Management practices effects on soil carbon dioxide emission and carbon storage

Authors: Sainju, Upendra

Submitted to: Natural Resources Research Update (NRRU)
Publication Type: Research Technical Update
Publication Acceptance Date: 2/16/2010
Publication Date: 2/16/2010
Citation: Sainju, U.M. 2010. Management practices effects on soil carbon dioxide emission and carbon storage. Natural Resources Research Update (NRRU). Update #252266.

Interpretive Summary:

Technical Abstract: Management practices can influence soil CO2 emission and C content in cropland, which can effect global warming. We examined the effects of combinations of irrigation, tillage, cropping systems, and N fertilization on soil CO2 flux, temperature, water, and C content at the 0 to 20 cm depth from May to November 2005 at two sites in the northern Great Plains. Treatments were two irrigation systems (irrigated vs. non-irrigated) and six management practices that contained tilled and no-tilled malt barley with 0 to 134 kg N ha-1, no-tilled pea, and a conservation reserve program planting applied in Lihen sandy loam (sandy, mixed, frigid, Entic Haplustolls) in western North Dakota. In eastern Montana, treatments were no-tilled malt barley with 78 kg N ha-1, no-tilled rye, Austrain winter pea, no-tilled fallow, and tilled fallow applied in dryland Williams loam (fine-loamy, mixed Typic Argiborolls). Tillage increased CO2 flux by 62 to 118% compared with no-tillage at both places. The CO2 flux was 1.5 to 2.5-fold greater with tilled than with non-tilled treatments following heavy rain or irrigation in North Dakota and 1.5 to 2.0-fold greater with crops than with fallow following substantial rain in Montana. Nitrogen fertilization increased CO2 flux by 14 % compared with no N fertilization in North Dakota and cropping increased the flux by 79% compared with fallow in no-till and 0 kg N ha-1 in Montana. The CO2 flux in undisturbed CRP was similar to that in no-tilled crops. The CO2 flux was linearly related with soil temperature and daily average air temperature at the time of CO2 measurement. Soil organic and inorganic C contents were not influenced by treatments. Although soil C storage was not altered, management practices influenced CO2 flux within a short period due to changes in soil temperature, water content, and nutrient levels (Sainju et al., 2008). Regardless of irrigation, CO2 flux can be reduced from croplands to a level similar to that in CRP planting using no-tilled crops with or without N fertilization compared with other management practices (Sainju et al., 2008). No-tillage significantly reduced CO2 emission compared with conventional tillage (Jabro et al., 2008). Publications contributing to the NRRU Release as shown above: 1. Sainju, U.M., J.D. Jabro, and W.B. Stevens. 2008. Soil carbon dioxide emission and carbon sequestration as influenced by irrigation, tillage, cropping system, and nitrogen fertilization. J. Environ. Qual. 37:98-106. 2. Jabro, J.D., U.M. Sainju, W.B. Stevens, and R.J. Evans. 2008. Carbon dioxide flux as affected by tillage and irrigation in soil converted from perennial forages to annual Crops For more information contact Dr. Upendra Sainju ([e-mail])