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阐述小浪底水利枢纽工程施工区、库区和移民安置区环境管理体系的建立后,对诱发地震进行监测、引入环境监理机制,加强现场监督协调,对水体、大气、噪声污染采取应对措施,对固体废弃物进行强化处理,开展系统化、规模化的水土保持措施建设和公共健康保障等措施,使小浪底工程建设对生态环境的不利影响得到预防和治理,施工区及周边生态明显改善,移民安置区可能发生环境影响得到有效控制,环境管理工作取得良好的效果。 相似文献
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人口的大量增加,城市的迅速扩张,需水量增加,水资源过度地被开发、水环境恶化,导致人类可以利用的水资源越来越少,水资源保护实为重中之重。流域水资源的保护一度主要侧重于水质的保护,水量保护与恢复没有得到应有的关注。根据水资源量的特征和保护的意义,分析水资源量保护和恢复影响因素,探讨水资源保护的相关问题。 相似文献
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Pollutant load reductions are often required to restore aquatic ecosystems experiencing eutrophication. Loads can be estimated using watershed models or data from monitoring stations, however data availability can limit the timeliness or comprehensiveness of the load estimates. We developed an approach to address this challenge that used watershed model results to estimate the proportion of annual nonpoint source nitrogen (N), phosphorus (P) and sediment (Sed) loads derived from unmonitored catchments. This proportion was multiplied by the nonpoint portion of United States Geological Survey (USGS) estimated annual river loads to account for annual variation in hydrologic conditions. Total loads were calculated as the sum of measured river loads, reported point sources from unmonitored areas and the estimated nonpoint source loads from unmonitored catchments. We applied this approach to the Chesapeake Bay because of its socio‐economic and ecological importance. Median watershed loads for N, P and Sed were 140, 6.4 and 3030 Mg year?1, respectively (1990–2004). Nonpoint source loads from the monitored areas constituted the greatest source of N, P and Sed (55, 47 and 74% respectively) to the Bay. The high N, P and Sed yield rates (7.3, 0.38 and 99 kg ha?1 year?1, respectively) from nonpoint loads originating from unmonitored areas near the Bay resulted in 25, 32 and 26% (N, P and Sed, respectively) of the Bay's total loads (excluding direct atmospheric deposition, shoreline erosion and oceanic inputs). Disproportionately high loads of P and Seds were associated with years that experienced elevated discharge whereas N loads were directly related to discharge. Error estimates indicated that our methods were most reliable for N (±6%) but reasonable for P (±22%) and provide an effective technique for the timely estimation of pollutant loads from watersheds with unmonitored catchments. Management strategies that decrease N deposition and reduce runoff to control P and Sed transport will effectively reduce pollutant loads. Published in 2010 by John Wiley & Sons, Ltd. 相似文献
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River channel substrate size and mobility are important to Atlantic salmon spawning and rearing success. We compare morphology and bed sediment between two North American Atlantic coastal streams (Narraguagus River, Maine, USA and Jacquet River, New Brunswick, Canada). The watersheds have similar drainage areas and mean annual precipitation, but differing relief structure, channel longitudinal profiles and numbers of returning salmon. The lower‐relief Narraguagus River is segmented into steeper (gradient >0.002) and flatter reaches (gradient <0.0005). Flat reaches, including mainstem lakes, act as sediment sinks, preventing the continuity of downstream sediment transport. Based on field measurements, the Narraguagus River has a larger high‐flow width to depth ratio than the Jacquet River, but this difference is principally the result of outliers from low‐gradient channel reaches. Measurements of substrate grain size reveal finer river‐bed sediments on the Narraguagus River, however, Shields parameter calculations indicate that bed sediment should be mobile during high flows in both streams. We use the Shields equation to predict grain size based on channel slope, width and drainage area measured from digital elevation models (DEM) and aerial photographs. Predictions of median grain size agree with field measurements within a factor of 2 for 62–70% of the survey stations. We suggest ways that model misfits may provide opportunities to prioritize reach‐based restoration efforts. Based on expected grain size, we estimate 62% spawning and 68% rearing habitat along the length of the Narraguagus River, and 28 and 95% respectively on the Jacquet. Overall, glacial history and relief structure appear to be the first‐order controls on substrate grain size and habitat quality in these two rivers. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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YU Huiqing HE Yanxin HUANG Yuguang LI Shu NIU Taotao ZHANG Hao JING Minna 《水资源与水工程学报》2011,22(2):103-105
论述了北方某镇采用无动力处理技术处理农村生活污水的方法,工艺流程为新型化粪池-人工湿地-氧化塘工艺。运行结果表明,工程出水中污染物日均浓度COD为35~55 mg/L、BOD5为10~20 mg/L、SS为5~18mg/L、氨氮为3~5 mg/L,均能达到《农田灌溉水质标准》(GB 5084-2005)中蔬菜a标准。处理后的出水用于周边农田灌溉,既治理了污染,又节约了资源,是绿色、低碳城镇建设的一个典范,非常适合北方乡镇新农村建设的生活污水处理和利用。 相似文献
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介绍浙江省丽水市瓯江水生态系统现状,根据瓯江水生态系统保护与修复的目标,提出瓯江水生态系统保护与修复的措施:对土地利用进行分级控制,构建水生态系统安全格局,编制瓯江水生态系统的保护与修复总体规划,分段实施水生态系统保护与修复,开展瓯江水生态系统保护与修复的制度与机制建设。此外,总结了瓯江水生态系统保护与修复工作的成效与存在问题。 相似文献