Mapping and quantification of planted tree and shrub shelterbelts in Saskatchewan, Canada

摘要

The Government of Canada's farm assistance programs have affected > 80 % of Canada's agricultural land base. One important program in the Prairie Provinces was the prairie shelterbelt program (PSP). A significant aspect of the PSP was shelterbelt tree planting to protect farmyard infrastructure and reduce soil erosion. The main goal of this paper was to map historical shelterbelt establishment, total expected shelterbelt length, and total expected number of six common planted shelterbelt species: caragana (Caragana arborescens), green ash (Fraxinus pennsylvanica), Manitoba maple (Acer negundo), Scots pine (Pinus sylvestris), white spruce (Picea glauca Monch), and hybrid poplar (Populus spp.). A clustering approach was designed to group all agricultural ecodistricts (106 total) into clusters (31 total) based on their similarity in 42 variables within five soil zones of Saskatchewan. Correlations between trees ordered through the PSP and observed shelterbelt length (across 2.1 Mha cumulative study area) were used for shelterbelt probability mapping. Mapping accuracy of planted shelterbelts was 48-86 %. Total shelterbelt length (of any species) ranged from 322 to 45,231 km for (in descending order) dark brown > brown > black > dark gray > gray soil zones. Novel decadal time-lapse maps and species-specific shelterbelt maps were produced to capture the progression of shelterbelt establishment for the first time at a province-wide scale which gave a new perspective, in map format, of the expansive impact of the living legacy of the PSP. Shelterbelt data gaps and high priority clusters of agricultural land in Saskatchewan were identified for future shelterbelt research.