The dynamics of climate elements and land drainage impact on hydrologic conditions in a lakeland blind drainage area
The assessment of climate dynamics and the impact of land drainage systems on lakeland blind drainage area was the problem studied in the paper. The research area was located based on relative stability of non-climatic physiographic characteristics and water management practices over a longer time-scale. Thus, the influence of non-climatic factors on water storage could be omitted. The study site was situated in Warmia region in the Dopływ spod Nowej Wsi catchment (27.53 km2). One of local seepage ponds called Bagna Ramuckie within the aforementioned catchment was investigated. The study covered the time period since the first half of the 19th century to the year 2005.
The decisive factors affecting processes of increase and decrease of pond water surface area in considered spatial units were the trends of air temperature over the long time scale. It was indicated that natural enlargement of water surface area in the pond occurred after 40-years long period of air temperature decrease and the decline followed 20-year-long period of air temperature rise. Precipitation did not show any trends for long periods but typical cyclic changes of precipitation over a short time-scale. These pluvial cycles stimulated or destimulated processes of water surface changes additionally over short periods. The first episode of water surface decrease in the seepage pond occurred when air temperature rise trend coincided with intensive land drainage and changes in some land management patterns (the 2nd half of the 19th century). Nevertheless, during the 20th century water management practices were rather stable and did not have any impact on rise or decline of seepage pond water surface area.