Background/Question/Methods
The Carpathian Mountains are Europe’s largest temperate forest ecosystem, a biodiversity hotspot, and provide habitat to large populations of top herbivores and carnivores that have been lost elsewhere in Europe. Yet, changing politics and socio-economic changes after the fall of the Iron Curtain in 1991 are affecting the Carpathian forest ecosystem. Forest statistics indicate decreasing human pressure and an increase in forest land, but fail to capture reforestation on abandoned farmland and illegal logging. The latter is of particular concern in the Ukrainian Carpathians, due to the pronounced economic difficulties, weakened institutions, and the lack of control after the system change. Thus the question how forest cover changed in the Ukrainian Carpathians since 1991 remains unanswered. We used Landsat TM/ETM+ images and a classification approach based on Support Vector Machines (SVM) to classify forest/non-forest maps for four points in time (1990, 1995, 2000, and 2007) for the entire Ukrainian Carpathians. Based on these maps, we derived a change map and calculated logging rates. To assess the role of illegal logging in the region, we compared our results to official forest statistics at the regional and local level.
Results/Conclusions
Our SVM-based classification resulted in reliable forest/non-forest maps (accuracies 95.43-99.40% and kappa 0.90-0.98) and showed widespread forest cover change in the Ukrainian Carpathians during transition. Logging sites were highly clustered and tended to occur inside larger and more remote forests in 2000-2007 compared to 1990-2000, likely due to an increasing scarcity of valuable old stands. In contrast to official forest statistics, forest cover decreased after the system change and logging rates remained at relatively high levels during transition. We suggest illegal logging and the lack of transparency in the Ukrainian forest business likely explain this discrepancy. Our results indicate that illegal logging was most widespread in the early transition years and may have been as extensive as legal logging. Our study provided first evidence about the rates and spatial patterns of post-socialist forest cover change in the Ukrainian Carpathians and showed that these unique forest ecosystems are under much higher pressure than suggested by official forest statistics.