共查询到18条相似文献,搜索用时 437 毫秒
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针对城市饮用水水源地富营养化评价问题,以安徽省滁州市城区的西涧湖和沙河集水库两处饮用水水源地为例,在运用权重法定性确定富营养化评价因子影响程度的基础上,利用集对分析法建立了城市饮用水水源地富营养化评价的五元联系数评价模型,将水体富营养化评价因子和水质富营养化的分级标准作为集对,从而实现对水体富营养化等级的评价。研究结果表明,西涧湖和沙河集水库评价因子的五元联系数分别为(0.024,0.429,0.375,0.171,0)、(0,0.472,0.366,0.163,0);在置信度取0.7的情况下,西涧湖和沙河集水库的富营养化状态均为中营养,可见该方法评价结果直观、准确,为水源地富营养化评价及水质防护提供了理论依据。 相似文献
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在综合考虑张集水源地水质主要影响因素的基础上,选取水体的Cl-、SO2-4、矿化度、总硬度、NH+4、CODMn、F-等7个指标作为评价因子,通过组合赋权法确定各水质评价指标权重系数,基于理想点法基本原理计算待评价水体的理想点贴近度,建立水质综合评价模型,从而给出水质综合评价结果。将该方法应用于张集水源地水体水质评价中,结果表明该方法的综合评价结果与实际相符,证明运用组合赋权-理想点法进行水质综合评价是可行的。 相似文献
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长潭水库富营养化评价及防治对策 总被引:1,自引:0,他引:1
针对近年来长潭水库水质的富营养化现象,分析了三个常规监测断面2007~2011年间各项水质指标年际变化趋势,利用水库营养状态评价标准及分级方法对长潭水库水质的营养水平进行评价,得出其水体现状为中营养状态,水质变化的主要原因为上游来水携带的污染物,尤其是农业面源污染是造成水体富营养化的主导因素,并从控制污染源及清除底泥等方面提出相应的解决措施。 相似文献
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小型景观湖泊已成为城市生态景观的重要组成部分,但因自身特点决定了其易受人为因素影响而导致水质变差,甚至丧失景观水体的功能,因此有必要研究小型景观湖泊的水质状况及其富营养化程度的影响因素。以郑州大学眉湖为例,进行多次定期水环境监测试验,在分析水质指标的时空分布及变化规律的基础上,分别采用单指标评价法和综合营养状态指数法评价其水体的水质状况及富营养化程度。结果表明,CODCr、BOD5、TP、TN、NH3-N等主要污染物的浓度与禽类、鱼类和水生植物的分布密切相关,在监测时段内眉湖整体水质状况呈恶化趋势,从中营养状态变为轻富营养状态。最后,有针对性地提出了改善策略和保护措施,以期为小型景观湖泊的运行管理提供依据和参考。 相似文献
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研究辽河水体中磷元素的迁移转化,营养物质的结构与组成,分析辽河沉积物-水界面磷的类型,影响磷元素含量的因素和产生富营养化的原因,系统概括了磷元素迁移转化的规律. 相似文献
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基于EFDC模型的天镜湖水动力优化调控方案研究 总被引:3,自引:0,他引:3
太仓市天镜湖以长江水为水源,补水量只能维持蒸发渗透水量,湖水基本不动,水体极易处于高度富营养化状态。针对该湖现有问题,利用环境流体力学模型(EFDC模型)建立了天镜湖的三维非稳态水量、水龄、污染物颗粒追踪数学模型,对天镜湖水动力优化调控方案进行了模拟(模拟内容包括水位、流速和水龄)。模拟结果表明,通过浏河闸开启向天镜湖引水能够在一定程度上加强湖入口和中心区域的水体流动性能,且浏河闸开启的时间越长效果越好,但引水对天镜湖内部(远离入口处)区域的水动力无明显的改善作用;在西南风条件下,开启浏河闸引水对湖区的水动力改善效果最好;在现状条件下,湖区中存在多处水体交换差的区域(集中在湖周边和远离入口的地方),可能成为天镜湖潜在的水体富营养化高发区。 相似文献
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巢湖受周围城市工业化及农业生产迅速发展的影响,湖区及流域的生态环境发生了巨大变化,尤其是近几年巢湖水质达到重富营养化水平。引江济巢工程是改善巢湖水质的重要工程措施,采用EFDC生态动力学模型模拟了巢湖不同调水流量、调水线路、调水时间对水环境的影响。结果表明,引江济巢工程在一定程度、时间上使巢湖湖区水质发生一定程度的改善,但若入湖水质不达标,调水也增加了巢湖的富营养化风险。 相似文献
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Soil organic carbon changes in the cultivation of energy crops: Implications for GHG balances and soil quality for use in LCA 总被引:1,自引:0,他引:1
The environmental impact of different land-use systems for energy, up to the farm or forest “gate”, has been quantified with Life Cycle Assessment (LCA). Four representative crops are considered: OilSeed Rape (OSR), Miscanthus, Short-Rotation Coppice (SRC) willow and forest residues. The focus of the LCA is on changes in Soil Organic Carbon (SOC) but energy use, emissions of GreenHouse Gases (GHGs), acidification and eutrophication are also considered. In addition to providing an indicator of soil quality, changes in SOC are shown to have a dominant effect on total GHG emissions. Miscanthus is the best land-use option for GHG emissions and soil quality as it sequesters C at a higher rate than the other crops, but this has to be weighed against other environmental impacts where Miscanthus performs worse, such as acidification and eutrophication. OSR shows the worst performance across all categories. Because forest residues are treated as a by-product, their environmental impacts are small in all categories. The analysis highlights the need for detailed site-specific modelling of SOC changes, and for consequential LCAs of the whole fuel cycle including transport and use. 相似文献
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The cultivation of giant reed lignocellulosic feedstock on marginal land, appears of great interest in the Mediterranean basin, due to its high production potential under drought conditions. Starting from a three years field survey, in this paper a LCA was applied to the overall 15 years life cycle of a Mediterranean giant reed cultivation in Southern Italy, including Direct Field Emissions (DFE) and non-productive phases of cultivation.Agricultural practices performed yearly for field maintenance (FM-urea fertilization) and harvest operation (HO) shared the largest part of total burdens, nonetheless, the impact of crop establishment and final removal appeared significant. FM was strongly affected by DFE of soil biogenic N2O and fossil CO2 (about 23% and 9% of total Climate change, respectively) and volatilized NH3 (about 69%, 42% and 35% of total impact for Terrestrial acidification, Particulate matter formation and Marine eutrophication, respectively). For Marine eutrophication, also nitrate leaching in the plantation year, affected significantly the overall life cycle. Differently DFE linked to field application of K-P fertilizers for seedbed preparation (P and heavy metal emissions) and pest for final eradication (glyphosate emission), appeared more circumscribed.The study highlighted the need to carefully approach to soil carbon storage, and disclosed to be sensitive to uncertainty linked to DFE and crop yield pattern estimation. 相似文献