Soil and crop response to stover removal from rainfed and irrigated corn

Abstract

Excessive corn (Zea mays L.) stover removal for biofuel and other uses may adversely impact soil and crop production. We assessed the effects of stover removal at 0, 25, 50, 75, and 100% from continuous corn on water erosion, corn yield, and related soil properties during a 3-year study under irrigated and no-tillage management practice on a Ulysses silt loam at Colby, irrigated and strip till management practice on a Hugoton loam at Hugoton, and rainfed and no-tillage management practice on a Woodson silt loam at Ottawa in Kansas, USA. The slope of each soil was <1%. One year after removal, complete (100%) stover removal resulted in increased losses of sediment by 0.36-0.47 Mg ha À1 at the irrigated sites, but, at the rainfed site, removal at rates as low as 50% resulted in increased sediment loss by 0.30 Mg ha À1 and sediment-associated carbon (C) by 0.29 kg ha À1. Complete stover removal reduced wet aggregate stability of the soil at the irrigated sites in the first year after removal, but, at the rainfed site, wet aggregate stability was reduced in all years. Stover removal at rates ≥ 50% resulted in reduced soil water content, increased soil temperature in summer by 3.5-6.8°C, and reduced temperature in winter by about 0.5°C. Soil C pool tended to decrease and crop yields tended to increase with an increase in stover removal, but 3 years after removal, differences were not significant. Overall, stover removal at rates ≥50% may enhance grain yield but may increase risks of water erosion and negatively affect soil water and temperature regimes in this region.Keywords: stover removal, water erosion, soil aggregation, soil carbon, irrigation IntroductionThe demand for corn stover feedstock for bioenergy production and other competing uses is expected to increase in the near future. Corn stover has been identified as a prime feedstock for bioenergy production in the United States because of its perceived abundance and availability (Wilhelm et al., 2004; United States Department of Agriculture, 2010). Although the use of corn stover for bioenergy production and other expanded uses appears to be feasible, the magnitude at which different levels of stover removal affect soil erosion, soil properties, crop production, and other ecosystem services is not well understood in the western Corn Belt in general and Kansas in particular. This information is needed for determining the amount of stover that can be harvested for biofuel from rainfed and irrigated conditions.Removal of stover for bioenergy may negatively affect ecosystem services provided by crop residues such as erosion control (Cruse & Herndl, 2009). Even soils under no-till management may be affected if residues are removed at high rates. On silt loam and sandy loam no-till soils in Iowa, Laflen & Colvin (1981) found that a decrease in stover cover resulted in an exponential increase in sediment loss. On a silt loam in Illinois, 100% stover removal resulted in increased sediment loss from 0.1 to 1.3 Mg ha À1 (Bradford & Huang, 1994).Differences in s...

Impacts of Corn Residue Grazing and Baling on Wind Erosion Potential in a Semiarid Environment

“…Reduced residue cover in baled and grazed plots may have also increased fluctuations in soil temperature. While we did not monitor changes in soil temperature in this study, another study in a similar region (western Kansas) found that residue removal >50% increased the soil temperature by about 2°C in spring (Kenney et al, 2015). The same study found that the amplitude of daytime and nighttime soil temperatures in plots with limited or no residue cover in winter and spring was larger than in plots with high residue cover.…”

Visual Soil Structure Effects of Tillage and Corn Stover Harvest in Iowa

“…Under high stover harvest, NT had a Sq of <3 in the top layer and a Sq of >3 in the bottom layer for CP and NT, respectively. The Sq of >3 in the CP top layer suggests that risks of soil erosion are likely increased due to the absence of soil cover as shown by Kenney et al (2015). The Sq scores in CP and NT were influenced by corn stover harvest at both layers.…”

“…Several studies have shown that stover harvest can have negative impacts on near-surface soil structure and physical properties Lal, 2008, 2009b;Osborne et al, 2014;Jin et al, 2015). The impacts of stover harvest have generally been assessed through classical soil physical measurements, such as soil bulk density, penetration resistance, aggregate stability, percentage macroaggregation, aggregate tensile strength, infiltration, hydraulic conductivity, air permeability, and soil water retention (Karlen et al, 1994;Blanco-Canqui et al, 2006, 2009bMoebius-Clune et al, 2008;Kenney et al, 2015;Wegner et al, 2015). Those soil properties were chosen because of their indirect relationship to soil structure, but they require substantial methodological expertise and demand tedious sampling and sophisticated laboratory analyses .…”

Corn Belt soil carbon and macronutrient budgets with projected sustainable stover harvest

“…Varvel and Wilhelm (2008) suggested that a stover yield of 6.0 Mg ha À1 is required to maintain SOC levels in the western Corn Belt. Kenney et al (2013) assessed the effects of stover removal at 0, 25, 50, 75, and 100% from continuous corn on water erosion, corn yield, and related soil properties during a 3-year study under various management practices on different soil types in Kansas. They observed that stover removal at rates !50% enhanced grain yield but increased risks of water erosion and negatively affected soil water and temperature regimes in this region.…”

“…However, excessive removal of stover could adversely impact soil fertility and productivity (Varvel and Wilhelm, 2008;Tan et al, 2012;Kenney et al, 2013). With an increasing demand for crop residue as biofuel feedstock, balancing residue harvest and nutrient budgets to achieve sustainable crop production and soil fertility is becoming increasingly important.…”