Integration of perennial forage seed crops for cropping systems resiliency in the Peace River region of western Canada

Abstract

The Peace River region is one of the northern agricultural frontiers in Canada, undergoing farmland expansion as well as intensification with input-intensive industrial agriculture. The cropping systems evolved with the rotations between annual grain and perennial forage crops as a prudent adaptation to fragile, crust-forming, runoff-prone, poorly developed, platystructured acidic Luvisolic soils. In recent years, there is a decline in the acreage of perennial forage seed crops leading to simplified low-diversity cropping systems with heavy reliance on external inputs. The production systems have been prone to the rapid evolution of herbicide-resistant weeds, and outbreaks of crop diseases and insect pests in the face of global warming. A number of studies conducted in the Peace River region and other parts of North America have shown multiple benefits of integrating perennial forage crops in the cropping systems. By virtue of high root-to-shoot ratio and perennial growth, forage seed crops can provide multiple ecological services in the fragile Luvisolic soil through increased soil organic matter, carbon sequestration, soil biological diversity, soil structural improvement, nutrient mobilization, crop protection and environmental health, thereby creating conducive effects to the resilient performance of the cropping systems. This review discusses the merits of crop rotations in general and those of perennial forage seed crops in particular in the face of changing climate, with special reference to studies conducted in the Prairies and Peace region of western Canada. Research opportunities are highlighted to elucidate multidimensional ecosystem services from diversified cropping sequences integrating perennial forage seed crops.