Abstract

With the climate changing at a fast rate, the amount of precipitation is predicted to increase and annual temperatures are expected to rise in British Columbia (Province of British Columbia, 2015), diverging towards the two extremes: dry summers for semi-arid regions and wet winters (Agriculture and Agri-Food Canada, 2015). Although projections inherent year-to-year variability and uncertainty in anticipated trends, milder winters could mean longer growing seasons and prevalent pests and pathogens in livestock and crops year-long (Agriculture and Agri-Food Canada, 2015). Heavier fertilizer and pesticide applications will likely result as farmers adapt to changing climate conditions, therefore anticipated precipitation increases on agricultural lands could lead to increasing runoff and this could lead to eutrophication downstream (EPA, 2005). As this could have serious ecological consequences, it is wise to come up with strategies to mitigate the effects of climate change. We want to investigate the Fraser Valley Regional District, one of the heaviest farmed areas in Canada, and identify the agricultural lands in the area that are prone to increasing runoff by using Agricultural Land Reserves (ALR) as a proxy for farmland coverage. We conducted a Weighted Sum, Sensitivity Analysis and Combined Multi-Criteria Evaluation analyses (considering precipitation trend, slope, proximity to streams and lakes, and the Topographic Wetness Index) to identify those areas in the ALR with high risk to runoff. We found a general increase in fall precipitation over the whole study area, and found areas around Agassiz, Laidlaw, and Hope to receive the highest precipitation trends and highest risk scores in all 3 MCE analyses. The results of this project has potential to serve as incentives to change the management of farmed areas at higher risk, such as monitoring the timing of fertilizer and pesticide application; ultimately forming a framework for risk assessment of current ALR regions to climate change and runoff and identifying lower risk areas for potential future expansion of the ALR.