摘要:The development of continental-scale fire mapping using AVHRR since the early 1990s and, more recently, MODIS imagery, is transforming our understanding of Australian fire regimes—particularly the national significance of savanna burning. The savannas of northern Australia are the most fire-prone part of a fire-prone continent. The savanna region comprises 1,898,562 km 2 (24.7% of the Australian landmass), of which 21% has been burnt on average each year, over the period 1997–2005. Savanna fires currently contribute about 68% of national fire extent annually—the remainder comprising mostly fire in central Australia (associated in recent years with decadally high rainfall, hence high fuel loads), with just 2% in relatively densely populated southern Australia. At finer scales of resolution employing LANDSAT imagery, northern Australian studies since the early 1980s are providing novel landscape-scale assessments including monitoring of fire regime heterogeneity and biomass burning emissions. While seasonality has been shown in a number of studies to be correlated with fire intensity, remote sensing studies of fire severity are just commencing. The paper particularly addresses recent north Australian studies that explore the importance of spatial and temporal patchiness in fire extent and severity.
关键词:fire frequency ; fire history ; fire regime heterogeneity ; greenhouse gas emissions ; obligate seeder ; satellite imagery