Fire and vegetation dynamics in northwest Siberia during the last 60 years based on high-resolution remote sensing

Biogeosciences

article

Sizov, Oleg¹  Köster, Kajar²  Ezhova, Ekaterina³  Tsymbarovich, Petr⁴  Soromotin, Andrey⁵  Prihod'ko, Nikolay⁵  Petäjä, Tuukka³  Zilitinkevich, Sergej³  Kulmala, Markku³  Bäck, Jaana² 

[1] Institute of Oil and Gas Problems, Russian Academy of Sciences;Institute for Atmospheric and Earth System Research (INAR)/Forest Sciences, University of Helsinki;Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki;Department of Physical Geography and Environmental Management Problems, Institute of Geography, Russian Academy of Sciences;Research Institute of Ecology and Natural Resource Management, Tyumen State University;Finnish Meteorological Institute

DOI  :  10.5194/bg-18-207-2021

学科分类：大气科学

来源: Copernicus Publications

【 摘 要 】

The rapidly warming Arctic undergoes transitions that can influence global carbon balance. One of the key processes is the shift towards vegetation types with higher biomass underlining a stronger carbon sink. The shift is predicted by bioclimatic models based on abiotic climatic factors, but it is not always confirmed with observations. Recent studies highlight the role of disturbances in the shift. Here we use high-resolution remote sensing to study the process of transition from tundra to forest and its connection to wildfires in the 20 000  km 2 area in northwest Siberia. Overall, 40  % of the study area was burned during a 60-year period. Three-quarters of the burned areas were dry tundra. About 10  % of the study area experienced two–three fires with an interval of 15–60 years suggesting a shorter fire return interval than that reported earlier for the northern areas of central Siberia (130–350 years). Based on our results, the shift in vegetation (within the 60-year period) occurred in 40 %–85 % of the burned territories. All fire-affected territories were flat; therefore no effect of topography was detected. Oppositely, in the undisturbed areas, a transition of vegetation was observed only in 6 %–15 % of the territories, characterized by steeper topographic slopes. Our results suggest a strong role of disturbances in the tree advance in northwest Siberia.

【 授权许可】

CC BY