Evaluation of climate change and land-use impacts on groundwater dynamics in the bari doab canal system
摘要
Globally, groundwater depletion has grown to be a serious issue, as land and water resources have been gravely exhausted due to the rising population's desire for food and water. The current research evaluated the decline in groundwater caused by land use and climate change in the Bari Doab Canal, Pakistan, utilizing the latest Coupled Model Intercomparison Project (CMIP6) of the global climate model (GCM). Sixteen years of data (2005–2020) from the Punjab Irrigation Department were used to generate IDW interpolation maps within the ArcGIS environment. The Penman–Monteith equation in the CROPWAT model was used to calculate crop water requirements. Cellular Automata Markov Chain model was used to create LULC maps of 2030, 2060, and 2100 by analyzing the changes based on Landsat (7 and 8) satellite imagery gathered in 2000, 2010, and 2020. Groundwater extraction was estimated through the deficit of effective rainfall and net canal water use from evapotranspiration after compensating for soil moisture storage changes. GCM projected rainfall and temperature under two Shared Socioeconomic Pathways (SSPs), SSP2 and SSP5, were downscaled using the CMhyd model till the end of the twenty-first century. The precipitation, maximum and minimum temperatures, and crop water requirements were anticipated to increase by downscaled projections of a selected model (MPI-ESM1-2-HR) till the end of the twenty-first century (2015–2100) compared to the baseline period (1981–2020). The water table dropped by 0.62 m annually over 16 years (2005–2020). Urbanization increased steadily from 2000 to 2100, while all other categories, water, dense vegetation, vegetation, and barren land experienced a decline. The Visual MODFLOW model outcomes demonstrated the detrimental effects of the expected changes in land use and climate on the groundwater in Bari Doab. This study supports the development of appropriate adaptation measures by policymakers and stakeholders to mitigate the detrimental impacts of climate and land use change on groundwater dynamics.