SummaryThe North China Plain (NCP) is an important agricultural area, where conventional tillage (CT) is used year-round. However, long-term CT has damaged the soil structure, threatening agricultural sustainability. Since 2002, we have conducted a long-term tillage experiment in the NCP to explore the effects of different types of tillage on soil and crop yield. As part of long-term conservation tillage, we conducted a 2-year study in 2016/2017 to determine the impact of no tillage (NT), subsoiling (SS), rotary tillage (RT) and CT on soil aggregate distribution, aggregate-associated organic carbon (AOC), aggregate-associated microbial biomass carbon (AMBC), and maize yield. Compared to CT, NT increased the content of macro-aggregates (+4.8%), aggregate-AOC (+8.3%), and aggregate-AMBC (+18.3%), but decreased maize yield (−11.5%). SS increased the contents of macro-aggregates (+5%), aggregate-AOC (+14.7%), and aggregate-AMBC (+16%); although the yield increase was not significant (+0.22%), it had the highest economic benefit among the four tillage measures. RT had no significant advantage when considering the above soil variables; moreover, it reduced maize yield by 16.1% compared with CT. Overall, SS is a suitable tillage measure to improve soil macro-aggregate content, carbon content, yield, and economic benefit in the NCP area.

中文翻译：

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由于长期保护性耕作，华北地区玉米产量和土壤聚集体相关碳增加

摘要华北平原（NCP）是一个重要的农业区，全年使用常规耕作（CT）。然而，长期 CT 破坏了土壤结构，威胁到农业的可持续性。自 2002 年以来，我们在华北地区进行了长期耕作试验，以探索不同耕作方式对土壤和作物产量的影响。作为长期保护性耕作的一部分，我们在 2016/2017 年进行了一项为期 2 年的研究，以确定免耕 (NT)、深松 (SS)、旋耕 (RT) 和 CT 对土壤团聚体分布、团聚体-相关有机碳 (AOC)、聚集体相关微生物生物量碳 (AMBC) 和玉米产量。与 CT 相比，NT 增加了宏观骨料 (+4.8%)、骨料-AOC (+8.3%) 和骨料-AMBC (+18.3%) 的含量，但降低了玉米产量 (-11.5%)。SS 增加了宏观骨料 (+5%)、骨料-AOC (+14.7%) 和骨料-AMBC (+16%) 的含量；虽然增产幅度不大（+0.22%），但在四种耕作措施中经济效益最高。在考虑上述土壤变量时，RT 没有显着优势；与CT相比，玉米减产16.1%。总体而言，SS是提高华北地区土壤宏观团聚体含量、碳含量、产量和经济效益的适宜耕作措施。