Conference Paper

Analyzing a North American prairie wildfire using remote sensing imagery

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Abstract

Grassland wildfires have profound immediate effects on ecosystems. A wildfire that occurred in Grasslands National Park (GNP) on April 27th2013 has severely disturbed the local ecosystem. This study was thus conducted to evaluate impacts of the fire on this semi-arid grassland. Spectral indices including Normalized Burn Ratio (NBR), Mid-Infrared Burn Index (MIRBI), and Normalized Difference Vegetation Index (NDVI), derived from Landsat images were explored to evaluate the burn severity, to assess the relationship between pre-fire vegetation parameters and burn severity, and to analyze the vegetation recovery progress. Results indicated that while the selected spectral indices were all able to detect burn severity, the MIRBI showed the best performance. Severely burned areas were distributed along a river where a large amount of pre-fire dead biomass had accumulated. Overall the grassland ecosystem showed a strong resilience by recovering quickly after the fire.

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... The relatively short burned area persistence time for temperate grassland was also observed in Canadian grassland fires. In these grasslands, Lu and He [138] estimated the post-fire vegetation recovery using multi-temporal Landsat imagery (one, two and three months after the fire) and concluded that grassland has a strong post-fire recovery capacity, especially if there is an adequate water availability. Prescribed fires are commonly used in tallgrass prairie ecosystems and are characterized by a relatively small-sized high degree of combustion heterogeneity, for this reason, MODIS' coarse resolution could be insufficient for an adequate mapping of this type of fire [139]. ...
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M. Findlay, "Hinterland Who's Who,"
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Parks Canada, "Grasslands National Park Introduction," http://www.pc.gc.ca/pn-np/sk/grasslands/natcul/natcul1.aspx, available at March 3rd, 2014.
USGS Archive and Available Scenes
  • U S Survey