PROFITABILITY OF SOIL AND WATER CONSERVATION IN CANADA - A REVIEW

Canada has had a short-lived and low-key experience with agricultural activity-related resource degradation problems because its agricultura l production potential began to be realized only during the last 100 y ears or so. The problems are nevertheless critical, given the small la ndbase suitable for agriculture and a precarious climate (Dumanski et al.). The bastion of Canadian agriculture in the prairies was opened t o farming only early in the 20th century, but severe drought in the 19 30s combined with farming activities to produce extensive erosion prob lems. More moderate climatic conditions and modified farming practices lessened degradation problems until the reemergence of severe drought conditions in the 1980s. Heightened concerns about degradation are as sociated with organic matter depletion, wind and water-borne erosion, and rising salinity resulting primarily from summer fallowing practice s (Cann et al; Rennie), but also from increasing cultivation of margin al lands, largely instigated by government support programs (Van Koote n and Kennedy). Elsewhere in western Canada, degradation problems are associated with surfeits of livestock manures in southwestern British Columbia, pesticide residues from intensive fruit farming in the Okana gan Valley, and aquaculture wastes in coastal water bodies (Van Kooten and Kennedy).