RESEARCH OF SPATIAL AND TEMPORAL VARIATIONS OF WETLAND IN PEARL RIVER ESTUARY (1978 approx 2005)

摘要

During the period of 1978approx2005, substance changes have taken place of coastal wetland in Pearl River Estuary as the result of interaction of human and natural factors. To investigate the spatial and temporal variations of coastal wetland in Pearl River estuary, Landsat-MSS images in 1978 and Landsat-TM images of 1995 & 2005 year were processed, and wetland database of the three periods was established based on these remote sensing images. The result showed that: (1) area of natural wetlands decreased while the area of construct wetland increased distinctively; (2) in the period of 1978approx1995, coastal wetland area decreased by 3.3percent, while it decreased by 18.3percent in period of 1995approx2005; (3) Among 6 administrative districts in the study area, the wetland dynamic degree can be sorted in a descending order as: Zhuhai, Shenzhen, Macao, Dongguan,Zhongshan and Guangzhou; (4) the centroids of wetland in Pearl River Estuary coastal zone moved to north by a linear distance of 0.6 km during 1978approx2005, and move to south east during 1995approx2005 by a linear distance of 6.1 km; (5) according to the changes of coastlines in Pear River Estuary, area of sea reclamation during 1978approx2005 along coastline inland in Zhuhai, Macao, Zhongshan, Guangzhou Dongguan, Shenzhen are 12439.29, 502.60, 2946.45, 5372.21, 1815.96, 6317.88 hectares respectively.