Surface deformation detected by ALOS PALSAR small baseline SAR interferometry over permafrost environment of Beiluhe section, Tibet Plateau, China

摘要

The evolution of permafrost and the active layer is highly related to biological diversity and climate change because of its feedback effects involving water and carbon storage. In this study, we firstly examined the relationship of active layer variation, geomorphological processes and anthropogenic activities by means of small baseline synthetic aperture radar interferometry in Beiluhe, Hoh Xil natural reserve in Tibet Plateau (TP), China. 3.5-Yr observation span of L-band ALOS PALSAR data (June, 2007 to December, 2010) was used. The estimated surface displacements (primarily in the range of -20mmyr~(-1) to 20mmyr~(-1)) and time-series implied evolution of the active layer and permafrost beneath. The motion trend along slopes was complicated due to the geomorphological processes, and thus interdisciplinary interpretations were needed. Anthropogenic influences on this frail permafrost environment were significant, as evident from the remarkable surface settlement along the embankment of Qinghai-Tibet Railway. It is crucial and necessary to monitor this permafrost plateau owing to the consequences arising from a combination of factors related to climate change, geo-hazard prediction, nature conservation and regional sustainable development.