土壤保护耕作对怀来县玉米地沙化的阻滞效果

采用大区对比方法,研究了土壤保护耕作措施对怀来县玉米地沙化的阻滞效果。结果表明,玉米整秆留茬越冬,地表风速降低24%~71%,春播前保墒相当于增雨7·6mm;高度15~30cm的普通留茬玉米地,地表风速减小9%~16%,而耙擦灭茬的地块风阻仅2%。玉米整秆留茬越冬,地表土<0·1mm的土壤颗粒由585·9g/kg提高到691·3g/kg,降尘效果明显;普通留茬处理的地表土>0·1mm的颗粒比例增加了31%。玉米苗期土壤的保墒蓄水效果以整秆留茬粉碎还田覆盖结合深松方法最好;深松处理增产幅度最大。

A Preliminary Study in Tillable Field Desertification Prevention Techniques in Huailai

Ground wind speeds have been reduced by 24%~71%,9%~16% an d 2% by whole corn stalk mulching,15~30 cm stubble mulching,and no mulching with stubble erased respectively.More soil water,equivalent to a rainfall of 7.6 m m,has been conserved at spring sowing season by whole corn stalk mulching. The whole stock mulching treatment was effective at reducing soil desertificat ion,with soil granules of <0.1mm diameters remained after winter within top soil having increased to 69 1.3 g/kg,as compared with 585.9g/kg for the control.While soil granules of >0 .1mm diameters of 15~30 cm stalk mulching treatment increased by 31%.As for th e soil water conservation effect,the results were whole stock winter mulching wi th cut stalk spring mulching and subsoiling > only subsoiling > no tillage > til lage.Subsoiling performed best at increasing grain yield.