Spatial-temporal process and characteristics of vegetation recovery after Wenchuan earthquake: A case study in Longxi River basin of Dujiangyan, China.

Abstract

Quantitative evaluation on the vegetation recovery after the earthquake is of great scienti-fic significance for local ecological system rebuilding and regional social-economic sustainable deve-lopment. By taking the Longxi River Basin in Dujiangyan of Sichuan Province as an example, and employing the MODIS-NDVI time-series data, this paper illustrated the dynamic changes of the ve-getation cover rates in Longxi River basin before and after the 5.12 Wenchuan Earthquake by using Landsat data, and then time-space characters of the recovery rates of the damaged vegetation was quantified structurally by referring the factors of river-system and terrain. The results showed that the recovery of impaired vegetation coverage worked well from a holistic point of view, but the response of vegetation coverage to earthquake disaster showed a lagging-phenomenon. The recovery rate of damaged vegetation was significantly correlated to its distance to surrounding river systems, elevation, slope degree, and slope aspect. This finding could provide technical supports for decision-makers to intervene the recovering process after earthquake.