Comparison of vegetation regeneration after wildfire between Mediterranean and tundra ecosystems by using Landsat images

Figures & data

Figure 1. Landsat 5 image on 17 January 2008 shows the burn scar of Witch Creek Fire (33°9ʹN 116°49ʹW). Band combination – 3:2:1 – red:green:blue. Red line indicates the study area.

Figure 2. Landsat 5 image on 14 June 2008 shows the burn scar of Anaktuvuk River Fire (69°21ʹN 150°50ʹW). Band combination – 3:2:1 – red:green:blue. Red line indicates the study area.

Table 1. Satellite images used for the WCF.

Sensor	Date of image acquisition	Status	WRS2
	7 August 2006^b
	14 January 2007^a
	10 August 2007^b
	17 January 2008^a
	27 July 2008^b
	15 August 2009^b
	17 July 2010^b
	5 August 2011^b
	10 August 2013^b
	13 August 2014^b
	15 July 2015^b

WRS2: Worldwide Reference System-2.

^aDenotes the images that are used for calculating the NBR; ^bdenotes the images that are used for the NDVI.

Table 2. Satellite images used for the ARF.

Sensor	Date of image acquisition	Status	WRS2
	15 June 2005^a		74/11
	28 August 2006^b		75/11
	14 June 2008^a		75/11
	23 June 2008^b		74/11
	19 July 2009^b		75/11
	25 August 2010^b		73/11
	14 July 2013^b		75/11
	10 July 2014^b		74/11
	22 July 2015^b		73/11

WRS2: Worldwide Reference System-2.

^aDenotes the images that are used for calculating the NBR; ^bdenotes the images that are used for the NDVI.

Table 3. Thresholds of burn severity levels as proposed by Key and Benson (2006).

dNBR ranges	Burn severity level
−0.1–0.099	Unburned
0.1–0.269	Low severity
0.27–0.439	Moderate–low severity
0.44–0.659	Moderate–high severity
0.66–1.3	High severity

dNBR: differenced normalized burn ratio. Low severity refers to vegetation partly consumed by fire while high severity refers to complete consumption of aboveground vegetation after fire.

Figure 3. Trends of vegetation regeneration in the cases of WCF and ARF.

Figure 4. Burn severity classification of WCF.

Figure 5. Burn severity classification of ARF. Black colour indicates the wildfire area which was beyond the scope of our study.

Figure 6. Land cover retrieved from NLCD.

Figure 7. Time series of NDVI of WCF from Landsat images through 2006–2015.

Figure 8. Time series of NDVI of ARF from Landsat images through 2006–2015. Legends refer to Figure 7.

Table 4. Land-cover information extracted from NLCD 2006 for WCF and NLCD 2001 for ARF.

WCF	Occupied percentage	ARF	Occupied percentage
Emergent herbaceous wetlands	<1	Barren land	<1
Evergreen forest	5	Dwarf scrub	62
Grassland/Herbaceous	2	Emergent herbaceous wetlands	1
Mixed forest	9	Sedge/herbaceous	32
Shrub/Scrub	84	Shrub/scrub	4
Woody wetlands	<1	–	–
Total	100	Total	100

Figure 9. Changes in number of patches after wildfires.

Figure 10. Regeneration index of vegetation under different burn severities in WCF. Note that there is a lack of data in 2012.

Figure 11. Regeneration index of vegetation under different burn severities in ARF. Note that there is a lack of data in 2011 and 2012.

Key, C. H., and N. C. Benson. 2006. “Landscape Assessment (LA): Sampling and Analysis Methods. USDA Forest Service Gen. Tech. Rep. RMRS-GTR-164-CD.” Accessed 10 August 2017. https://www.frames.gov/rcs/0/598.html.

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