有机物料对原生盐碱土微团聚体特征及稳定性的影响

为了研究不同有机物料对原生盐碱土微团聚体粒径分布状况及不同粒径微团聚体间有机碳含量的影响,以施用有机物料的原生盐碱土为试验对象,设置空白处理(CK)、颗粒状秸秆处理(GW)、正常玉米秸秆处理(CS)、牧草处理(GS)和羊粪处理(SM),采用大田试验与室内分析相结合的方法,研究不同有机物料施用下土壤微团聚体的粒径分布状况及不同粒径微团聚体间有机碳含量,分析不同粒径微团聚体间有机碳对土壤微团聚体稳定性的贡献。结果表明,施用有机物料各处理较CK处理均增加土壤2~0.25mm的团聚体含量,增幅为9.02%~20.37%,其大小排序为GW>SM>GS>CS>CK。对于其他粒径微团聚体分布影响则有所差异。总体来说,有机物料处理增加了土壤大粒径团聚体含量,减少了土壤小粒径团聚体含量。不同有机物料的施用均能增加各粒径土壤微团聚体间有机碳含量。同时,有机物料的施用增加了土壤微团聚体的稳定性,采用回归模型分析、相关分析、冗余分析以及主成分因子分析,表明施用颗粒秸秆更有利于增加土壤微团聚体的稳定性。

Effect of Organic Materials on the Characteristics and Stability of Micro-aggregates in the Native Saline-alkali Soil

In order to study the effect of different organic materials on the distribution of micro-aggregates in native saline soils and the adsorption capacity of different fractional micro-aggregates on organic carbon, the native saline-alkali soils were used as test objects. The field experiment included the control treatment (CK), granular straw treatment (GW), normal corn straw treatment (CS), forage treatment (GS) and sheep manure treatment (SM). Combined with laboratory analysis, the particle size distribution of soil micro-aggregates and the content of organic carbon between different size micro-aggregates were studied. The results showed that the application of organic materials increased the contents of micro-aggregates of 2~0.25 mm in soil compared with CK, with an increase of 9.02%~20.37% and an order of GW > SM > GS > CS > CK. There were some differences in the effects on the micro-aggregates with other particle sizes. In general, organic material application increased the large particle size soil micro-aggregates and reduced the soil micro-aggregates with small particle size. The application of different organic materials could increase the organic carbon content of soil micro-aggregates of various particle sizes. At the same time, the application of organic materials increased the stability of soil micro-aggregates. The regression model analysis, correlation analysis and redundant analysis and principal component analysis were used for factor analysis. The results showed that the application of granular straw was more beneficial to increase the stability of soil microaggregates.