Abstract: In this paper,the forestland in Wuzhishan City was taken as a research subject and the AHP method,Principal Component Analysis and GIS technology were used for the dynamic research on the landscape pattern and ecological sensitivity to the forestland of Wuzhishan city in the years of 1998,2003,2007 and 2012.The results showed that:1) The ecological vulnerability of forestland types in 2012 was:economic forest>Eucalyptus>bamboo>shrub economic forest>broadleaf mixed forest>other hardwood category>other shrub forest>coniferous forest.The area of forestland in terms of slight,light,moderate,heave and extreme vulnerability occupied 13.19%,18.47%,19.58%,23.02% and 25.74%.2) The ecological vulnerability of forestland types in the city increased first and then slightly decreased during 1998 to 2012.Human disturbance is the main driving factor to this change in ecological vulnerability of forestland.3) The ecological vulnerability of forestland in the city had a correlation with the degree of polymerization,and had a significant correlation with patch density index and connection index.The variation trend of the ecological vulnerability of forestland is polarized first,become stable and then deteriorate rapidly.4) Topography is the source which affects the distribution and change of ecological vulnerability of forestland in the city.

Key words: forestland, ecological vulnerability, landscape pattern, dynamic change