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为探讨间接地下滴灌及导水装置埋深(灌溉深度)对南疆极端干旱区矮化密植红枣根系生长分布特征及产量、水分利用率的影响,试验设间接地下滴灌(ISDI)3个导水装置埋深水平:分别为20、27、35cm,以地表滴灌(DI)为对照,共4个处理,经过2~4年的田间试验后,采用环状壕沟分层挖掘法对以枣树树干为中心,半径为1m的90°扇形区域内0~100cm土层进行根系取样。结果表明,相对于DI,ISDI下各根系分布较均匀,生长方向基本向下延伸;ISDI显著增加了d<5mm根系根长密度,细根(d<2mm)是DI的3倍,但减少了d>5mm根系根长密度,相对增加了20~40cm土层根系根长占总根长的比率;垂直方向上随着灌溉深度的增加表层根系根长密度相对减少,深层相对增加;水平方向上各处理根系根长密度基本呈现随着距树干水平距离的增加而减小的趋势,但在0~20cm土层减小的幅度较大,在20~40cm土层其减小的幅度较小;随着灌溉技术由DI到ISDI及灌溉深度的增加,细根分布基本呈现出由“宽浅型”向“深根型”发展的趋势。相对DI,ISDI具有较好的节水增产效果,提高产量及灌溉水生产率最大达20%。建议幼龄期南疆密植枣树的导水装置埋深为27~35cm左右。研究为极端干旱区枣树适宜灌溉技术的选择及其技术要素的制定提供依据。
In order to investigate the effects of indirect subsurface drip irrigation and depth of water-conducting device (irrigation depth) on the growth distribution, yield and water use efficiency of dwarf-dense red dates in the southern arid region, The depth of the device: 20,27,35cm, respectively, with surface drip irrigation (DI) as a control, a total of four treatments, after 2 to 4 years of field trials, the use of annular trench dredging method to jujube tree trunks As the center, a radius of 1m 90 ° sector 0 ~ 100cm soil layer root sampling. The results showed that the roots of ISDI distributed more evenly and the growth direction extended downwards than that of DI. ISDI significantly increased the root length density of d <5mm, while the number of fine roots (d <2mm) was three times that of DI but decreased d> 5 mm root root length relative density increased relative root root length of 20 ~ 40 cm soil layer total root length ratio; vertical direction with the increase of irrigation depth surface root root length relative density decreased relatively deep; horizontal direction The root length density of all treatments tended to decrease with the increase of the horizontal distance from the trunk, but decreased more in 0-20 cm soil layer and smaller in 20-40 cm soil layer. With the increase of irrigation technology from DI to ISDI and irrigation depth, the distribution of fine roots basically showed a trend from “shallow” to “deep root”. Relative to DI, ISDI has better water-saving and yield-increasing effects, increasing yield and irrigation water productivity up to 20%. It is suggested that the depth of water-conducting device of jujube tree planting in southern Xinjiang is about 27 ~ 35cm. The study provided the basis for the selection of suitable irrigation techniques and the formulation of its technical factors for Jujube in extreme arid region.