Effects of river sinuosity on the self-purification capacity of the Shiwuli River, China

Abstract

This study focused on the correlation between river sinuosity and self-purification capacity, using the Shiwuli River in Hefei, China, as a case. Through field monitoring, the reduction rate of each pollutant per unit length of river reach and its correlation with the corresponding sinuosity were analysed. The results show that river sinuosity has different degrees of positive correlation with the growth rate of dissolved oxygen (DO) and the reduction rates of total nitrogen (TN), ammonia nitrogen (NH3-N) and total phosphorus (TP). River sinuosity needs to be above 1.42 to ensure the river's basic self-purification capability. We also discuss the mechanism of river sinuosity on water body self-purification and propose the increase in river sinuosity to improve the river's capacity to purify water from pollutants. This measure could enhance the growth rate of DO, the longitudinal hyporheic exchange flow, and the action time of other basic self-purification factors of the river. This study could help scientific decision-making in river reconstruction planning in the process of urbanization in the middle and lower reaches of the Yangtze River in China.

Diatom Taxonomic Composition as a Biological Indicator of the Ecological Health and Status of a River Basin under Agricultural Influence

“…Rivers can recover the pollutant load within certain limits [42]. The TSI change at station 8 suggested that limitation of river self-purification ability to diatom diversity cannot be ignored in agricultural influenced rivers during ice cover [43]. Thus, the chemical factors, self-purification ability and velocity monitor in further river regulations during ice cover is necessary.…”

An investigation into the impact of nine catchment characteristics on the accuracy of two phosphorus load apportionment models

“…This behaviour will mean that true point source apportionment levels are masked as the rise in Q and P would be attributed to diffuse source by the LAM assumptions (Jarvie et al, 2012), whilst increasing levels of P retention reduce the BM applicability. Furthermore, climate, chemical state and river geomorphological characteristics will impact the variability of retention rates and observed patterns (McDowell et al, 2017;Omari et al, 2019;Xiao et al, 2019). This may further conspire to cause model output variability as the Q-P relationships that the LAM rely upon are being complicated.…”

Assessment of river morphology based on changes in land use and land cover and the spatial and temporal variation of meandering parameters of the barak river

“…Field data and numerical models estimated meandering and its morphological changes (Xiao et al 2019). Unfortunately, most alluvial river lengths are unreachable by field technique.…”