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Hydrological regimes influence an aquatic ecosystem's biotic composition, structure, and functioning. But construction of dams or anthropogenic activities substantially alter the hydrologic regimes. In this study, we used a method named as the "Indicators of Hydrologic Alteration" to examine the degree of hydrologic alteration at seven flow gauge stations in the Mangla watershed. The assessment of alteration is carried out according to the Range of Variability (RVA). This method relies on analyzing hydrologic data obtained from existing measurement points (e.g., stream gauges) within an ecosystem or model-generated data. We used 33 parameters categorized into 5 groups based on magnitude, duration, frequency, timing, and rate of change to characterize hydrologic variation within a year statistically. We then examine the hydrologic perturbations by comparing the measure of central tendency and dispersion for each parameter between the "pre-impact (1967–1994)" and "post-impact (1995–2014)" periods. The results show that within the Mangla watershed, the high alteration was noted in the magnitude of monthly flows and extreme flows at Azad Pattan, Gari Habibullah, Palote and at Muzafarabad stations. The flow at Domel and Kohala stations are found in low hydrological alteration among all groups of indicators. The study indicates that Neelum Basin at Muzaffarabad has significantly high alteration with maximum negative values. On the other hand, a high frequency of alteration observed in the monthly flows and extreme water conditions. Overall, a moderate alteration is observed in the whole watershed, which may produce adverse effects on the aquatic ecosystem of the Mangla watershed. [ABSTRACT FROM AUTHOR]

Groundwater represents 98% of the world's freshwater resources. These resources have been strongly impacted by the increases in temperature and in the variation in precipitation. Despite many advances, the relationship between climate change and the dynamics of aquifer recharge is still poorly understood. This study includes an analysis of 211 papers using the biblioshiny function in the bibliometric R Package. Additionally, specific papers were selected to identify limits, trends, and negative and positive impacts. The results indicated an average growth of 14.38% and a significant increase in research from 2009. In total, 52 countries have undertaken studies in this field, just over 26% of the total number of countries. In the papers examined, the worst projections related to reductions in recharge were identified for arid and desert areas; the highest recharges were identified in the northern regions and in areas at high altitudes, where recharge capacity is maintained or increases due to rapid snow and glacial melting resulting from temperature increases. Despite the advances achieved, more studies should be extended to analyse groundwater assessment at other latitudes to reach a complete and comprehensive understanding. This understanding should be one of the priorities for water among governments and the scientific community in order to safeguard this precious resource. [ABSTRACT FROM AUTHOR]