ECOLOGICALLY-BASED SOIL AND CROP MANAGEMENT SYSTEMS FOR SUSTAINABLE AGRICULTURE
Location: North Central Agricultural Research Laboratory
Title: No-Till Soil Management and the New Vision for Agriculture
Submitted to: Brookings Register
Publication Type: Popular Publication
Publication Acceptance Date: February 21, 2007
Publication Date: February 21, 2007
Citation: Riedell, W.E. 2007. No-Till Soil Management and the New Vision for Agriculture. Brookings Register, February 21, 2007, p.B6.
Interpretive Summary: In an effort to communicate directly with the general public about issues faced by agriculture and farming, this article has been written for publication in the local newspaper, The Brookings Register. A new vision for U.S. agriculture is coming into focus. This new vision is based on expectations that U.S. agriculture will play a major role in helping the country achieve energy independence. Already we have seen increased utilization of corn and soybeans as feedstocks for ethanol and biodiesel production. Just over the horizon is the potential for utilizing biomass crops, such as switchgrass and corn stover, as feedstocks for biofuels. The expanding renewable fuels market is driving a net increase in commodity prices for feedstocks and renewable fuels.
The optimism associated with this new vision for agriculture, however, is balanced by important economic and environmental concerns. A switch to a single crop monoculture in fields that were previously planted using crop rotation will put additional biological limitations on crop yield. Decreased yields and higher production costs could result in decreasing profitability. In addition, harvesting corn stover could lead to a reduction of carbon returned to the soil which could impair the soil microclimate, nutrient cycling, and soil productivity. As science and technology move forward it will be important for agricultural research to not only develop processes for the utilization of agricultural commodities in renewable fuels and co-products, but also to develop efficient and profitable cropping systems that enhance the sustainability of the soil resource. Up until this point in time, producers have done an excellent job in modifying their production systems in response to changing conditions. The success of these adaptations, which have allowed producers to enhance their productivity and profitability, represent an outstanding success story. The challenge for the future is to maintain this success story as we embrace a new vision for agriculture.
What can producers do to adapt their production practices to the changing vision of agriculture as well as the changing local climate? One such change that farmers could consider is no-till soil management. No-till improves water infiltration, decreases runoff, and may even increase the amount of carbon stored in the soil. The importance of soil carbon is that it increases soil health, improves soil water holding capacity, and decreases water evaporation rates. All of these attributes will be increasingly important as we experience climates with higher temperatures and highly variable rainfall during the growing season. Widespread adoption of no-till would help to not only reduce the impact of global climate change on agricultural productivity, but may also help sequester carbon in the soil which in turn may help reduce atmospheric carbon dioxide levels. Soil and cropping systems research conducted in central South Dakota suggests that the adaptation of no-till soil management and the use of diverse crop sequences improves soil resource conservation, crop yield, and interrupts pest cycles. In 2004, the Natural Resources Conservation Service estimated that 5 million acres were planted to no-till in South Dakota. No-till acres were greatest in the region between the Missouri River and the James River. East of the James River and through the Big Sioux River valley, however, the percentage of acres planted using no-till soil management decreases dramatically. What are the constraints that are hindering the wide-spread adoption of no-till in eastern South Dakota? In order to answer this question, understanding the attributes of no-till is necessary. Many of the advantages of no-till production are derived from the crop residue mulch that remains on the soil surface after harvest. Residue mulch protects the soil surface from wind and water erosion, but also delays soil warming in the spring. Cooler soil temperatures translate into slower seed germination, less vigorous early crop growth, and reduced uptake of non-mobile soil nutrients. These factors are especially evident on soils that have low or moderately low internal drainage. Because of the potential positive attributes with the use of diverse crop rotations and no-till soil management on crop productivity and soil resource conservation, research to remove the constraints to widespread adoption of these soil and crop management practices is a priority.