摘要:In Huascarán National Park (HNP), Peru, grazing and anthropogenic burning have been interacting for decades with natural ignitions and climate variability to reconfigure the fire regimes of the vegetative communities. However, over the last few decades, human alterations to the region’s fire regime were perceived by resource managers to have led to an overall increase in fire occurrence and fire extent. Resource managers are now very concerned about the impacts of increasing anthropogenic fires in the National Park because these fires seem to disrupt ecological processes and tourism. To test these beliefs and examine the fire activity from 2002 to 2014, we used a time series of several different data products including the MODIS Terra and Aqua platforms (Active Fire and Burned Area) as well as local air temperature and precipitation data. The intra-annual distribution of fires in the HNP and its buffer zone (BZ) showed a consistent increase in the number of active fires and burned areas during the dry season (Peruvian winter). The active fire anomalies showed higher fire activity in the HNP over the period 2002 to 2014. However, burned area anomalies showed consistently higher fire activity in the BZ during the high fire years in 2003, 2005, 2010, and 2014. The spatial distribution of areas burned in the HNP and the BZ from 2002 to 2014 showed that most recurrent burning was inside the BZ, which is in compliance with the HNP’s policy but in contradiction with local resource managers’ perceptions. Although human activity may influence local fire dynamics, fire responses seemed to be mainly influenced by local climate oscillations. Our results suggest a clear fire response to local climate and, in particular, to precipitation variability. However, it appears that there was a low fire return interval for any given location and that the total area burned for a given year is relatively small. Therefore, small-scale fires created an appearance of larger fire impacts than actually occur within the HNP and its BZ. In this instance, fire perception and fire reality are not aligning and the new challenge for resource managers is how best to reconcile these two factors to more effectively manage the parklands.
关键词:Andes ; climate variability ; fire extent ; fire occurrence ; MODIS ; Peru ; satellite imagery