秸秆覆盖旱作瓜田土壤水分的空间变化及对西瓜产量的影响

为了探明秸秆覆盖栽培对西瓜产量及土壤水分的影响，选用玉米秸秆在生育期设置地表全覆盖（WM）、行间覆盖（SM）和根域覆盖（RM）3个覆盖处理，以不覆盖为对照（CK），研究不同秸秆覆盖方式对旱作西瓜不同生育时期土壤总贮水量、不同深度土壤含水量及产量的影响.结果表明：秸秆地表全覆盖和根域覆盖处理显著提高了西瓜全生育期根域和行间0～120 cm的土壤含水量和贮水量，且伸蔓后期以后的土壤贮水量根域高于行间；秸秆覆盖处理对西瓜伸蔓后期至膨大前期的土壤含水量影响最大，随着西瓜的生长发育，秸秆覆盖处理提高根域土壤含水量的幅度增加，深度下延.秸秆覆盖处理提高西瓜产量主要受根域土壤水分条件改善的影响；各覆盖处理均显著提高了西瓜的产量和水分利用效率，WM、SM和RM处理的增产幅度分别为24.8%、11.5%和15.1%，水分利用效率分别提高了42.7%、24.3%和294%.以地表全覆盖13500 kg·hm^-2秸秆量的处理蓄水保墒、提高西瓜产量和水分利用效率的效果最显著.

Effects of straw mulching on soil moisture and watermelon yield in dryland.

To explore the effects of straw mulching on soil moisture and yield of watermelon, corn straw was used as mulching materials, and three straw mulch treatments were performed, i.e., whole mulch (WM), rows mulch (SM) and root domain mulch (RM), and non mulching as control. The results indicated that WM and RM treatments increased significantly soil water storage in 0-120 cm of soil layer under root domain and rows compared with the control during watermelon growth period, and soil water storage of RM was higher than that of SM after growing tendril. Effects of all straw mulch treatments on soil moisture were most obvious from watermelon post growing tendril to pre swelling and maturity. With the growth and development of watermelon, the three straw mulch treatments improved soil moisture around root domain, resulting in increased watermelon yields. Compared with the CK, the WM, SM and RM treatments significantly improved the yield and the water use efficiency of watermelon by 24.8%, 11.5% and 15.1%, and 42.7%, 24.3% and 29.4%. The WM with 13500 kg·hm^-2 straw was recommended for watermelon production in arid areas due to its favorable effect on soil storage moisture, yield and water use efficiency.