How Does the Management Paradigm Contain Wildfire Over Southwest China? Evidence From Remote Sensing Observation.

Severe wildfires have increased and threaten Southwest Sichuan Province China, causing serious death and damage to this region. The local government launched a series of strict policies on wildfire management in 2014, including control of anthropogenic ignition sources and quick response on wildfire suppression when a fire is detected. This study aimed to examine the effectiveness of these policies in containing wildfire in this region based on multiple remotely sensed observation data. We examined the fire event count (FEC) change between 2001 and 2021 based on multiple satellite-based fire products and found the FEC markedly decreased since 2015. Since wildfire occurrence is a non-linear process resulting from interactions between weather, topography, fuel, and anthropogenic factors, to explore which factor led to such FEC decline, we examined three wildfire weather-related variables—the vapor pressure deficit (VPD), Canada forest fire weather index (FWI), synthetical wildfire danger index (WDI), and three fuel load-related variables—foliage fuel load (FFL), aboveground biomass (AGB), and solar-induced chlorophyll fluorescence (SIF). We found no significant ($p>0.05$) increase or decline in wildfire weather trend was observed, whereas a significant fuel load accumulation trend ($p < 0.05$) was identified across this region between 2001 and 2021. As the topography factor is stable, this study, with the lengths of remote sensing observation, demonstrated the effectiveness of the management paradigm containing wildfire over Southwest China. [ABSTRACT FROM AUTHOR]