To ascertain the effects of long-term conservation tillage and residue retention on soil organic carbon(SOC) content and aggregate distribution in a deep soil(>20-cm depth) in a dryland environment,this paper analy...To ascertain the effects of long-term conservation tillage and residue retention on soil organic carbon(SOC) content and aggregate distribution in a deep soil(>20-cm depth) in a dryland environment,this paper analyzed the SOC and aggregate distribution in soil, and the aggregate-associated organic carbon(OC) and SOC physical fractions. Conservation tillage(reduced tillage with residue incorporated(RT) and no-tillage with residue mulch(NT)) significantly increased SOC sequestration and soil aggregation in deep soil compared with conventional tillage with residue removal(CT). Compared with CT, RT significantly increased the proportion of small macroaggregates by 23%–81% in the 10–80 cm layer, and the OC content in small macroaggregates by 1%–58% in the 0–80 cm layer. RT significantly increased(by 24%–90%) the OC content in mineral-SOC within small macroaggregates in the 0–60 cm layer, while there was a 23%–80% increase in the 0–40 cm layer with NT. These results indicated that:(1) conservation tillage treatments are beneficial for soil aggregation and SOC sequestration in a deep soil in a dryland environment; and(2)the SOC in mineral-associated OC plays important roles in soil aggregation and SOC sequestration. In conclusion, RT with NT is recommended as an agricultural management tool in dryland soils because of its role in improving soil aggregation and SOC sequestration.展开更多
为充分利用休闲期自然降水，提高旱地麦田土壤的蓄水保墒能力，达到“伏雨春用”的目的，本研究在山西闻喜县旱地麦田将休闲期耕作与覆盖相结合，采用大田试验方法研究了前茬小麦收获后15d 或45d 进行深翻，而后立即采取渗水地膜或液态...为充分利用休闲期自然降水，提高旱地麦田土壤的蓄水保墒能力，达到“伏雨春用”的目的，本研究在山西闻喜县旱地麦田将休闲期耕作与覆盖相结合，采用大田试验方法研究了前茬小麦收获后15d 或45d 进行深翻，而后立即采取渗水地膜或液态地膜覆盖对旱地小麦土壤水分、产量及其构成、品质形成的影响效果，试图探索旱地小麦蓄水保墒技术新途径。结果表明，前茬小麦收获后45 d 深翻较15 d 可显著提高麦收后65 d 至孕穗期100～300 cm 土壤蓄水量，可显著提高播前至孕穗期0～300 cm 总土壤蓄水量，且覆盖的蓄水效果可延续至开花期，以渗水地膜覆盖效果较好。前茬小麦收获后45 d 深翻覆盖较15 d 可显著提高穗数、产量、籽粒蛋白质及其组分含量、籽粒蛋白质产量，且以渗水地膜覆盖效果较好。此外，播前80～200 cm 土壤蓄水量与穗数、产量显著相关；播前和开花期120～300 cm 土壤蓄水量与籽粒蛋白质及其组分含量、籽粒蛋白质产量显著相关，播前80～280 cm 、开花期40～60 cm 、100 cm 、240～300 cm 土壤蓄水量与谷醇比显著相关。总之，休闲期等雨后深翻并采用渗水地膜覆盖有利于提高旱地小麦土壤蓄水量，达到伏雨春用的目的；有利于优化产量结构，提高产量；有利于提高籽粒蛋白质品质，实现优质。展开更多
基金supported jointly by the National Key Research and Development Program of China (2018YFD0200408, 2016YFD0300804)the Science and Technology Project (2015BAD22B03)the Basic Scientific Research Business Expenses of the Chinese Academy of Agricultural Sciences (1610132018024)
文摘To ascertain the effects of long-term conservation tillage and residue retention on soil organic carbon(SOC) content and aggregate distribution in a deep soil(>20-cm depth) in a dryland environment,this paper analyzed the SOC and aggregate distribution in soil, and the aggregate-associated organic carbon(OC) and SOC physical fractions. Conservation tillage(reduced tillage with residue incorporated(RT) and no-tillage with residue mulch(NT)) significantly increased SOC sequestration and soil aggregation in deep soil compared with conventional tillage with residue removal(CT). Compared with CT, RT significantly increased the proportion of small macroaggregates by 23%–81% in the 10–80 cm layer, and the OC content in small macroaggregates by 1%–58% in the 0–80 cm layer. RT significantly increased(by 24%–90%) the OC content in mineral-SOC within small macroaggregates in the 0–60 cm layer, while there was a 23%–80% increase in the 0–40 cm layer with NT. These results indicated that:(1) conservation tillage treatments are beneficial for soil aggregation and SOC sequestration in a deep soil in a dryland environment; and(2)the SOC in mineral-associated OC plays important roles in soil aggregation and SOC sequestration. In conclusion, RT with NT is recommended as an agricultural management tool in dryland soils because of its role in improving soil aggregation and SOC sequestration.
文摘为充分利用休闲期自然降水，提高旱地麦田土壤的蓄水保墒能力，达到“伏雨春用”的目的，本研究在山西闻喜县旱地麦田将休闲期耕作与覆盖相结合，采用大田试验方法研究了前茬小麦收获后15d 或45d 进行深翻，而后立即采取渗水地膜或液态地膜覆盖对旱地小麦土壤水分、产量及其构成、品质形成的影响效果，试图探索旱地小麦蓄水保墒技术新途径。结果表明，前茬小麦收获后45 d 深翻较15 d 可显著提高麦收后65 d 至孕穗期100～300 cm 土壤蓄水量，可显著提高播前至孕穗期0～300 cm 总土壤蓄水量，且覆盖的蓄水效果可延续至开花期，以渗水地膜覆盖效果较好。前茬小麦收获后45 d 深翻覆盖较15 d 可显著提高穗数、产量、籽粒蛋白质及其组分含量、籽粒蛋白质产量，且以渗水地膜覆盖效果较好。此外，播前80～200 cm 土壤蓄水量与穗数、产量显著相关；播前和开花期120～300 cm 土壤蓄水量与籽粒蛋白质及其组分含量、籽粒蛋白质产量显著相关，播前80～280 cm 、开花期40～60 cm 、100 cm 、240～300 cm 土壤蓄水量与谷醇比显著相关。总之，休闲期等雨后深翻并采用渗水地膜覆盖有利于提高旱地小麦土壤蓄水量，达到伏雨春用的目的；有利于优化产量结构，提高产量；有利于提高籽粒蛋白质品质，实现优质。
