Changes of forest land areas in diferent Lithuanian counties: with large and small forested territories

Abstract

The most noticeable changes of the forest land areas were found in Alytus County and Vilnius County which are characterized by larger forested areas in Lithuania. The forest land area has increased by 13.5 % in Alytus County and by 11.4 % in Vilnius County within the period of 1950-2015. In comparison, the increase of forest land areas in Lithuanian regions where agricultural traditions are more common, was much smaller. Forest land area in Marijampolė County has increased only by 4.1 %. However, the increase of forest land area in Klaipėda County was higher – 7.5 %. According to Land Assessment, forest land area occupied 2178.9 thous. ha (33.5 %) of Lithuania’s territory in 2017, as reported by official statistics of Lithuania [3]. Two centuries ago the forest cover proportion in Lithuania was about 40 %. According to Markovienė forest land area decreased, and it was only 20 % in 1914, while in 1939 – only 17 % [1]. In 1950, forests covered 19.7 % of Lithuania territory, as stated by official statistics. This statement was denied by the study in 2012 where historical aerophotos and innovative GIS methods were employed. The study ascertained that forest land area in 1950 was 26.5 %, i. e. notably differing from the official statistics [2]. The aim of this study was as follows: first, to calculate forest land areas in Alytus, Vilnius, Marijampolė and Klaipėda Counties in 1950 and 2015, second, to compare the changes of forest land areas in Alytus and Vilnius Counties that are the most forested regions in Lithuania, with the changes of forest land areas in Marijampolė and Klaipėda Counties, where forests occupy minor territories. In order to calculate the forest land area in a particular territory, forest geodatabase in 1950 and geodatabase of the Lithuanian forest cadastre (2015) were used. Geodata as well as data on forest land area in a particular county was obtained using ArcGIS software, where ArcGIS Clip tool and statistics for table were employed. The results of the study revealed that the forest land area changes in different Lithuanian counties differed within the period of 1950-2015. However, forest land areas in all the investigated counties have increased (Table 1).