Improving soil physical properties is important to soil conservation. Cover cropping can improve soil physical properties and organic matter content which can reduce soil loss, and thereby improve land productivity and environmental quality. In this article, the benefits of cover crops (CCs) for improving soil physical and hydraulic properties are reviewed as well as some soil conservation benefits that might accrue. The review indicates that CCs reduce soil bulk density by approximately 4%, increase macropores by approximately 33%, and increase water infiltration by as much as 629%, as compared to soil with no CCs. These improvements have been reported to lead to as much as 96% reduction in soil loss. Some current knowledge gaps in understanding how CCs can improve soil physical properties have been identified, including identifying which biomass, aboveground or belowground biomass, plays a greater role in organic C accumulation. Future research should focus on the interconnectedness of soil pores generated by CCs and the influence of CCs on heat transport parameters to further improve soil physical properties and associated benefits.

Research results still vary, especially between locations, on the effects of agricultural practices on soil chemical properties and crop yield, and not all reasons for the variation are fully understood. Thus, this study investigated the influence of tillage, cover crop and crop rotation management practices on selected soil chemical properties. The study was conducted on a silt-loam soil in central Missouri during the 2011 to 2013 growing seasons. The soil was managed by moldboard plow tillage at two levels (tillage [till] vs. no-tillage [NT]). Cover crop management included cereal rye (Secale cereale) at two levels (cover crop [CC] vs. no cover crop [NC]). The main crops that were grown were a corn (Zea mays L.) and soybean (Glycine max L.) rotation. The soil samples were collected each year at 0–10 cm, 10–20 cm, 20–40 cm and 40–60 cm depths for the analysis of soil chemical properties. The results showed that after 3 years of study, the relative increase in percent soil organic matter (OM) was 4% under the no-till management as compared with moldboard plow tillage. In addition, the relative change in the percentage of OM was 8% greater in the CC management compared with NC. Furthermore, the results show a significant improvement (p = 0.0304) in total carbon with a combination of no-till management and a corn/soybean rotation as compared with continuous corn and soybean. The interaction effects of the management practices on the soil chemical properties were difficult to predict throughout the study.

Water is usually the most limiting factor in agricultural grain crop production. Various agricultural management practices, such as tillage and use of cover crops, have the potential to influence water infiltration into soil. This study was conducted on a Waldron silt loam (fine, smectitic, calcareous, mesic Aeric Fluvaquents) soil to evaluate the influence of cover crop and tillage management on in situ infiltration. The field site included three replicate blocks in a randomized complete block design with each plot measuring 21.3 m (69.9 ft) length and 12.2 m (40 ft) width. The two treatment factors included cover crop at two levels (cereal rye [Secale cereale] cover crop [CC] versus no cover crop [NC]) and tillage at two levels (moldboard plow tillage [Till] versus no-tillage [NT]). Continuous corn (Zea mays L.) was grown. Infiltration rates were measured in all the treatments using a Mariotte system with single-ring infiltrometers during the 2014 and 2015 growing seasons. Water infiltration parameters were estimated using the Parlange and Green-Ampt infiltration equations. Parlange and Green-Ampt models appeared to fit measured data well with coefficient of variation ranging from 0.92 to 0.99. In 2014, the saturated hydraulic conductivity (K_S) parameter value determined from the Parlange model was 30.4 mm h⁻¹ (1.2 in hr⁻¹) for NT, about 42% greater than Till. The K_S parameter value determined from the Green-Ampt model was 25.9 mm h⁻¹ (1 in hr⁻¹) for NT, about 54% greater than Till. In 2015, the sorptivity (S) parameter value determined from the Parlange model was 38.6 mm h^−0.5 (1.5 in hr^−0.5) for CC, about 82% greater than NC. The S parameter value determined from the Green-Ampt model was 34 mm h^−0.5 (1.3 in hr^−0.5) for CC, about 90% greater than NC. Cover crop management can increase water infiltration, which can improve soil quality and enhance the sustainability of crop production systems.

Cover crops have been known to reduce soil erosion, among other benefits, and increase water infiltration, organic matter and soil microbial activity. This study was conducted at Lincoln University's Freeman farm during 2011 and 2012 to assess the effects of cover crop management on soil physical and biological properties. The soil of the experimental site was a Waldron silt loam soil (Fine, smectitic, calcareous, mesic Aeric Fluvaquents). The field was 4.05ha in size and subdivided into 48 plots, each measuring 12.2 m x 21.3 m. The cropping pattern for the plots was a corn (Zea mays L.)/soybean (Glycine max) rotation. The cover crop of choice was cereal rye (Secale cereale). Half of the total plots had cover crop management while the other half had no-cover crop. Soil samples were collected at four depths; 0-10, 10-20, 20-40 and 40-60cm. Samples were oven dried at 105oC for 72h for soil physical properties analysis. Air dried soil samples were also sent to a commercial laboratory for analysis of soil biological properties. Results showed a significant effect (p< 0.05) of cover crop on the selected soil physical and biological properties. A 3.5% decrease was also observed in soil bulk density in cover crop plots as compared with no-cover crop plots. The carbon to nitrogen (C/N) ratio decreased with increasing sampling depth for the first three depths and increased slightly in the fourth depth (p<0.05). C/N ratio also showed a 5.6% increase in no-cover crop plots as compared with cover crop plots. The cover crop used in this study was capable of significantly improving soil physical and biological properties