Hidrologija

Hidrologija is the science concerned with the distribution, movement, and properties of Earth's water. It studies how water enters, moves through, and leaves the atmosphere, surface, and subsurface environments, and how it stores and is transformed within rivers, lakes, soils, glaciers, and groundwater. The field examines the hydrological cycle and the interactions between water, landforms, climate, ecosystems, and human activities. The term derives from Greek hydor (water) and logos (study).

It encompasses several subfields, including surface hydrology, which deals with streams, lakes, and runoff; hydrogeology, which focuses on groundwater; hydrometeorology, which links weather and climate to hydrological processes; and related areas such as ecohydrology and hydroinformatics. Researchers collect data, develop conceptual and mathematical models, and use simulations to estimate flows, storage, and water quality.

Methods include field monitoring (rain gauges, stream gauges, groundwater wells), surveys of soil moisture, remote sensing, and geographic information systems. Models range from simple rainfall-runoff models to physically based distributed models and data-driven approaches. Forecasting and flood and drought risk assessment are key applications, alongside water resources planning, design of hydraulic structures, and environmental management.

Hidrologija plays a central role in sustainable development by informing water allocation, ecosystem protection, and climate adaptation. It integrates natural science with engineering, policy, and community needs to manage water resources under variability and change.