Study of temporal changes in the hydrographic network of small mountain rivers in the Ile Alatau, Kazakhstan

Abstract The article presents the outcomes of an assessment of hydrographic network changes within the Almaty city, utilizing geographic information system (GIS) technology and Earth remote sensing data. Two gauge stations were selected along the main rivers within the Almaty city. To identify distinctive alterations in these rivers, hydrological data series encompassing the maximum runoff from 1970 to 2021 were collected and subjected to statistical analysis. Differential integral curves were constructed to pinpoint periods corresponding to peak and trough runoff levels. For each of these identified periods, the processing of satellite imagery allowed for the computation of meandering coefficients for the river channels. Additionally, refinements were made to the slope values of the rivers during these same timeframes, and connectivity graphs were established to elucidate the relationship between slope and liquid runoff for each period. The analysis encompassed an assessment of the impact of anthropogenic factors on both artificial and natural bodies of water while also considering shifts in the boundaries of the Almaty city. The findings derived from this study have practical applications in the planning and design of water supply systems and in the implementation of measures aimed at mitigating the adverse effects of anthropogenic factors on water bodies.