摘要
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、35 cm,以地表滴灌（DI）为对照,共4个处理,经过2~4 a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1 m的90°扇形区域内0~100 cm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显著增加了根径小于5 mm根系根长密度,细根（根径小于2 mm）是DI的3倍,但减少了根径大于5 mm根系根长密度,相对增加了20~40 cm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与树干水平距离的增加而减小的趋势,但在0~20 cm土层减小的幅度较大,在20~40 cm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27~35 cm。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。
To investigate the effects of installation depths of water-conduct device on root distribution and root growth in dwarf close planting jujube under indirect subsurface drip irrigation（ ISDI）, three installation depths of water-conduct device were considered in the experiment. The installation depths of water-conduct device were 20 cm（ T1）,27 cm（ T2） and 35 cm（ T3）,respectively,with surface drip irrigation（ DI） as comparison. Different depths,horizontal distances of jujube roots system distribution were obtained by annular ditch layered methods,the results showed that there were significant differences in jujube roots system distribution under DI and ISDI. On root morphology,root distributions were shallow and horizontal extension under DI. The distribution of root in different soil layers was uniform,and growth direction of root was basically downward under ISDI. ISDI significantly increased the root length density of fine roots（ d 5 mm）,which increased by 1 ~ 2 times than that of DI. Root length density of d〉 5 mm and root system distribution distance in horizontal direction were reduced,and the proportion of fine root length in 20 ~ 40 cm soil layer was increased. With the increase of depth of waterconduct device,the root length density of fine roots（ d 〈2 mm） was decreased in 0 ~ 20 cm soil layerand increased gradually in 20 ~ 60 cm in vertical direction under ISDI. In horizontal direction,the fine root length density of each treatment was comparatively concentrated distribution in 0 ~ 20 cm soil layer,70% of root was distributed in horizontal range of 0 ~ 20 cm,the fine root distribution distance of each treatment was increased. With the increase of depth of water-conduct device,the horizontal distribution distances of roots of different diameter in 0 ~ 20 cm soil layer tended to be reduced,but that in 20 ~40 cm soil layer tended to be increased. Generally,with the increase of depth of water-conduct device,fine root distribution showed developing trend from shallow and wide to narrow and deep.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2016年第8期81-90,共10页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(51069013
51369028)
国家级大学生创新创业训练计划项目(201410757004)
关键词
枣树
间接地下滴灌
灌溉深度
根系
水分利用率
jujube tree
indirect subsurface drip irrigation
irrigation depth
root
water use efficiency
