Canadian Forest Service Publications
The Multisource Vegetation Inventory (MVI): A satellite-based forest inventory for the Northwest Territories Taiga Plains. 2022. Castilla, G.; Hall, R.J.; Skakun, R.S.; Filiatrault, M.; Beaudoin, A.; Gartrell, M.; Smith, L.; Groenewegen, K.; Hopkinson, C.; Van der Sluijs, J. Remote Sensing 14(5):1108.
Year: 2022
Issued by: Northern Forestry Centre
Catalog ID: 40745
Language: English
Availability: PDF (download)
Available from the Journal's Web site. †
DOI: 10.3390/rs14051108
† This site may require a fee
Abstract
Sustainable forest management requires information on the spatial distribution, composition, and structure of forests. However, jurisdictions with large tracts of noncommercial forest, such as the Northwest Territories (NWT) of Canada, often lack detailed forest information across their land base. The goal of the Multisource Vegetation Inventory (MVI) project was to create a large area forest inventory (FI) map that could support strategic forest management in the NWT using optical, radar, and light detection and ranging (LiDAR) satellite remote sensing anchored on limited field plots and airborne LiDAR data. A new landcover map based on Landsat imagery was the first step to stratify forestland into broad forest types. A modelling chain linking FI plots to airborne and spaceborne LiDAR was then developed to circumvent the scarcity of field data in the region. The developed models allowed the estimation of forest attributes in thousands of surrogate FI plots corresponding to spaceborne LiDAR footprints distributed across the project area. The surrogate plots were used as a reference dataset for estimating each forest attribute in each 30 m forest cell within the project area. The estimation was based on the k-nearest neighbour (k-NN) algorithm, where the selection of the four most similar surrogate FI plots to each cell was based on satellite, topographic, and climatic data. Wall-to-wall 30 m raster maps of broad forest type, stand height, crown closure, stand volume, total volume, aboveground biomass, and stand age were created for a ~400,000 km2 area, validated with independent data, and generalized into a polygon GIS layer resembling a traditional FI map. The MVI project showed that a reasonably accurate FI map for large, remote, predominantly non-inventoried boreal regions can be obtained at a low cost by combining limited field data with remote sensing data from multiple sources.
Plain Language Summary
A forest inventory map shows the location and characteristics of different types of forests in a region. This information is usually derived from visual interpretation of aerial photographs, but this method is impractical across large inaccessible areas such as in the Northwest Territories (NWT). To tackle this problem, the Multisource Vegetation Inventory (MVI) was started in 2005 and completed recently; its development and results are described in this paper. The MVI project combined multiple sources of remote sensing data from both planes and satellites to map 400,000 km2 of forests in the NWT. Fine-detail maps of stand height, crown closure, stand volume, total volume, aboveground biomass and stand origin were produced and a detailed accuracy assessment was undertaken. The MVI project showed that a reasonably accurate forest inventory map for large, remote, predominantly non-inventoried boreal regions can be obtained at a low cost by combining limited field data with remote sensing data from multiple sources.
