Root Cohesion Table

This resource provides a table of root cohesion values (kPa) to use when reclassifying land use/land cover (LULC) rasters to cohesion rasters. LULC can be acquired from USGS National Land Cover Data (NLCD) based on 2011 Landsat satellite data (USGS 2014b; Jin 2013) and should be grouped into eight generalized categories: water, wetland, snow/ice, barren, herbaceous, shrub/scrub, forest, and developed. The root cohesion rasters can then be used in landslide modeling as parameters needed to create triangle distributions. The distributions will be right skewed, which is typically found in field data (Hammond et al. 1992). Spatially distributed values for root cohesion based on LULC were determined from Schmidt et al. (2001) and other literature, except for barren and developed classifications that were assumed to have few roots and thus, small root cohesion.