Assessing cover cropping options for improved forage yield, quality and soil health in a boreal climate

点击翻译按钮获取中文摘要

Cover crops (CCs) are being integrated into the temperate North American cash crop production systems. However, identification and inclusion of appropriate CC mixtures in cash crop rotation in boreal climate (Newfoundland and Labrador-NL), and their effects on soil physical, chemical and biological properties, nitrogen (N) dynamics and greenhouse gas emission (GHGE) is not known. Boreal climate is characterized as a short growing season and cooler temperature. Cash crops grown in boreal region are generally seeded in first week of June and harvested in 3rd week of October, so very short growing season left after harvest. Interseeding of CC mixture and establishment in cash crops in boreal climate can enhance additional forage production and quality, and improve soil physiochemical and biological properties, and reduce soil erosion and N leaching losses, and eventually GHGE. I will conduct field experiments using different CC mixtures to: 1) assess the forage potential of CC mixtures in silage corn-faba bean rotations, 2) determine the forage yield stability and quality of silage corn and faba bean over 4 years with selected CC mixtures, 3) measure GHGE, soil mineral N dynamics, N leaching, and plant N uptake in CC mixtures in silage corn - faba bean rotation, 4) assess the effects of CC mixtures on soil quality and health (soil organic C and N pools; enzyme activities; and microbial biomass composition, diversity, and abundance). This research program will find suitable CC mixtures that could be successfully grown in short growing season in boreal climate and will provide some additional high quality forage. High quality forage production from CC mixtures will reduce the forage import, carbon footprints, enhance the profitability and self-sufficiency of the livestock and dairy industry and overall feed security in the province which is direly needed. This research program will generate new scientific knowledge for policy makers, federal and provincial government agencies related with agriculture, environment and climate in redefining cropping systems to achieve food security in climate change scenario. Most importantly, it will enhance soil quality and health, reduce soil erosion and will build sustainable and productive forage cover cropping system in boreal climate. This research program will enhance the capacity building of four undergraduate, three master, two PhD students and one PDF in interdisciplinary research (agronomy, plant physiology, soil science, biochemistry, microbiology and hydrology), expertise and skills in designing of the field experiments, employing a range of laboratory and field equipment, data collection, analytical techniques and communication skills to prepare next generation researchers, faculty and industry stakeholders to enhance food security while protecting the environment. Findings will aid in the evolving of novel low-nitrifying and low N2O- cropping systems, with greater impact on society and ecosystems.