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71.
The microclimate of beach and foredune areas of North Padre Island along the mid-Texas coast was found to be greatly modified by vehicular and pedestrian traffic during investigations made from late fall to early summer 1973–74. The primary effect of human activity on microclimate was expressed as reduced cover and species diversity of the vegetation. As the intensity of human activity increased, elevation, especially of areas near the beach, was decreased, whereas average wind velocities near the ground surface, evaporation, atmospheric salinity near the ground surface, wind-carried sand particles near the ground surface, soil salinity, soil pH, average soil temperature and range in temperature, soil bulk density, and soil-water contents were increased.  相似文献   
72.
ABSTRACT: Major water rights adjudications involving the Little Colorado River Basin and Gila River Basin are presently underway within Arizona. Water resource managers are faced with the prospect of evaluating and regulating tens of thousands of water diversions and uses. Stockponds comprise a large percentage of the total number of water diversions within these basins. Water balance studies conducted on the Little Colorado River watershed above Lyman Lake and on the Gila River watershed above Solomon, Arizona, indicate that the impact of stockponds on the water available to downstream users is insignificant when compared to total watershed production. Considering that there are an estimated 25,000 stockponds in the Gila River basin alone, rigorous case-by-case investigations and stringent regulation of individual stockponds may be impractical and unwarranted. Therefore, stock-pond claims within the context of the general adjudication process may be effectively handled by partial summary judgment, thereby allowing the court to concentrate on major water users and water rights issues.  相似文献   
73.
ABSTRACT: The traditional solution to stormwater runoff from housing developments has been stormwater sewer systems. A newer and increasingly popular solution is some sort of impoundment or “lake” within the development, which is thought to be cheaper, to provide recreation, to improve the aesthetics of the environment, and to increase property values. Little is known of the acceptability of these to public officials, developers, or potential residents, or of their policy implications. Two such developments in Mississauga, Ontario, were studied, in terms of the perceptions and opinions of a random sample of residents and of officials who had been involved in their planning and management. The areas have attracted a relatively young group, just beginning their child-bearing years, with relatively high income and education. The lakes appear to be popular, and relatively successful, especially the one which provides more recreational opportunities, and which has had fewer maintenance problems. The major problems are visual and safety. The City, and to some extent the developers, are seen as the appropriate groups to manage and maintain the lakes. Some suggestions, based on residents' and officials' responses, are presented for future designs and policy formulation.  相似文献   
74.
ABSTRACT: An input-output model was developed to predict changes in Salton Sea salinity and water level until the year 2000 due to proposed water conservation efforts and geothermal and solar pond energy developments. The model SALINP provided good agreement with the observed salinities for 1960–80. While SALINP was not overly sensitive to one-year changes in any of the major inputs, a change in the historical means of the Imperial Valley runoff and evaporative loss inputs produced a significant effect on future predictions. The proposed water conservation measures caused the predicted Salton Sea salinity for 2000 to greatly exceed 40,000 ppm, the level at which adverse effects to wildlife are believed to occur. The possible geothermal development also produced predicted salinities considerably above 40,000 ppm. The salinity predictions for solar ponds by themselves and in conjunction with geothermal development were below 45,000 ppm for 2000. The solar pond and geothermal combination also resulted in a predicted lowering of the “natural” water level by 5 to 7 feet by 2000.  相似文献   
75.
沈阳市固体废物处置中心对工业危险废物采用了安全土地填埋技术 ,它的主要特点是安全、工艺简单、可操作性强。能够杜绝危险废物渗析液下渗污染地下水 ,同时又避免了危险废物污染环境卫生。本文主要以沈阳工业危险废物处置填埋场为例 ,介绍安全土地填埋的技术要求、设计要点等  相似文献   
76.
吸收法和吸附法油气回收技术的联合应用   总被引:11,自引:0,他引:11  
介绍了吸收法、吸附法、冷凝法及膜法回收轻质油品蒸发排放出来的油气的回收机理和关键工艺设计数据,分析了在工程应用时存在的一些关键问题、回收效果影响因素。综合比较工业应用时的优缺点和适用范围,认为常压常温吸收法和活性炭吸附法回收技术可在工业实践中联合运用。应用油气回收装置将带来明显的社会效益、环境效益及经济效益。  相似文献   
77.
Abstract:  Installation and maintenance of stormwater ponds to detain and treat runoff from impervious surfaces is a common method of stormwater control in developed areas. That these ponds capture pollutants, however, is of concern for wildlife species that use the ponds, particularly pond-breeding amphibians. To assess the relative contribution of stormwater ponds to the persistence of amphibian populations in suburban landscapes, we compared amphibian use of stormwater ponds and other available wetlands in suburban and forested watersheds. We surveyed three suburban and three primarily forested first-order watersheds to identify all potential wetlands that might serve as breeding sites for pond-breeding amphibians. We performed call, egg-mass, and larval surveys to measure breeding effort at each wetland in spring and summer 2007 and 2008. In suburban watersheds most (89%) of the wetlands that had breeding activity were either stormwater ponds or otherwise artificial. This pattern was also evident in the forested watersheds, where amphibians were primarily found breeding in wetlands created by past human activity. Late-stage larvae were found only in anthropogenic wetlands in all study areas because the remaining natural wetlands did not hold water long enough for larvae to complete development. Our results suggest that in urban and suburban landscapes with naturally low densities of wetlands, wetlands created by current or historic land uses may be as important to amphibian conservation as natural wetlands or pools and that management strategies directed at urban and suburban landscapes should recognize and incorporate human-created wetlands.  相似文献   
78.
我国三等以上尾矿库均建成了尾矿库在线监测系统,为进一步提升尾矿库管控水平,提出可在在线监测系统基础上建设数字尾矿库工程的思路。数字尾矿库工程是借助全数字测量、遥感、地理信息系统或全球定位系统等现代化手段采集基础数据,实现尾矿库地形地势、水文气象、监测监控、调洪、尾矿坝稳定、风险分析、设备设施管理、应急培训等功能有机集成的统一管控平台。在总结数字尾矿库研究现状的基础上,借鉴水利水电工程中数字黄河、数字长江工程建设理论和方法,研究了数字山谷型尾矿库系统的功能和实现方法,提出了数字山谷型尾矿库系统的结构框架,并对数字平台建设、调洪演算实现、坝体稳定在线分析预警及应急培训等子系统的实现方法进行了深入研究,研究成果可为后期数字尾矿库建设提供参考。  相似文献   
79.
Temperature measurements were taken at three pilot-scale facultative ponds located at Esholt wastewater treatment works in West Yorkshire, UK over two one-year periods. The measurements were taken at different depths using a technology called Thermochron iButton. The iButton readings were compared with temperature measurements taken by a YSI sonde probe and maximum/minimum thermometers: they were found to be within 1 .C. In the temperature range 3.18 .C the mean weekly and monthly air temperatures were found to be good predictors for the mean weekly and monthly pond water-column temperatures. The level of stratification in the ponds under UK climatic conditions was assessed; the data revealed that the ponds remained thermally stratified for significant periods during the year despite their shallow depth.  相似文献   
80.
为系统掌握稳定塘的设计、运行规律,应用国家“六五”科技攻关9个稳定塘中试基地的运行数据,通过数据分析、综合,总结出稳定塘的数学模型和技术参数。确定了稳定塘型的依据,提出了全国范围稳定塘负荷的设计值。   相似文献   
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