Classification of Fire Damage to Boreal Forests of Siberia in 2021 Based on the dNBR Index

Abstract

Wildfire in Siberia is extensive, affecting up to 15 Mha annually. The proportion of the vegetation affected by severe fires is yet unknown, and it is a problem that requires a solution because post-fire mortality of tree stands in Siberian taiga has a strong effect on the global budget of carbon. The impact of fire in our area of interest in eastern Siberia was analyzed using the normalized burn ratio (NBR) and its pre- versus post-fire difference (dNBR) applied to Landsat-8 (OLI) collected in 2020–2021. In this paper, we present the classification of fire impact in relation to dominant tree stands and vegetation types in boreal forests of eastern Siberia. The dNBR of post-fire plots ranged widely (0.30–0.60) in homogeneous larch (Larix sibirica, L. gmelinii) forests, pine (Pinus sylvestris) forests, dark coniferous stands (Pinus sibirica, Abies sibirica, Picea obovata), sparse larch stands, and Siberian dwarf pine (Pinus pumila) stands. We quantified the proportions of low, moderate, and high fire severity (37%, 39%, and 24% of the total area burned, respectively) in dense tree stands, which were varied to 30%, 57%, and 13%, respectively, for sparse stands and tundra vegetation dominated in the north of eastern Siberia. The proportion of severe fires varied according to the transition from dominant larch stands (33.2% of the area burned) to pine (12.6%) and dark coniferous (up to 26.4%). The current proportion of stand-replacement fires in eastern Siberia is 12–33%, depending on vegetation type and tree density, which is about 2500 thousand hectares in 2021 in the region. According to our findings, the “healthy/unburned vegetation” class was quantified as well at least 700 thousand hectares in 2021.

Geospatial assessment of vegetation condition pre-wildfire and post-wildfire on Luštica (Montenegro) using differenced Normalized Burn Ratio (dNBR) index

“…This kind of geospatial assessment using the dNBR index has been validated many times in different geographical conditions, and its high efficiency has been widely discussed in previous studies (Jovanović & Ţupan 2017;Potić et al, 2017;Llorens et al, 2021;Alcaras et al, 2022;Ponomarev et al, 2022). This study shows the possibility of assessing vegetation's condition pre-wildfire and post-wildfire based on Sentinel-2a satellite images in a QGIS environment using the dNBR index.…”

“…The application of Normalized Burn Ratio (NBR) and differenced Normalized Burn Ratio (dNBR) indices using satellite images has been the subject of many studies in various wildfire-affected landscape areas and is considered to be effective for identifying damage to burned areas (Roy et al, 2006;Miller & Thode, 2007;Keeley, 2009;Veraverbeke et al, 2010;Parker et al, 2015;Potić et al, 2016Potić et al, , 2017Potić et al, , 2019Jovanović & Ţupan 2017;Santos et al, 2020;Alcaras et al, 2022;Ponomarev et al, 2022).…”

Forest structure and individual tree inventories of north-eastern Siberia along climatic gradients

“…While the analysis of the forest loss dataset led to the expected result that the sites with recent forest loss tend to have lower fractions of living basal area, it is still surprising that we saw some plots that were supposedly affected by forest loss, and thus by fire, with a large part of the stand alive, both in absolute and relative terms. This may be because many forest fires in Siberia are low-intensity fires (Ponomarev et al 2022), which are detected as burned forest in one year, even though a large part of the trees recovers by the following year. Revisiting some of our survey sites in the future may help to improve the understanding of this topic.…”

Temporal and Spatial Analyses of Forest Burnt Area in the Middle Volga Region Based on Satellite Imagery and Climatic Factors

“…On the other hand, large-scale wildfires pose a serious threat, destroying the ecological balance of terrestrial ecosystems [26,27], leading to the loss of bioresources [28][29][30], and causing extensive damage to both human lives and property [31,32]. These fires have a detrimental impact on the resilience of ecosystems to climate change, resulting in a loss of habitats and biodiversity, and a reduction in forest value and productivity, thereby endangering human life [33].…”