Dynamics of annual radial increment of Scots pine (Pinus sylvestris L.) growing in forest ecosystems on the shores of lakes

The dendrochronological research of Scots pine (Pinus sylvestris L.) growing in the vicinity to kettle lakes Kreivasis (closed lake) and Duobulis (flowing lake) was carried out in 2000-2002. The study is aimed to estimate the influence of water level fluctuations to the formation of radial increment of trees and to create series of radial increment of Pinus sylvestris L. trees growing on the shorelines and in control stands. It was estimated that annual radial increment of pines growing on the shorelines of lake Kreivasis slightly negatively correlates (r = -0.21; P= 0.95) with the increase in water level. During the humid period, when water level remains high for quite a long time, many pine trees growing in the lakeshore zone die. The increase of radial increment of pines on the shorelines of Kreivasis is typical during the periods with small amount of precipitation (in 1932, 1937-1939, 1964-1977, 1997-2002). The annual radial increment of the control stand of lake Kreivasis, the stand on the shorelines of lake Duobulis and its control stand have decreased in the periods with small amount of precipitation as well. There are plenty of nutrient substances (various sediments came into it together with the water and most of them settle down in the lake from higher waters) on the shores of the open lake Duobulis. Meanwhile on the shores of the flowing water lake Kreivasis only the remains of water plants are accumulated.