LAND USE DISTURBANCE PATTERNS IN A BINARY RECHARGE KARST CATCHMENT: THE EXAMPLE OF NORTHERN VANCOUVER ISLAND’S KINMAN KARST UNIT

Northern Vancouver Island’s Kinman karst unit is typical of other karst units in the region in that its karst catchment has never been delineated. As a result, land use activity planning within the unit has not utilized a total catchment approach to karst management. There is a need to characterize and quantify karst catchment-scale forestry-related impacts such as biophysical damage to karst resources, forest fragmentation, soil loss, alteration of autogenic recharge and the introduction of chemical fire retardants related to a post-harvest wildfire.

A series of maps were produced in a GIS environment showing: 1) the autogenic and allogenic components of the Kinman karst catchment; 2) the spatial extent of the allogenic catchments; 3) the spatial extent of land use-related disturbance within the autogenic and allogenic catchment areas. Satellite imagery was used to refine the spatial extent of a 2014 wildfire within the karst catchment.

The final map products provide a preliminary delineation and characterization of the karst catchment associated with the Kinman karst unit, and to identify the types and spatial extents of land use activities within the karst catchment. The results can be used to guide future management and remediation of the karst. The extent of old growth forest fragmentation on the autogenic portion of the catchment is an urgent concern.