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题名	塔里木沙漠公路防护林土壤水盐动态研究
作者	王永东
学位类别	博士
答辩日期	2009
授予单位	中国科学院．新疆生态与地理研究所
导师	徐新文，新疆生态与地理研究所
关键词	塔里木沙漠公路防护林
其他题名	Research on the dynimics change of soil moisture and salt of shelterbelts at Tarim Desert Highway
中文摘要	塔里木沙漠公路防护林生态工程的建立创造了人类治沙防沙的历史。然而，要维持塔里木沙漠公路防护林的正常生长，在极端干旱区高矿化度咸水滴灌灌溉条件下的防护林地面临着基本的水少与盐多的困惑。本论文选择塔里木沙漠公路防护林地为研究对象，对处于极端干旱条件下防护林地的水盐运动进行系统研究，目的是为了面向塔里木沙漠公路防护林地可持续发展提供科学依据。主要研究内容和结论如下： 1） 风沙土土壤水分入渗速率与入渗时间的关系符合Horton公式，其土壤水分稳定入渗率为4754.16mm/d。风沙土水分在入渗过程中，湿润锋推移过程用乘幂关系拟合较好；在再分布过程中，幂函数与对数关系拟合较好。 2） 塔里木沙漠公路防护林地的土壤水分时间动态属于灌溉周期型；随灌溉年限的增加，防护林地土壤水分与土壤贮水量都呈递减趋势，而土壤水分亏缺量越来越大；土壤水分垂直变化上可以将其划分为土壤水分速变层、中变层、弱变层以及土壤水分稳定层4个层次；从不同立地类型土壤水分动态分析，板结沙地的土壤贮水量远远高于沙垄、粘土地与平沙地。 3） 土壤盐分表聚性强、表层含盐量最高而向下层迅速减少，而且随着灌溉的持续进行，盐分表聚进一步加剧是塔里木沙漠公路防护林地土壤盐分最基本特征；防护林地土壤盐分组成是以钠型氯化物为主，土壤电导率、土壤盐分含量等都属于中等变异性，土壤pH表现为弱变异；土壤盐分在剖面上的分布类型主要表现为表聚型。 4） 风沙土畦灌与滴灌条件下土壤盐分累积除在表层与200cm以下土层出现差异，其它层次无明显差异，滴灌的表层积盐量大于畦灌；土壤积盐程度随灌溉水矿化度的增加而加重。灌溉年限和立地类型对土壤盐分的积累存在着明显差异，沙垄区2006年和2008年土壤剖面平均电导率分别是2005年的1.08倍和1.12倍；板结沙地分别是2005年的1.34倍与1.81倍；粘土地达到2005年的2.12倍和2.74倍，土壤盐分累积趋势显著。 5） 滴灌区，土壤表层盐分在不同林地出现差异，在各个区位土壤表层盐分空间变异不稳定，呈现不同理论模型。Krigng空间插值分析表明，滴灌区与漫灌区土壤表层盐分含量的空间分布均呈现出条带状和斑块状格局，表层土壤电导率的破碎化比较严重。 6） 沙拐枣林地蒸散量大于柽柳林地，2006~2008三年平均，从4月到10月沙拐枣防护林的平均蒸散量为1029mm，而柽柳防护林地的蒸散量为918mm；柽柳林地与沙拐枣林地年平均蒸散量占到同期灌溉量的90%以上；土壤贮水量在一定程度上起着重要的调蓄作用。 7） 塔克拉玛干沙漠强烈的蒸发作用，在土壤表层0~20cm上出现积盐现象；而20~200cm植被主要根系层土壤盐分没有发生累积；在防护林地不同立地类型区，土壤脱盐率与土体构型存在很大关系。夹粘平沙地区区土壤脱盐迅速，盐分积累在土体粘土层部位；平沙地表现为少许脱盐，植被根系层脱盐率为2.7%，而板结沙地区则表现为土壤盐分持平状态。The construction of the Trim Desert Highway shelterbelt eco-project created the history of control and prevention of desertification. But in extreme arid area and with high salinity water drip-irrigation, it is hard to maintain the normal growth of shelterbelt because less water and more salt are main issues. Soil in the Trim Desert Highway shelterbelt was selected as the study object in this paper, soil moisture and salt movement was systematic studied, which should provide scientific basis for sustainable development of the Trim Desert Highway shelterbelt. Main results concluded are as follow: （1）Relationship between infiltration rate and infiltration time of aeolian sandy soil water was accorded with Horton Formula, and its stable infiltration rate was 4754.16mm/d. In the infiltration process of aeolian sandy soil water, it was better to fit the moving process of wetting front with power relation, and in redistribution process, power function and logarithmic relationship fitted better. （2）Soil moisture dynamics change of the Trim Desert Highway shelterbelt belonged to irrigation cycle type. With increase of irrigation period, soil water content and moisture storage decreased gradually, and quantity of water deficit became larger. Vertical change of soil moisture could be divided into 4 layers, soil moisture quick changing layer, mid-changing layer, weak changing layer and stable layer. Moisture storage of hardening sandy land was far larger than longitudinal dune, clay land and flat sandy land. （3）Salt accumulated strongly at surface soil, salt content of surface layer was highest and decreased fast from surface layer to lower layers, salt accumulated further intensified with irrigation continuancewhich was most basic characteristics of soil salt in the Trim Desert Highway shelterbelt. Soil salt composition of shelterbelt was mainly Na-Cl, soil conductivity and salt content belonged to mid-variability, and soil ph manifested as weak variability. The type of soil salt distribution on profile mainly manifested as surface accumulation type. （4）Under furrow irrigation and drip-irrigation, Aeolian sandy soil salt accumulated different at surface layer and layer under 200 cm, and had no obvious difference at others layers, and surface of salt accumulation quantity under drip-irrigation was larger than furrow irrigation. Soil salt accumulation level aggravated with mineralization of irrigation water. There was obvious difference of soil salt accumulation at different irrigation periods and site types. （5）At drip-irrigation area, surface soil salt had difference at different forests, and space variation was unstable at different position, manifested different theoretical models. Krigng space interpolation analysis showed that surface soil salt content at drip-irrigation area and furrow irrigation area manifested banding and plaque distribution pattern, and landscape fragmentation of surface soil conductivity was serious. （6）Evapotranspiration of Calligonum forest was lager than Tamarix forest. from April to October, average evapotranspiration of Calligonum forest was 1 029 mm, and Tamarix forest was 918 mm. Evapotranspiration of Calligonum forest and Tamarix forest account for more than 90% of simultaneous irrigation quantity. Soil water storage had important effect of regulation and storage at different degrees. （7）Strong evaporation in the Taklimakan Desert caused salt accumulation at surface soil of 0-20 cm, but salt accumulation didn’t happen at main distribution layer of plants roots at 20-200 cm layer. Soil desalination rate and soil body configuration had great relation at different site types in the shelterbelt. Soil desalted fast in flat sandy land with clay, and salt accumulated at clay layer. Flat sandy land manifested as a little desalinization, Soil desalination rate of plants roots layer was 2.7%, and soil salt of hardening sand land kept same level.
语种	中文
学科主题	水土保持与荒漠化防治
公开日期	2010-11-12
页码	共119页
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/8510]
专题	新疆生态与地理研究所_中国科学院新疆生态与地理研究所(2010年以前数据)
推荐引用方式 GB/T 7714	王永东. 塔里木沙漠公路防护林土壤水盐动态研究[D]. 中国科学院．新疆生态与地理研究所. 2009.

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