民勤荒漠绿洲过渡带粘土夹层水力性质及其生态水文意义探讨  

Hydraulic properties and eco-hydrology effects of clay interlayer in oasis-desert ecotone of Minqin

作　　者：刘斐耀 尤全刚 薛娴[2,3] 黄翠华 潘晶[2,3] 张丽娟 LIU Feiyao;YOU Quangang;XUE Xian;HUANG Cuihua;PAN Jing;ZHANG Lijuan(College of Geography and Tourism,Hengyang Normal University,Hengyang 421000;Drylands Salinization Research Station,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Minqin 733000;Key Laboratory of Desert and Desertification,Chinese Academy of Sciences,Lanzhou 730000;College of Foreign Languages,Hengyang Normal University,Hengyang 421000,China)

机构地区：[1]衡阳师范学院地理与旅游学院,衡阳421000 [2]中国科学院西北生态环境资源研究院干旱区盐渍化研究站,民勤733300 [3]中国科学院沙漠与沙漠化重点实验室,兰州730000 [4]衡阳师范学院外国语学院,衡阳421000

出　　处：《干旱区资源与环境》2024年第1期114-122,共9页Journal of Arid Land Resources and Environment

基　　金：湖南省教育厅优秀青年项目(22B0716);衡阳师范学院科学基金引进人才启动项目(2022QD12)资助。

摘　　要：土壤水力性质是土壤水文功能的重要组成部分及影响因子,其对土壤水分分布状态、土壤水分循环的强度与速率具有重要影响。粘土夹层虽在干旱区呈不连续分布的状态,但其植被覆盖率却远高于相同水热条件下的非夹粘土壤。文中以民勤荒漠绿洲过渡带粘土夹层为研究对象,对其土壤物理性质、土壤持水性和导水性质进行测量,同时利用壕沟法对该地15年林龄的深根系乡土物种多枝柽柳根系进行了调查,分析了夹粘土壤剖面的水力性质变化特征及其影响因素,探讨了粘土夹层对干旱区植被恢复和重建的生态水文意义。结果表明:1)土壤颗粒组成和有机质含量是影响土壤持水性和导水性的重要因子。2)15年林龄多枝柽柳根系生物量(d<2mm)在粘土夹层上下界面处呈现明显增加的趋势。3)粘土夹层具有较高的持水性,其可通过毛管作用补给其他土层,同时,粘土夹层阻滞了土壤水分的运移,二者的共同作用改善了粘土夹层上下界面处的土壤水分条件。粘土夹层可以改变土壤水分入渗和存储的环境,在含有粘土夹层的土壤上进行植被建设,有助于干旱区固沙植被的恢复和建设。文中研究为了解荒漠绿洲过渡带土壤水文过程、生态恢复和重建提供了一定的数据支持。Hydraulic property is an important part of soil hydrological functions,which influences the soil moisture distribution and the intensity and rate of soil hydrological circulation strongly.Although the clay interlayer is discontinuously distributed in the arid area,the vegetation coverage in this area is often higher than that of non-clayed soils under the same climatic conditions.In this paper,the soil physical properties,soil water holding capacity and hydraulic conductivity of clay interlayer in Minqin desert oasis ecotone were measured.Meanwhile,the root system of Tamarix ramosissima,a deep root native species with 15 years old in this area,was assessed by trenching method.The variation characteristics of hydraulic properties of clay interlayer and its influencing factors were analyzed,and the eco-hydrological significance of clay interlayer for vegetation restoration and reconstruction in arid areas was discussed.The results showed that:1)Soil particle composition and organic matter content are the important factors affecting soil water holding capacity and water conductivity.2)The root biomass(d<2mm)of 15-year-old T.ramosissima increases rapidly close to clay interlayer.3)The clay interlayer has higher water holding capacity,which can rechange other soil layer through capillary action.At the same time,the clay interlayer forms a barrier to prevent soil moisture from migrating to other soil layers,and the combined effect of the two improves the soil water content at the interface of the clay interlayer.Clay interlayer influences the soil environment for water migration and storage,indicating that the clay interlayer is advantageous for the restoration and construction of sand-stabilizing vegetation.This study provides data support for understanding the soil hydrological process,ecological restoration and reconstruction in the desert-oasis ecotone.

关 键 词：粘土质夹层 土壤水力性质 生态水文意义 荒漠绿洲过渡带 

分 类 号：P642[天文地球—工程地质学]