Abstract:

【Objective】 To investigate the effect of insertion subsurface drip irrigation on infiltration and water-salt distribution of saline soils, 【Methods】 To compare and analyze the effect of different drip head flow rates and drip head burial depths on soil wetting peak transport and water and salt distribution inside the wetted body through indoor soil column tests with saline soils that return to salt in spring in the Alar irrigation area. 【Results】 The results showed that under the same infiltration time and drip head flow rate conditions, subsurface drip irrigation increased the wetting peak depth, wetted area, average soil water content and desalination depth inside the wetted body than surface drip irrigation.Compared with CK treatment, soil wetting peak depth and soil wetting area increased by 20.89% and 18.01% in T₁ treatment, respectively; soil wetting peak depth and soil wetting area increased by 45.78% and 19.06% in T₂ treatment, respectively.mean soil water content within the wetted body increased by 2.48% and 1.37% in T₁ and T₂ treatments, respectively.The soil desalination depth increased from 10 cm to 25 cm.increasing the drip head burial depth and flow rate was able to increase the soil water holding efficiency, which was 2.56%, 3.82%, 9.81% and 13.35% for the 0-25 cm soil layer in treatments T₁-T₄, respectively.The drip head flow rate was small, and the soil salt accumulation rate was 67.98% with the increase of drip head burial depth.the soil salt accumulation rate of 0-5 cm soil layer depth in T₂ treatment was 67.98%.If the drip head flow rate was increased, the soil desalination depth and desalination rate increased with the increase of drip head burial depth, and the maximum soil desalination rate reached 79.15% at 0-30 cm soil depth in T₄ treatment. 【Conclusion】 With the goal of increasing soil wetting area, soil desalination area and desalination rate, the drip head flow rate of 0.6 L/h and burial depth of 15 cm were optimal for the treatment.

Key words: insertion subsurface drip irrigation; soil moisture; soil water holding efficiency; soil salinity; soil desalination rate

摘要：

【目的】 研究插入式地下滴灌对盐碱土壤入渗与水盐分布的影响。【方法】 采用室内土柱试验,以阿拉尔灌区春季返盐的盐碱土土壤为研究对象,比较分析不同滴头流量与滴头埋深,对土壤湿润峰运移和湿润体内部水分及盐分的影响规律。【结果】 相同入渗时间和滴头流量条件下,地下滴灌比地表滴灌湿润峰深度、湿润面积、湿润体内土壤平均含水量和脱盐深度增加。与CK处理相比较,T₁处理土壤湿润峰深度和土壤湿润面积分别增加20.89%和18.01%;T₂处理土壤湿润峰深度和土壤湿润面积分别增加45.78%和19.06%。T₁和T₂处理土壤湿润体内含水量平均值分别增加2.48%和1.37%。土壤脱盐深度由10 cm增加至25 cm。增加滴头埋深和流量,能够增加土壤持水效率,T₁~T₄处理0~25 cm土层土壤持水效率分别为2.56%、3.82%、9.81%和13.35%。滴头流量较小,随滴头埋深增加,土壤盐分表聚。T₂处理0~5 cm土层深度土壤积盐率为67.98%。若增加滴头流量,随滴头埋深增加土壤脱盐深度和脱盐率增加,T₄处理0~30 cm土层深度土壤脱盐率最大达79.15%。【结论】 以增大土壤湿润面积、土壤脱盐区和脱盐率为目标,滴头流量0.6 L/h,埋深15 cm处理最优。

关键词: 地下滴灌, 土壤水分, 土壤持水效率, 土壤盐分, 土壤脱盐率