Modelling Cryptosporidium oocysts transport in small ungauged agricultural catchments.
Modelling Cryptosporidium oocysts transport in small ungauged agricultural catchments.
复制标题
DOI：
10.1016/j.watres.2011.04.013
复制
发表时间：
2011-06
期刊：
影响因子：
12.8
通讯作者：
Jia-liang Tang;S. McDonald;X. Peng;S. Samadder;T. Murphy;N. Holden
中科院分区：
文献类型：
--
作者：
Jia-liang Tang;S. McDonald;X. Peng;S. Samadder;T. Murphy;N. Holden
隐孢子虫是一种环境强大的病原体，已在世界范围内引起严重的水传播疾病爆发。人类饮用水中人畜共患的小隐孢子虫卵囊的主要来源很可能来自农场动物，通过以水为主要运输媒介的集水路径。绝大多数小型农业流域都没有测量，因此很难使用过程模型来预测和理解调节农业区地表水污染风险的机制和活动。在本研究中，使用爱尔兰的两个未测量的农业流域，使用 SWAT2005 每天模拟隐孢子虫卵囊的运输，并参考相邻流域测量站的参考数据。结果表明，SWAT2005 可以每月模拟水流，预测与观测之间具有良好的一致性（R2 从 0.94 到 0.83，E（效率）从 0.92 到 0.66），但隐孢子虫卵囊浓度结果不太可靠（R2 从 0.20 到 0.37，P < 0.05；E 较差 -0.37 到 -2.57）。使用独立参数扰动进行的敏感性分析表明，温度是调节研究流域中卵囊运输的最重要参数，并且相对于水径流事件发生的粪肥施用时机至关重要。结果还表明，放牧管理对预测的卵囊运输影响不大，而施有粪肥的田地是研究流域微生物污染的关键源区。结论是，所提出的方法可用于帮助了解水源性隐孢子虫病暴发的流行病学，并改善流域管理，以保障公众健康的安全。
Cryptosporidium is an environmentally robust pathogen that has caused severe waterborne disease outbreaks worldwide. The main source of zoonotic Cryptosporidium parvum oocysts in human drinking water is likely to be from farm animals via catchment pathways with water as the main transport vector. The vast majority of small agricultural catchments are ungauged therefore it is difficult to use a process model to predict and understand the mechanisms and activities that regulate the risk of surface water contamination from agricultural areas. For this study, two ungauged agricultural catchments in Ireland were used to model Cryptosporidium oocyst transport using SWAT2005 on a daily basis with reference data from adjacent catchment gauging stations. The results indicated that SWAT2005 could simulate stream flow with good agreement between prediction and observation on a monthly basis (R2from 0.94 to 0.83 and E (efficiency) from 0.92 to 0.66), but Cryptosporidium oocyst concentration results were less reliable (R2from 0.20 to 0.37, P < 0.05; with poor E −0.37 to −2.57). A sensitivity analysis using independent parameter perturbation indicated that temperature was the most important parameter regulating oocyst transport in the study catchments and that the timing of manure application relative to the occurrence of water runoff event was critical. The results also showed that grazing management had little influence on predicted oocyst transport while fields fertilized with manure were the key critical source areas for microbial contaminations in the study catchments. It was concluded that the approach presented could be used to assist with understanding the epidemiology of waterborne cryptosporidiosis outbreaks and to improve catchment management for the safety of the general public health.