Study on the forestland and tree species landscape structure based on GIS in Changfeng county.

Based on forest resource inventory data of Changfeng county from 2003 to 2006,the characteristics of forestland and tree species landscape structure were analyzed using the following indices:patch dimension,patch shape index,patch density and landscape diversity,through GIS(geographic information systems) technology.The results showed that the types of foresland increase from 4 to 5,and the arboreal pure forest land is in the dominant position among the forestlands;the forest land patch shape is in regularity.The mean patch shape index of arboreal mixed forest land is the biggest,and its mean patch circumference is also most complex.There are 10 tree species groups,in which,poplar landscape is the dominant one.During this period,poplar landscape increase by 1967 patches.The construction of tree species is unitary;the mean patch dimensions of tree species have change little and the patch shape is more regulation;the mean patch circumference of tree species is more complex;the patch proportion of poplar landscape and patch density increase,but the correspondent change trends economic fruit forest is actually opposite.