| 引用本文: | 陈文娟,李明思,李清林,等.覆膜滴灌条件下的土壤盐分表聚特征研究 [J].灌溉排水学报,0,():-. |
| CHEN Wenjuan,LI Mingsi,LI Qinglin,et al.覆膜滴灌条件下的土壤盐分表聚特征研究 [J].灌溉排水学报,0,():-. |
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| 摘要: |
| 【目的】探究新疆地区覆膜滴灌农田膜外土壤盐分表聚特征。【方法】以沙土和壤土为研究对象，通过室内试验，对2种质地的土壤分别进行了高蒸发强度和低蒸发强度处理，观测了覆膜滴灌条件下土壤盐分的水平分布和垂直分布；不同温度处理下，对2种质地的土壤进行了盐分表聚发展过程试验。【结果】覆膜滴灌条件下，2种土质的表层含盐量随距滴头水平距离呈指数函数分布；膜外土壤垂直剖面上的含盐量呈“Γ”型分布，盐分主要聚集在表层土壤中。其中，高蒸发强度处理下，沙土表层（0～2 cm）的平均含盐量是2 cm以下土层平均含盐量的7.3倍，壤土表层（0～2 cm）的平均含盐量是2 cm以下土层平均含盐量的8.4倍；低蒸发强度处理下，沙土和壤土的对应数值分别是7.2倍和7.9倍。影响土壤盐分表聚的主要因素是土壤水分的蒸发速率；土壤含水率、环境温度和蒸发强度的提高都可以增大土壤水分蒸发速率，导致土壤表面盐分聚集量增加，其中，土壤含水率所起的作用最大。土壤水分对盐分的溶解度随含水率的降低而下降，导致蒸发过程中盐分表聚速率存在峰值，而且峰值基本与环境温度正相关。【结论】土壤水分汽化散失使盐分从溶液中离析是导致土壤盐分表聚的本质；蒸发作用下，壤土的盐分表聚速率比沙土的盐分表聚速率高。 |
| 关键词: 覆膜滴灌;土质;盐分表聚;聚集速率 |
| DOI： |
| 分类号:S |
| 基金项目:国家自然基金重大项目——西北旱区农业节水抑盐机理与灌排协同调控（51790533） |
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| Characteristics of Surface Soil Salt Accumulation Under Mulched Drip Irrigation |
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CHEN Wenjuan1, LI Mingsi2, LI Qinglin2, LI Dongwei2
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1.College of Sciences,Shihezi University;2.College of Water Conservancy and Architectural Engineering,Shihezi University
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| Abstract: |
| 【Background】Under mulched drip irrigation, soil salt was suppressed below the root layer and pushed out to the space outside the membrane. Under the action of surface evaporation, the salt accumulation characteristics of the soil outside the film appear. Mastering the characteristics of soil salt accumulation under mulched drip irrigation is not only an important basis for developing soil salinization control technology in Xinjiang, but also the primary problem to be solved in the improvement and utilization of saline alkali land.【Objective】Exploring the salt accumulation characteristics of soil outside film in farmland under mulched drip irrigation in Xinjiang. 【Method】 In this study, sandy soil and loam soil were treated with high evaporation intensity and low evaporation intensity at the same time by indoor physical experiments. The horizontal and vertical distribution of soil salinity under mulched drip irrigation was observed, and each group of treatments was repeated three times. Under different temperatures treatments, the salt surface aggregation development process of two kinds of soils were tested at the same time, and each treatment was repeated six times.【Result】 Under the condition of mulched drip irrigation, the distribution of salt content in the surface layer of the two soils was exponential function with the horizontal distance from the emitter. The salt content in the vertical profile of the soil outside the film showed an obvious "Γ" type distribution, and the salt mainly concentrated in the surface soil. The average salt content in the surface layer (0-2cm) of sandy soil was 7.3 times that in the soil layer below 2cm, and the average salt content in the surface layer (0-2cm) of loam soil was 8.4 times that in the soil layer below 2cm.The evaporation rate of soil water is the main factor affecting the surface accumulation of soil salt. The increase of soil moisture content, environmental temperature and evaporation intensity can increase the evaporation rate of soil moisture, and lead to the increase of surface soil salt accumulation, among which the soil moisture content plays the most important role. Because the solubility of soil water to salt decreases with water content, there is a peak value of salt accumulation rate during the evaporation process, and the peak value is basically positively correlated with the environmental temperature.【Conclusion】The vaporization and loss of soil water caused the separation of salt from the solution, which was the essence of soil salt surface accumulation. The salt accumulation rate of loam soil is basically higher than that of sandy soil. The research results can provide help for understanding the soil water and salt movement in field with mulched drip irrigation. |
| Key words: mulched drip irrigation; soil texture; salt Accumulation; accumulate rate |
