case study example, the future landscape of a forest block in the province of Västernorrland, Sweden, is projected to demonstrate the application of this visualization technique.  相似文献   
698.
This project investigated the feasibility of using sewage sludge to culture microalgae (Chlorella-HKBU) and their subsequent usage as feeds for rearing different organisms. Part II of the project evaluated the results of applying the sludge-grown algae to feedOreochromis mossambicus (fish),Macrobrachium hainenese (shrimp), andMoina macrocopa (cladocera). In general, the yields of the cultivated organisms were unsatisfactory when they were fed the sludge-grown algae directly. The body weights ofO. mossambicus andM. macrocopa dropped 21% and 37%, respectively, although there was a slight increase (4.4%) inM. hainenese. However, when feeding the algal-fed cladocerans to fish and shrimp, the body weights of the fish and shrimp were increased 7% and 11% accordingly. Protein contents of the cultivated organisms were comparable to the control diet, although they contained a rather high amount of heavy metals. When comparing absolute heavy metal contents in the cultivated organisms, the following order was observed: alga > cladocera > shrimp, fish > sludge extracts. Bioelimination of heavy metals may account for the decreasing heavy metal concentrations in higher trophic organisms.  相似文献   
699.
Summary Quantitative studies on the biomethanation processes using a different biomass (goat dung, cow dung, buffalo dung, piggery waste, poultry waste and sewage) alone or in combination have been made. The dung samples have been found to be an efficient producer of biogas at a 1:2 dilution. Better yields of biogas are obtained in combination with other biomasses rather than when used alone. Judicious mixing of biomasses, however, is important. Competitive biomethanation of a biomass by other biomasses as a source for a wild population of microbes has been studied in vials using a cross-inoculation technique, i.e. using inoculum of one biomass on different sterile biomasses. The results show that the microbes are very specific and usually non-adaptive. Each inoculum outclasses others in using its natural biomass for methanation but reacts poorly when inoculated to other alien biomasses. Buffalo dung is to some extent adaptive in nature.Professor S.C. Lahiri is the senior author of this paper and he is ex-Head of the Department of Chemistry at the University of Kalyani where Nilanjan Chakravorty is a research fellow. Dr G.M. Sarkar is a senior lecturer in the Department of Botany at Ranaghat College, Ranaghat, Nadia, West Bengal, India.  相似文献   
700.
Numerous studies have evaluated air quality and greenhouse gas mitigation benefits of biomass energy systems, but the potential environmental impacts associated with large-scale changes in land-use patterns needed to produce energy crops have not been quantified. This paper presents a framework to assess the potential soil, water, and biodiversity impacts that may result from the large-scale production of dedicated energy crops. The framework incorporates producer economic decision models with environmental models to assess changes in land use patterns and to quantify the consequent environmental impacts. Economic and policy issues that will affect decisions to produce energy crops are discussed. The framework is used to evaluate erosion and chemical runoff in two Tennessee regions. The analysis shows that production of dedicated energy crops in place of conventional crops will significantly reduce erosion and chemical runoff.  相似文献   
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