In the study area groundwater and surface water

The study area is located at Shahu County, Jianghan Plain of central China; Jianghan Plain is an alluvial plain with subtropical monsoon climate and abundant water resources, which make it one of the nation\'s major regions of agriculture and aquaculture production. The study area is located at the middle region of the Jianghan Plain and surrounded by four rivers and rivulets: the Tongshun River (TSR) and Dongjing River (DJR), both as tributaries of the Yangtze River, are two main perennial rivers flowing from west to east all the year; the Kuige Rivulet (KGR) and Lvfeng Rivulet (LFR) are two seasonal rivers. Water in LFR and most part of KGR are generally stagnant, and water in KGR would flow to TSR during rainfall BMS 191011 towards the major conjunction between TSR and KGR (at the northeast corner of Fig. 1.). The water table of the study area is electron transport commonly 0.5–3.5 m b.l.s. with low hydraulic gradients, and groundwater generally flows from south to north, under the impact of strong interactions between groundwater and surface water (Gan et al., 2014) (Fig. 1.). The main crops in the county are paddy, cotton, peanut and sugarcane, which are irrigated by groundwater. Both manure and fertilizer are used for crop growth. Most of the residents in Shahu County are located along rivers or rivulets, and there is no centralized sewage treatment facility in the area. Domestic sewage and industrial wastewater are drained to the environment, the potential pollutants would either infiltrate into the aquifers or migrate into the rivers and rivulets.