Zmiany zapasów wody w latach o różnych sumach opadów, w śródleśnych oczkach wodnych, na przykładzie Leśnictw Wielisławice i Laski

The paper presents the results of researches carried in 2002/2003, 2003/2004 and 2009/2010 hydrological year in catchments pond No 1 and 6 located in Wielsiławice and Laski Forestry at Siemianice Experimental Forest Farm of Poznań University of Life Sciences located about 15 km south-east from Kępno. Analysed areas there are situated is a part of Niesób and Pomianka catchments – left-side tributary of Prosna River. The catchment area of pond No 1 is 7.6 ha, and there is forestation 100%. Whereas the catchment area of pond No 6 is about 37 ha, there is forestation 40% and the rest 60% area investigated catchment is arable lands. Predominance forest habitat in catchments analysis ponds is fresh mixed broadleaved forest, about area 95%, where predominant species of tree stand is 100 years old pine. Analysis pond No 1 and 6, of mild scarps, are natural pond melting out. Area of pond No 1 is 0.13 ha, whereas pond No 6 is 0.35 ha, and averages depths are properly 1.0 m and 1.4 m. Hydrological year 2002/2003, in which the rainfall total was 68 mm lower than average multiannual rainfall, was a dry year. In average hydrological year 2003/2004 rainfall total was 47 lower than multiannual rainfall. Whereas hydrological year 2009/2010, in which the rainfall total was 281 mm higher than average multiannual rainfall, was a wet year. The researches confirmed, that water storages in pond No 1 and 6 renovation in year cycle was depend of meteorological conditions. Water level changes and related water storage changes were especially connected to precipitation sums in individual half-year analysis year. The researches show to, that in all analyzed hydrological years higher water storage changes about -100 mm to 480 mm, in pond No 1, were has about 0.22 ha lower area than pond No 6. Whereas changes water storage in pond No 6 reached, in analyzed years, value about -25 mm to 340 mm.