Implications of crop residue removal on soil physical properties: A review

Abstract

AbstractCrop residues are often removed for livestock and biofuel production, but how such removal impacts soil physical properties has not been widely discussed. The objectives of this paper were to discuss: (a) the impacts of crop residue removal on soil physical properties, (b) factors affecting residue removal effects on soils, (c) threshold level of residue removal, (d) strategies to offset the removal negative effects, and (e) research needs. We compiled 66 studies on crop residue removal and soil physical properties published prior to 17 Aug. 2021. Residue removal may not affect bulk density and water infiltration rate but increases penetration resistance by 55% and soil temperature by 1.8 °C in spring. However, it reduces wet aggregate stability by 31%, dry aggregate stability by 44%, and water retention at –33 kPa by 24% in most studies, indicating residue removal can increase erosion risks and reduce soil water storage. Residue removal rate is the leading factor that explains changes in soil physical properties. Residue removal at rates above 50%, in general, adversely affected soil physical properties, which correlates to retaining about 4 Mg ha–1 of residue. Cover crops and manure application may partially offset adverse effects of residue removal on soil physical properties, but studies are too few to make a strong conclusion. Consistency of soil sampling depths, accurate reporting of residue removal rates, and additional data from long‐term experiments are needed. Overall, high rates of residue removal can increase erosion potential and reduce soil water but have mixed impacts on other physical properties.