Characteristics of shallow groundwater and its influences in plain river network region of Taihu Basin

In view of the important role in the maintenance of regional ecologic function, the spatio-temporal characteristics of shallow groundwater burial depth (SGBD) and its influential factors were studied based on the daily SGBD data (from 2005 to 2015) and regional precipitation, water level and evaporation data (from 2005 to 2014) in Taihu Basin. The results indicated that: The shallow groundwater in Suzhou showed a flow direction from north to south, and from west to east, which is mainly affected by regional topographic conditions. The regional SGBD showed a slightly reduction in annual and flood season scale, while increase in non-flood seasons. The change processes varied among regions. The variation of SGBD is significantly related to the amount and frequency of different precipitation ranks in non-flood seasons, and affected by surface water. Moreover, the diversion and drainage, and underlying surface change were also the influential variables. While these features were opposite in flood seasons. The variation of SGBD often lags 1 to 2 days to precipitation. The characterization of shallow groundwater could be divided to four types, such as the agricultural, watery, urbanized and low mountainous regions, through the overlay of the influential variables, such as geomorphologic conditions, land use types, densities of rivers and lakes, and shallow groundwater burial depth. © 2018 by Journal of Lake Sciences.