中文摘要：

以7种不同预处理（T1~T7）麦秸改良土壤为试验数据,选用150 min累积入渗量（I150）、有效含水率（θ）、土壤累积蒸发量（Ec）、土壤团聚体分形维数（FD）、土壤孔隙分形维数（Dp）、秸秆分解率（Rd）、全氮含量（wTN）7个相互独立的指标,基于主成分分析方法研究不同预处理秸秆还田后,对土壤入渗特性、土壤水分有效性、持水性、结构稳定性、土壤孔隙、秸秆分解率、土壤全氮含量7个方面的改良土壤效果进行评价。将各评价指标的加权和作为改良土壤效果的综合主成分指标。结果表明,改良效果综合主成分可以代表86.93%的不同预处理麦秸改良效果变异信息,且服从正态分布,具有较好的代表性和客观性,可以用于预处理麦秸改良土壤效果的评价。在7个指标中,第一公因子以全氮含量（wTN）、孔隙分形维数（Dp）、土壤团聚体分形维数（FD）、土壤有效含水率（θ）的贡献率较大（达49.92%）;第二公因子以秸秆分解率（Rd）、累积入渗量（I150）和土壤累积蒸发量（Ec）的贡献率较大（达37.01%）。不同预处理秸秆改良土壤综合效果优劣依次为T6、T7、T3、T5、T4、T2、T1。氨化秸秆对土壤的综合改良效果优于未氨化秸秆,粉碎秸秆对土壤的综合改良效果优于未粉碎秸秆,氨化秸秆与硫酸钙改良剂混合还田的土壤改良效果优于与硫酸铝改良剂混合配施措施。

英文摘要：

In order to find optimal pretreated wheat straw utilization on soil improvement,soil samples were collected from indoor incubation experiment of different wheat straw utilizations,seven separate indicators,including 150 min of cumulative infiltration（ I150）,available soil water content（ θ）,cumulative evaporation（ Ec）,soil aggregate fractal dimension（ FD）,soil pore fractal dimension（ Dp）,straw decomposition rate（ Rd） and total nitrogen（ wTN）,were chosen to evaluate the effect of different pretreated wheat straw utilizations on soil improvement（ e. g.,water infiltration capacity,soil moisture availability,water-holding capacity,structural stability,soil porosity,straw decomposition rate and soil total nitrogen content）. The principle component analysis method was used to conduct the above mentioned seven indicators,then comprehensive improvement index of soil improvement of wheat straw utilization was established by weighted sum of different evaluation indices. Result showed that comprehensive improvement quality principle component obeyed normal distribution significantly and had good representation and objectivity,which could include 86. 93% primordial quality attribute variationinformation,so it could be used as the overall pretreated wheat straw utilization improvement evaluation index of the seven indicators,wTN,Dp,FDand θ contributed the largest percentage（ 49. 92%） in the first common factor,while Rd,I150 and Eccontributed the most（ 37. 01%） in the second common factor.The treatments order of wheat straw utilization improvement was T6〉 T7〉 T3 〉T5 〉T4 〉T2〉 T1.Comprehensive soil amendment of ammoniated straw was better than that of non-ammoniated straw,comprehensive soil amendment of pulverized straw was better than that of non-pulverized straw,ammoniated straw mixed with calcium sulphate improver was better than that of mixed with aluminum sulfate improver.