Wp?yw zbiornika retencyjnego Je?ewo na po?o?enie zwierciad?a wód gruntowych na terenach przyleg?ych

摘要

The presented paper contains study results referring to the depth of groundwater mirror on the area adjacent to the retention reservoir Je?ewo. Study results include the period from the year 2002 to 2008. A direct influence on the level of groundwater mirror in the particular control wells was exerted by the water level in the reservoir. Analysis of seven years of studies indicated that the mirror of groundwater in the zone of a potential influence of the Je?ewo reservoir showed a differentiated level. In all control wells, the shallow water level was changing in a cyclical way, both before and after the filling of the reservoir with water. The observation of the decreasing groundwater level was connected with the vegetation in which water uptake by plants was significantly increased. This cyclicity was connected mainly with the relation between rainfalls and evapotranspiration in summer period with a shortage of rainfalls, in relation to evapotranspiration, leads to soil drying and to lowering of groundwater mirror. On the other hand, in the autumn-spring period, when rainfalls exceed evapotranspiration, there follows a reconstruction of soil retention and the level of groundwater mirror increases.