摘要
青藏高原工程走廊多年冻土是地气系统相互作用的产物,气候环境决定了其分布的宏观格局,但局地因素如坡向等,在一定条件下,对小区域多年冻土的影响往往会超过大气候背景。通过Pearson相关性分析,选取了对青藏高原工程走廊多年冻土分布影响较大、在GIS技术支持下较容易量化的坡向,结合区域内29个钻孔点的长期地温监测数据,建立了年平均地温与高程、纬度及坡向之间的多元线性模型。根据青藏高原冻土工程地温分带指标,制作出了走廊内符合实际的冻土分布图。运用随气候变化的响应模型,预测了走廊内50 a后多年冻土将发生较大的变化:1.低温稳定区、低温基本稳定区的空间分布面积逐渐减小,分布界线向高海拔迁移;2.高温不稳定区较大范围地向高温极不稳定区转化;3.高温极不稳定区将处于长期的退化过程。
The permafrost in the Qinghai -Tibet Plateau is resulted from the interaction of the atmosphere-earth system. The atmosphere controls the macrostructure of the permafrost. 1 owever, some local factors such as slope- aspect, also greatly affect the permafrost status. According to the conseqt ~nce of Pearson Correlation Analysis, we select some factors greatly influencing the permafrost distribution in a section from the Chumaer River to the Feng- huo Mountain in the Qinghai -Tibet Engineering Corridor. The factors that can be easily quantified by GIS were latitude, elevation and slope-aspect. Based on records of the mean annual ground temperature from 29 boreholes in the section, the relationship model between the mean annual ground and the elevation, latitude and slope-aspects is constructed using regression analysis method. When multiple correlation coefficient is significant with a value of 0. 936. Then a simulated map of permafrost distribution is produced through the indices for cold region engineering purpose. Every zone＇ s area is also calculated. Then, we predict the permafrost change in the study area after 50a, supposing the air temperature might rise 1.25~C. The prediction shows that the low temperature stable zone and sub-stable zone might shrink from 14.98%, 15.96% at present to 4.81%, 14.45% respectively. At the same time, the high which might be temperature unstable zone might greatly transform into high temperature extreme unstable zone, in the degradation. Such changes will influence the local infrastructures seriously in future.
出处
《山地学报》
CSCD
北大核心
2013年第2期226-233,共8页
Mountain Research
基金
科技部973计划项目(2012CB026101)
国家自然科学重点基金项目(41030741)
国家自然科学创新群体(41121061)
冻土工程国家重点实验室自主项目(SKLFSE-2Y-07)资助~~
关键词
青藏高原
多年冻土
坡向
模型
趋势
the Qinghai - Tibet Plateau
permafrost
model
slope-aspect
trend
