Juanle Wang1* and Kun Bu2
*1State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100010 Beijing, China
2Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, 130102, Changchun, Jilin Province, China


There are multiple data centers in China under the umbrella of the International Council for Science-World Data System (ICSU-WDS). Although WDS China data centers have made obviously progress and achievements in these years, due to the differences between subject areas and the lack of associative mechanism, WDS-China data portal and metadata exchange system has not built yet. In order to solve this problem, in this paper, the frame of WDS China Common Clearing House was preliminarily put forward and the prototype system was built. On the overall design, given the interaction and independence between data portal and metadata exchange system logically, the basic guiding ideology of design is to enable the two systems to interoperate and exchange information through service interface that conforms to international/national standards. (1) Data portal architecture. An open source management system was built based on TorCMS, releasing data contents, also providing access interface of XML and JSON format. For a great deal of geoscience data information with different dimensions, conceptual model of core metadata plus extended metadata was proposed. The core metadata used traditional relational database to storage. For each field in database there is a metadata item. The extended metadata used key-value way in NoSQL pattern to storage. (2) Metadata exchange system. A separate metadata server was built based on pycsw open standards. The metadata capture module was built based on data harvesting. Through the above development WDS China Common Clearing House has had functions including document releasing and updating, Wiki knowledge releasing and updating, user right management, website full-text retrieval, back-end information statistics, system of online presentation, metadata releasing/push interface, etc. At present the established prototype system has already preliminarily applied in the Renewable Resource and Environment data center of World Data System (WDS-RRE).


The authors would like to express appreciations for support from WDS world data centers in China, National Science & Technology Infrastructure of China, Data Sharing Platform of Earth System Science of China. Thanks the guide and support from Dr. Mustapha Mokrane and Dr. Rorie Edmunds.