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791.
India is fast finding its place in the industrialized world and that is beginning to raise its environmental consciousness. The Delphi technique was used to prioritize specific needs and articulate a sustainable urban improvement strategy for the city of Mumbai (formerly Bombay). The Delphi technique is a means of achieving consensual validity among raters by providing them feedback regarding other raters' responses. Mumbai has several indigenous environmental groups that were tapped for activists and leaders; the study was conducted using ten environmentalists. In the initial phases the responses resulted in a range of possible program alternatives. The last two stages helped to seek out information that generated a consensus on the part of the respondent group. Statistical analysis methods included a hierarchical cluster analysis, mean, median, mode, and percent of agreement calculations using SPSS software. The face-to-face discussion in phase 4 clarified some issues and helped the group as a whole to outline the strategy for putting in place the essential elements of a framework to improve the quality of life in an urban environment.  相似文献   
792.
Public participatory techniques have been the focus of a large and growing body of environmental literature. There is some consensus among those who study these techniques that there is a need to develop and implement new techniques that meet certain criteria. These include that the techniques be comfortable, convenient, and satisfying to participants. Authors have also frequently called for the use of deliberative techniques, which allow participants to express and listen to a variety of perspectives regarding the issue at hand. However, the literature on public participation lacks a set of widely applicable evaluation methods to determine whether participants in techniques find them comfortable, convenient, satisfying, or deliberative. This paper reports on the implementation of two different techniques that participants scored fairly high on all of these factors, as well as the scale-based survey questions developed to measure these factors.  相似文献   
793.
The endangered snail kite (Rostrhamus sociabilis) feeds primarily on the freshwater apple snail (Pomacea paludosa) in Florida. The nonindigenous, floating water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes) impede kites from finding snails. Effective control of these aquatic plants in the littoral zone of central and south Florida lakes benefits kites by maintaining open foraging habitat. However, incidental herbicide spraying of nesting substrates result in nest collapse when kites breed in nonwoody, emergent plants [cattail (Typha spp.) and giant bulrush (Scirpus validus)] in the outer littoral zone during lower lake levels. Many endangered species recovery plans and their implementation have experienced problems due to inaction and/or noncooperation by various governmental agencies and their personnel. Herein, we describe the development and implementation of a buffer zone strategy to prevent secondary impacts from an aquatic plant control program to snail kites nesting on lakes in central and south Florida. A strategy was jointly developed by personnel of five state and federal agencies to control herbicide application near kite nesting areas during the normal breeding season. Although requiring various modifications during its implementation, this cooperative effort successfully integrated aquatic plant control objectives with snail kite conservation on Lake Okeechobee during 1988. The program was expanded the following year to lakes Kissimmee and Tohopekaliga. Since the implementation of the snail kite impact preclusion program, no nest loss was attributed to incidental herbicide applications on lakes Okeechobee, Kissimmee, and Tohopekaliga.  相似文献   
794.
我国部分商品瓶装饮用水中挥发性有机物的研究   总被引:15,自引:1,他引:14  
应用Tekmar3000吹扫捕集-气相色谱质谱组合分析仪,参照USEPA的标准分析方法,对我国某些商品瓶装饮用水中挥发性有机物进行了定量分析,结果表明,其含量一般在1~8μg/L,其中普遍含有具三致潜力的卤代烃与苯系物。虽然这些毒理性指标均可达到我国瓶装饮用纯净水卫生标准,但与国外优质瓶装饮用水相比,存在明显的差距。瓶装饮用水中挥发性有机物主要与深度处理技术和组合工艺有关,可通过改进这些技术而得以有效控制。   相似文献   
795.
Significant annual variations in population size of most species were evident with greater abundance of most species in wet years. Habitat variables, particularly vegetation structure, were also an important determinant of the abundance of most bird species and tended to mask the impacts of the land use under investigation. Several bird species had benefited from the provision of permanent water at mining and pastoral sites. Other species utilized increased nesting or feeding opportunities associated with the mining operation and increased food supply at the pastoral sites. Crested bellbirds and mixed-feeding flocks of small insectivorous birds were apparently disadvantaged by mining and hence may be useful bioindicators of mining impacts. No bird species or community parameters were identified which could serve as useful early warning bioindicators of pastoral impacts.  相似文献   
796.
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798.
In this study, water quality and basin characteristics data from different basins of the Fish River basin, Baldwin County, Alabama, were used to develop a valuation model. This valuation model is based on the effectiveness of “contributing zones” identified and delineated using methods described by Basnyat and others (Environmental Management]1999] 23(4):539–549). The “contributing zone” delineation model suggests that depending on soil permeability, soil moisture, depth to water table, slope, and vegetation, buffer widths varying from 16 m to 104 m must be maintained to assimilate or detain more than 90% of the nitrate passing through the buffers. The economic model suggests the value of retiring lands (to create the buffers) varies from $0 to $3067 per ha, depending on the types of crops currently grown. The total value of retiring all areas identified by the contributing zone model is $1,125,639 for the study area. This land value will then form the basis for estimates of the costs of land management options for improving (or maintaining) water quality throughout the study area.  相似文献   
799.
Reestablishing Naturally Functioning Dunes on Developed Coasts   总被引:2,自引:0,他引:2  
Common beach management practices reduce the ecological values of coastal dunes. Mechanical beach cleaning eliminates incipient dunes, habitat for nesting birds, seed sources for pioneer dune colonizers and food for fauna, and artificially small, stabilized foredunes reduce the variability in microenvironments necessary for biodiversity. Recent initiatives for reducing coastal hazards, protecting nesting birds, and encouraging nature-based tourism provide incentive for the development of a restoration program for beaches and dunes that is compatible with human use. Suggested changes in management practice include restricting or rerouting pedestrian traffic, altering beach-cleaning procedures, using symbolic fences to allow for aeolian transport while preventing trampling of dunes, and eliminating or severely restricting exotic species. Landforms will be more natural in function and appearance but will be more dynamic, smaller and in a different position from those in natural areas. Research needs are specified for ecological, geomorphological, and attitudinal studies to support and inform restoration planning.  相似文献   
800.
实践证明,在市场经济条件下,运用经济手段管理森林防火工作,是使森林防火工作由单一行政命令的传统模式向经济、法律、行政相结合的新的森防管理模式转变的有效途径。  相似文献   
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