Assessing seasonal and long-term changes in groundwater quality due to over-abstraction using geostatistical techniques

• Published in: Environmental earth sciences 2019-07, Vol.78 (13), p.1-12, Article 386
• Main Authors: Farid, Hafiz Umar, Ahmad, Ijaz, Anjum, Muhammad Naveed, Khan, Zahid Mahmood, Iqbal, Muhammad Mazhar, Shakoor, Aamir, Mubeen, Muhammad
• Format: Article
• Language: English
• Subjects: Biogeosciences; Climate change; Earth and Environmental Science; Earth Sciences; Electrical conductivity; Electrical resistivity; Environmental Science and Engineering; Future climates; Geochemistry; Geology; Geostatistics; Groundwater; Groundwater data; Groundwater quality; Groundwater table; Hydrology/Water Resources; Long-term changes; Monitoring; Monsoons; Original Article; Quality; Seasons; Sodium; Spatial distribution; Temporal variability; Temporal variations; Terrestrial Pollution; Trends; Water availability; Water quality; Water table; Wind
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-019-8373-2

Future climate change and the temporal variability of water availability may cause the deterioration of groundwater quality and increase depths to water tables. In this study, groundwater quality data of 347 monitoring sites from 2003 to 2016 from a region in Pakistan were used to analyze the spatiotemporal variability in different water quality parameters using the Mann–Kendall and Sen’s slope estimator tests. The results indicated a significant increasing trend (SIT) at 23% sites in pre-SAR (sodium adsorption ratio during the pre-monsoon season) and at 22% sites in pre-EC (electrical conductivity during the pre-monsoon season) over the entire study period. The spatial distribution modeling of groundwater quality trends indicated that a significant increasing trend was observed in EC at most of the monitoring sites during the pre-monsoon season ( α  = 0.05). The area with significant increasing trend of groundwater EC and SAR values increased during the pre-monsoon season and decreased during the post-monsoon season. A continuous significant increasing trend in EC and SAR was observed in the northern part of the study area during the period 2003–2016. This trend indicates that excessive groundwater abstraction in the area is causing adverse impacts on groundwater quality, and that management measures need to be urgently implemented to limit further degradation of groundwater quality.