摘要
为探究青藏高原近年来冻土退化情况,使用MOD11A1地温数据和Stefan模型,在1 km的空间尺度上模拟了青藏高原2000~2020年的多年冻土活动层厚度(A_(ALT))。结果表明,近20年来青藏高原多年冻土A_(ALT)平均值达到2.43 m,A_(ALT)较厚的地区主要分布在多年冻土区的边缘,而A_(ALT)较薄的地区主要分布在大片连续多年冻土区的内部。A_(ALT)增厚区多呈面状、集中分布,主要分布在气温较高的青藏高原西部,且A_(ALT)与气温随时间的波动情况相似,都有增加趋势,说明A_(ALT)可能受气温的影响;而A_(ALT)变薄区多呈点状、零散分布,主要分布在青藏高原东部和西南部分地区。青藏高原上不同植被类型的A_(ALT)从大到小依次为灌丛>林地>草地>永久湿地;在灌丛地区,A_(ALT)与N_(NDVI)呈显著负相关关系。
In order to explore the degradation of prmafrost on the Qinghai-Tibet Plateau in recent years,the thickness of permafrost active layer(A_(ALT))from 2000 to 2020 was simulated at a spatial scale of 1km based on MOD11A1 earth temperature data and Stefan model.The results show that the average active layer thickness on the Qinghai-Tibet Plateau is 2.43 m in recent 20 years.The regions with thicker active layer are mainly distributed in the edge of permafrost regions,while the regions with thinner active layer are mainly distributed in the interior of large continuous permafrost regions.The thicken regions of permafrost active layer are mostly planar and concentrated,and are mainly distributed in the west of Qinghai-Tibet Plateau,where the temperature is relatively high.Moreover,the fluctuation of active layer thickness and temperature with time is similar,and both have an increasing trend,which indicates that the thickness of frozen soil active layer may be affected by air temperature.The thickness thinning areas of permafrost active layer are mainly distributed in the eastern and southwestern part of Qinghai-Tibet Plateau.The area with thicker active layer is often distributed in the place with higher air temperature.The A_(ALT) of different vegetation types on the Qinghai Tibet Plateau was shrub>forest>grassland>permanent wetland from large to small;In shrub areas,A_(ALT) and N_(NDVI) showed a significant negative correlation.
作者
朱寒江
王卫光
ZHU Han-jiang;WANG Wei-guang(College of Hydrology and Water Resources,Hohai University,Nanjing 210098,China)
出处
《水电能源科学》
北大核心
2022年第4期175-178,195,共5页
Water Resources and Power
基金
国家自然科学基金项目(51979071)。
关键词
青藏高原
多年冻土
活动层厚度
气温
植被
Qinghai-Tibet Plateau
permafrost
active layer thickness
air temperature
vegetation
