秸秆-膨润土-PAM改良材料对沙质土壤团粒结构的影响

Effects of Straw-Bentonite-PAM Improved Material on Sandy Soil Aggregate Structure

为改善沙质土壤团粒结构,以重庆市分布面积较大的冷沙黄泥为研究对象,将作物秸秆、膨润土和聚丙烯酰胺（PAM）按一定比例配制后作为改良材料,研究秸秆改良材料种类、改良材料剂量与配比、土培时间等因素对改良材料改良效应的影响。结果表明：秸秆改良材料可以增加沙质土壤1~5 mm团聚体的含量,不同秸秆改良材料改良效果不同,且随着改良材料剂量、PAM含量（〈2%）的增加、土培时间（〈60 d）的延长,沙质土壤1~5 mm团聚体含量呈现增加趋势;添加麦秆改良材料（添加量为10 g/kg土,配方中PAM含量为2%）的土样,在培养60 d后,1~5 mm团聚体含量为45.1%,为CK的2.12倍,自然条件下的1.9倍,对沙质土壤团粒结构改良效果最为明显。可见,秸秆改良材料可以改善沙质土壤团粒结构。

A simulation experiment was carried out to improve aggregate structure of sandy yellow soil that distributes widely in Chongqing city.We designed the material made of straw,bentonite and PAM and detected its effects on improving the aggregata sturcture of sandy soil.The results indicated that： The proportion of 1~5 mm sandy soil aggregate increased in the presence of improved material,and would be different with different improved material,and also increased with the content of improved material and PAM（2%） and with the cultivated time.In the presence of improved material of wheat straw（the amount was 10 g/kg,the proportion of PAM was 2% and the cultivated time was 60 d）,The proportion of 1~5 mm sandy soil aggregate was 45.1%（2.12 times as the control and 1.9 times as the nature soil）,which showed the best results.