【作者】 黄宏；

【导师】 吕军；

【作者基本信息】 浙江大学 ， 水资源利用与保护， 2014， 博士

【摘要】 在点源污染逐渐得到控制的情况下,氮、磷等农业非点源营养物已成为水体富营养化的主要原因。汤浦水库位于曹娥江支流小舜江上游,是虞绍平原近300万人的主要饮用水源之一。水库运行十多年来,库体及上游支流大部分水质指标常年达到Ⅰ类标准,总氮则在Ⅳ类和劣Ⅴ类之间。本文针对汤浦水库流域总氮浓度常年超标的现状,开展氮污染定量溯源和分区分类控制研究。核心内容包括水环境容量计算、地表水和地下水污染源污染贡献率分割、地表水污染分类源解析、水环境容量和减排责任分配等。主要结果有：采用狄龙模型计算了汤浦水库总氮的水环境容量。以总氮浓度的Ⅱ类水质为标准(GB3838-2002),且分别在90%、75%和50%保证率的年径流量作为入库的水量条件下,汤浦水库的总氮水环境容量分别为402ton、580ton和679ton。应用ReNuMa模型模拟了汤浦水库流域主要入库河流双江溪的水文过程和总氮负荷。生活污源、地表水和地下水年平均贡献率分别为11.1±1.1%、34.3±8.9%和54.4+10.4%。水田、旱地、园地、林地、灌木地、草地、水域和建设用地对地表水总氮的年平均贡献率分别为16.9±1.5%、10.6±0.4%、6.4±0.1%、38.9±2.6%、13.4±0.2%、0.2±0.01%、2.0±0.3%和11.6±0.7%。情景模拟结果表明,所有农用地都转为林地,并加上生活污染源得到完全控制,总氮年负荷量削减率才达到22.1%。这解释了自水库建成以来污染控制力度不断加大,但水库总氮污染仍然居高不下的原因。鉴于流域模型不易推广应用(数据要求高、参数过多、校正和验证困难等),初步建立了一套普适而又相对简单的流域尺度氮污染分区分类源解析方法。首先,综合应用数字滤波技术和统计学方法,建立了生活点源、地表水污染源和地下水污染源对河流总氮贡献率的分割模型；然后采用遗传算法,优化求解各种土地利用类型的营养物入河系数；最后通过输出系数模型实现非点源污染物的分区分类溯源。双江溪流域年平均生活点源污染、地表水污染和地下水污染对TN入河量的年均贡献率为6.9±1.3%、28.2±2.7%和64.9±4.0%。水田、旱地、园地、林地、灌木地、草地、水域和建设用地年平均TN入河量分别为15.48±1.49kg.hm-2、3.74±0.36kg.hm-2、9.74±0.93kg.hm-2、2.03±0.19kg.hm-2、12.59±1.21kg.hm-2、11.73±1.13kg.hm-2、16.88±1.63kg·hm-2和11.75±1.14/kg.hm-2。在搞清楚流域非点源污染过程以后,水环境容量的公平分配和减排责任的认定将是水质控制的核心问题。基尼系数法已被广泛应用于水环境容量分配中,然而在同时考虑多个分配指标是,各个优化目标直接往往会相互矛盾。为解决这个问题,本文建立了基于多维基尼系数法的水环境容量分配模型,并开发了专门的软件。考虑到地下水污染的滞后性,提出了可分配水环境容量的概念,即将实际水环境容量扣除地下水的贡献量,才是可分配水环境容量。在总氮达到Ⅱ类水质标准,再以90%、75%和50%保证率的年径流量作为入库的水量条件下,汤浦水库可分配的总氮水环境容量分别为-30ton、148ton和247ton。在总氮达到Ⅱ类水质标准,以及50%保证率的年径流量作为入库的水量条件下,全流域地表水总氮入河量需要削减-68.5ton,削减率为-30.9%,全流域仍有剩余的水环境容量可以分配。运用基于基尼系数法的水环境容量分配模型,得出王院乡、竹溪乡、谷来镇、稽东镇、王坛镇和平水镇分别需要减排2.4ton、2.6ton、-2.5ton、-20.3ton、-37.2ton和-13.5ton,减排率分别为27.5%、21.2%、-4.0%、-35.2%、-63.1%和-59.9%。最后,还针对各乡镇的实际情况讨论了减排方法与措施。更多还原

【Abstract】 Under the condition that the point source pollution has been gradually controlled, the non-point source pollution becomes the major cause of water eutrophication. Tangpu Reservoir is the important drinking water source for3million people in Yushao Plain, located in the upstream of Xiaoshun River, one of the major tributaries of Cao’E River. Since its operation for more than ten years ago, most of the water quality indexes of the reservoir and the tributaries meet Grade I of environmental guideline of national quality standards for surface waters, China (GB3838-2002). However, the concentration of Total nitrogen (TN) has always been in high level, ranging from Grade IV to worse than Grade V. Aiming at the status aqo of heavy TN pollution in Tangpu Reservoir Watershed, this paper carried out the research on the quantitative source apportionment and control of TN. The major contents include water environmental capacity calculating, partition of the contributions of surface water and base flow, source apportionment of surface water pollution, and the allocation of water environmental capacity, etc. The major results are as follows:Applied Dillion Model to calculate the water environmental capacity of TN in Tangpu Reservoir. T With the goal of TN concentration reaches Grade Ⅱ, in conditions the inflows equal to90%,75%and50%guarantees of annual runoff volumes, the water environmental capacities were402ton,580ton and679ton, respectively.Applied ReNuMa model in the simulation of hydrological process and TN load in Tangpu Reservoir Watershed. Domestic pollution source, surface water source and base flow source accounted for11.1±1.1%,34.3±8.9%and54.4±10.4%to annual TN inputs to reservoir, while irrigated land, dry land, garden, forest, shrub land, grass land, waters and construction land contributed for16.9±1.5%,10.6±0.4%,6.4±0.1%,38.9±2.6%,13.4±0.2%,0.2±0.01%,2.0±0.3%and11.6±0.7%, respectively. The results of scene simulations showed that the highest reducing rate of TN was22.1%by means of land use conversion, explaining the reason for TN concentration was always in high level even if many pollution control measurements had been putting into practice in the past ten years.Established a universal yet simple series of methodologies for quantitative source apportionment of TN according to the regions and pollution sources in watershed scale. Firstly, the contributions of domestic pollution source, surface water source and base flow source to riverine TN was quantitatively separate by means of digital filtering and statistical method. And then, the export coefficients of various landuses were solved by modern optimization algorithm of genetic algorithm. Domestic pollution source, surface water source and base flow source accounted for6.9±1.3%,28.2±2.7%and64.9±4.0%to annual riverine TN. In consideration of the time lag of base flow source pollution, the TN pollution level in this watershed would not be decreased in near future. This conclusion was coinciding with the scene simulation results of ReNuMa model. The annual export coefficients of irrigated land, dry land, garden, forest, shrub land, grass land, waters and construction land were15.48±1.49kg.hm-2,3.74±0.36kg.hm-2,9.74±0.93kg.hm-2,2.03±0.19kg.hm-2,12.59±1.21kg.hm-2,11.73±1.13kg.hm-2,16.88±1.63kg.hm-2and11.75±1.14/kg.hm-2, respectively.The fair allocation of water environmental capacity and the confirmation of reduction responsibility were the core issues after the processes of non-point source pollution had been quantified. GiNi coefficient method had been widly applied in the field. However, the traditional GiNi coefficient method was based on two dimensional plane. In order to deal with this problem, we established a water environmental capacity allocation model based on multi-dimensional GiNi coefficient method, making an advance in water environment capacity allocation. In order to expand the application of this model, a softwere was developed.Formulated a TN reduction program according to regions and sources in watershed scale. In consideration of the time lag of base flow source pollution, proposed a concept namely "realistic allocatable water environmental capacity", which was the realistic water environmental capacity minus the portion of base flow source. In conditions the inflows equal to90%,75%and50%guarantees of annual runoff volumes, the realistic allocatable water environmental capacity were-30ton,148ton and247ton, respectively. With the goal of TN concentration reaches Grade Ⅱ, and in conditions the inflows equal to50%guarantees of annual runoff volumes, the total reduction amount of TN was-68.5ton, accounted for-30.9%of the surface source TN. In according to the Water environmental capacity allocation system based on multi-dimensional GiNi coefficient method, regions of Wangyan, Zhuxi, Gulai, Jidong, Wangtan and Pingshui in the watershed should reduce for2.4ton,2.6ton,-2.5ton,-20.3ton,-37.2ton and-13.5ton, respectively, and accounted for27.5%,21.2%,-4.0%,-35.2%,-63.1%and-59.9%to the total reduction amount, respectively. Finally, measurements for TN reduction in according to different regions and sources were proposed.更多还原