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971.
针对一年中长江原水和黄浦江原水的水质情况,进行了两种原水几种水质指标的对比分析,混凝沉淀后两种原水氨氮和CODMn的达标情况对比,以及不同水温对于两大原水浊度、氨氮和CODMn混凝效果的影响。结果表明,黄浦江原水的浊度、氨氮和CODMn一般比长江原水高,pH比长江原水低,经过混凝沉淀处理后长江原水氨氮和CODMn的达标率比黄浦江原水高,两种原水的浊度、氨氮和CODMn的去除率随水温的升高有增大的趋势,若两种原水进行混合,为保证其处理后水质达标,则黄浦江和长江原水的配比最好不能超过2∶8。 相似文献
972.
973.
介绍了火电厂烟气脱硫特许经营模式(BOOM)发展的必要性和特点,该方式可使国家、火电厂、脱硫公司三方受益。文章还介绍了烟气海水脱硫在国内外的技术进展,列举了火电厂烟气海水脱硫采用BOOM模式的实例。 相似文献
974.
上覆水营养盐浓度对底泥氮磷释放的影响 总被引:2,自引:0,他引:2
采用校园水体底泥进行上覆水营养盐浓度对底泥释放量之间的关系研究。结果表明,在本实验条件下,上覆水水质影响底泥氮、磷的释放,尤其显著影响氮、磷的初期释放;上覆水氮、磷的浓度越小,底泥氮、磷的释放量越大;上覆水氮、磷的浓度超过一定值,会抑制底泥氮、磷的释放。 相似文献
975.
Richard D. Horan James S. Shortle 《Journal of the American Water Resources Association》2011,47(1):59-69
Horan, Richard D. and James S. Shortle, 2011. Economic and Ecological Rules for Water Quality Trading. Journal of the American Water Resources Association (JAWRA) 47(1):59‐69. DOI: 10.1111/j.1752‐1688.2010.00463.x Abstract: Emissions trading in textbook form uses markets to achieve pollution targets cost‐efficiently. This result is accomplished in markets that regulators can implement without knowing pollution abatement costs. The theoretical promise of emissions trading, along with real‐world success stories from air emissions trading, has led to initiatives to use trading for water pollution control. Yet, trading, particularly when it involves nonpoint sources of pollution, requires significant departures from the textbook concept. This paper explores how features of water quality problems affect the design of markets for water pollution control relative to textbook emissions markets. Three fundamental design tasks that regulators must address for pollution trading to achieve an environmental goal at low cost are examined: (1) defining the point and nonpoint commodities to be traded, (2) defining rules governing commodity exchange, and (3) setting caps on the commodity supplies so as to achieve an environmental target. We show that the way in which these tasks are optimally addressed for water quality markets differs significantly from the textbook model and its real‐world analogs. We also show that the fundamental appeal of emissions trading is lost in the case of realistic water quality markets, as market designs that reduce the costs of achieving water quality goals may no longer be implementable without the regulatory authority having information on abatement costs. 相似文献
976.
Hydrologic and Phosphorus Export Behavior of Small Streams in Commercial Poultry‐Pasture Watersheds1
J. Joshua Romeis C. Rhett Jackson L. Mark Risse Andrew N. Sharpley David E. Radcliffe 《Journal of the American Water Resources Association》2011,47(2):367-385
Romeis, J. Joshua, C. Rhett Jackson, L. Mark Risse, Andrew N. Sharpley, and David E. Radcliffe, 2011. Hydrologic and Phosphorus Export Behavior of Small Streams in Commercial Poultry‐Pasture Watersheds. Journal of the American Water Resources Association (JAWRA) 1‐19. DOI: 10.1111/j.1752‐1688.2011.00521.x Abstract: Few watershed‐scale studies have evaluated phosphorus export in streamflow from commercial poultry‐pasture operations. Continuous streamflow and mixed‐frequency water quality datasets were collected from nine commercial poultry‐pasture (AG) and three forested (FORS) headwater streams (2.4‐44 ha) in the upper Etowah River basin of Georgia to estimate total P (TP) loads and examine variability of hydrologic response and water quality of storm and nonstorm‐flow regimes. Data collection duration ranged from 18 to 22 months, and approximately 1,600 water quality samples were collected. Significant (p < 0.1) inverse relationships were detected between peak flow response variables and both drainage area and fraction of forest cover. Order‐of‐magnitude differences in TP and dissolved reactive P (DRP) concentration were observed between AG and FORS sites and among AG sites. TP yields of FORS sites ranged from 0.01 to 0.1 kg P/ha. Yields of AG sites ranged from 0.031 to 3.17 kg P/ha (median = 0.354 kg P/ha). With 95% confidence intervals, AG yields ranged from 0.025 to 13.1 kg P/ha. These small‐watershed‐scale yields were similar to field‐scale yields measured in other studies in other regions. TP yields were significantly related to area‐weighted Mehlich‐1 soil test P concentrations (p = 0.0073) and base‐flow water sample P concentrations (p ≤ 0.0005). Water quality sampling during base‐flow conditions may be a useful screening tool for P risk‐based management programs. 相似文献
977.
Molly A. Maupin Tamara Ivahnenko 《Journal of the American Water Resources Association》2011,47(5):950-964
Maupin, Molly A. and Tamara Ivahnenko, 2011. Nutrient Loadings to Streams of the Continental United States From Municipal and Industrial Effluent. Journal of the American Water Resources Association (JAWRA) 47(5):950‐964. DOI: 10.1111/j.1752‐1688.2011.00576.x Abstract: Data from the United States Environmental Protection Agency Permit Compliance System national database were used to calculate annual total nitrogen (TN) and total phosphorus (TP) loads to surface waters from municipal and industrial facilities in six major regions of the United States for 1992, 1997, and 2002. Concentration and effluent flow data were examined for approximately 118,250 facilities in 45 states and the District of Columbia. Inconsistent and incomplete discharge locations, effluent flows, and effluent nutrient concentrations limited the use of these data for calculating nutrient loads. More concentrations were reported for major facilities, those discharging more than 1 million gallons per day, than for minor facilities, and more concentrations were reported for TP than for TN. Analytical methods to check and improve the quality of the Permit Compliance System data were used. Annual loads were calculated using “typical pollutant concentrations” to supplement missing concentrations based on the type and size of facilities. Annual nutrient loads for over 26,600 facilities were calculated for at least one of the three years. Sewage systems represented 74% of all TN loads and 58% of all TP loads. This work represents an initial set of data to develop a comprehensive and consistent national database of point‐source nutrient loads. These loads can be used to inform a wide range of water‐quality management, watershed modeling, and research efforts at multiple scales. 相似文献
978.
Stephen D. Preston Richard B. Alexander Gregory E. Schwarz Charles G. Crawford 《Journal of the American Water Resources Association》2011,47(5):891-915
Preston, Stephen D., Richard B. Alexander, Gregory E. Schwarz, and Charles G. Crawford, 2011. Factors Affecting Stream Nutrient Loads: A Synthesis of Regional SPARROW Model Results for the Continental United States. Journal of the American Water Resources Association (JAWRA) 47(5):891‐915. DOI: 10.1111/j.1752‐1688.2011.00577.x Abstract: We compared the results of 12 recently calibrated regional SPARROW (SPAtially Referenced Regressions On Watershed attributes) models covering most of the continental United States to evaluate the consistency and regional differences in factors affecting stream nutrient loads. The models – 6 for total nitrogen and 6 for total phosphorus – all provide similar levels of prediction accuracy, but those for major river basins in the eastern half of the country were somewhat more accurate. The models simulate long‐term mean annual stream nutrient loads as a function of a wide range of known sources and climatic (precipitation, temperature), landscape (e.g., soils, geology), and aquatic factors affecting nutrient fate and transport. The results confirm the dominant effects of urban and agricultural sources on stream nutrient loads nationally and regionally, but reveal considerable spatial variability in the specific types of sources that control water quality. These include regional differences in the relative importance of different types of urban (municipal and industrial point vs. diffuse urban runoff) and agriculture (crop cultivation vs. animal waste) sources, as well as the effects of atmospheric deposition, mining, and background (e.g., soil phosphorus) sources on stream nutrients. Overall, we found that the SPARROW model results provide a consistent set of information for identifying the major sources and environmental factors affecting nutrient fate and transport in United States watersheds at regional and subregional scales. 相似文献
979.
980.
小流域面源污染减控措施优化管理 总被引:3,自引:1,他引:2
以长春市重要饮用水源地石头口门水库的莫家沟小流域为研究区,选择横垄耕作、修建梯田、退耕还林、化肥减施和人工湿地5种措施进行磷素削减处理,共计21个措施组合方案;以实施措施的费用最小为目标函数,以水库水质TP浓度和采用不同措施的土地面积为约束条件,建立小流域出口水质优化管理模型。模拟计算3个阶段的可行性最优方案分别为:2011—2020年,选取措施为施肥量不变,现状梯田面积不变,坡度≤5°的耕地采取横垄耕作,其他退耕还林;2021—2030年,在第一阶段实施方案的基础上,新建人工湿地0.03 km2;2031—2050年,全部农田原位退耕还林,保持人工湿地面积不变,最终实现入库水质ρ(TP)≤0.01 mg.L-1的目标。化肥减施和梯田建设面积是影响方案选择的主要因素。 相似文献