不同秸秆添加量对秸秆碳在黑土团聚体中固存的影响  

Sequestration of Straw Carbon in Aggregates of Black Soil with Different Amounts of Straw Addition

作　　者：徐香茹 黄兴羽 靳洁 周子彪 张久明[2] 汪景宽[3] XU Xiang-ru;HUANG Xing-yu;JIN Jie;ZHOU Zi-biao;ZHANG Jiu-ming;WANG Jing-kuan(College of Agricultural Engineering,Jiangsu University,Zhenjiang 212013,China;Heilongjiang Academy of Agricultural Sciences,Harbin 150001,China;College of Land and Environment,Shenyang Agricultural University,Key Laboratory of Northeast Arable Land Conservation,Ministry of Agriculture/National Engineering Research Center for Efficient Utilization of Soil and Fertilizer,Shenyang 110866,China)

机构地区：[1]江苏大学农业工程学院,江苏镇江212013 [2]黑龙江省农业科学院,黑龙江哈尔滨150001 [3]沈阳农业大学土地与环境学院/农业农村部东北耕地保育重点实验室/土肥高效利用国家工程研究中心,辽宁沈阳110866

出　　处：《土壤通报》2024年第6期1628-1635,共8页Chinese Journal of Soil Science

基　　金：国家自然科学基金(42307428);国家博士后面上项目(2021M691316);黑龙江省省属科研院所科研业务费项目(CZKYF-1-B006)。

摘　　要：【目的】秸秆还田是加快农业废弃物资源化利用和增加土壤碳储量的合理有效措施。但关于秸秆添加后,秸秆碳在黑土团聚体中的固定和转化过程尚不十分清楚。【方法】本研究将^(13)C标记秸秆按照不同比例(1%、3%、5%和10%)添加到低肥力和高肥力水平的黑土中,在田间原位培养360 d。通过分析黑土团聚体组分有机碳含量的动态变化,研究土壤原有机碳和秸秆碳在不同团聚体组分中的转运特征,揭示土壤有机碳的固定过程。【结果】与不添加秸秆处理相比,3%以上秸秆添加量分别使低肥力和高肥力土壤有机碳含量显著增加了21.00%~81.81%和12.40%~44.00%。与低肥力土壤添加秸秆处理相比,高肥力土壤大团聚体比例增加了10.3%~21.3%。培养360 d,高肥力土壤与低肥力土壤相比,大团聚体有机碳含量平均增加了11.4%。10%秸秆添加量处理下高肥力和低肥力土壤与不添加秸秆处理相比分别显著提高了土壤微团聚体组分有机碳含量36%和67%。随培养时间增加,大团聚体中秸秆碳占有机碳的比例逐渐降低,而微团聚体(53~250μm)和黏粉粒组分(<53μm)中秸秆碳占比逐渐增加。【结论】随着秸秆分解,秸秆碳从大团聚体逐渐向较小粒级团聚体运转和积累。高肥力黑土添加秸秆后,黏粉粒组分有机碳含量趋于稳定状态。[Objective]Returning straw to the field is a reasonable and effective measure to accelerate the utilization of agricultural waste as resources and to increase the storage of soil organic carbon(C).However,the stabilization and transformation process of straw C in different aggregates fractions of Black soils was not very clear.[Method]The ^(13)C-labeled straw treatments(as percentages of 1%,3%,5% and 10%)were added to low and high fertility levels of Black soil,and then they were incubated in-situ for 360 days.This paper analyzed the dynamic changes of organic C of aggregate fractions,and studied the transportation characteristics of native organic C and straw-C in aggregate fractions,in order to reveal the sequestration process of soil organic C.[Result]Compared with the treatment without straw addition,more than 3% of straw addition treatments significantly increased the organic C contents of low and high fertility soils by 21.00% to 81.81% and 12.40% to 44.00%,respectively.Under the high fertility soil,the proportions of macro-aggregate fraction in soil were increased by 10.3 to 21.3% relative to the low fertility soil with the straw addition treatments.At the end of incubation,the average organic C content of macro-aggregate fractions was increased by 11.4% in high fertility soil compared with low fertility soil.Compared with the no straw addition treatment,10% of straw addition significantly increased the content of organic C in soil microaggregate fraction in the low and high fertility soils by 36% and 67%,respectively(P<0.05).The contribution percentage of straw C to total organic C in macro-aggregate fraction was decreased gradually,while that in microaggregate(53~250μm)and sit and clay fraction(<53μm)were gradually increased in soils with varied amount of straw addition after 360 days of incubation.[Conclusion]As the straw decomposition,straw C gradually was transported and accumulated from macro-aggregate fraction to smaller size aggregate fractions.The organic C content of silt and clay fraction in h

关 键 词：秸秆添加量 ^(13)C标记 有机碳周转 团聚体组分 

分 类 号：S753.5[农业科学—森林经理学]