The bases for the protection of wetland vegetation cover and for the design of vegetation recovery initiatives is an available vegetation cover framework,including the variational characteristics and the investigation of factors influencing vegetation variability.In this paper,using Landsat TM/ETM+ data,we developed a decision framework for the extraction of wetland landscape information from three periods for East Dongting Lake.We then performed analyses of the changes of vegetation on the basis of transfer matrix and the centriods shifting method.Results are shown as follows.(1) From 1993~2002,the areas of forested land,reed land,and carex covered area increased,among them the reed land increased fastest,with an annual growth of 28.93 km2.During 2002~2006,forested land increased rapidly,with an annual growth of 29.655 km2,while the carex area decreased,and reeds remained unchanged.(2) The distribution of centroids of forest,reed and carex in the East Dongting Lake wetland layer by layer are close to the lake center,and entroids of these three vegetation types ceaselessly shifted to the lake centre from 1993 to 2006,among which,changes of forest and reed were more remarkable.
LEI Xuan, YANG Bo, JIANG Wei-guo, YANG Yipeng, Claudia KUENZER, CHEN Qiang
. Vegetation pattern changes and their influencing factors in the East Dongting Lake wetland[J]. GEOGRAPHICAL RESEARCH, 2012
, 31(3)
: 461
-470
.
DOI: 10.11821/yj2012030008