Semantic inconsistency between geographical classification schemes is believed as the most serious problem for heterogeneous geographical information systems to implement semantic information sharing.Since 1980’s four standard Chinese geographical classification schemes have been constructed

i.e.Classification and Codes for the National Land Information（GB/T13923-1992）

Classification and Codes for the Features 1∶500

1∶1000

1∶2000 Topographic Maps（GB/T14804-1993）

Classification and Codes for the Features 1∶5000

1∶10000

1∶25000

1∶50000

1∶100000 Topographic Maps（GB/T15660-1995）

and Classification and Codes for the Features 1∶500

1∶1000

1∶2000 Topographic Maps for Urban Fundamental Geographical Information System（CJJ100-2004）.Individual special geographical classification schemes are normally constructed for specific geographical information systems.GB/T13923-1992 is a general and basic standard geographical classification scheme.All other geographical classification schemes are suggested to be compatible with GB/T13923-1992.Geographical information systems are usually inconsistent in terms of their content and geographical classification schemes.A single geographical concept might be represented in different ways so that geographical information systems cannot initially implement semantic information sharing.Semantic mapping is considered as a tool to state semantic relations between entities belonging to different classification schemes.It has been proven to most effectively resolve semantic heterogeneity between geographical classification schemes.Although intellectual methods can attain good effects

there are still problems if there are insufficient time

money and experts.This paper firstly describes a method for identification of entities from different geographical classification schemes.Based on semantic relations

parameters for the qualitative and quantitative analysis of their semantic consistency are defined.And then the basic architectures and coding measures of standard geographical classification schemes are compared and analyzed.The results of the quantitative comparison between GB/T 13923-1992 and other standard schemes show that GB/14803-1993 and GB/T 13923-1992 have the best semantic consistency.The results of the quantitative comparison between common-scale and different-scale standard schemes show that GB/14803-1993 and CJJ100-2004 have the worst semantic consistency

but GB/T15660-1995 and GB/14803-1993 can achieve better semantic consistency.Finally

some suggestions are given for construction and modification of Chinese standard geographical classification schemes.For example

standard schemes should define identical main classes and item names

authorized semantic mapping of standard geographical information schemes should be published

and ontologies may be able to solve the problem of semantic inconsistency between photographical geographical information schemes naturally and economically.