垄膜集雨对陇东旱塬苹果根系分布及土壤性状的影响

为探明黄土高原旱塬区垄膜集雨措施对苹果根系及土壤性状的影响，以9 a生苹果树为试材，结合田间调查和室内测量的方法，研究垄膜集雨保墒条件下果树根系分布及土壤性质的变化特点。结果表明，垄膜和清耕处理苹果根系水平分布特征相似，垂直分布有明显差异。清耕条件下，富士苹果根系主要分布在距离主干30~150 cm内的20~80 cm深土层中，以40~60 cm土层分布最多；而垄膜集雨处理根系主要集中在 0~20 cm 土层中，占根系总量的48.18%，随着土壤深度的增加，根系生物量减少，表现出根系上浮现象；垄膜和清耕处理土壤体积质量与总根长、根系生物量、根系表面积、根长密度均呈极显著负相关，而土壤含水量与根系各指标呈极显著正相关；垄膜处理下，0~40 cm土壤体积质量明显降低，而土壤含水量显著提高。

Influence of Plastic Film-mulching on Ridge and Rain Harvesting on Root Distribution Characteristics of Apples and Soil Properties in Dryland Orchards of Longdong Areas

The study investigated that the effects of measures of ridge film-mulching and rainfall harvesting on root and soil properties in the loess plateau, nine-yeas-old apple trees were used as the experiment material. Based on field investigation and indoor analysis, the characteristics of horizontal distribution were similar between clean tillage and measures of ridge film-mulching and rainfall harvesting, and the vertical distribution were obviously different. Root of apple trees distributed mainly in the zone to 30-150 cm and in the depth of 20-80 cm soil layer with clean tillage, and reach peak value in the 40-60 cm depth layer. The root system density centralized in the surface layer of 0-20 cm depth layer with ridge film-mulching, where the amount of the fine roots accounted for 48.18% in total. The fine roots biomass declined with the increasing of soil depth, it showed significant phenomenon of root floated to the land surface. Further analysis indicated that the trend of total root length, root biomass, surface area, specific root length and root length density were negative correlation with soil volume mass, and positive correlation with soil moisture. The soil volume mass in the 0-40 cm soil layer decreased significantly and soil moisture greatly improved in ridge film-mulching.