Corn Residue Removal Impact on Topsoil Organic Carbon in a Corn-Soybean Rotation

Abstract

Corn {Zea mays L.) residue is being considered as a feedstock for biofuels production. The impact of removing corn residue on soil productivity is not well understood. A corn-soybean [Glycine max (L.) Merr.] rotation was established in 2000 to determine the effect of removing corn residue at three rates (37, 55, and 98%) on soil organic carbon (SOC) in the 0-to 5-cm layer of soil after 8 yr. The effect of cover crops {slender wheatgrass [Agropyron caninum (L.) Beauv.] In corn and lentil {Lens culinaris Medik. variety Morton) in soybeans} on SOC was also measured. As the rate of residue removal increased, soil organic matter (SOM), wet aggregate stability (WAS), C/N, and microbial activity decreased significantly. Although the effect was not significant, there was a decrease in SOC as the rate of removal increased. At the high residue removal rate, SOM analyzed by quantitative ^^C NMR contained an abundance of aromatic C structures, suggesting that less humified pools of soil C are not being replenished. The humin fraction of the soil had a reduction in SOC under the medium and high rates of residue removal without a cover crop and is likely beginning to be depleted. Bradford-reactive soil protein and immunoreactive soil protein were higher in soils with cover crops, likely due to increased plant diversity and extending the growing season to allocate more C belowground. Overall, the data suggest that the soil properties indicative of soil quality are negatively impacted by removal of corn residue.

Modelling Soil Organic Carbon Changes Under Different Maize Cropping Scenarios for Cellulosic Ethanol in Europe

“…as reported by Powlson et al [32]. In an 8-year field experiment, Stetson et al [4] found that as the rate of residue removal increased, soil organic matter, wet aggregate stability, the C/N ratio and microbial activity decreased significantly.…”

“…However, one aspect that is not often properly considered in the production of biofuels is the depletion of soil organic carbon (SOC) levels that may occur by removing crop residues (and hence carbon input) from cultivated fields [4][5][6].…”

Biological and other soil parameters response to winter cover crops in a mediterranean irrigated system

“…These findings are in agreement with other rotations that included CC (Stetson et al, 2012;Wright and Anderson, 2000) and particularly the ones with grasses (Balota et al, 2014a;Rillig et al, 2002). The glomalin contents showed early increments, therefore, they might be considered also as a sensitive biological parameter.…”

Net Greenhouse Gas Emissions Affected by Sheep Grazing in Dryland Cropping Systems

“…# Total gas flux from May to October + 12% for CO 2 , 15% for N 2 O, and 30% for CH 4 of the total flux from November to April (Liebig et al, 2010) (Tables 4 and 5). It has been known that crop residue removal can reduce soil C storage and C sequestration rates compared with not removing residue (Stetson et al, 2012). Greater C was lost from W-P/B-F than the other cropping sequences, probably due to a smaller amount of belowground crop residues returned to the soil as a result of the absence of crops during fallow.…”