油菜绿肥翻压还田对新疆盐碱土壤的改良效果研究

为探讨油菜绿肥翻压对盐碱土的改良效果，在中度盐碱荒地上设置油菜绿肥翻压还田1年（T1）、翻压还田2年（T2）和无绿肥还田（CK）三个处理，研究油菜绿肥对盐碱土壤理化性状、盐组分及棉花产量的影响。结果表明：油菜绿肥翻压的效果表现为T2 > T1 > CK，与CK相比，T2和T1处理分别使棉花籽棉产量增加27.5%和13.5%（P<0.05）；T2处理土壤pH值和电导率比CK分别降低1.0个单位和0.7 mS·cm^-1，T2处理全氮、全磷、全钾和有机质比CK分别增加44.8%、9.1%、6.5%和115.2%；油菜绿肥粉碎还田显著降低盐碱离子含量，其中，与CK相比，T2处理土壤盐基阳离子Ca²⁺、K⁺、Mg²⁺和Na⁺含量显著（P<0.05）降低30.3%、42.7%、41.0%和30.5%，土壤盐基阴离子Cl^-、SO₄^2-、CO₃^2-和HCO₃^-含量显著（P<0.05）降低39.2%、33.0%、32.2%和32.1%。研究表明，油菜绿肥能改善土壤理化性状、增加养分含量、降低盐碱离子含量，对新疆绿洲干旱区盐碱土壤具有较好的改良效果。

Effects of rape green manure returned to field on saline alkali soil improvement in Xinjiang

We investigated the effects of returning rape green manure to field on saline alkali soil improvement in Xinjiang. Moderately saline and alkaline wastelands were subjected to three rape green manure treatments:1 year(T1), 2 years(T2), and no green manure(CK) to elucidate the effects of returning rape green manure on the physical and chemical properties of saline soil, soil salt composition, and cotton yield. The results showed that the effect of returning rape green manure was as follows:T2 > T1 > CK. Compared with CK, T2 and T1 treatments significantly(P<0.05)increased cotton seed yield by 27.5% and 13.5%, respectively. The pH value and conductivity of T2 were 1.0 unit and 0.7 mS·cm^-1 lower, respectively, than that of CK; Moreover, total nitrogen, total phosphorus, total potassium, and organic matter content of T2 increased by 44.8%, 9.1%, 6.5%, and 115.2%, respectively. The content of saline-alkali ions in the soil was reduced by returning rape green manure to the field. Compared with CK, the content of T2 salt composition Ca²⁺, K⁺, Mg²⁺, Na⁺, Cl^-, SO₄^2-, CO₃^2-, and HCO₃^- significantly(P<0.05)decreased by 30.3%, 42.7%, 41.0%, 30.5%, 39.2%, 33.0%, 32.2%, and 32.1%, respectively. The results indicated that rape green manure could improve the physical and chemical properties of soil, increase nutrient content, decrease salinealkali ion content, and have a good effect on saline-alkali soil improvement in the oasis arid area of Xinjiang.