Long-Term Temporal Trends in Agri-Environment and Agricultural Land Use in Ontario, Canada: Transformation, Transition and Significance

To help ground agri-environmental policy in evidence, long-term trends in agri-environmental and agriculturalland use data in Ontario, Canada (1826-2011, 1921-2011) were identified using correlation and trend detection(Mann-Kendal test) and compared to other parts of Canada and other developed countries. After historicexpansion 1826-1931, farm area decreased 1931-2011 by 4 million ha or 44.5%, similar to decreases in easternCanada, eastern US and other developed countries, but contrasting continued but slowing expansion in westernCanada. Ontario crop area varied little 1921-2011, but with large shifts in crop types and production increases.Crop area in eastern Canada was declining or stable, while in western Canada continued increasing. Majorchanges 1921-2011 included significant declining pasture area (-78.7%), hay area (-44.9%) and cattle numbers(-33.9%), along with increases in soybean and corn area and in chicken and hog numbers-transforminglandscapes, similar to trends in eastern Canada but contrasting western Canada. Two periods of change areidentified using principal components analysis, 1921-1970s, a long modernization period (69.1% of variance)and the 1970s-2011 period (20.1% of variance), with decreases in cattle numbers, hay and pasture and increasesin hogs, chickens, soybeans, corn and wheat. After the 1970s, agri-environmental stewardship increased, andsome environmental risks decreased with reduced pesticide use (-45%, 1983-2008), phosphorus fertilizer use(-30.1%, 1981-2011) and estimated manure volumes (-42.6%, 1976-2011). Illustrating the regional diversity ofagricultural change, Ontario trends are unique, differing considerably from western Canada, but having somesimilarities with other eastern provinces, the mid-west and eastern US and many other developed countries. Theresearch emphasizes the need to base agri-environmental policy in sound empirical trend analysis.