CHANGES IN THE MOISTURE CONTENT OF THE MIDDLE FEN SOILS IN THE ODRA RIVER VALLEY IN THE REGION OF BRZEG DOLNY IN THE VEGETATION PERIODS 2004–2009

摘要

In soils, where the water table is deeply located and has a minor impact on the moisturecontent of the surface layer, we are dealing with the precipitation-and-water typeof water management. If underground water level is close to the surface, the top stratumof the soil, apart from precipitation, is additionally fed by water absorption fromunderground waters. Then we are dealing with ground-and-water type of management.We consider such types of water management of soil in the area of the left-bankvalley of the Odra river, above and below the dam in Brzeg Dolny. The dominantsoil types here are middle fen soils, based on middle clay and heavy clay as well asloam, which, in conditions of either excess or deficiency of moisture, are difficult tocultivate. The work compares water management of two soil profiles in vegetationperiods between 2004 and 2009. The formation of underground waters, meteorologicalconditions and the course of the water reserves in the strata 0–50 cm and 0–100 cm were estimated with various supplying conditions of the active stratum of the soil.The volume of the supply with percolated water from underground water of the layer50–100 cm on approximately 75–90 mm was also estimated. This value was mainlydependent on the depth of the retention of the water table of the soil profile above thelevel in Brzeg Dolny