【作者】 朱梅；

【导师】 吴敬学；

【作者基本信息】 中国农业科学院 ， 农业技术经济， 2011， 博士

【摘要】 中国是世界上水资源严重不足的国家之一,人均水资源占有量不足世界平均水平的三分之一。改革开放以来,随着经济突飞猛进的发展,水体污染的形势逐渐恶化。《2009年中国环境状况公报》显示,七大水系总体为轻度污染,海河水系为重度污染,是中国水污染最严重的流域,“有河皆干、有水皆污”是海河流域的真实写照。本文首次系统研究海河流域的农业非点源污染问题,估算农业非点源污染负荷量,评价农业非点源污染对水体污染的影响,并提出相应的管理和控制措施,填补了海河流域农业非点源污染研究的空白,为海河流域管理机构和各级政府确定水污染防治重点产业和重点区域,科学分配点源污染和非点源污染消减指标提供依据。本文通过分析评价现有大尺度流域非点源污染负荷估算方法,特别是在总结输出系数法优缺点的基础上,建立了适合现有数据条件并有一定精确性的大尺度流域农业非点源污染负荷估算方法——“三维”系数估算法。所谓“三维”有三层含义:一是根据水系和地形,把海河流域在三个尺度上分成估算单元;二是根据污染物来源,把农业非点源污染分成种植业、畜禽养殖和农村生活三个组成部分,分别估算污染负荷;三是根据非点源污染形成过程,把农业非点源污染分成产生、流失和入河三个阶段,分别估算污染负荷。本文的主要研究结论如下:1、关于海河流域农业非点源污染负荷量。2007年,海河流域农业非点源污染化学需氧量、总磷、总氮、氨氮产生量分别为774.1x10⁴ t、192.0 x10⁴ t、459.1x10⁴ t、67.8x10⁴ t;流失量分别为239.4x10⁴ t、4.5x10⁴ t、56.8x10⁴ t、6.2x10⁴ t;入河量分别为68.0x10⁴ t、0.9 x10⁴ t、8.6x10⁴ t、1.1x10⁴ t。2、关于非点源污染对水体污染的贡献。以海河流域多年平均地表水资源量来衡量,农业非点源入河污染物给水体带来的污染负荷为:化学需氧量31.5 mg·L^-1,总磷0.4 mg·L^-1,总氮4.0 mg·L^-1,氨氮0.5 mg·L^-1。参照地表水环境质量标准（GB3838-2002）三类水质标准,除氨氮外,各项污染指标均超过水质标准,农业非点源污染对水质的影响不容轻视。化学需氧量和氨氮主要来自点源污染,分别占62.0%和91.5%;总磷和总氮主要来自非点源污染,分别占60.2%和58.7%。由于海河流域水质主要超标项目中没有包括总磷和总氮,因此,点源污染是目前海河流域水体污染的主要原因。3、关于农业非点源污染等标负荷评价。采用地表水环境质量标准（GB3838-2002）三类水质标准对海河流域2007年农业非点源污染入河量进行等标负荷评价,结果表明:总氮是农业非点源污染最主要的污染物,约占一半;其次是总磷,约占1/4。农业非点源污染主要来自于畜禽养殖污染,占八成以上,其次是农村生活15.7%,种植业源仅占3.3%。海河流域农业非点源污染地域差异较大,污染最严重的是德州市,其次是唐山市和承德市。环境资源的公共物品属性决定了控制农业非点源污染必须由政府主导,公众广泛参与。从中国的情况来看,非点源污染得不到有效控制,除了资金和技术的制约外,更重要的是缺乏健全的法律制度和完善的管理体系。海河流域要重点抓好畜禽养殖污染的控制,大力推广生态畜牧业。积极推进“农村清洁工程”,改善农村生活条件。更多还原

【Abstract】 China is in severe shortage of water resources in terms of per capita amount which is less than 1/3 of the world average. Meanwhile water quality is degrading since the reform and opening up due to swift and vigorous economic development. According to < China’s Environmental Aspect Communique 2009>, China’s surface water quality was far from satisfactory. The Seven Water Systems were lightly polluted in general, in which Haihe Basin was heavily polluted with 66% of rivers examined less than theⅢlevel of Environmental Quality Standards for Surface Water （GB 3838-2002）.Studies have showed that agricultural nonpoint source （NPS） pollution is one of the main contributors to water quality impairments in China. According to < China’s First General Survey Communiquéon Pollution Sources > （2009）, COD, TN, TP discharged from agricultural sources accounted for 43.7%, 57.2% and 67.4% of national total emissions respectively in 2007.For the first time, this paper studied Haihe Basin agricultural NPS loads and estimate its contribution to water quality. The research findings will help the government to define priority industries and critical areas for water quality control, and to distribute abatement targets between point source （PS） and NPS pollution.This paper set up a new methodology on estimating agricultural NPS loads on macro-scale watershed. It is named as“Three-Dimensional Unit load Method”with following features: （1） The whole basin is divided into smaller units for estimation on three levels---the whole basin, water resource district/ province and county according to river system and landform; （2） Agricultural NPS is divided into three sources---crop farming, animal breeding and rural life; （3） Agricultural NPS is divided into three phases---input, export and deliver to rivers according to polluting formation process.The main findings of this paper are as follows:1.Total Agricultural NPS LoadsIn Haihe Basin in 2007, Agricultural NPS input loads were COD 774.1x10⁴ t, TP 192.0 x10⁴ t, TN 459.1x10⁴ t, NH₄⁺-N 67.8x10⁴ t; export loads were COD 239.4x10⁴ t, TP 4.5x10⁴ t, TN 56.8x10⁴ t, NH₄⁺-N 6.2x10⁴ t; delivered-to-rivers loads were COD 68.0x10⁴ t, TP 0.9 x10⁴ t, TN 8.6x10⁴ t, NH₄⁺-N 1.1x10⁴ t. Tuhaimajiahe Plain/Hebei Province accounted for the largest proportion of agricultural NPS loads in Haihe Basin.2.Contribution of NPS to Water QualityMeasured by multi-year mean amount of surface water resources （1956～2000 hydrologic series）, the pollutant loads added to warters by agricultural NPS were COD 31.5 mg·L^-1, TP 0.4 mg·L^-1, TN 4.0 mg·L^-1, NH₄⁺-N 0.5 mg·L^-1 in Haihe Bain in 2007. Compared with theⅢlevel standard of <Environmental Quality Standard for Surface Water> （ GB3838-2002）, except for NH₄⁺-N, all others pollutants surpassed the standard by 1.6 times for COD, 2.0 times for TP, 4.0 times for TN.In general, PS contributed the most part of COD （62.0%） and NH₄⁺-N （91.5%）, while NPS contributed the most part of TP （60.2%） and TN （58.7%） in river pollution. Based on the fact that only COD and NH₄⁺-N were included in the pollutants list which surpassed the surface water quality standard instead of TP and TN, We would conclude that PS other than NPS was the leading source of river pollution in Haihe Basin.3.Critical Pollutants/Sources/Areas of Agricultural NPSDividing agricultural NPS delivered-to-river loads by theⅢlevel Surface water quality Standard, this paper found that in Haihe Basin （1） TN was the main pollutants contributed by agricultural NPS which accounted for half of the total loads; （2） Agricultural NPS loads mainly derived from livestock waste which accounted for 81% of the total loads; （3） Agricultural NPS loads varied greatly in different regions with Dezhou/ Longhua were the most severely polluted city/county.The government should play a leading role in environmental protection because of the publicity and externality of rural environment while participated widely by the public. Judging the situation in China in environmental protection practices, it was not only insufficient funds or technologies but also poor management including imperfect environmental legal and managerial system that had resulted in ineffective water quality prevention and control. The government should amend current law system to make it more complete and exercisable, strengthen the authority of watershed administrative organization and enhance the coordination and cooperation between all related administrative parties. Meanwhile, the government also needs to expand money input in all kinds of rural eco-friendly activities by ecological compensation and other means of subsidy. The focus of government environmental management and control lies in livestock breeding, which contributes most part of agricultural NPS pollution. In this regard, eco-breeding should be highly encouraged. Meanwhile rural living conditions need to be improved as well.“Rural Cleaning Project”is a good choice in building a New Socialist Countryside.更多还原