geohydrologi

Geohydrology, or geohydrologi in some languages, is the science that studies groundwater—its distribution, occurrence, and movement within the soils and rocks of the Earth's crust. It focuses on understanding where groundwater is found, how it flows, how much can be sustainably taken, and how it interacts with surface water bodies such as rivers, lakes, and wetlands. Geohydrology is closely related to hydrogeology, with some contexts treating geohydrology as a regional or geological emphasis within hydrogeology.

Key concepts in geohydrology include aquifers (water-bearing formations) and aquitards (low-permeability layers), porosity, permeability, and hydraulic conductivity, which describe how much water a rock can hold and how easily it can move. Variables such as recharge (water entering the groundwater system), discharge (water leaving), storativity, and transmissivity characterize groundwater storage and flow. Groundwater movement is commonly described by Darcy’s law, and systems are categorized as confined, unconfined, or perched aquifers. Geohydrology also studies interactions between groundwater and surface water, as well as issues like saline intrusion, contamination transport, and groundwater-surface water coupling.

Methods used to investigate geohydrology include field drilling, borehole logging, aquifer pumping tests, tracer tests, and geophysical surveys. Hydrochemical analyses, water quality monitoring, and groundwater modeling (conceptual and numerical models such as MODFLOW) are used to quantify resources, predict responses to pumping or climate change, and guide management decisions.

Applications of geohydrology encompass water supply planning for communities and agriculture, environmental protection and remediation, mining and construction projects, and risk assessment for subsidence, flooding, and contamination.