题名基于SWAT 构建大宁河流域隐孢子虫归趋模型
作者刘伟
学位类别硕士
答辩日期2016-05
授予单位中国科学院研究生院
授予地点北京
导师安伟
关键词隐孢子虫 Cryptosporidium 归趋模型 SWAT SWAT the fate and transport model 产流产沙 Runoff and sediment yield 大宁河流域 Daning River Watershed 病原微生物 Pathogen.
其他题名Modelling the Fate and Transport of Cryptosporidium in Daning River Watershed Based on SWAT
学位专业环境科学
中文摘要      隐孢子虫是一种水介传播的病原微生物,能够耐氯、且能够“人畜共患”,对人群公共健康形成了威胁。隐孢子虫在我国地表水中广泛存在,构建针对我国实际情况的隐孢子虫流域归趋模型,有助于我国地表水隐孢子虫污染风险评估及提出污染源控减对策,对我国控制隐孢子虫病的感染和暴发有重要意义。
      本研究以隐孢子虫污染较严重的三峡库区大宁河流域为例,基于SWAT,结合当地流域水文特点、畜牧业、农业和污水治理情况,构建了流域内的隐孢子虫归趋模型, 取得如下主要成果:
      1.构建了大宁河流域SWAT 产流产沙模型,并基于SWATCUP 工具中的SUFI-2 方法,以2008-2010 年为校正期、2011-2013 年为验证期对模型进行了参数敏感性分析、校正、验证和不确定性分析。结果显示,构建的大宁河流域SWAT 产流产沙模型的月产流模拟效果非常好(校正期和验证期NS 分别达0.93 和0.92),产沙模拟效果好(校正期和验证期NS 分别达0.74 和0.72),且不确定性满足要求,可在该模型的基础上进一步模拟病原微生物在流域里的运输和传播。
      2.构建了大宁河流域隐孢子虫归趋模型。在SWAT产流产沙模型的基础上,结合当地流域畜牧业、农业和污水治理情况,构建了隐孢子虫归趋模型,模型模拟结果显示大宁河流域多年平均隐孢子虫浓度值为7.21个/10L,各子流域出口多年平均隐孢子虫浓度范围为1.05~15.59个/10L,与文献中相同时期的实测调查结果非常接近,初步验证本研究所构建的隐孢子虫归趋模型对大宁河流域隐孢子虫的浓度模拟预测结果是合理的。
      3.探讨了流域里的隐孢子虫浓度水平的时空分布,不同污染源在各个月份对整个流域和流域出口的隐孢子虫浓度的贡献率以及径流量和施肥对流域水体隐孢子虫浓度高低的影响。对模型模拟预测结果进行分析,结果表明:1)子流域7、8、21 的多年平均隐孢子虫浓度最低,子流域4、10、11 的多年平均隐孢子虫浓度最高,初步归因于不同子流域城镇人口密度和耕地所占面积比的差异。2)流域出口和整个流域的平均隐孢子虫浓度在全年中4-6 月份浓度最高,8-9 月份浓度最低,在5 月份达到峰值,分别为12.95 个/10L 和13.50 个/10L。3)在1-3月、8-9 月、12 月,点源污染源贡献的隐孢子虫浓度明显大于非点源污染源;在5-7 月和11 月,非点源污染源贡献的隐孢子虫浓度明显大于点源污染源;在4 月和10 月,点源污染源和非点源污染源贡献的隐孢子虫浓度相当。4)隐孢子虫浓度受径流量和施肥耦合作用的影响,要远高于独立作用的影响。
      4.利用构建好的大宁河流域隐孢子虫归趋模型进行了流域水体隐孢子虫浓度削减方案情景分析,并提出了两种比较有效的削减方案。削减方案1:在流域内全面建设城镇生活污水处理厂,使所有城镇生活污水经过污水处理厂处理后再排放。削减方案2:将50%的农村居民粪便和畜禽粪便堆肥满56 天后再用于施肥。模型模拟结果表明:削减方案1 能大幅度的削减水体全年每个月的隐孢子虫浓度,削减率最高达83%;而削减方案2 则能更大程度的削减全年峰值时段(5-6 月)的水体隐孢子虫浓度。联合使用削减方案1 和削减方案2,其削减率为两种削减方案削减率之和,削减效果更加显著。
英文摘要      Cryptosporidium is a waterborne pathogen. Because of the characteristics of extreme resistance against chemical disinfection and zoonosis infection,Cryptosporidium is a great threat for human health. Cryptosporidium was widely distributed in the surface water in China. Modelling the fate and transport of Cryptosporidium in watershed would do contribution to the risk assessment of Cryptosporidium pollution and putting forward pollution control countermeasures.
      Daning River Watershed which was seriously polluted by Cryptosporidium was selected as the research area. With the information and data about animal husbandry,agriculture and the situation about wastewater treatment in Daning River watershed, the fate and transport of Cryptosporidium was modelled based on SWAT. The main results were summarized as follows:
      1. A model simulating runoff and sediment yield of Daning River watershed was constructed based on SWAT, in which the calibration period is from 2008 to 2010 and the validation period is from 2011 to 2013. In further, parameters sensitivity, calibration,validation and uncertainty analysis of the model were conducted. The constructed SWAT model could be well used for runoff simulation (NS=0.93 and 0.92 in calibration period and validation period respectively) and sediment yield simulation (NS=0.74 and 0.72 in calibration period and validation period respectively) in Daning River watershed and uncertainty of the model can meet the requirements. In further, the model could be used to model the fate and transport of Cryptosporidium in Daning River watershed.
       2. A model simulating the fate and transport of Cryptosporidium was constructed based on SWAT. The modelling result showed that the mean annual Cryptosporidium concentration of the whole watershed was 7.21 oocysts/10L, the range was1.05~15.59 oocysts/10L, which was very close to the result from literatures in which the oocysts concentration in Daning River watershed was measured in the same research period. Therefore, the constructed model was initially considered as reasonable.
       3. Oocysts concentration level in the basin over time and space, the contribution of different pollution sources on oocysts concentration in the outlet and watershed of every month, and the influence of runoff and fertilization on the oocysts concentration in the watershed were discussed and explored. The model result indicated that: 1) The mean annual oocysts concentration in subbasins 7,8,21 were highest while in subbasins 4, 10, 11 were lowest. This may due to the difference of urban population density and the ratio of agricultural land. 2) The mean annual oocysts concentration in the whole watershed and in the outlet were highest during April to June compared to other period in the whole year and achieved the peak in May, which was 13.50 oocysts/10L and 12.95 oocyss/10L,respectively. 3) From January to March, August to September and in December, the contribution to the oocysts concentration from point source pollution was higher than the contribution from nonpoint source pollution. To the contrary, from May to July, and in November, the contribution from nonpoint source pollution was higher than point source pollution. In April and October, the contribution from nonpoint source pollution and point source pollution were considerable. 4) The couple strength of runoff and fertilization was much stronger than the individual role of runoff or fertilization.
4. Oocysts concentration abatement scenarios were analyzed based on the constructed model and two effective abatement measures were put forward.Scenario1: building wastewater treatment plants in Daning River watershed in an all-round manner,so that all the urban domestic sewage can be treated by wastewater treatment plants before being discharged to Daning River. Scenario2:50% of the feces from rural citizens and livestock were composted up to 56 days before being used as manure. Scenario1 could sharply reduce oocysts concentration every month throughout the year and the highest abatement rate was 83%, while scenario 2 could reduce more oocysts concentration during the peak time (May and June). With combination of scenario 1 and scenario 2, the abatement effect was more significant, of which the abatement rate was the sum of the two scenarios.
内容类型学位论文
源URL[http://ir.rcees.ac.cn/handle/311016/36899]  
专题生态环境研究中心_环境水质学国家重点实验室
推荐引用方式
GB/T 7714
刘伟. 基于SWAT 构建大宁河流域隐孢子虫归趋模型[D]. 北京. 中国科学院研究生院. 2016.
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