a b s t r a c tFecal coliform bacteria are a key indicator of human health risks; however, the spatiotemporal variability and key influencing factors of river fecal coliform have yet to be explored in a rural-suburban-urban watershed with multiple land uses. In this study, the fecal coliform concentrations in 21 river sections were monitored for 20 months, and 441 samples were analyzed. Multivariable regressions were used to evaluate the spatiotemporal dynamics of fecal coliform. The results showed that spatial differences were mainly dominated by urbanization level, and environmental factors could explain the temporal dynamics of fecal coliform in different urban patterns except in areas with high urbanization levels. Reducing suspended solids is a direct way to manage fecal coliform in the Beiyun River when the natural factors are difficulty to change, such as temperature and solar radiation. The export of fecal coliform from urban areas showed a quick and sensitive response to rainfall events and increased dozens of times in the short term. Landscape patterns, such as the fragmentation of impervious surfaces and the overall landscape, were identified as key factors influencing urban non-point source bacteria. The results obtained from this study will provide insight into the management of river fecal pollution.

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a b s t r a c tRoof runoff pollution has been given considerable attention to ensure the safety of roof rainwater utilization. A residential roof catchment located in Handan, China, was selected as a study site. The water quality of roof runoff was analyzed at 15 storm events during 2014-2016. The median concentrations of chemical oxygen demand (COD), ammonia nitrogen, total nitrogen, total phosphorus and sulphane are 104, 8.53, 10.60, 0.21 and 14.31 mg/L, respectively; these values all exceed the class V of environmental quality standards for surface water in China. A strong linear correlation is established between COD and other pollutants. All the Pearson's coefficients (r) are more than 0.8. COD could be considered surrogates for other pollutants. During storm events, the concentration change of runoff pollutants could be fitted well by the exponential function. The selected storm events present the first flush effect in varying degrees. Approximately 80% of the pollutant load is transported in the first 36%, 53%, 57%, 26% and 38% of the volume for five storm events. The first flush effect is evidently related with rainfall depth and antecedent dry days. Furthermore, water quality depth (WQD) can be used as a definitive parameter for runoff pollution control. WQD presents different values to reach diverse stormwater management targets.

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