National information infrastructure and national spatial data infrastructure

National Information Infrastructure

National Information Infrastructure (NII) is a complete network system consisting of communication network, computer, database and daily electronic products, which can provide users with large capacity of information at any time. At present, the widely used information infrastructure in the world is the Internet, and Web service is undoubtedly the most important application on the Internet. National information infrastructure will promote economic development, with the expected benefits as follows：

1. Promoting the development of new technologies, such as semiconductors, high-speed networks and their software；

2. Forming large-scale industries and accelerating economic development；

3. Promoting the development of e-commerce；

4. Assist in solving medical care problems and reducing medical expenses；

5. Promoting scientific and technological research；

6. Promoting education；

7. Serve the citizens of the whole country。

National Spatial Data Infrastructure

National Spatial Data Infrastructure (NSDI)) is another national information infrastructure. Its purpose is to coordinate the infrastructure for collecting, managing, distributing and sharing basic geospatial data sets. Spatial data infrastructure is mainly composed of four parts: data interactive network system, basic data sets, regulations and standards, and institutional system. From a technical point of view, its main contents are: spatial data standards, basic spatial framework data, spatial data exchange network and metadata, etc。

According to the calculation, 80% of the world’s data include spatial reference data content, that is to say, geographic information has penetrated into various departments and disciplines. Many organizations and units need to use spatial data for business production or scientific research. In this way, data standards should be established, and the corresponding systems and regulations should be used to guide the input and management of spatial data so as to realize data sharing, further promote the use of geographic information, so that geographic information application units do not need to duplicate the input of spatial data and reduce their work costs. It is the greatest benefit of building national spatial data infrastructure. On the other hand, the construction of digital earth is a high-tech and difficult project, which requires a lot of funds. The national spatial data infrastructure can be regarded as an important first step of a country’s digital geoengineering, because it constructs a spatial database and establishes corresponding policies, regulations and standards, which is also necessary in the framework of the realization of digital earth。

At present, the construction of NSDI in China includes the collection, management, coordination and distribution system and organization of spatial information; spatial data collection system; geospatial data set Metadata and spatial information exchange network; basic spatial framework data and geospatial data standards。

1. Systems and institutions for collecting, managing, coordinating and distributing spatial information: formulating the planning, policies, standards and regulations of national spatial information facilities, establishing hierarchical institutional system, coordinating the cooperation and rights of various departments (including surveying and mapping, land, environment, development, agriculture, etc.), researching related technologies, and carrying out project management, etc。

2. Spatial data collection system: A remote sensing satellite system consisting of a series of remote sensing satellites or small satellites。

3. Geospatial Data Set Metadata and Spatial Information Exchange Network: they include National Basic Geographic Information Center, Chinese Academy of Sciences, National Information Center, Peking University and so on, have carried out research on Metadata standards, but they still need to be in line with relevant international work. Spatial information exchange network mainly uses national information infrastructure, including China Public Packet Exchange Data Network (CHINANET), China Internet, Golden Bridge Network (CHINAGBN), Education and Scientific Research Network。

4. Basic Spatial Framework Data: The National Bureau of Surveying and Mapping has carried out the input and database construction of basic spatial framework data, including the national 1:250,000 topographic database, the national 1:250,000 topographic names database, the national 1:1 million digital elevation model, the national 1:1 million topographic database, the national 1:1 million topographic names database, the national 1:1 million digital elevation model database, the national 1:4 million topographic database, and the whole country. China’s 1:4 million gravity database, 1:50,000 4D product series in some areas, 1:10,000 4D product series in seven major rivers of the country, and so on。

5. Geospatial Data Standards: The State Bureau of Surveying and Mapping and other relevant departments have established a series of spatial information standards, which have been issued and implemented, including “Geographic Grid”, “Land Basic Information Data Classification and Code”, “Forestry Resources Data Classification and Code”, “National River Name Code” and so on. In addition, standards involving spatial data exchange formats, ellipsoids and projections are also being developed。