柴达木地区滴灌水-盐-肥综合调控对枸杞生长和水肥利用的影响

Effects of Water-Fertilizer-Salt Regulation under Drip Fertigation on Lycium Chinensis Growth and the Water and Fertilizer Efficiency in Qaidam Basin

针对柴达木盆地枸杞生产对水-肥-盐综合管理的需求,布置了5个滴灌施肥灌溉比例(施肥量分别为当地枸杞施肥量的10%、30%、50%,70%、90%)的田间试验,试验通过控制滴头正下方20cm处的土壤基质势下限为-20kPa进行滴灌水盐调控和施肥灌溉。结果表明:在柴达木地区,当滴头正下方20cm深度土壤基质势控制在-20kPa以上时,滴灌施肥灌溉阶段土壤盐分会增加,但是土壤仍属于非盐渍土,低耐盐植物可以生长;冬灌盐分淋洗效果显著,冬灌后土壤盐分基本可以维持平衡;随着施肥比例的增加,枸杞的株高、茎粗、冠幅增长率及干鲜果产量先增加再降低,当施肥比例为70%时达到最大;滴灌高频施肥灌溉有利于提高枸杞的产量、灌溉水利用效率和肥料利用率,并且当施肥比例为当地枸杞施肥量的70%左右时,枸杞产量高、灌溉水利用效率高、肥料偏生产力高。

For the water-fertilizer-salt regulation of Lycium chinensis agriculture production under drip irrigation in Qaidam Basin,a field experiment with five drip-fertigation proportions（the amount of drip-fertilization were 10%,30%,50%,70% and 90% of local fertilization）treatments was conducted.The soil matric potential at 20 cm depth under the emitters was controlled above-20 kPa for water-fertilizer-salt regulation.The results showed that the salinity lightly accumulated in soil profile during high-frequent irrigation stage,but the soil was suitable for low salinity tolerant plant because the soil ECe（electrical conductivity of saturated paste extracts）below 4dS/m,but the soil salinity dramatically decreased after the winter drip irrigation;with the increasing of the proportion of fertilization,the increment of Lycium chinensis plant height,stem diameter and crown diameter first increased and then decreased,and got the maximum under 70% of fertilization;the high-frequency fertigation was beneficial to improve the Lycium chinensis yield,water and fertilizer use efficiency,and which got higherst under the 70% of fertilization.