Detecting dynamic spatiotemporal land use change in linbian watershed, Taiwan after typhoon morakot

On 8th August 2009, the extreme rainfall of typhoon Morakot dumped record breaking rain in southern Taiwan.  The typhoon significantly changed landscape patterns in Linbian Township, Pingtung County, in the southern part of Taiwan. Land use/land cover changes and the direct and indirect effects of these changes have drawn much public attention. This study aims at detecting typhoon Morakot induced land use changes and the dynamic landscape structure changes between 2006 and 2012. Three images from Formosat-2 satellite with resolution of 8 m were used for land use change detection. Geographic Information Systems (GIS), Remote Sensing (RS) techniques are used to quantitatively characterize the spatiotemporal changes of land use and landscape dynamic changes in the study area. Results obtained from the detection analysis show a decrease of vegetation cover by 30%. Other land use types such as river sediment and fallow land show an increased value. Three years after Morakot, vegetation and fallow land show an increasing value and an obvious recovery pattern. The intensity of landscape structure change is much higher between both 2006 - 2009 and 2009-2012 time periods.  These are the transition periods when vigorous land use changes occur. However, the intensity value between year 2006 and year 2012 is small (0.007), very close to zero, indicating probable recovery back to normal conditions in 2012.