The use of the land suitability rating system to assess climate change impacts on corn production in the lower Fraser Valley of British Columbia

Abstract

The land suitability rating system (LSRS) is a spatial modeling tool that generates a class rating for parcels of land for specific agricultural crops based on a soil–climate–landscape potential. We applied the LSRS module for corn suitability to the agricultural portion of the lower Fraser Valley of British Columbia (BC). We used data from six UN-IPCC AR4 projections covering a range of cold to hot and wet to dry scenarios for the time periods 2010–2039, 2040–2069, and 2070–2099 to assess the impacts of climate change on corn production. To obtain satisfactory spatial results, we linked high-resolution (400 m grid) monthly temperature and precipitation values to the individual polygons of a detailed (1 : 25 000 scale) soil map available for the study area. Of the six future climate scenarios evaluated, the Goddard Institute for Space Studies (GISS_EH-A1B/3) yielded the most favourable results whereby land suitability for corn without irrigation remained relatively stable through the 21st century. Conversely, the Hadley Centre Global Environmental Model (HadGEM-A1B/1) projected a large drop in land suitabililty for corn due to increased climatic and soil moisture deficits. The wide range of climate scenario inputs generated a similarly wide range of LSRS ratings. Most scenarios generated positive impacts for land suitability up to mid-century but negative impacts by late century. Overall, increased heat and aridity will produce earlier harvest dates for corn and likely mean significant changes to the types and timing of crop management practices in the region.