Groundwater salinity in the Horn of Africa: Spatial prediction modeling and estimated people at risk

Groundwater Salinity Across India: Predicting Occurrences and Controls by Field-Observations and Machine Learning Modeling

“…In the northwest and southeast coast, overabstraction has been reported to cause a decline in groundwater , (Figure S7), subsequently increasing seawater ingress like other coastal areas globally , (Figure ). These coastal areas were observed to have low-lying flat areas that can promote further seawater ingress , (Figures and S7) and also corresponds with previous studies from the coastal areas of Africa and Iran. , Significant urban areas on the southeast coast, such as Chennai, Puducherry, and Vishakhapatnam, were also predicted with elevated salinity here (Figure a). A small stretch of the south-central Gujarat coast exhibited low probabilities (Figures a and S7), presumably due to the higher elevation, agreeing to prior reports , (see Text S5).…”

“…Massive irrigational groundwater abstractions can also elevate salinity in the northwest and southeast parts , (Figures a and S7). Declined groundwater changes hydraulic equilibrium, allowing deep saline groundwater to interact with fresh groundwater. , Decrease in groundwater level has also been identified as an important factor controlling groundwater salinity in the Horn of Africa . High irrigational return flows and fertilizer use in the highly agrarian northwest and southeast of India can also raise salinity , (Figure S1).…”

“…51,119 Decrease in groundwater level has also been identified as an important factor controlling groundwater salinity in the Horn of Africa. 120 High irrigational return flows and fertilizer use in the highly agrarian northwest and southeast of India can also raise salinity 11,37 (Figure S1). Also, most Indian saltwater lakes are in the northwest and southeast, which can also leach highly saline water 102,121 (Figure S7).…”