科尔沁沙地东南缘大青沟自然保护区土壤水分的时空分布特征  

Temporal and spatial distribution of soil moisture of Daqinggou Nature Reserve in the southeastern margin of Horqin sandy land,Inner Mongolia,China

作　　者：张楠楠[1] 关文彬[1] 谢静[2] 于明涛[2] 冶民生[2] 苏繁星[2] 

机构地区：[1]北京林业大学自然保护区学院,北京100083 [2]北京林业大学水土保持与荒漠化防治部级重点实验室,北京100083

出　　处：《生态学报》2007年第9期3860-3873,共14页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(30170180);北京林业大学研究生自选课题基金资助项目(05JJ005)~~

摘　　要：用TDR分层对科尔沁沙地东南缘大青沟国家级自然保护区土壤水分进行定位观测,采用多重比较等方法,对土壤水分与环境因子关系的差异进行分析,通过Kriging 插值法用Surfer软件绘制土壤水分等值线图,研究结果表明：土壤含水率在不同的生长季节上变化,表现为夏季＞秋季＞春季,各层间没有显著差异;月均（5、7、9月）土壤含水率的变异系数坡向＞植被类型＞坡位;层均（0～60cm）土壤含水率变异系数坡位＞植被类型＞坡向＞样带.月均土壤含水率从高到低依次为：阔叶林＞矮林＞樟子松林＞疏林草原＞灌丛,不同植被类型各层月均土壤含水率总体上差异极显著,阔叶林远远高于其它植被类型;层均土壤含水率,各植被类型各月份间总体差异极显著,总体趋势从高到低为：阔叶林＞矮林＞樟子松林＞灌丛＞疏林草原,阔叶林明显高于其它类型.月均土壤含水率坡向间总体上差异显著,层间无显著差异;东、西坡与北坡有显著差异,东西坡高于南北坡;层均土壤含水率,同一月份各个坡向间差异不明显, 7月明显高于其它月份;各月总体表现为：东＞西＞南＞北坡.月均土壤含水率除31～45cm外,3个坡位间各层均有极显著差异,下坡位明显高于上坡位与中坡位;中坡位各层月均土壤含水率差异极显著;层均土壤含水率各月份各坡向间差异极显著,下坡位远大于上坡位与中坡位.该区从沟底到坡顶的植被变化逐渐由湿生-中生-旱生逐渐过度,垂直分布明显,这类天然残遗植被与土壤水分及其与环境因子的关系,对于促进周边沙地植被恢复具有重要的参照意义,据此建议了大青沟周边沙地植被恢复模式相应的最低土壤水分阈值,沙地0～30cm土层土壤含水率 9.1%～11.5%、 8.1%～9.0%、6.0%～8.0%;沙地31～60 cm土层土壤含水率 11.1%～13%、 8.5%～11%、6.0%～8.4%,分别适合恢复为疏林、灌丛、半灌丛.Soil moisture distributions in selected transects in the Daqinggou Nature Reserve, the southeastern margin of Horqin sand in Inner Mongolia , China were measured with the Time Domain Reflectometry （TDR） technique. Data were analyzed by the Kriging interpolation method in the SURFER software. We found that the summer months had the highest variation, followed by the fall and spring months. There were no significant differences in soil moisture content among soil layers. The coefficient of variation （CV） of average monthly soil moisture （ May, July, September） were the highest among slope aspects, followed by vegetation types and slope positions. Broadleaf forests had the highest average monthly soil moisture content followed by bosquet, Pinus sylvestris var. mongolica, Savanna, and shrub. Average monthly soil moisture changed significantly in different vegetation communities with the broadleaf forests being on top of the list. The average soil moisture for the entire soil profile varied significantly among vegetation types over time. The ranking from high to low was： broadleaf forests 〉 bosquet 〉 Pinus sylvestris var. mongolica plantation 〉 shrub 〉 Savanna. Soil moisture content in the east and west facing slope was higher than that in the south and north facing slopes. Average soil moisture content of all layers changed little with slope directions in the same month. In east and west facing slopes, soil moisture in different months changed significantly with July being the highest. Overall east facing slopes had the highest changes, followed by west, south, and north facing slopes. The variations of average monthly soil moisture were significant among three slope positions for all layers, except for that of 31 --45 cm depth. Soil moisture of the foothill was much higher than other slope positions. In the middle slope, the average monthly soil moisture in different layers varied significantly. The average soil moisture for the entire soil profile changed greatly among slope positions over tim

关 键 词：土壤含水率 空间分布 土壤水分阈值 大青沟自然保护区 

分 类 号：S152.7[农业科学—土壤学]