Subsoiling increases aggregate-associated organic carbon, dry matter, and maize yield on the North China Plain

Abstract

Background Soil degradation is one of the main problems in agricultural production and leads to decreases in soil quality and productivity. Improper farming practices speed this process and are therefore not conducive to food security. The North China Plain (NCP) is a key agricultural area that greatly influences food security in China. To explore the effects of different tillage measures on aggregate-associated organic carbon (AOC), the accumulation and transport of dry matter, and maize yield, and to identify the most suitable tillage method for use on the NCP, a field experiment was conducted at Shandong Agricultural University from 2016–2017 using plots that have been farmed using conservation tillage since 2002. Methods In this study, Zhengdan 958 summer maize was used as the test material and undisturbed soil and plant samples were obtained under four tillage methods—no-tillage (NT, tillage depth: 0 cm); rotary tillage (RT, tillage depth: 10 cm); conventional tillage (CT, tillage depth: 20 cm); subsoiling (SS, tillage depth: 40 cm)—which were used to determine the AOC and dry matter contents, as well as the yields of two summer maize growing seasons. Each sample was replicated three times and the AOC content was determined via potassium dichromate oxidation colorimetry. Potassium dichromate oxidized organic carbon in organic matter was employed to reduce hexadecent chromium into green trivalent chromium. Colorimetry was then used to determine the amount of reduced trivalent chromium and calculate the organic matter content. Results The resulting data were statistically analyzed and the results showed that, compared with CT, the AOC contents with NT and SS increased by 5.65% and 9.73%, respectively, while that with RT decreased by 0.12%. Conventional tillage resulted in the highest mean dry matter weight when the maize reached maturity, which was 19.19%, 9.83%, and 3.38% higher than those achieved using NT, RT, and SS, respectively. No significant difference was found between CT and SS treatments, both of which tended to increase the accumulation of dry matter as well as its contribution of assimilates to grain yield post-anthesis. Compared with CT, the mean yield increased at a rate of 0.18% with SS, while yields declined at rates of 17.17% and 11.15 with NT and RT, respectively. The yield with NT was the lowest, though the harvest indices with NT and SS were higher than those with RT and CT. Overall, SS increased the accumulation of dry matter and its contribution of assimilates to grain yields post-anthesis, as well as the AOC content and yields, making it the ideal tillage method for the NCP.

Topographic Position, Land Use and Soil Management Effects on Soil Organic Carbon (Vineyard Region of Niš, Serbia)

“…Cervantes et al [78] stated that after the deep plowing, the layer of the deeply plowed fields accumulated 0.4 ± 0.1 Mg SOC ha −1 yr −1 on average. In the study by Shen et al [79], subsoiling was found to increase aggregate-associated organic carbon, dry matter and maize yield on the North China Plain.…”

The effect of deep-tillage depths on crop yield: A global meta-analysis

“…In Europe, a shallow working depth (5-10 cm) was recommended for wheat and barley by Arvidsson et al (2013), but 20-25 cm was also suggested for wheat and barley by Arvidsson (1998). Similar inconsistent situations were observed in Asia, Africa, South America, and Australia (Stibbe and Kafkafi 1973, Adeoye 1982, Barbosa et al 1989, Barber and Díaz 1992, Hammad and Dawelbeit 2001, Kothari et al 2003, Hemmat 2009, Berhe et al 2012, Salem et al 2015, Zeyada et al 2017, Sun et al 2019, Shen et al 2021, Gu et al 2022, the optimum tillage depth ranges from 10 cm to 50 cm for soybean, wheat, and maize under differential countries. Obviously, the optimum tillage depth was highly scattered in differential research, this is presumably largely due to the strongly site-specific effects of tillage depth on crop yields.…”

Research on Strategy Optimization of Green Agricultural Production Trusteeship to Promote Black Land Protection

“…The core of agricultural green development is green agricultural production, which is a production model aimed at energy conservation and emission reduction adopting green agricultural production technologies to achieve sustainable development [17]. Shen et al demonstrated that compared with conventional tillage, the use of subsoiling, no-tillage and other green agricultural production technologies [18] increased the aggregate associated organic carbon in the soil by 9.73%, effectively enhancing the carbon sequestration capacity of the soil [19]. Therefore, agricultural green development is an important support for consolidating the achievements of black land protection.…”