Abstract: Ecological diversity refers to a combination of the richness and evenness of an investigation object.Based on this,the widely used model,Shannon model,and a recently developed model,Scaling ecological diversity model,were theoretically analyzed in this paper.It was indicated that Shannon model had many limitations,e.g.,it could be available only when the number of each type of investigation object was more than 100,did not include any information of scale,and could not express the richness of diversity.In other words,Shannon model could only express the evenness of diversity.A case-study in Fukang of Xinjiang Uygur Autonomous Region showed that the richness and Shannon evenness were always resolution-dependent,while the ecotope diversity calculated by Scaling ecological diversity model was resolution-independent when the spatial resolution ranged from 30 m×30 m to 150 m×150 m,and strictly increased when the spatial resolution ranged from 150 m×150 m to 480 m×480 m.

Key words: Sanjiang Plain, Wetlands, Ecological fragility, AHP