improved mapping of vegetation and fuel type using …...trimble rtk gps was used to get the...

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. Motivation: In Alaska increasing frequency, area burned, and intensity of boreal wildfires are driving major ecological changes and increasing community vulnerability. Fire managers use vegetation and fuel types map products generated from satellite imagery to assess fire risk, predict fire behavior, and mitigate fire risk. In Alaska, the best fuel type map available to fire managers are the LANDFIRE program’s Existing Vegetation (EVT) and Fuel map derived from Landsat 30m images. These products not only lack the granularity necessary to effectively evaluate local fire risk, but also have lower accuracy i.e. many important fuel types are mapped incorrectly. Our goal is to improve the existing boreal vegetation and fuel maps by using higher spatial and spectral resolution hyperspectral imagery at select test sites and scaling up to the entire boreal domain using moderate resolution Landsat imagery. Improved mapping of vegetation and fuel type using NASA AVIRIS-NG hyperspectral data, Bonanza Creek, AK Chris Smith, Santosh Panda, Uma Bhatt, Franz Meyer, and Robert Haan The three study sites used in this project are Bonanza Creek Experimental Forest, University of Alaska Fairbanks Campus and Caribou-Poker Creeks Research Watersheds. Data: AVIRIS-NG Hyperspectral image Plot-scale vegetation survey RTK GPS data Trimble RTK GPS was used to get the coordinates of vegetation plots with less than a 0.5 meter accuracy. Future Directions: Expand class signature database Run Random Tree classification on all bands Repeat classification techniques at two other sites Calculate percentage of spruce and grass in a pixel (spectral unmixing) Map canopy moisture Scale up from AVIRIS-NG to Landsat 10x10 vegetation plots were used to determine vegetation classes and will be used for accuracy assessment. Left: LANDFIRE EVT product created from 30 meter Landsat imagery; Right: Vegetation mapped from 5 meter AVIRIS-NG imagery. LANDFIRE EVT mapped 8 vegetation classes (% cover > 1) in the areas shown above whereas we mapped 20 classes using Random Tree classifier. Accuracy Assessment: Based off ground data the EVT correctly classified 13 of the 41 vegetation plots while AVIRIS-NG Random Tree classifier correctly classified 33 of the 41 at the Viereck level IV, and 37 of 41 at furl type level (Barnes et al. 2018). Acknowledgement: Thanks to the NASA ABoVE for collecting and allowing access to AVIRIS-NG scenes. AVIRIS-NG data collected from the NASA ABoVE project can be found at https://daac.ornl.gov/resources/tutorials/search-above-data/. This material is based upon work supported by the National Science Foundation under award #OIA-1753748 and by the State of Alaska. Accuracy: 90% Accuracy: 32% Closed Black Spruce Forest Closed Paper Birch/Quaking Aspen Forest Post Harvest Bluejoint Grass Wet Sedge Meadow Differences in spectral returns were used to classify vegetation classes More 10x10m vegetation plots will be used to further improve classification of low accuracy classes. Open White Spruce Closed Tall Shrub Birch/Willow Shrub Closed Paper Birch Forest Closed White Spruce Forest Wet Sedge Meadow Closed Tall Alder Random Tree classified image derived from a 5-band principal component analysis of a 304-band AVIRIS-NG image collected July 23, 2018. Conclusions: For Bonanza Creek Experimental Forest (BCEF) site, AVIRIS-NG hyperspectral data can identify and map boreal vegetation at Vireck level IV with an accuracy of 79% and at Barnes et al. (2018) fuel type level with an accuracy of 90%. LANDFIRE program's Existing Vegetation Type map for BCEF site is 32% accurate as per our field surveyed vegetation plots. Hyperspectral remote sensing is highly effective and accurate in mapping vegetation/fuel type and improving the granularity of boreal landcover maps. AVIRIS-NG: Airborne Visible InfraRed Imaging Spectrometer - Next Generation is a hyperspectral sensor devolved by NASA. The sensor measures wavelengths from 380-2550 with a spatial sampling of 5 nm.

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Page 1: Improved mapping of vegetation and fuel type using …...Trimble RTK GPS was used to get the coordinates of vegetation plots with less than a 0.5 meter accuracy. Future Directions:

.

Motivation:• In Alaska increasing frequency, area burned, and intensity of boreal wildfires are

driving major ecological changes and increasing community vulnerability. • Fire managers use vegetation and fuel types map products generated from satellite

imagery to assess fire risk, predict fire behavior, and mitigate fire risk. • In Alaska, the best fuel type map available to fire managers are the LANDFIRE

program’s Existing Vegetation (EVT) and Fuel map derived from Landsat 30m images. These products not only lack the granularity necessary to effectively evaluate local fire risk, but also have lower accuracy i.e. many important fuel types are mapped incorrectly.

• Our goal is to improve the existing boreal vegetation and fuel maps by using higher spatial and spectral resolution hyperspectral imagery at select test sites and scaling up to the entire boreal domain using moderate resolution Landsat imagery.

Improved mapping of vegetation and fuel type using NASA AVIRIS-NG hyperspectral data, Bonanza Creek, AK

Chris Smith, Santosh Panda, Uma Bhatt, Franz Meyer, and Robert Haan

The three study sites used in this project are Bonanza Creek Experimental Forest, University of

Alaska Fairbanks Campus and Caribou-Poker Creeks Research Watersheds.

Data:• AVIRIS-NG Hyperspectral image

Plot-scale vegetation survey• RTK GPS data

Trimble RTK GPS was used to get the coordinates of vegetation plots with less than a

0.5 meter accuracy.

Future Directions:• Expand class signature database• Run Random Tree classification on all bands• Repeat classification techniques at two other sites• Calculate percentage of spruce and grass in a pixel

(spectral unmixing)• Map canopy moisture • Scale up from AVIRIS-NG to Landsat

10x10 vegetation plots were used to determine vegetation classes and will be used for accuracy

assessment.

Left: LANDFIRE EVT product created from 30 meter Landsat imagery; Right: Vegetation mapped from 5 meter AVIRIS-NG imagery. LANDFIRE EVT mapped 8 vegetation classes (% cover > 1) in the areas shown above whereas we mapped 20 classes using Random Tree classifier. Accuracy Assessment: Based off ground data the EVT correctly classified 13 of the 41

vegetation plots while AVIRIS-NG Random Tree classifier correctly classified 33 of the 41 at the Viereck level IV, and 37 of 41 at furl type level (Barnes et al. 2018).

Acknowledgement: Thanks to the NASA ABoVE for collecting and allowing access to AVIRIS-NG scenes. AVIRIS-NG data collected from the NASA ABoVE project can be found at https://daac.ornl.gov/resources/tutorials/search-above-data/. This material is

based upon work supported by the National Science Foundation under award #OIA-1753748 and by the State of Alaska.

Accuracy: 90%Accuracy: 32%Closed Black Spruce Forest Closed Paper Birch/Quaking Aspen Forest

Post Harvest Bluejoint Grass Wet Sedge Meadow

Differences in spectral returns were used to classify vegetation classes

More 10x10m vegetation plots will be used to further improve classification of

low accuracy classes.

Open White Spruce Closed Tall Shrub Birch/Willow ShrubClosed Paper Birch Forest Closed White Spruce Forest Wet Sedge MeadowClosed Tall Alder

Random Tree classified image derived from a 5-band principal component analysis of a 304-band AVIRIS-NG image collected July 23, 2018.

Conclusions:• For Bonanza Creek Experimental Forest (BCEF) site, AVIRIS-NG hyperspectral data

can identify and map boreal vegetation at Vireck level IV with an accuracy of 79% and at Barnes et al. (2018) fuel type level with an accuracy of 90%.

• LANDFIRE program's Existing Vegetation Type map for BCEF site is 32% accurate as per our field surveyed vegetation plots.

• Hyperspectral remote sensing is highly effective and accurate in mapping vegetation/fuel type and improving the granularity of boreal landcover maps.

AVIRIS-NG: Airborne Visible InfraRed Imaging Spectrometer - Next Generation is a hyperspectral sensor devolved by NASA. The sensor measures wavelengths from 380-2550 with a spatial sampling of 5 nm.