不同耕作方式土壤水分动态变化

Dynamic Changes of Soil Water Content under Different Tillage Methods

本研究在长期定位试验（1983年开始）条件下,研究了宽窄行、免耕、翻耕和常规耕作4种耕作方式土壤水分时空变化规律。结果表明：不同年份0~60 cm土壤含水率季节性变化趋势不规律。从平均土壤含水率来看,宽窄行（苗带）〉宽窄行（茬带）〉免耕〉翻耕〉常规耕作,2010~2012年宽窄行（苗带）较常规耕作高1.3个百分点。宽窄行（苗带）或（茬带）播种前0~20 cm土壤含水率明显高于其他处理,其次为免耕,土壤含水率最低为翻耕,差异达到显著（p〈0.05）或者极显著（p〈0.01）水平。从播种前至成熟期,不同耕作方式0~60 cm土壤含水率基本呈上升趋势,30~50 cm土壤含水率较高,宽窄行（苗带）50~60 cm土壤含水率深松后最高,深松后不仅有利于接纳雨水,而且土壤水分有由茬带向苗带侧下方运移的趋势。

In this study, dynamic changes of soil water content was studied with wide/narrow row alter- nation planting, no-tillage, plow tillage and conventional tillage under long-term experiment begun in1983. The results showed that seasonal change of 0 - 60 cm soil water content with was irregular in different years. From a viewpoint of average soil water content, W/NRAP （seeding band） 〉 W/NRAP （stubble band） 〉 NT 〉 PT 〉 CT, which was 1.3 percentage higher in W/NRAP （seeding band） than CT from 2010 to 2012 years. Soil wa- ter content in 0 - 20 cm of W/NRAP （seeding band） or W/NRAP （stubble band） was significantly higher than other treatments, followed by the NT, PT was minimum, and the difference was significantly （p 〈0.05） or highly significant （p 〈0.01） levels before sowing. From sowing to harvest, soil water content at 0 - 60 cm appeared rising trend. Soil water content at 30 - 50 cm was higher than other layer. It was the highest after deep loosen for W/NRAP （seedling band） 50 - 60 cm, because of deep loosen not only stored rainfall, but also transported water from stubble band to the bottom of seeding band.