LRES M.S. Thesis Defense: Mary Ellyn DuPre
- Friday, November 20, 2020 at 9:00am
Integrating cover crop mixtures in the Northern Great Plains: An ecological assessment on crop productivity, biodiversity, and temperature and moisture conditions
Cropping systems can impact crop productivity and functioning of the associated biodiversity in the Northern Great Plains, a region which is heavily reliant on low diversity crop rotations and off-farm inputs and is predicted to experience warmer and drier climate scenarios by mid-century. Diversifying agroecosystems through the use of cover crop mixtures is a promising ecologically-based management strategy to stimulate the associated biodiversity and increase sustainability of crop production, but scant research has been conducted in the Northern Great Plains.
The primary goal of this study was to assess the impact of implementing an cover crop mixtures on the associated biodiversity under differing temperature and moisture conditions in a representative dryland agroecosystem of the Northern Great Plains. This knowledge, in turn, could help enhance ecosystem services which may aid crop production. The primary objectives were to 1) assess the impacts of the presence (i.e., cover crop and summer fallow), composition (i.e., two cover crop mixtures differing in richness and planting date), and cover crop termination method (i.e., herbicide, grazing, and haying) on temperature and soil moisture, crop productivity, and weed communities under two temperature and moisture conditions (i.e., ambient, and warmer and drier; 2) examine the effect of cropping system and temperature and moisture conditions on soil and root fungal communities; and 3) assess the effects of cropping system ground beetle (Coleoptera: Carabidae) communities.
Across all studies, we revealed that the presence of cover crops, as well as planting date, composition, and crops termination can all act as subtle ecological filters to weeds, fungi, and ground beetles. We indicated that a 5-species cover crop mixture planted in early-spring can better mediate increases in temperature, suppress weed communities, and enhance fungal and ground beetle communities, compared to summer fallow. Overall, these studies highlighted agronomic and ecological trade-offs that may be addressed in future research.
Meeting number (access code): 120 208 8241
Meeting password: cover crops
- Department of Land Resources and Environmental Sciences