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选择黄土高原陇中丘陵半干旱典型区———定西地区,在前期试验研究的基础上,2002～2004年通过对保护性耕作条件下旱地春小麦—豌豆双序列轮作农田土壤水分及利用效率的试验研究,结果表明:保护性耕作能够显著提高0～200cm土层土壤贮水量及含水量,这种作用在降水较少年份表现更为突出。免耕及免耕覆草较常规耕作土壤贮水量分别提高1 93%～7 25%和0 06%～3 58%。休闲轮作有利于提高土壤对降水的保蓄,具有良好的蓄水保墒作用,但不同的轮作序列表现不同。P/W各处理小麦收获期土壤0～50cm含水量均比W/P各处理小麦收获期土壤0～50cm含水量有所增加,增幅为0 33%～0 62%。0～200cm土壤含水量呈反S型变化,播种期、五叶期及收获期土壤具有较高含水量,而开花期土壤含水量则较低。免耕覆草处理的产量及水分利用效率分别为3709 69kg/hm2和10 45kg/hm2·mm,分别较常规耕作提高30 28%和40 08%。
Based on the previous experimental studies, we selected the semi-arid semi-arid typical area in the Longzhong hilly area of the Loess Plateau --- Dingxi. Based on the experiments of 2002-2004, the soil moisture and utilization efficiency of the dry land spring wheat-pea rotation cropland under the protective tillage The results showed that conservation tillage could significantly increase the soil water storage and water content in 0 ~ 200cm soil layer, and this effect was more prominent in the years with less precipitation. Compared with conventional tillage, soil water storage of no-tillage and no-tillage mulching increased by 193% ~ 725% and 0 06% ~ 358% respectively. Leisure rotation is conducive to improve soil conservation of precipitation, with good water storage soil moisture, but different performance of different rotation sequence. The water content of 0-50 cm soil in P / W wheat treatments was higher than the 0-50 cm soil moisture content of W / P treatments in the harvesting period, with an increase of 0 33% -0 62%. Soil moisture at 0 ~ 200cm showed an inverse S-shape, while soil at sowing, five-leaf stage and harvesting stage had higher water content while soil water content at flowering stage was lower. The yield and water use efficiency of no-tillage grass mulching were 3709 69kg / hm2 and 10 45kg / hm2 · mm, respectively, which were increased by 30 28% and 40 08% respectively compared with conventional tillage.