| WebGIS systems have being widely used to improve water resources management for the last decade. Due to the poor interoperability, traditional WebGIS technologies were not capable to serve multi-subjects spatial layers in intergraded way, which resulted in the disseverance of multi-profiles of basin features. Anew prototype system composed of several WebGIS systems, was developed, with which layers from different WebGIS systems were overlaid seamlessly based on WMS interfaces.Although commercial WebGIS systems have showed great performance on the interactions with their property clients, normally software interfaces of commercial WebGIS systems are not open. Basin features have multi-profiles, which requires the integrated representation of spatial layers, while spatial data are widely distributed and heterogeneous in water sector, so it would be very difficult, if not impossible, to integrate different commercial WebGIS services. OGC has released a set of widely accepted Information Framework and OpenGIS Services Framework (OSF) to promote geospatial interoperability. The emerging Web Service platform was chosen as the foundation of OSF, which is called OpenGIS Web Services (OWS). WMS, one of OWS implementation services, defined the interfaces and encodings when a service instance produced georeferenced maps. In that sense WMS acts just as georeferenced map services API on Web platform. Based on WMS, a new WebGIS schema that certain client can access layers on several WebGIS servers came to be available.In prototype system two WebGIS systems were developed, of which one used UMN MapServer as a remote WMS compliant system. Local WebGIS system served infrastructure layers of Jiangsu province, while remote WMS system served water features. Conclusions were drawn from the experiment, that geospatial layers from two servers can be overlaid successfully regardless of the heterogeneities of WebGIS systems, geospatial data models, coordinates reference systems, and projections, etc.
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