Seasonal Variations in Groundwater Level and Salinity in Coastal Plain of Eastern China Influenced by Climate

Abstract

The coastline of China is approximately 18,000 km long. In most coastal cities, seawater intrusion is a serious threat to groundwater resources. Nine shallow monitoring wells were constructed to study the dynamics of shallow groundwater level and salinity in the coastal plain region of Jiangsu province, China. Results showed that precipitation, evaporation, and river stage affected the groundwater level in our study area. Positive correlations were observed among the groundwater level, precipitation, and river stage; then negative correlation existed between the groundwater level and evaporation. The influencing factors on the groundwater level were in the order precipitation > river stage > evaporation. Sufficient precipitation during the wet season diluted the groundwater salinity. After the dilution, between two continuous precipitation events, the groundwater salinity increased as the groundwater level decreased. During the dry season, the groundwater salinity rapidly increased and reached its peak in December. The groundwater salinity in December was 23 times higher than that in July. The groundwater level and salinity in this study were generally associated with the season. Climate factors led to fluctuation of groundwater levels and salinity during the wet season, and seawater intrusion increased the groundwater salinity during the dry season.

Seasonal variation of hydrochemical characteristics of open-pit groundwater near a closed metalliferous mine in O’Kiep, Namaqualand Region, South Africa

“…The groundwater has a distinct Na-Cl character, mainly due to the geochemical composition of the crystalline rocks and alluvium from the Namaqua Metamorphic Complex (Titus 2002;Van Wyk et al 2012;Braune and Xu 2010;Xu and Braune 2009) which primarily hosts groundwater in the study area. The Na-Cl dominant rainfall, dissolution and leaching of evaporates can further augment the salinity of the groundwater (Van Wyk et al 2012).…”

Contamination of Nitrate in Groundwater and Evaluation of Health Risk in Bachok, Kelantan: A Cross-Sectional Study

“…High conductivity of well water in the non-agricultural area was possibly due to the location of this area which situated near to coastal area. The addition of salt water from the coastal which is often mixed with groundwater greatly increases the conductivity (Yan et al, 2015).…”

“…Other factors such as precipitation, evaporation, mineralogy, type of aquifers and seawater intrusion also may influence the salinity level in the water (Yan et al, 2015).…”

“…Therefore, the presence of nitrate in groundwater can affect the conductivity. Besides, because of nitrate is dissolved inorganic solids, nitrate also has correlation with TDS and salinity (Igboekwe et al, 2011;Annapoorani et al, 2014;Yan et al, 2015).…”

Key technologies and equipment for contaminated surface/groundwater environment in the rural river network area of China: integrated remediation

“…It should be noted that the boundary zone of surface and subsurface is a complex environmental system where the mass (including pollutant) transformation occurs actively because of the active exchange of surface water and groundwater [14]. This situation is especially significant in the plain river network area in China where the underground water tables are generally high at − 1 to − 3 m [15]. Surface water bodies, such as streams, lakes, and reservoirs, frequently interact with groundwater, and their interaction is of great importance in the hydrologic processes of river basins [16].…”