BIOTERRAIN MAPPING
The Wildlife Branch of the British Columbia Ministry of Environment produces many forms of ecologically-based maps, such as habitat maps, wildlife capability and suitability maps, fire and habitat management maps, and others. In most cases, a terrain or soil map forms the basis of these biophysical maps. The maps also take account of any ecologically significant features that influence the habitat of a species.
In order to subdivide the landscape into ecologically-significant entities, the following characteristics are considered in addition to the usual terrain soil parameters: ecoregion, biogeoclimatic zone, and ecosystem. Some specific ecological features that are considered in the definition of bioterrain polygons, but not included for normal terrain mapping, include: aspect; distinct vegetation boundaries, foreshore characteristics, riparian zones, wetland characteristics, bedrock mineralogy,
Site forms for bioterrain mapping include the following characteristics in addition to those recorded for normal terrain mapping: aspect, soil (pedological) classification (subgroup); soil phase, site position (macro, meso), site surface shape, microtopography, site diagram, exposure type, ecological moisture regime, slope position (shedding, normal, receiving, holding), soil drainage, perviousness, free water, depth to water table, effective rooting depth, root restricting layer, frozen layer, carbonate, salinity, humus form class, description of decaying wood. Soil description forms are also completed for each site.
The methodology for bioterrain mapping is evolving rapidly, as mappers endeavour to develop criteria for recording significant habitats. Schemes for detailed mapping of cliffs and talus, and avalanche fans and chutes have recently been developed. Mapping parameters and criteria for soil biodiversity, glacial refugia, bedrock weathering and shallow soils, and hydrologic features such as ephemeral streams, bogs and ponds are being investigated.
see Standards for Terrestrial Ecosystems Mapping of British Columbia, Resources lnventory Committee.
(From unpublished notes by R. Maxwell, Wildlife Branch, BC Ministry of Environment, Lands and Parks, 780 Blanshard Street, Victoria, BC.)