咸水膜下滴灌频率对土壤表层水盐环境的影响

发布时间：2018-07-12 18:29

本文选题：民勤绿洲 + 咸水　；参考：《灌溉排水学报》2017年08期

【摘要】：为了更好地指导干旱区农业生产,利用地下咸水进行了膜下滴灌频率试验,设3种滴灌频率,即1次/24 h(T1)、1次/48 h(T2)和1次/72 h(T3),探讨了相同灌水量下不同滴灌频率对土壤表层水盐环境的影响。结果表明,(1)T2处理浅层土壤含水率高于T1和T3处理0.5%~1.0%,且试验后期形成面积和深度均大于T1和T3处理的;(2)土壤电导率在整个试验过程中呈增加趋势,T2处理土壤电导率增长幅度相对较小,土壤返盐程度较小;(3)土壤p H值在试验中期增大,试验后期减小,表层土壤p H值达8.5左右;(4)土壤表层各盐分离子量在试验期间的增加程度远小于土壤结冻期;土壤表层重碳酸根离子量在试验后期超过120.0 mg/kg,土壤总碱度增大,土壤存在碱化趋势。因此,滴灌频率1次/48 h可为作物提供比较适宜的土壤表层水盐环境,可作为民勤绿洲咸水滴灌频率参考值;同时,使用咸水滴灌后,绿洲土壤存在明显碱化趋势,因此还需采取其他灌排措施减弱土壤次生盐渍化。
[Abstract]:In order to better guide agricultural production in arid area, the frequency experiment of drip irrigation under film was carried out with underground salt water, and three kinds of drip irrigation frequency were set up. The effects of different drip irrigation frequency on the soil surface water and salt environment under the same irrigation amount were studied. The results were as follows: 1 / 24 h (T1) 1 / 48 h (T2) and 1 / 72 h (T3). The results showed that: (1) the moisture content of shallow soil in T2 treatment was higher than that in T1 and T3 treatments, and the formation area and depth of T2 treatment were higher than those of T1 and T3 treatments in the later stage of the experiment, and (2) the soil conductivity of T2 treatment showed an increasing trend during the whole experiment. The increase is relatively small, (3) the pH value of soil increased in the middle period of the experiment, decreased in the later stage of the experiment, and reached about 8.5 in the surface soil, (4) the amount of salt ions in the surface layer increased much less than that in the freezing period of the soil. The amount of heavy carbonate ions in the topsoil was more than 120.0 mg / kg in the later stage of the experiment, and the total alkalinity of the soil increased and the soil was alkalized. Therefore, the frequency of drip irrigation per 48 h can provide suitable soil surface water and salt environment for crops, and can be used as the reference value of salt water drip irrigation frequency in Minqin oasis, at the same time, after using saltwater drip irrigation, the oasis soil has an obvious trend of alkalization. Therefore, other irrigation and drainage measures should be taken to reduce soil secondary salinization.
【作者单位】：中国科学院西北生态环境资源研究院中国科学院沙漠与沙漠化重点实验室;中国科学院大学;甘肃源岗农林开发有限公司;
【基金】：中国科学院院地合作项目(Y62B631001) 国家自然科学基金青年科学基金项目(41301615)
【分类号】：S156.4

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