Corn stover harvest and tillage impacts on near-surface soil physical quality

Abstract

and Cherubin, Maurício R., "Corn stover harvest and tillage impacts on nearsurface soil physical quality" (2017). Publications from USDA-ARS / UNL Faculty. 1628Faculty. . http://digitalcommons.unl.edu/usdaarsfacpub/1628 Corn stover harvest and tillage impacts on near-surface soil physical quality Excessive harvest of corn (Zea mays L.) stover for ethanol production has raised concerns regarding negative consequences on soil physical quality. Our objective was to quantify the impact of two tillage practices and three levels of corn stover harvest on near-surface soil physical quality through the Least Limiting Water Range (LLWR). We evaluated no harvest, moderate and high stover harvest treatments within no-tillage and chisel plow plots following seven years of continuous corn production. Forty undisturbed soil samples were taken from the 0-7.5 cm deep layer within each treatment and used to determine water retention curves, soil resistance to penetration and bulk density values (Bd). No-tillage plots had higher average soil bulk density and resistance to penetration values, and were more affected by stover harvest than chisel plow plots. The results confirmed that soil resistance to penetration determined the lower limit of the LLWR regardless of tillage or stover treatment, whereas soil aeration controlled the upper limit only at Bd > 1.45 and Bd > 1.55 Mg m À3 for chisel plow and no-tillage, respectively. The LLWR was smallest for no-tillage with moderate or high corn stover harvest, indicating poor soil physical condition for plant growth, while the largest LLWR occurred with moderate stover harvest and chisel plowing. The introduction of alfalfa (Medicago sativa L.) into an extended rotation with no-tillage improved the LLWR by reducing the potential crop growth restriction due to resistance to penetration. Although bulk density values were only occasionally higher than the critical level (Bd = 1.60 Mg m À3 for chisel plow and Bd = 1.64 Mg m À3 for no-tillage), lower soil structure quality was evident with no-tillage under moderate or high stover harvest and with chisel plowing under high stover removal. The LLWR was more sensitive than available soil water content for detecting tillage and stover harvest effects on soil structural degradation.

Enhancing soil physical quality and cotton yields through diversification of agricultural practices in central Brazil

“…The LLWR was computed following the guidelines described by Wu et al (2003) and used by Tormena et al (2017). SWRC and soil PR curve (SPRC) fittings were done according to the method of Moreira et al (2016) and following the procedure described by Regazzi and Silva (2004).…”

“…The impact of SPQ on plant development is often assessed by using several of the single soil physical indicators (Betioli Júnior et al, 2012;Guimarães, Ball, Tormena, Giarola, & da Silva, 2013;Mukherjee & Lal, 2014). The least limiting water range (LLWR) is an SPQ indicator that integrates water availability, aeration, and soil resistance into a single index, which provides a better understanding of the physical behaviour of a range of soils under different FSs around the world (de Lima, Miola, Timm, Pauletto, & da Silva, 2012;Guimarães et al, 2013;Tormena, Karlen, Logsdon, & Cherubin, 2017). Crops under NT system can overcome the higher soil penetration resistance (PR) than can those under ploughed soils.…”

Crop residue harvest for bioenergy production and its implications on soil functioning and plant growth: A review

“…Structural degradation of soils induced by crop residue harvest is related to decreased macro-aggregation and aggregate stability (Wegner et al, 2015;Johnson et al, 2016), which consequently lead to soil compaction (Wilhelm et al, 2004;Roque et al, 2010). Soil compaction decreases macroporosity and increases mechanical resistance to root penetration (Rosim et al, 2012;Tormena et al, 2017), which decreases water availability to plants (Tormena et al, 2017).…”

“…Moreover, the maintenance of crop residues favors infiltration Johnson et al, 2016;Valim et al, 2016) and storage of water in the soil (Peres et al, 2010;Xiukang et al, 2015;Tormena et al, 2017). Peres et al (2010) observed that the presence of 15 Mg ha -1 of sugarcane straw covering the soil reduced water loss (0-20 cm layer) by approximately half when compared to uncovered soil.…”

“…For instance, Tormena et al (2016) observed through a visual evaluation method that deleterious impacts of high maize stover harvest on soil structural quality were magnified when a chisel plow was used as compared to no-tillage in Iowa (USA). The introduction of alfafa (cover crop) under no-tillage increased the available water and reduced the potential restriction of penetration resistance to crop growth (Tormena et al, 2017). In addition, no-tillage also can mitigate GHG emissions compared to conventional tillage, as reported by Silva-Olaya et al (2013) and Jin et al (2014).…”