191-11
Crop Rotation Diversity and Yield Resilience: Evidence from 11 Long-Term Experiments in North America across a Precipitation Gradient.
See more from this Division: ASA Section: Agronomic Production Systems
See more from this Session: Agronomic Production Systems General Oral
Tuesday, October 24, 2017: 11:20 AM
Tampa Convention Center, Room 3
Timothy M. Bowles, Environmental Science, Policy and Management, University of California Berkeley, Berkeley, CA, A. Stuart Grandy, Natural Resources and the Environment, University of New Hampshire, Durham, NH, Francisco J. Calderón, Central Plains Resources Management Research, USDA-ARS, Akron, CO, Michel A. Cavigelli, Sustainable Agricultural Systems Lab, USDA-ARS, Beltsville, MD, Steven W. Culman, School of Environment and Natural Resources, Ohio State University, Wooster, OH, Bill Deen, Department of Plant Agriculture, University of Guelph, Guelph, ON, CANADA, Craig F. Drury, Harrow Research and Development Centre, Agriculture & Agri-Food Canada, Harrow, ON, Canada, Axel Garcia y Garcia, Agronomy and Plant Genetics, University of Minnesota, Lamberton, MN, Amélie CM Gaudin, Department of Plant Sciences, University of California-Davis, Davis, CA, W Scott Harkcom, Plant Science, Penn State University, University Park, PA, R. Michael Lehman, North Central Agricultural Research Laboratory, USDA-ARS, Brookings, SD, Shannon L. Osborne, North Central Agricultural Research Lab, USDA-ARS, Brookings, SD, G. Philip Robertson, W.K. Kellogg Biological Station, Michigan State University, Hickory Corners, MI, Marty R. Schmer, Agroecosystem Management Research Unit, USDA-ARS, Lincoln, NE and Jeffrey S. Strock, Soil, Water and Climate, University of Minnesota, Lamberton, MN
Abstract:
Complex crop rotations that include a diversity of crop functional types are a foundation of sound agricultural management. Farmers have long been aware that crop rotation can help mitigate weed, insect, and pathogen pressure, and that more diverse rotations containing legumes enhance crop yields both with and without high external inputs. Crop yield benefits, however, may be most apparent during adverse weather conditions like droughts and heat waves. The initiation of many long-term experiments comparing crop rotational diversity over the past several decades now provides a unique opportunity to synthesize how crop diversity mediates agroecosystem resilience and derive foundational knowledge of the role of temporal diversity in agricultural systems.
Historical data from 11 long-term grain-based experiments comparing crop rotational diversity that comprise over 300 site-years were obtained. Data include rotations from one to five cash or cover crops and spanned a precipitation gradient from ~400 to ~1100 mm MAP. The objectives were to determine the extent to which more diverse rotations reduce corn yield losses in stressful years, and to determine whether corn yields increase more rapidly over time in more diverse rotations. Hierarchical Bayesian statistical approaches were used to assess these multilevel and longitudinal data. While yield responses to crop rotational diversity vary across sites, the overall response shows that crop rotation diversity provides increased yields in stressful conditions, takes better advantage of favorable conditions, and accelerates yield gains over time. This approach shows the potential of cross-site, large-scale synthesis to reveal foundational knowledge of agricultural production systems, which complement locally-applicable results. Synthesis efforts should increase as long-term agricultural experiment networks and databases that make historical data more accessible are established.
See more from this Division: ASA Section: Agronomic Production Systems
See more from this Session: Agronomic Production Systems General Oral
