摘要
纬度和高程是决定我国高山/高海拔多年冻土分布的主要宏观因素,也是建立各类高山/高海拔多年冻土分布模型的首要考虑因素.文章旨在建立一个易于区域对比的、综合纬度和高程双重影响的定量化的等效高程评价指标.以高斯曲线模型为基础,通过对其做导数变换,界定了此宏观尺度模型在中小尺度空间上适用的纬度范围.以位于祁连山区西段疏勒河上游流域的冻土钻孔和实测地温数据作为试验数据,从理论和实证两方面阐述了等效高程的算法,以及用于建立高山/高海拔多年冻土分布模型的可行性.该理论方法的提出,便于从海拔的角度讨论高山/高海拔多年冻土的分布,从而使得不同纬度区的高山/高海拔多年冻土特征的比较得以简单实现,也为纬度和高程之外的其他影响因素的评价提供了基础和平台.
Latitude and elevation are the main macro-factors for determining the distribution of alpine permafrost in the Qilian Mountains,China,and then,are the primary factors for a permafrost distribution model.Purpose of this paper is to construct a general index,the equivalent-elevation,which could combine the double effects of latitude and altitude on permafrost and could be used to the comparison of permafrost distribution in different mountainous areas.Based on the Gaussian curve,the latitudinal range,in which the macro-scale model is suitable to be applied to evaluate the latitudinal effect,is defined through the transformation of the first-order derivative of the curve.Taking the measured mean annual ground temperatures（MAGTs） in the upper reaches of the Shule River as the test data,the calculation approach of equivalent-elevations is demonstrated theoretically and practically,and the feasibility of the approach in construction of permafrost distribution model in this area is also proved.The proposal of the approach contributes to the comparison of alpine permafrost characteristics in different latitudinal areas from the view of altitude,and thus makes this kind of comparison realized easily.In addition,the equivalent-elevations could also be a basis and platform to evaluate other factors＇ impacts on alpine permafrost.Therefore,the equivalent-elevation approach has widespread application.At present,however,the approach should be tested in more areas.
出处
《冰川冻土》
CSCD
北大核心
2011年第2期357-363,共7页
Journal of Glaciology and Geocryology
基金
国家重点基础研究发展计划(973计划)项目(2007CB411502)
国家自然科学基金项目(40871040)
冻土工程国家重点实验室自主课题(Y0SF104001)资助
关键词
等效高程方法
高山/高海拔多年冻土
分布模型
祁连山区疏勒河上游
equivalent-elevation approach
distribution model
alpine permafrost
the upper reaches of the Shule River in the Qilian Mountains
