旅游城镇化地区土地利用景观格局指数的粒度效应——以扬州市广陵区为例

Grain Size Effect of Urbanization Tourist Areas of Land Use Landscape Pattern Index——A Case Study of Guangling District of Yangzhou

土地利用景观格局的粒度效应研究,对数字制图、土地利用调查、生态景观格局建设均具有重要的意义,可进一步揭示不同土地利用方式的作用机理,为科学土地利用提供理论支持与实践指导.本文以扬州市广陵区为例,以土地利用调查数据为基础,以景观格局指数和GIS空间分析为手段,对10种空间尺度下的斑块类型水平和景观水平粒度效应进行分析.结果表明:(1)斑块类型水平:随粒度增加,土地利用景观格局指数呈现2种粒度效应:单调下降、无规则变化,水域及水利设施用地、交通运输用地、耕地3种地类的斑块数量、斑块密度受粒度变化影响较大,随时间变化不同土地利用类型的景观格局指数差异不大;(2)景观水平:土地利用景观格局指数变化的粒度效应随粒度增大而出现2种态势:单调下降、波动状下降,聚集指数对粒度变化较敏感,随时间变化表现出相似规律.研究区景观格局的破碎度总体减小,斑块形状愈趋规则,景观各组分分配趋于均匀,景观的斑块多度和异质性也微弱增强,整体的景观格局稳定性得到改善.研究还发现,60 m的空间尺度是研究区范围内最适宜分析粒度.该研究为平原地区的快速城镇化区域精细合理土地利用提供参考建议.

The study of grain size effect of land use landscape pattern is of great significance to digital mapping,land use survey and ecological landscape pattern construction.It can further reveal the action mechanism of different land use patterns and provide theoretical support and practical guidance for scientific land use.Take Guangling District,Yangzhou City as an example,base on land-use survey data,make use of landscape pattern index and GIS spatial analysis as means,then the particle size effect at the patch type level and landscape level at ten spatial scales were analyzed.The results showed that,with the increase of spatial grain sizes changed,on class level,the landscape pattern index has an obvious scale effect,such as the landscape shape index gradually reduced,the percentage of plaque type changed slightly,the number of plaques and plaque density were localized.The number of patches and the patch density of the three types of land,such as water area,water conservancy facilities,transportation land and cultivated land,were greatly affected with the variety of grain size.The landscape pattern index of different land use types had nothing to do with the time change.There is no significant difference in the landscape pattern index between different land use types over time.And the other land,transportation land,grassland was relatively sensitive to particle size changes.The change of landscape pattern index of land use types was obviously different with the change of time.On landscape level,the aggregation index gradually decreased,the diversity of Shannon and the uniformity of Shannon were fluctuating.Generally speaking,the aggregation index was more sensitive to the change of scale.Landscape indices associated with little change with time.The development of land use reduced the fragmentation of the landscape pattern in the study area,and the shape of the patch became more and more regular.The distribution of the landscape components tended to be even,and the degree and heterogeneity of landscape patches also increased weakly.In a word,the overall landscape pattern was stability improving.The study also found that the spatial scale of 60 m was the most appropriate particle size for analysis in the study area.The study provided a reference for the reasonable land use in rapid urbanization in the plain areas.