种植绿肥作物对河套灌区盐碱土改良效果研究

Study on the effect of planting green manure crops on the improvement of Saline-Alkali soil in Hetao Irrigation Area

为探求不同绿肥作物对盐碱土的改良效果,以内蒙古河套灌区盐碱土为研究对象,研究田菁、草木樨2种绿肥作物对盐碱土的改良效果。结果表明:连续种植2年绿肥作物均不同程度地降低土壤容重,增加土壤孔隙度和土壤养分含量,其中种植田菁对改善土壤物理性质较为显著,土壤容重下降4.08%、总孔隙度增加5.08%;土壤有机质、全氮、碱解氮、速效磷、速效钾分别较对照(CK)提高49.0%~49.4%,36.8%~68.4%,40.7%~43.8%,36.7%~44.8%,26.2%~36.5%。因此,在河套灌区通过种植田菁、草木樨可改善土壤物理结构,降低盐碱危害,提高土壤养分含量,其中种植田菁对土壤的改良效果优于种植草木樨。

In order to explore the improvement effect of green manure crops on saline soil,this paper takes the saline-alkali soil in Hetao Area of Inner Mongolia as the research subject.Two species of leguminous green manure crops,Sesbania cannabina and Melilotus suaveolens,were used in the field experiments.The results showed that:planting two kinds of green manure crops could reduce the soil bulk density,the soil porosity,and the soil nutrient content.After planting Sesbania cannabina,the soil bulk density decreased by 4.08%and the total porosity increased by 5.08%.The soil organic matter,the total nitrogen,the alkali-hydrolyzable nitrogen,the available phosphorus,and the available potassium increased by 49.0%-49.4%,36.8%-68.4%,40.7%-43.8%,36.7%-44.8%,and 26.2%-36.5%,respectively.Therefore,planting green Sesbania cannabina and Melilotus suaveolens in Hetao irrigation area could noticeably improve the saline soil physical structure,reduce the salt level,and increase the soil organic matter,the total nitrogen,and the available nutrients;the effect of planting Sesbania cannabina on soil improvement was greater than that of planting Melilotus suaveolens.