In order to identify soil water temporal and spatial distribution and water-saving efficiency under straight tube root irrigation,root irrigation experiment in the Jujube ecological and economic forest of downstream part of Tarim river was carried out.The results showed that:(1) In straight root irrigation process,the distribution of soil moisture was at soil layer from 0 to 100 cm;with the increase in irrigation time,the soil water content of soil layer from 0 to 20 cm was fluctuating,that of soil layer(80 ～ 100 cm) stable,and that of the rest soil was on the rise of S type;(2) The maximum value of average soil water content of one-meter deep soil layer and the time at which the value was reached were 44.62％ and 7.5 h,in jujube growth stage,43.26％ and 12.5 h in flowering stage,46.3％ and 15 h in young fruit period;(3) In the process of root irrigation,the variation coefficient of soil water content at each soil layer was ranked in the descending order,80 cm ＞ 20 cm ＞ 40 cm ＞ 60 cm ＞ 100 cm.After irrigation,there was significant difference in the average soil water content at 80 cm,100 cm layer and that at rest layers.There was no significant difference in the average soil water content between the soil layer of 20 cm,40 cm and 60 cm.The spatial heterogeneity of soil water content in 80 cm soil layer was the highest;(4) 20 days after the three experiments,the regression rate of the average soil water content in 0 ～ 100 cm soil layer was 0.21％· d-1,0.19％· d-1 and 0.17％· d-1 respectively.With regard to soil volumetric water content,the regression rate of the 60 cm and 100 cm soil layer remained stable,that of 40 cm soil layer faded before it increased,that of 20 cm soil layer faded rapidly in the first ten days,and that of 80 cm soil layer faded rapidly in the latter ten days.(5) The water-saving efficiency of straight tube root irrigation was 27.78％ higher than surface drip irrigation.The water use efficiency of straight tube root irrigation was 8.12％ and 52.46％ higher than respectively than surface drip irrigation and flood irrigation.%在塔里木河下游枣树生态经济林进行根灌试验,研究了直插式根灌条件下的土壤水分时空分布和节水效率.结果表明:(1)灌水过程中直插式根灌的土壤水分分布在0～ 100 cm土壤层,随灌溉时间增加,土壤含水量,0～20 cm土层呈波动变化,80～100 cm土层基本稳定,其余各土层呈S型增加;(2)不同时期1 m深土层平均土壤体积含水量最大值及达到最大值的时间,枣树生长初期为44.62％、7.5h,花期为43.26％、12.5 h,幼果期为46.3％、15 h;(3)根灌过程中,各土层土壤含水量变异系数大小次序为80 cm＞20 cm＞40 cm＞60 cm＞ 100 cm;灌后土壤平均含水量,80、100 cm土层与其余各层之间差异显著,20、40、60 cm土层之间差异不显著,80cm土层土壤含水量空间异质性最高;(4)三次试验后20d内,0～100 cm土层的平均土壤体积含水量消退速率分别为0.21％·d-1、0.19％·d-1和0.17％·d-1,土壤体积含水量60 cm和100 cm土层消退速率稳定,40 cm土层呈先消退后增加的趋势,20 cm土层0～10d迅速消退,80 cm土层11～20d迅速消退;(5)直插式根灌的节水效率比地表滴灌高27.78％,水分利用效率分别比地表滴灌和漫灌高8.12％、52.46％.
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