不同覆盖措施对滴灌枣园土壤水热及矿质氮素的影响

Effects of covering methods on soil water,temperature and nitrogen of Jujube Orchard under drip irrigation

为了提高南疆枣园滴灌水肥利用效率,有效改善土壤特性,进行了芦苇秸秆、小麦秸秆、地膜(白色)、玉米秸秆4种覆盖措施的研究。结果表明:4种覆盖措施都能够减少棵间蒸发,提高土壤水分,与对照相比土壤棵间蒸发量分别减少了34.95%、31.08%、35.75%、29.38%,芦苇和地膜的保墒效果较好;保温效果为地膜>小麦秸秆>玉米秸秆>芦苇,芦苇覆盖温度最高土层在10 cm,其他处理均在5 cm处;不同生育阶段各处理土层的矿质氮素含量不同,地膜覆盖能显著影响土壤的硝态氮含量,7—8月中旬覆盖条件下的矿质氮素与对照相比均有所增加,与对照相比7月中旬地膜覆盖提高幅度最大,为323.96%,其含量与气温高低相关;枣树生育阶段前期小麦秸秆覆盖下土壤碱解氮含量相对较高,其中7月中旬增幅最大,达到了57.41%。综合分析表明芦苇覆盖下土壤水热及矿质氮素的田间变异较小。

In order to improve water and fertilizer use efficiency of Jujube Orchard under drip irrigation in South Xinjiang and improve soil properties, we performed a field experiment consisting of four soil coveting patterns including reeds, wheat straw, white plastic film, and corn stalks mulching. The results showed that four coveting methods reduced soil evaporation and improve soil water, compared with the control treatment, by 34.95%, 31.08%, 35.75%, 29.38%, respectively. Reeds and plastic film mulching were the best way for moisture conservation, with the heat insulation effects in the order of plastic mulch 〉 wheat straw 〉 corn stalks 〉 reeds. Reeds coveting had the highest soil temperature in 10 cm depth, while the other treatments in 5 cm. Soil nitrogen content varied with growth stages of Jujube, plastic film mulching significantly affected the nitrate content of soil. Soil coveting obviously increased soil mineral nitrogen content from early July to the mid August. Compared with control, plastic film mulching had an increase of 323.96% in mid July, which is partially due to soil temperature. Alkali-hydrolysable nitrogen was relatively high for wheat straw mulch at the early growth stages, being as high as 57.41 % in mid-July. However, reeds coveting had rela- tively smaller influence on soil water, temperature, and nitrogen.