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Выявление и картографирование многолетних трендов NDVI для оценки вклада изменений климата в динамику биологической продуктивности агроэкосистем лесостепной и степной зон Северной Евразии
Northern Eurasian forest-steppe and steppe encompass huge region where observed and projected climate change and in particular change in precipitation regime demonstrate high spatial heterogeneity. In this study,
spatial and temporal variations of croplands and grasslands productivity in the main agricultural regions of
Russia and adjacent countries are indicated by means of sum annual NDVI time series analysis. For the three
decadal periods with different climatic and socio-economic conditions (1980s, 1990s and 2000s) we constructed
time series of NDVI extracted from low-resolution remote sensing data (NOAA AVHRR, Terra MODIS) and
time series of gridded climate data — precipitation and PDSI. Revealed non-parametric significant trends in
sum annual NDVI were analyzed on the concordance of their signs with climate data trends for different for-
est-steppe and steppe ecoregions. Spatial analysis and resulted maps demonstrate the predominance of posi-
tive NDVI trends throughout the region for the 1980s under favorable climatic conditions whereas the 1990s
are characterized with high spatially heterogeneous disagreement between signs of NDVI and climatic trends
with more significant anthropogenic impact on general decline in agro-ecosystems’ productivity. In the 2000s
the presence of extensive belt elongated through dry and deserted steppes from Lower Don basin to the Eastern
Kazakhstan with stable negative NDVI trend under regional aridization verifies results of projected climate
change in this region towards the middle of the 21 century.