中国天山西部季节性森林积雪物理特性  

Physical Characteristics of Forest Snow in the Western Tianshan Mountains,China

作　　者：陆恒[1,2] 魏文寿[3] 刘明哲[1,4] 韩茜[1,2] 洪雯[1,2] 

机构地区：[1]中国科学院新疆生态与地理研究所,乌鲁木齐830011 [2]中国科学院研究生院,北京100049 [3]中国气象局乌鲁木齐沙漠气象研究所,乌鲁木齐830002 [4]中国科学院天山积雪雪崩研究站,乌鲁木齐830011

出　　处：《地理科学进展》2011年第11期1403-1409,共7页Progress in Geography

基　　金：干旱内陆区冰雪资源动态监测与可持续利用评估研究项目(GYHY200706008);新疆现代与历史暖湿化过程及对生态环境影响项目(2005DIB6J113);新疆生态与地理研究所绿洲学者"博士"人才培养计划(0771021);中国科学院"西部之光"人才培养计划项目(RCPY200902)

摘　　要：积雪特殊的物理特性对冰雪水文过程、积雪生态系统、不同尺度的气候系统有重要影响。目前对林下积雪物理特性缺乏系统性研究,因此对天山雪岭云杉林下季节性积雪深度、沉降速率、密度和含水率进行观测分析。结果表明:林下积雪深度小于开阔地;林下积雪沉降速率和新雪密实化率小于开阔地,且稳定期沉降速率小于融雪期。稳定期林下积雪密度小于开阔地,林下雪层密度最大值位于中粒雪层,开阔地则位于粗粒雪层;融雪期则全层密度趋于一致。稳定期林下雪层含水率随深度递减,开阔地雪层最大值出现粗粒雪层;融雪期雪层汗水峰值出现在细粒雪层,新雪层最小,林下雪层由细粒雪层到深霜层始终呈减小趋势,开阔地雪层由细粒雪层至中粒雪层逐渐减小,粗粒雪层至深霜层逐渐增大;稳定期雪层含水率日变化随深度的递减逐渐减小,开阔地大于林下;开阔地的新雪层和细粒雪层含水率的日变化大于林下,粗粒雪层到深霜层则小于林下。The special physical characteristics of snow cover have great influences on the ice-snow hydrological process, snow ecosystem and different scale climate systems. Presently, the physical characteristics of snow cover in the forest are less investigated, so it is meaningful to measure the height, sedimentation rate, density and water content of the seasonal snow in the forest of picea schrenkiana in the Tianshan Mountains. The results show that the snow depth under crown is less than the observation site, the sedimentation rate of snow under crown is less than the observation site, and the rate in the stable period is less than the snowmelt period. The snow density under the tree is significantly lower than the observation site. The snow density of the upper and bottom layers is smaller than the middle layers. The maximum value of snow density is located in the tim-snow layer under the tree, but the maximum value is located in the coarse-grained snow layer in the open area. The snow density in the snowmelt period is greater than in the stable period. In the stable period, the profile of snow liquid water with depth has a single peak in the observation site, the liquid water content of the coarse-grained snow is the highest, and the liquid water content increases with depth under the tree. In the snowmelt period, the liquid water content of the fine-grained snow is the highest, the liquid water content of the newly fallen snow has the minimum value. The snow liquid water content in the open ground decreases with depth from fine-grained snow to mid-grained snow, and increases with depth from coarse-grained snow to depth hoar, while the water content decreases from fine-grained snow to depth hoar under the tree. The diurnal variation is to decrease with depth in the stable period, and the variation of snow liquid water content in open ground is greater than that under the tree. The maximum diurnal variation is in the layer of fine-grained snow and decreases with depth; the liquid water content of new snow and tim-sno

关 键 词：森林积雪 积雪深度 密实化率 积雪密度 含水率 天山西部 中国 

分 类 号：P426.634[天文地球—大气科学及气象学]