ASSESSING WATER LEVEL VARIABILITY IN THE ZHAIYK (URAL) RIVER BASIN USING GRACE SATELLITE GRAVIMETRY AND HYDROLOGICAL OBSERVATIONS. JGEM [Internet]. 2025 Jun. 20 [cited 2026 Jul. 13];77(2). Available from: https://bulletin-geography.kaznu.kz/index.php/1-geo/article/view/1534