Hydrological regime of the Chorniava River in the system of integrated water resources management of the transboundary Prut River basin

Abstract

The article investigates the contemporary hydrological regime of the Chorniava River, an important left-bank tributary of the Prut River, within the framework of integrated water resources management in a transboundary river basin. The aim of the study is to assess the current state and variability of the river’s water regime and to identify the key natural and anthropogenic factors controlling runoff formation and its temporal dynamics. The research is based on long-term hydrological observations at the Liubkivtsi gauging station covering the period 1985-2020, complemented by modern geospatial and remote sensing approaches. Climatic and hydrological conditions were analyzed using global datasets, including TerraClimate, CHIRPS precipitation data, and GLDAS land surface information, while basin morphometric characteristics were derived from the SRTM digital elevation model using GIS techniques. This combination of ground-based measurements and satellite-derived data enabled a comprehensive assessment of hydroclimatic variability within the catchment. The results indicate that the hydrological regime of the Chorniava River is shaped by the combined influence of climatic variability, geomorphological structure, and human activities within the basin. A statistically significant increase in air temperature has been observed over the study period, accompanied by pronounced variability in precipitation patterns and soil moisture conditions. These changes directly affect runoff generation processes and contribute to increased hydrological instability. The long-term average discharge of the river is estimated at 1.59 m³/s, with substantial interannual and seasonal fluctuations. A noticeable transformation of the seasonal runoff structure has been identified, characterized by a decreasing contribution of spring snowmelt floods and an increasing frequency and intensity of rainfall-driven flood events. This shift reflects ongoing climate change impacts and altered watershed response mechanisms. The findings highlight the necessity of improving hydrological monitoring systems and implementing adaptive water management strategies aimed at enhancing the natural water retention capacity of the landscape. Strengthening ecosystem-based approaches and integrated management practices is essential for mitigating flood risks and ensuring the sustainable use of water resources in the Prut transboundary basin.