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761.
赵历男 《中国人口.资源与环境》2003,13(2):88-91
本文在分析我国城市可持续发展对智能运输系统管理规划的需求的基础上,指出了我国城市交通存在的问题,并根据我国城市的特点,提出了制定城市智能运输系统管理规划的原则和注意事项,并对城市智能运输系统管理规划的总体结构和总体配置,以及实施步骤提出了设想。 相似文献
762.
化肥行业噪声危害调查及治理评价 总被引:1,自引:0,他引:1
通过对7家大中型化肥厂的噪声调查,分析了化肥行业中的噪声源特性和岗位噪声暴露状况。对1601名作业工人进行了体检并得出了噪声危害和岗位噪声的剂量──反应关系。还对各厂已采取的噪声治理措施进行了技术评价。最后,根据化肥行业的特点,提出了降低噪声和加强听力保护的几点建议。 相似文献
763.
本次吊扇电机温升水平测试活动采用平行样品试验方案,尽管通过了严格的样品定制、测试和筛选以控制样品离散性,但所收集到的水平测试数据经过稳健统计法和Z值评估法的分析后发现平行样品的离散性对水平测试结果的影响不可忽略,导致所给出的评价结果是具有较大的风险性和不公平性。这意味着该次水平测试活动采用平行样品试验方案一种错误的选择。 相似文献
764.
Hallett J. Harris Paul E. Sager Sumner Richman Victoria A. Harris C. Jarrell Yarbrough 《Environmental management》1987,11(5):619-625
Continued resource degradation in various areas of the Great Lakes has led to doubts of the adequacy of conventional science and management approaches. The need for a more holistic approach, identified as an ecosystem approach, appears now to be more widely accepted although progress with implementation is slow. We argue here that ecosystem science is an integral part of an ecosystem approach and is a prerequisite to effective management planning.One of the problems of implementing an ecosystem approach is forging the link between ecosystem based research and management. For Green Bay, Wisconsin, USA, certain structural and functional qualities of the ecosystem have been used to define operational guides and to formulate management objectives. These objectives are being utilized in the development of a remedial action plan for Green Bay.Deceased 5 February 1986. 相似文献
765.
Daniel H. Hoggan 《Journal of the American Water Resources Association》1972,8(3):625-630
ABSTRACT As availability of funds in the federal budget for water development has decreased recently, pressure has increased for state and local governments to pay a larger share of the costs. In this situation a difficult question immediately arises-what is the capability of state and local governments to pay a larger share? Of course, there is no easy answer. Expenditures of public funds are policy outcomes of a government's political process in which political, economic, legal and other factors are involved in complex relationships. The traditional sources of capital funds for state and local governments include bond proceeds, tax revenues, and federal financial aid (state aid is also a major source of local government funds). The issuing of bonds is hampered by a variety of legal debt limitations, but there are means for circumventing the limitations. State and local governments vary widely in amounts of taxable resources available and in the extent to which these resources have been tapped. More effective use of revenue resources could be made in some cases. New sources of capital funds for water development ought to be considered-a fee on the use of water per se, for example. Costs associated with water use currently are imposed to cover development costs, but a state might impose additional use fees earmarked for a state water development fund. 相似文献
766.
Raymond Herrmann 《Journal of the American Water Resources Association》1997,33(4):747-753
ABSTRACT: Integrated watershed ecosystem studies in National Parks or equivalent reserves suggest that effects of external processes on “protected” resources are subtle, chronic, and long-term. Ten years of data from National Park watersheds suggests that temperature and precipitation changes are linked to nitrogen levels in lakes and streams. We envision measurable biotic effects in these remote watersheds, if expected climate trends continue. The condition of natural resources within areas set aside for preservation are difficult to ascertain, but gaining this knowledge is the key to understanding ecosystem change and of processes operating among biotic and abiotic ecosystem components. There is increasing evidence that understanding the magnitude of variation within and between such processes can provide an early indication of environmental change and trends attributable to human-induced stress. The following four papers are case studies of how this concept has been implemented.* These long-term studies have expanded our knowledge of ecosystem response to natural and human-induced stress. The existence of these sites with a commitment to gathering “long-term” ecosystem-level data permits research activities aimed at testing more important hypotheses on ecosystem processes and structure. 相似文献
767.
Lee TM 《Environmental monitoring and assessment》2005,111(1-3):307-323
This study analyzes the results of the first 5 years of long-term environmental monitoring of the dynamics of coastal vegetation
communities in southwestern Taiwan. Seven permanent plots were established in major vegetation communities, including grassland,
windbreak forest, and secondary succession forest. Results showed that species richness decreased yearly in grasslands but
fluctuated moderately in the forest plots. A Jaccard similarity coefficient was used to evaluate the similarities of species
composition between different monitoring years. Species composition changed rapidly in grassland sites, with the similarity
coefficient dropping from 82 to 29% in 5 years. The similarity coefficient of vegetation in the compositehardwood forest dropped
from 80 to 50%, indicating that at least half the species were the same as those in the beginning and that the composition
of forest communities was more stable than that of grassland communities. Dominant species in the forest community changed
gradually during the monitoring period. The original planting of Casuarina equisetifolia in windbreak forests decreased year by year in most of the plots, while Cerbera manghas and Ficus microcarpa became the dominant species. The trend of replacement of dominant species indicates that most of the vegetation communities
are still in successional stages. 相似文献
768.
Thimonier A Schmitt M Waldner P Rihm B 《Environmental monitoring and assessment》2005,104(1-3):81-118
Atmospheric deposition of the major elements was estimated from throughfall and bulk deposition measurements on 13 plots of the Swiss Long-Term Forest Ecosystem Research (LWF) between 1995 and 2001. Independent estimates of the wet and dry deposition of nitrogen (N) and sulfur (S) on these same plots were gained from combined simplified models. The highest deposition fluxes were measured at Novaggio (Southern Switzerland), exposed to heavy air pollution originating from the Po Plain, with throughfall fluxes averaging 29 kg ha–1 a–1 for N and 15 kg ha–1 a–1 for S. Low deposition fluxes were measured on the plots above 1800 m, with throughfall fluxes lower than 4.5 kg ha–1 a–1 for N and lower than 3 kg ha–1 a–1 for S. The wet deposition of N and S derived from bulk deposition was close to the modeled wet deposition, but the dry deposition derived from throughfall was significantly lower than the modeled dry deposition for both compounds. However, both the throughfall method and the model yielded total deposition estimates of N which exceeded the critical loads calculated on the basis of long-term mass balance considerations. These estimates were within or above the range of empirical critical loads except above 1800 m. 相似文献
769.
J. D. Bień J. ter Meer W. H. Rulkens H. H. M. Rijnaarts 《Environmental Modeling and Assessment》2005,9(4):221-226
A Health Index/Risk Evaluation Tool (HIRET) has been developed for the integration of risk assessment and spatial planning using GIS capabilities. The method is meant to assist decision makers and site owners in the evaluation of potential human health risk with respect to land use. Human health risk defined as the potential adverse effects on human life or health is generally accepted as the most important aspect for site assessment and planning of remediation strategies. It concerns polluted sites that endanger human health on one hand and derelict land that does not cause the immediate risk on the other hand. In current state-of-the-art risk-assessment, long-term spatial and temporal changes of risks, in relation to changes in contamination patterns and land use functions, are not taken into account. The aim of this paper is to demonstrate the methodology developed for human health risk assessment in aspect of spatial and temporal domain. HIRET was developed as an extension for ESRI software ArcView 3.2 and allows performing dynamic human health risk assessment in long-term period, which is relevant for land use planning. The paper illustrates how such methodology can assist in environmental decision-making to enhance the efficiency of contaminated land management. A case study of contaminated site is given showing how data can be used within a GIS framework to produce maps indicating areas of potential human health risk. 相似文献
770.
Kļaviņ M Rodinov V Kokorite I Kļaviņa I Apsite E 《Environmental monitoring and assessment》2001,66(3):233-251
The changes of the chemical composition in Latvianinland waters over the last twenty years weredetermined, based on data of the National MonitoringProgramme. Relationships between the water compositionwere studied. The chemical composition and seasonalchange pattern depend a lot on hydrological factorswhich differed between eastern and western Latvia.Different pattern of long-term changes is found forsubstances which have different sources andsinks, at first for nutrients (decrease only in the lastfew years) and inorganic ingredients (commonlyincreasing trend). An attempt was made to identify themain sources of the major water ingredients and linkchanges of their concentrations with changes inloading to waters. 相似文献