Research on Ecological Restoration in Wenchuan Earthquake Badly-damaged Regions Based on TM

Wenchuan Earthquake caused great damage to the ecological environment in the disaster-stricken area.In order to know the current recovery of the ecological environment damaged by the earthquake and provide data support for relevant researchers and decision makers,this paper took Landsat TM remote sensing images of June or July during 2006,2008 and 2011 of Wenchuan earthquake disaster-stricken area as data sources,used computerized and artificial visual interpretation method to extract the land uses information of the study area,and combined topographic factors such as elevation and slope to comprehensively analyze the reasons of the change of major ecosystems(farmland,forest and grassland).The results showed that the earthquake damaged the ecosystem of the study area seriously,resulting in substantial shrinking of farmland,forest and grassland by 124.6km2,461.6km2 and 92.3km2 respectively in the study area,and the farmland ecosystem had the most serious loss in Beichuan,Qingchuan and Pingwu counties,while the forest ecosystem lost 285.5km2 in Wenchuan County.The degree of influence on each ecosystem also varies a lot according to different altitudes and slopes.Up to the 2011,the status of the damaged ecosystem had got better in the study area through natural succession and artificial restoration intervention.Farmland,forest and grassland ecosystems had experienced certain degree of recovery,their areas increased 82.8km2,58.3km2 and 174.9km2 respectively.The recovery of farmland and forest ecosystems is not satisfactory while the area of grassland ecosystem had got the most increase,in 2011 which had exceeded the reduced area damaged by the earthquake in 2008,whereas the whole recovery of the ecosystems in research area was not ideal.Further measures of ecological recovery are thus in dire need of.