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391.
The USGS Water Availability and Use Science Program: Needs,Establishment, and Goals of a Water Census
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Ari M. Michelsen Sonya Jones Eric Evenson David Blodgett 《Journal of the American Water Resources Association》2016,52(4):836-844
Many reports have recognized the need for a national water census for the United States and have called upon the U.S. Geological Survey to undertake this challenge. For example, the National Science and Technology Council stated: “The United States has a strong need for an ongoing census of water that describes the status of our Nation's water resource at any point in time and identifies trends over time.” Responding to the need for this information, the U.S. Congress established the SECURE Water Act. The directives are to provide a more accurate assessment of the status of the water resources of the United States; determine the quantity of water available for beneficial uses; identify long‐term trends in water availability; assist in determination of the quality of the water resources; and develop the basis for an improved ability to forecast the availability of water for future economic, energy production, and environmental uses. This article provides summary and new information on the process and progress on work to estimate water budget components nationwide, involvement of stakeholder interests, efforts to examine water‐use characteristics throughout the Nation, studies of water availability in geographically focused areas and the initiation of methods to provide open access to existing and new water resources information contributing to Open Water Data Initiative (OWDI) efforts and objectives. 相似文献
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郭燕 《再生资源与循环经济》2014,(3):29-33
北京和上海在迈向国际化大都市进程中,随着人口的迅速增长,生活垃圾产生量与日俱增,垃圾减量从源头做起。旧衣物作为可回收、可再利用资源,现有的垃圾分类标准和回收箱的设置,不利于旧衣物的回收和再利用。目前,北京和上海在政府的支持和推动下,设专项开展旧衣物回收试点工作,已取得良好的效果。未来,如何使北京和上海旧衣物回收再利用成为一种常态,仍需政府的支持和全社会的共同参与。 相似文献
394.
One of the major interests of governments in the area of environmental protection is to reduce greenhouse gas (GHG) emissions and air pollutants’ emissions (HC, CO, NOx, PM, and SOx) from vehicles. This paper aims at evaluating the efficiency of green and diesel vehicles. Two hundred fifty vehicles were selected for comparison study. The results show that the efficiency of each type of vehicle hardly differed in 2008 and 2009, but the gap between green and diesel vehicles became significant in 2010–2012. The results also indicate that larger automotive companies and smaller green vehicles show higher efficiency in recent years, whereas the type of green vehicles and the origin of automotive companies are not significantly related to the efficiency score of green vehicles. These findings provide more information for understanding differences in green vehicles. 相似文献
395.
Patricia V. Cline 《Environmental Forensics》2013,14(2):161-168
Making defensible risk-based decisions is a complex process that incorporates risk assessment into a risk management framework. Many site investigations require additional study, negotiations and/or actions for arsenic detected in soil samples, in many cases where no process related sources are identified and no other chemicals of concern are identified. Regulatory agencies develop guidance to standardize approaches to risk-based site investigations that focus on achieving "safe" concentrations. For arsenic, the action level is frequently in the "gray region", a U.S. Environmental Protection Agency (USEPA) term associated with a region of high uncertainty for risk management decisions in the "decision performance curve" associated with the data quality objective (DQO) process. Recognizing the conservative nature of the risk-based screening value for arsenic, approaches to enforce this level (or proof of comparability to natural background) may have numerous consequences including ineffective use of resources, stigmas on properties or actions at industrial or hazardous sites that are inconsistent with their regional setting. Florida has developed regulations and guidance on investigation of brownfield sites and has supported a study by the University of Florida (UF) to evaluate natural background concentrations in Florida soils. This paper discusses the sources of uncertainty near the soil cleanup target levels (SCTLs) in the Florida decision-making framework. 相似文献
396.
西北典型村镇集雨窖水水质变化及特性 总被引:4,自引:0,他引:4
为研究西北村镇集雨窖水的水质状况和污染物变化规律,在2012年8月份的暴雨过后,对会宁县某农户3口不同集雨面(屋顶庭院、山坡土路、打麦场)水窖进行了长期水质监测分析。结果表明,窖水的水质变化分为3个阶段:以物理沉降为主的初期沉降阶段(0~15 d);以生物降解为主的中间过渡阶段(15~100 d)及水质基本不变的后期稳定阶段(100~250 d)。浊度与CODMn、NH3-N、细菌总数之间的相关性较好,相关系数达到0.60~0.96。窖水水质受集雨面特征影响较大,屋顶庭院水窖水质最优且最早到达稳定期,后期基本满足农村饮用水卫生标准;山坡土路面及打麦场水窖水质分别满足地表水环境质量Ⅲ、Ⅳ类标准。研究结论可为水窖的使用和管理、开发相应的水处理工艺及设备提供科学依据。 相似文献
397.
突发事件应对的物资保障分析 总被引:2,自引:1,他引:1
周定平 《中国安全科学学报》2008,18(3):5-9
从突发事件应对物资保障的特征与价值入手,提出突发事件应对物资保障的基本要求;根据当前我国突发事件应对的物资保障中暴露出来的问题,揭示引发当前突发事件应对物资保障不足的深层次原因;从应对物资的需求、筹集、配置、调度等方面分析,提出我国突发事件应对的物资保障体系的架构设想。有关研究成果将对我国突发事件应对物资保障具有一定的启发和参考意义。 相似文献
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随着城市的快速发展,城市生活垃圾对环境的危害越来越大,已经成为影响城市居住环境的重要污染源,如何进行城市生活垃圾的收集与处理显得至关重要。米东区作为乌鲁木齐市新型工业城区的代表,其经济虽然取得了飞速发展,但其城市居住环境却未得到足够地重视。鉴于此,围绕乌鲁木齐市新型工业城区的生活垃圾分类收集和处理现状展开了社会调查,选取乌鲁木齐市米东区作为靶区,随机选取70户人家进行了入户问卷调查,对调查结果进行了统计分析,得出了乌鲁木齐市米东区家庭生活垃圾分类收集及处理的特点,进而指出了新型工业城区垃圾分类工作存在的主要问题,根据影响城市家庭生活垃圾产生量的因素,针对如何更好的实现垃圾的分类收集工作提出了相应的建议。 相似文献