Land Drainage Development Process and Runoff Changes in Lithuanian Rivers

Abstract

There is water surplus in soils in more than half of the Lithuanian territory. As a matter of fact, to have favourable conditions for farming, too wet areas are drained by drainage (about 77% of the area to be drained has already been drained). The paper discusses the existing status of the drainage systems and analyses the effect of the drainage on river runoff. However, to calculate the effect is rather complicated, because changes in the runoff are affected by a number of factors such as physical-geographical as well as climate conditions, economy activities within the river basin, etc. As a result, only tendencies of the changes in the river runoff during different year seasons have been followed and analysed.