Long-term NDVI dynamics in the basin of Lake Baikal

International Conference and Early Career Scientists School on Environmental Observations, Modeling and Information Systems: ENVIROMIS-2018

生态环境科学;计算机科学

Ayurzhanaev, A.A.^1 ; Sodnomov, B.V.^1 ; Garmaev, E Zh^1 ; Tsydypov, B.Z.^1 ; Andreev, S.G.^1 ; Alymbaeva, Zh B^1 ; Tulokhonov, A.K.^1

Baikal Institute of Nature Management SB RAS, Ulan-Ude

670047, Russia^1

关键词: Forest restoration;    Highly-correlated;    Precipitation trends;    Seasonal dynamics;    Spectro-radiometers;    Statistical significance;    Surface air temperatures;    Temperature trends;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/211/1/012041/pdf
DOI  :  10.1088/1755-1315/211/1/012041

来源: IOP

【 摘 要 】

This paper presents an analysis of NDVI distributions and linear trends in the basin of Lake Baikal. Data of a thematic product MOD13Q1 of a MODIS spectroradiometer from 2000 to 2017 are used. Regression analysis is applied for more than 10 million time series. The slope coefficients and their statistical significance are calculated. Trends in surface air temperature and precipitation over the same period are also examined. It is revealed that the histogram of the number of pixels according to NDVI has a two-modal form, the maxima of which correspond to steppe and forest vegetation. 75.18% of the basin area has positive NDVI trends and 24.82%, negative ones. The negative NDVI trends are observed for steppe ecosystems of the Russian part of the basin, and for the steppes of Mongolia and forest ecosystems the trends are positive. For forest vegetation, the greatest and smallest values of trends are observed as a result of deforestation and forest restoration. The precipitation trends are positive in Mongolia and negative in Russia, which is consistent with the NDVI trends for steppes. Non-significant positive temperature trends are observed in the entire territory of the Lake Baikal basin. The seasonal dynamics of NDVI is highly correlated with air temperature and less correlated with precipitation. Preliminary data on the relationship between the width of tree rings and the forest NDVI have been obtained.