地膜与秸秆双重覆盖对渭北苹果园土壤水分及产量的影响

针对渭北果园土壤干燥化、覆盖条件下夏季土壤高温抑制根系生长的问题，通过将具有高效保水效果的地膜与缓温效应显著的秸秆两种覆盖材料组合，从保墒、调温及对果树产量影响方面综合评价双重覆盖(地膜压长麦秆覆盖、长麦秆压地膜覆盖、地膜压短麦秆覆盖、地膜压玉米秆覆盖)模式。结果表明，地膜压短麦秆覆盖相对于其它处理能提高0~600 cm土壤剖面年平均贮水量(1 529.2 mm)及年平均含水量(25.71%)，有利于果树对水分的利用；地膜压短麦秆覆盖在春季和秋季能提高土壤温度，夏季降低土壤温度，具有良好的缓温效应；不同覆盖 处理均能提高果树的产量、单果重和优果率，其中地膜压短麦秆覆盖单株产量(48 kg)和优果率(85%)最高，为最佳覆盖模式。

Effects of dual mulching of film and straw on soil moisture and apple yield in Weibei Region

To alleviate the problems of soil desiccation and the growth inhibition of apple roots by high soil tempera-ture under summer mulching condition in apple orchards of Weibei region, film mulching was combined with straw mulching to preserve soil water and buffer high temperature. A comprehensive evaluation was conduced to evaluate four different dual mulching modes such as film over long wheat straw, long wheat straw over film, film over short wheat straw, and film over maize straw, with respect to the aspects of moisture conservation, temperature adjusting and mulching effects on apple yield. Results show mulching treatment of film over short wheat straw, compared with other treatments, inereased annually averaged water storage by 1 529.2 mm and annually averaged water content by 25.71% in the 0~600 cm soil profile, which is beneficial to water utilization by fruit trees. The mulching treatment of film over short wheat straw inereased soil temperature in spring and autumn but redueed soil temperature in summer, indicating a better effect ton buffering soil temperature. All these four mulching treatments showed improvement of apple yield, single fruit weight and optimal fruit rate.The mulching treatment of film over short wheat straw, having the highest single fruit weight(48 kg)and optimal fruit rate(85%), was the best dual mulching mode.