保护性耕作下黑土水热动态研究

通过连续监测东北典型黑土耕作长期定位试验下的土壤含水量和温度,研究了保护性耕作措施下农田黑土水热动态规律。结果表明:免耕秸秆覆盖(NTS)可显著提高0~50 cm土层水分含量,其中免耕在0~20 cm土层平均土壤体积含水量最高值分别比少耕(RT)和传统(CT)高3%~10%,尤其是可提高作物播种期表层土壤含水量。0~10 cm土层深度范围内RT土壤温度均高于NTS和CT,其中5 cm土层土壤温度日平均最高值较NTS和CT分别高3.04℃和5.27℃。三种耕作措施下的水热动态表明,少耕是我国东北旱作黑土区最佳的保护性耕作措施。

Dynamics of soil water and temperature under conservational soil tillage

Based on a long term field experiment in the northeast arable black soil, the soil water and temperature was monitored continuously, the dynamics of soil water and temperature under conservational soil tillage was studied. The results showed that no-tillage with mulch (NTS) could increase soil water content in 0 ~ 50 cm, the highest average volu-metric soil water content in 0 ~ 20 cm layer was three and ten percent points higher than that of reduced tllage(RT) and conventional tllage(CT), respectively, especially during the stage of sowing. The average daily soil temperature in 0~10 cm layer of RT was higher than that of NTS and CT . The highest average daily soil temperature of RT at 5 cm depth was 3.04C and 5.279 higher than that of NTS and CT, respectively. The results of soil and water dynamics under three different tillage systems indicated RT was the optimum soil tillage operation in the arid black soil area of China.