Groundwater Recharge (GR) is a crucial part of sustainability studies since it is one of the key factors responsible for making the groundwater resource renewable. An optimum strategy for responding to water level decline is artificial groundwater recharge. Artificial groundwater recharge projects are limited by cost, and the effective area is less. The role of natural factors for groundwater recharge is well defined and recognized in arid regions, whereas it’s challenging for humid areas. The current study’s main aim is to understand the contribution of the bio-geophysical aspect to groundwater recharge in the subtropical monsoon state of Uttar Pradesh in the Gangetic Plain. However, recharging is also one of the least understood processes because it changes over time and space and is challenging to quantify directly for a larger area. This research applied the ‘water and energy transfer among bare soil, vegetation, and atmosphere (WetSpass)’ model to estimate direct natural GR for Uttar Pradesh. The model’s output and its regression processes with climate, slope, soil type, and vegetation give a comprehensive understanding of natural controlling factors. Among the aforementioned controlling factors, though climate sharpens recharge dominantly, vegetation has shown a significant role in some areas of the state. In contrast to the prevailing view, vegetation cover can enhance groundwater recharge in the state. Thus, planting, and various tree management options, including groundwater-feeding species as a secondary plantation in cropland, can improve groundwater resources.

Mohammad Taqi Daqiq

and 3 more

Mohammad Taqi Daqiq 1, Ravi Sharma1,*, Anuradha Karunakalage 1 and Suresh Kannaujiya 21 Indian Institute of Technology Roorkee, Roorkee, Uttarakhand - 247667, India ([email protected])2 Indian Institute of Remote Sensing, Indian Space Research Organization, Dehradun, Uttarakhand - 248001, India (e-mail: [email protected])*Corresponding author: ([email protected])The country of Afghanistan over the last two decades, has faced an acute shortage of the precious groundwater resource. Some of the significant reasons are hydroclimatic or anthropogenic, but the very definite one that tops it all is the ignorance and the mismanagement of the surface water system. The monthly groundwater storage variation has been calculated from April 2002 to October 2021 using the Gravity Recovery and Climate Experiment (GRACE) dataset for five major river basins of Afghanistan, including Kabul, Amu Darya, Northern, Hari Rud and Helmand river basins. The seasonal groundwater storage anomaly reveals a comparatively gentle negative trend in the Amu Darya and Northern rivers basins than the rest. Consequently, the trends estimated in Kabul, Hari Rud and Helmand basins are dramatically decreasing. Hydroclimatic influence for groundwater storage was compared with the Standardized Precipitation Index (SPI-12 months). Though the SPI values have shown a wet period from 2013 to 2017, the groundwater is declining continuously. Analysis of the Groundwater Storage Abstraction (GWSabs) has been carried out for the entire country. The estimated GWSabs trend (2003-2021) gives a maximum value for the Northeast and Southwest parts of the country. One of the hidden crises of extensive groundwater consumption is land subsidence. The study focused on the evolution of the vadose zone, resulting in land deformation in Kabul City. The resultant land displacement is determined using Sentinel-1 data in the most populated city of Afghanistan (Kabul). The time-series analysis shows two-phase of displacement. In phase I (2015-2017), there is a common gentle trend (-20.66 mm/year in Upper Kabul aquifer and -18.54 mm/year in Lower Kabul aquifer), but in Phase II (2018-2020), a high negative trend (-151.34 mm/year in Upper Kabul and -145.32 mm/year in Lower Kabul) was observed. The vertical displacement was estimated at a maximum value of -202 mm for Kabul City between June 2016 and August 2020. Overall, the entire country is experiencing a severe groundwater decline, but the most dominant ones are the southern and western parts of Afghanistan, causing the not-so-obvious crisis such as land subsidence. This study states that strong policy and regulations change is required to sustain groundwater resources in the country.Keywords: GRACE; InSAR; Land Deformation; Groundwater abstraction (GWSabs); GWSD; △GWSPresented to the AGU Fall Meeting-22 on Dec 16, 2022Paper ID: GC52I-0251Abstract ID: 1105129