Impact of small mid-forest water reservoirs on trees radial increment

The aim of the study was to determine the effect of small forest water reservoirs on the radial increment of Scots pine and Norway spruce. We selected four small water reservoirs that were reconstructed in autumn 2006 in the Maskulińskie Forest District (northern Poland). Around each reservoir we placed transects according to the cardinal directions. At those transects we set up 10×10 m sample plots at different distances from the edge of the water reservoirs. On the each sample plot we made simplified phytosociological releve and set the type, subtype, and variety of soil. The impact of the water reservoirs on the radial increment was determined for Scots pine and Norway spruce growing on transects. Conducted research showed that the examined species stronger reacted to the water stored in the reservoirs by diameter increase in the initial two or three years after the reservoir reconstruction. The increment of Scots pine growing near to edge of the water reservoirs (up to 20 m) was reduced. In contrast, there was no significant impact of environmental features or weather conditions on radial increment of the analysed species