Land cover change on the Isthmus of Karelia 1939–2005: Agricultural abandonment and natural succession

Abstract

The Isthmus of Karelia is located in North-West Russia, between Lake Ladoga and the Baltic Sea. At the end of World War II (WWII), Finland ceded the western part of the Isthmus to the Soviet Union. In 1991 the Soviet Union ceased to exist. The Isthmus became a part of the Russian Federation. Using land cover data from the years 1939, 1987 and 2005 we document and analyze land use change on the Isthmus during and after the Soviet era. Large-scale agricultural abandonment was observed during the Soviet era. The landscape share of agriculture halved from 18 to 9%, as only a part of the land vacated by Finnish farmers during WWII was incorporated into the Soviet agricultural system. Forest expanded onto farmland and its landscape share increased from 72 to 77%. Another observed trend was the recovery from previous forest degradation. As logging on the Isthmus was banned, the development of the forest mosaic followed patterns of natural succession. Some deciduous forests were transformed into mixed forests and spruce forests. Clear cuts and sapling stands became rare. After the collapse of the Soviet Union, logging in old growth forests was resumed. However, its impacts on the regional forest composition remained modest. The recent forest history of the Isthmus is an extreme example of recovery from earlier forest degradation in boreal conditions. To illustrate the magnitude of the changes, we contrast our findings with the contemporary development in Southern Finland, where land use remained stable and forests were intensively utilized for timber production.