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991.
Safei El-Deen Hamed 《Journal of Agricultural and Environmental Ethics》1993,6(2):145-164
A comprehensive paradigm of environmental ethics should encompass two things: (1) a particular way of life, and (2) a path to achieve that ideal. An effective paradigm must also be internally consistent, yet externally workable in the real world. On the whole, the modern environmental movement has failed to provide these essential components and qualities in its associated philosophies, most of which suffer from being too abstract or too utopian.This paper suggests that Islam, as a religion and as a body of knowledge, is capable of providing its followers with a comprehensive and practical system of environmental ethics. The basic principles and guidelines of the faith represent the conceptual ideal, while Islamic institutions and laws provide the operational components of an ethical system. 相似文献
992.
Lee H. MacDonald 《Journal of the American Water Resources Association》1993,29(3):357-368
ABSTRACT: Recent assessments have emphasized the lack of a field and laboratory component in hydrologic education at the university level. Consequences of this lack include: (1) an unwarranted faith in published data; (2) lack of appreciation for the spatial and temporal variability of most hydrologic processes; (3) lack of appreciation for the difficulty of collecting good quality field data; (4) an inability to design and execute projects to collect field data; (5) a lack of field experience which can be applied when confronted with different problems or new environments; (6) an inability to evaluate published materials or models against “field reality;” (7) an excessive reliance on, and trust in, theoretical or conceptual models; and (8) reduced potential for lifelong learning through observation and analysis. Field courses need not be costly or difficult, but the instructor must be willing to adapt to the uncertainty and problems associated with field measurements. A recently updated course on watershed measurements at Colorado State University illustrates the type of field courses which can be developed if there is the necessary commitment and flexibility. The lack of a current text can be overcome by assembling selected portions of existing government documents, and a sample bibliography is included. 相似文献
993.
新疆是我国自然灾害群生的典型地区和频发地区,每年自然灾害造成的损失巨大。在未来十年灾害形势十分严峻的背景下,为参与联合国倡义的“国际减灾十年”活动和推动新疆的减轻工作,我们对新疆1949~1990年主要灾害进行了分析研究和统计,并对今后的减灾工作提出了建议。 相似文献
994.
David W. York Benjamin C. Dysart Lawrence W. Gahan 《Journal of the American Water Resources Association》1977,13(2):283-298
ABSTRACT: The previous paper in this two-part series presented the basic information of a newly developed mathematical model of multiple-use in natural areas. The model is a unified system for the assessment of cases where development is proposed for relatively natural areas. This paper presents the results of an application of the model to a study of the proposed timber harvest in the Great Santec Swamp in South Carolina. This was done in an effort to demonstrate the utility of the model as a planning and assessment tool. Four potential uses of the Swamp were investigated: logging of hardwood saw timber, hunting, fishing, and nature observation. The model system proved to be extremely useful in the evaluation of potential management schemes and in the selection of the most promising or optimal management plan. 相似文献
995.
Aliakbar Malekuti Gerald F. Gifford 《Journal of the American Water Resources Association》1978,14(1):195-205
Abstract: Foliage and litter leachate from selected natural vegetation in the Price River Basin (within the Upper Colorado River basin) was studied to determine the probable impact of plants on the amount of diffuse salt movement from rangeland watersheds. Calculations using concentrations of various leachates and characteristics of range sites expected to be high salt annual salt load to the Price River. It was therefore concluded that plants are not a significant source of diffuse salt within the Colorado River Basin. 相似文献
996.
Jay R. Stauffer Kenneth L. Dickson John Cairns 《Journal of the American Water Resources Association》1974,10(5):860-876
ABSTRACT. Studies were conducted to determine the distribution of fish in the New and East Rivers in relation to thermal discharges from Appalachian Power Company's fossil fuel plant at Glen Lyn, Virginia. Over 15,300 specimens representing 41 species were collected with seines, electrogear and rotenone at six sampling locations from February, 1973 to October 1973. Sampling frequency was designed to evaluate the effects of ambient temperature upon preferred temperature. Diversity indices were calculated for each location. There was a slight decrease in the diversity indices for those stations located in the thermal discharge. Condition coefficients calculated for Notropis albeolus Jordan, Notropis rubellus Aqasaiz, Notropis spilopterus Cope, Ictalurus punctatus Rafinesque, and Etheostoma blennioides Rafuesque were found to be significantly (p =.05) lower in the thermal discharge for all species tested except E. blennioides. Temperatures were plotted against frequency of capture to determine a particular species temperature selection from field data and indicated that: (1) Some species avoided high temperatures (i.e., Curnpostoma anomalum Rafuesque). (2) Some species were attracted to high temperatures (i.e., Ictalurus punctatus). (3) Some species distribution was not effected by temperatures (i.e., Notropis spilopterus). 相似文献
997.
J. A. Carfrae L. J. Sheppard J. A. Raven I. D. Leith W. Stein A. Crossley M. Theobald 《Water, Air, & Soil Pollution: Focus》2004,4(6):229-239
This paper reports data from a field study investigating the impacts of elevated ammonia (NH3) deposition on Calluna vulgaris growing on an ombrotrophic peat bog in S.E. Scotland. Shoot extension, foliar N concentrations, chlorophyll concentration and chlorophyll fluorescence were measured during the second growing season of exposure to a gradient of ammonia concentrations. Results indicate that NH3 increases growth between 150–200 kg N ha–1y–1 cumulative deposition. Foliar N content increased significantly in response to NH3 cumulative deposition up to 400 kg N ha–1 y–1 whereas chlorophyll a content significantly decreased. Measurements of Fv/Fm suggest that although NH3 exposure altered the growth and reduced chlorophyll a, the efficiency of photosystem II was insensitive to NH3-N deposition at this stage. 相似文献
998.
999.
本文分析了福建省农业自然资源利用中存在的突出问题及其形成原因,并根据持续发展新模式提出了持续利用的对策。 相似文献
1000.
城市地下水流场人工调控与减灾方案 总被引:2,自引:1,他引:1
以郑州市为例,针对城市区域长期过量开采地下水导致的一系列严重的环境地质灾害,诸如地下水水位持续下降形成区域地下水降落漏斗并不断扩张、含水层疏干、供水井吊泵、泉水断流、地下建筑工程浸没、地面沉降和塌陷等,探讨了城市地下水流场人工调控的减灾方案。建立了地下水系统的准三维动态数值仿真模型,以非均质各向同性渗流模型仿真地下水流,用不规则三角网格有限差分法求解了三维数值仿真模型。先解逆问题反求参数,再解正问题计算地下水各项资源量,数值仿真预报地下水渗流场至1998年。在此基础上,通过地下水渗流场的宏观调控与优化管理,使研究区内不合理开采地下水资源所引发的环境灾害减小到最低程度,为郑州市的环境减灾工作提供了科学依据。 相似文献