Papers / Études et communications Rev. Roum. Géogr./Rom. Journ. Geogr., 59, (2), p. 91–100, 2015, Bucureşti. OBSERVED AND PROJECTED CLIMATE CHANGE AND ITS IMPACT ON ECOSYSTEMS’ PRODUCTIVITY IN FOREST-STEPPE AND STEPPE ZONES OF RUSSIA AND NEIGHBORING (FSU) COUNTRIES NICOLAY DRONIN ∗ , NATALIA TELNOVA ∗∗ , ANDREY KIRILENKO ∗∗∗ , ELENA MILANOVA ∗∗∗∗ , NATALIA KALUTSKOVA ∗∗∗∗∗∗ Key-words: FSU region, current and future climate, impacts of climate change on agriculture, biological productivity, NDVI. Abstract. The paper compares model projections of climate change in the main grain-producing region of Eastern Europe with currently observed climate change and its impact on biological productivity of ecosystems. Spatial pattern comparable analysis of some climate variables and NDVI time series proves projections of aridization of the forests-steppe and steppe zones for the whole region with some exclusion for the territories experienced local increase of precipitation or better land management. The study confirms continuing aridization of the forest-steppe and steppe zone of the FSU region during the 2000s. 1. INTRODUCTION Although economic and institutional changes have been probably the dominant factor influencing the agricultural sector in post-Soviet transitional economies, agricultural production is also highly sensitive to inter-annual climate variability and in general to climate change. Generally, the geography of agriculture of the Former Soviet Union (FSU) follows two climatic factors: temperature and summer precipitation. According to the majority of GCM projections, these factors will be significantly modified in the future (Table 1). Compared with the historical climate, the temperature in the FSU region in the 2020s, averaged over the GCM projections, will increase by 1.5°C on average, with higher increase in the South Siberian region. Precipitation demonstrates high variability, with a greater increase in Siberia and the North-West regions, lower increase in the South European region, and a decrease in the Transcaucasia region. In the 2050s, the temperature change in the regions continues to follow this pattern. Annual precipitation will increase by 41–51 mm in the North-West and South Siberian regions, 11–28 mm in the South European regions, and decrease by 22–55 mm in Transcaucasia. Finally, in the 2080s the temperature will increase by 4.5°C on average, following the west-east gradient, with large differences between the regions (Kirilenko, Dronin, 2011). In the North- West region, but not in the South European and South Siberian regions, increasing precipitation will compensate additional evapotranspiration due to higher temperatures. This will lead to aridization of forest-steppe and steppe zones of the FSU countries. As projected indexes of aridity show, Transcaucasia is expected to be the most arid region (Table 1). ∗ Professor, Head of laboratory, Faculty of Geography, Moscow State University, 119991, Russian Federation, Moscow, GSP-1, Leninskie gory, ndronin@gmail.com. ∗∗ Senior Researcher, Faculty of Geography, Moscow State University, 119991, Russian Federation, Moscow, GSP-1, Leninskie gory, natalia.telnova@gmail.com. ∗∗∗ Associate Professor, Department of Earth System Science and Policy, University of North Dakota, USA, Grand Forks, ND 58202-9011, akirilen@aero.und.edu. ∗∗∗∗ Associate Professor, Faculty of Geography, Moscow State University, 119991, Russian Federation, Moscow, GSP-1, Leninskie gory, elena.v.milanova@gmail.com. ∗∗∗∗∗ Associate Professor, Faculty of Geography, Moscow State University, 119991, Russian Federation, Moscow, GSP-1, Leninskie gory, nat_nnk@mail.ru.