不同等级道路网络对常宁市景观格局生态效应的影响

针对常宁市域范围,利用GIS和Fragstat软件,通过建立缓冲区并进行情景分析,分析了不同等级道路对景观格局的影响。结果表明:常宁市内一级道路所影响面积最大,二级道路最小,而影响的斑块数目则为三级路一级路二级路高速路,受影响生态面积为水田灌木林地茶园旱地其他建筑用地有林地水体住宅用地其他林地疏林地裸地果园其他园地,受影响斑块数目最高为灌木林地,其次为水田。情景分析表明,随着道路的建设,斑块分维数升高,但总体上,高等级道路对景观形状指数和斑块形状因子升高的贡献率最小。

Ecological effects of different grade road network on landscape in Changning City

Using GIS and Fragstats to establish a buffer,the landscape pattern and ecological process responded to dif-ferent grade roads in Changning City were analyzed in the paper.The result shows that the first grade road has affected the biggest area,and the second grade road has affected the smallest area.The sequence of affected patch number is the third grade roads >the first grade roads >the second grade roads >highway.For the different ecosystems,the effect shows the area order is paddy field >shrub land >tea garden >dry land >other building land >forest land >body of water >residen-tial land >other forest land >open forest land >bare land >orchard >other garden and patch number is shrub land >pad-dy field.Scenario analysis showed that road network development result in the increase of patch complexity and landscape fragmentation.The average patch area decreases while the patch number and fractal dimension increase with the actualiza-tion of road construction and planning,but the expressway affects little in general.