毛乌素沙地微地形对土壤凝结水分布的影响  

Effects of Microtopography on the Distribution of Soil Condensation Water on A Sand Dune in Mu Us Sandland

作　　者：郭冰寒 王若水[1] 肖辉杰[1] 郎晓辉[2] 郭玉静 刘涛[1] 

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]寿光市文家街道办事处农业综合服务站,山东寿光262702

出　　处：《水土保持学报》2016年第4期102-109,共8页Journal of Soil and Water Conservation

基　　金：北京高等学校青年英才计划“荒漠生态系统水热传输和交换过程研究”(YETP0752);国家自然科学基金项目“毛乌素沙地凝结水形成的物理过程及其影响因素”(31200538)

摘　　要：为研究毛乌素沙地微地形对土壤凝结水分布的影响,在宁夏盐池荒漠生态系统定位观测站进行野外试验,以当地典型微地形—沙丘为研究对象,采用微渗仪称重法测量沙丘各观测点的凝结水量,同步观测各观测点的气象因子,研究凝结水在沙丘不同坡位的分布及受气象因子影响的变化规律。结果表明:雨前各坡位凝结速率和日均凝结水量均显著低于雨后(P≤0.05)。雨前各坡位的凝结速率差异不显著,平均凝结速率为0.007mm/h,阴坡和阳坡日均凝结水量均随坡位的升高而减小,且与坡位高度呈显著的线性相关关系(P≤0.05),雨前阳坡的日均凝结水量为0.073mm,多于阴坡的0.059mm,坡顶的凝结水量最少(0.041mm)。雨后阴坡的凝结速率和凝结水量随坡位的升高而增多(不包括坡顶),阳坡的凝结速率和凝结水量日均值随坡位的升高而减少,凝结水量与坡位的高度呈显著线性负相关关系(P≤0.05)。雨后阴坡的日均凝结水量为0.310mm,高于阳坡的0.259mm,坡顶的日均凝结水量最少(0.151mm)。雨后,随着时间的推移,各坡位的日凝结水量先增多后减少,第3日凝结水量最多,此后凝结水量逐渐减少,直至趋于稳定。研究结果可为毛乌素沙地的土壤水分平衡和水资源评价提供理论依据,并为该地区的生态恢复提供重要理论支撑。A field experiment was carried out in Mu Us Sandland from August to September, 2015, to investigate the effects of microtopography and meteorological factors on the distribution of soil condensate on a sand dune. The amount of soil condensation water for different positions on the sand dune was measured by microlysimeters and the corresponding meteorological factors were monitored synchronously. The results indicated that the condensation rates and daily amounts of soil condensation water for each slope position before rain were significantly lower than those after rain. The average condensation rate before rain for different slope positions was 0. 007 mm/h and no significance was found between all the slope positions. For both shady and sunny slopes, the amount of daily soil condensation water decreased as the height of slope position increased, and significant linear correlation （P≤0.05） was found between them before rain. The amount of daily soil condensation water on sunny slope before rain was 0. 073 mm, which was more than that on shady slope （0. 059 mm） and the amount was the least on the top of slope （0. 041 mm）. The condensation rates and the amounts of daily soil condensation water on shady slope increased as the height of slope position increased after rain. However the condensation rate and the daily amounts of soil condensation water on sunny slope decreased with the increasing height of slope position and a significant linear correlation （P≤0. 05） existed between them after rain. Additionally, the average daily amount of soil condensation water on shady slope was 0. 310 mm, which was more than that on sunny slope （0. 259 mm） and the amount was the least on the top of slope （0. 151 mm） after rain. The amount of daily condensation water on each slope position increased during the first 3 days after rain and the maximum value achieved on the third days, which then reduced gradually until stabilization. The results of this research can provide theoretical basis for soil water

关 键 词：沙丘 坡位 凝结水 降雨 高度 

分 类 号：P426.3[天文地球—大气科学及气象学]