Garmaev E.Zh.,  Ayurzhanaev A.A.,  Tsydypov B.Z.,  Alymbaeva Zh.B.,  Sodnomov B.V., Andreev S.G.,  Zharnikova M.A.,  Batomunkuev V.S.,  Mandakh N., Salikhov T.K.,  Tulohonov А.К.  ASSESSMENT  OF  SPATIAL – TEMPORAL VARIABILITY OF ARID ECOSYSTEMS IN THE REPUBLIC OF BURYATIA // Arid ecosystems. 2020. V. 26. № 2 (83). P. 34-42. | PDF

Climate change and human activity on the territory of the Republic of Buryatia intensify the processes of desertification and land degradation. Zoning of the territory of Buryatia was carried out according to the aridity index using ENVIREM high spatial resolution climatic data. Based on the correlation analysis of the time series of the NDVI AVHRR vegetation index, meteorological series of the NCEP / NCAR reanalysis and field studies, a quantitative assessment of the long-term changes in vegetation cover in arid and humid zones was carried out. Maps of the spatial distribution of linear trends of NDVI and precipitation for 1982-2015 with the separation of wet (1982-1999) and dry periods (2000-2015) were obtained. During the wet period, positive NDVI trends are observed for almost the entire territory of the Republic, while the dry period is characterized by a significant increase in the negative trends of the vegetation index. The positive correlation between the Selyaninov hydrothermal coefficient and NDVI is observed for intermountain steppificated hollows, negative for forest landscapes. The dynamics of NDVI of steppe vegetation largely depends on precipitation, the dynamics of NDVI of forests — on temperature. Reforestation, post-pyrogenic succession, shrubbing of abandoned fields, etc., cause the increase of NDVI. Negative NDVI trends are typical for steppe ecosystems under conditions of decreasing precipitation, and for forest vegetation prone to cuttings and fires.

Keywords: Buryatia, arid zones, vegetation, NDVI, Selyaninov hydrothermal coefficient, precipitation, trend, reanalysis, dendrochronology.

DOI: 10.24411/1993-3916-2020-10093