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Tillage management is a direct factor in affecting soil quality, which is a key factor in sustainable agriculture. However soil quality evaluation needs significant manpower, material resources and time. To explore the sensitive indicators of soil quality affected by tillage management, eight soil physical and chemical properties under three tillage managements, including plow tillage, subsoiling tillage and rotary tillage, were determined under a long-term experiment in North China Plain. The results showed that subsoiling tillage management had the highest soil organic carbon and total nitrogen in the 0–20 cm layer and the lowest soil bulk density in the 30–40 cm layer. Rotary tillage management had the highest soil water content in the 0–40 cm layer. Meanwhile, compared to 2002, the soil organic carbon, total nitrogen and soil bulk density had varied greatly in 2012, but there was no significant difference between 2012 and 2018. However, other property concentrations tended to increase in 2002, 2012 and 2018. In addition, there was a significant linear relationship between soil quality index and grain yield. Subsoiling tillage management had the highest soil quality index and gain yield both in 2012 and 2018. The soil quality can be evaluated through the sensitive indicator of soil organic carbon, total nitrogen, soil bulk density, total phosphorus and soil water content, which provides a scientific basis for selecting reasonable tillage management and evaluating soil quality in this agricultural production area or other similar areas. [ABSTRACT FROM AUTHOR]

Reasonable tillage management benefits soil structure optimization and agricultural sustainability. However, the differences of immediate (i.e. changes between post- and pre- tillage) and long-term effects (i.e. changes between treatments after certain years) under different tillage practices is often neglected. This study involved a 16-year field experiment including three tillage practices (plow tillage, PT; subsoiling tillage, ST and rotary tillage, RT) and two crop residue management practices (no residue return and all residue return). Those immediate and long-term effects on soil physical properties and soil organic carbon were investigated. For the immediate effects after tillage, the soil water storage under PT, ST, and RT decreased by 5.8%, 4.0%, and 3.2%, respectively; while those under residue return and no residue return decreased by 3.9% and 4.6%, respectively. Under the same conditions, ST was more beneficial to reduce soil penetration resistance. The soil bulk density post-tillage was significantly lower than that pre-tillage at 0–10 cm soil depth, meanwhile the soil bulk density at 10–40 cm soil depth was generally decreased after tillage practice under ST treatment. For the long-term effects, the penetration resistance at 10–50 cm soil depth and the soil bulk density at 10–30 cm soil depth were lower under the ST treatment than those under PT and RT treatments. Additionally, residue return was beneficial for soil water storage, soil bulk density, and soil organic carbon storage. Overall, both for the immediate and long-term effects, subsoiling tillage with residue return significantly increased soil water storage, total porosity, soil organic carbon storage and crop yields, while decreased soil bulk density and penetration resistance. • Tillage immediately decreased soil bulk density at a soil depth of 0–10 cm but not at 20–30 cm. • Subsoiling tillage decreased the penetration resistance and soil bulk density for a long time. • Subsoiling tillage had a highest SOC storage with a higher soil water storage. • Subsoiling tillage with residue return was beneficial to stable and increased production. [ABSTRACT FROM AUTHOR]

Appropriate tillage plays an important role in mitigating the emissions of greenhouse gases (GHG) in regions with higher crop yields, but the emission situations of some reduced tillage systems such as subsoiling, harrow tillage and rotary tillage are not comprehensively studied. The objective of this study was to evaluate the emission characteristics of GHG (CH4 and N2O) under four reduced tillage systems from October 2007 to August 2009 based on a 10-yr tillage experiment in the North China Plain, which included no-tillage (NT) and three reduced tillage systems of subsoil tillage (ST), harrow tillage (HT) and rotary tillage (RT), with the conventional tillage (CT) as the control. The soil under the five tillage systems was an absorption sink for CH4 and an emission source for N2O. The soil temperature positive impacted on the CH4 absorption by the soils of different tillage systems, while a significant negative correlation was observed between the absorption and soil moisture. The main driving factor for increased N2O emission was not the soil temperature but the soil moisture and the content of nitrate. In the two rotation cycle of wheat-maize system (10/2007–10/2008 and 10/2008–10/2009), averaged cumulative uptake fluxes of CH4 under CT, ST, HT, RT and NT systems were approximately 1.67, 1.72, 1.63, 1.77 and 1.17 t ha−1 year−1, respectively, and meanwhile, approximately 4.43, 4.38, 4.47, 4.30 and 4.61 t ha−1 year−1 of N2O were emitted from soil of these systems, respectively. Moreover, they also gained 33.73, 34.63, 32.62, 34.56 and 27.54 t ha−1 yields during two crop-rotation periods, respectively. Based on these comparisons, the rotary tillage and subsoiling mitigated the emissions of CH4 and N2O as well as improving crop productivity of a wheat-maize cropping system. [ABSTRACT FROM AUTHOR]