HJ 724-2014Technical specification for environmental spatial data processing (English PDF)

3.1 Elevation datum

The starting point of the measurement elevation determined by the average sea level of the particular tide station and the elevation of the origin according to the level determined by the surface.

3.2 Depth datum sounding datum

Calculate the starting plane of the depth of the water.

Beijing Beijing Geodetic Coordinate System 1954 in 1954, China decided to adopt the national geodetic coordinate system (using Krassovsky ellipsoid), in essence, the union of the year of the extension of the 1942 coordinate system.

Xi'an Ge coordinate System Using IAG 1975 international ellipsoid to JYD1968.0 system for the ellipsoid orientation benchmark, the choice of Shaanxi Province Jingyang County Yongle the town is the location of the earth's origin, the use of multi-point positioning established by the earth coordinate system.

3.5 WGS84 (1150) World Geodetic System 84 (1150); WGS84 (1150)

Using the 1980 Earth reference system and BIH1984.0 point to the establishment of a polar reference system and the geocentric coordinate system.

The normal radius of the earth's normal ellipsoid is 6 378 137m, the gravity constant is 3.986 004 418 × 1014m3 - s-2, the flat rate is 1/298.257 223 563, the Earth's angular velocity is 7.292 115 × 10-5rad - s-1.

3.6 National Geodetic Coordinate System China Geodetic Coordinate System.2000; CGCS2000

The origin is in the right hand of the center of the earth. The Z axis is the reference pole direction defined by the International Earth Initiative (IERS) the X-axis is the intersection of the reference meridian surface defined by the International Earth Initiative and the equatorial plane perpendicular to the Z-axis. The Y-axis and the Z-axis and X the axis forms the right hand orthogonal coordinate system. The normal ellipsoid of the earth has a radius of 6 378 137 m and a gravity constant of 3.986 004 418 × 1014m3 - s-2 with a flat rate of 1/298.257 222 101 and an earth angular velocity of 7.292 115 × 10-5 rad - s-1.

3.7 Map projection map projection

According to a certain mathematical law, the reference ellipsoid on the point, the line projected to the way on the exhibition.

3.8 Gauss-Kruger projection

An isometric crossed elliptical projection. Its projection with a central meridian projection into a straight line and the length of the same, the equatorial projection has become Straight line and orthogonal to the central meridian projection line.

3.9 Lambert orthorhombic conical projection lambert orthomorphic conical projection

An equilateral angle equidistant conical projection. The weft is a concentric circular arc, the warp is concentric radius. No angle change Shape, warp length ratio and weft length ratio are equal.

3.10 Spatial data spatial data

Data used to represent information about the location, shape, size, and distribution characteristics of a spatial entity are used to describe all Two-dimensional and multidimensional distribution of the phenomenon of the region.

3.11 Attribute data attribute data

Data describing the quality and quantity characteristics of geographic entities.

3.12 Basic geospatial data

Uniform spatial positioning framework and spatial analysis based spatial data, including measurement control points, the national basic scale scale Column topographic map data and other spatial data produced by mapping industry standards.

3.13 Environmental basic spatial data

Environmental protection departments and other relevant departments to collect, produce and process the spatial location of the environmental business data.

3.14 Environmental thematic spatial data

Based on the basis of environmental basic spatial data, according to the classification of environmental management business or focus on the performance of a subject content of the space data.

3.15 Check all entry inspection

Check the quality of all items required for the quality of the data.

3.16 Overview specific target inspection

Check the specific inspection items required for the quality of the data.

4.1 Elevation datum and depth datum

According to the relevant provisions of GB/T 18315-2001, the elevation reference adopts the "1985 National Elevation Benchmark", special circumstances Under 1. 500 ~ 1. 2 000 can be used independent of the Department of elevation. The depth datum generally uses the theory of the lowest tide.

4.2 Geographic coordinate system

Geographic coordinate system can be used "1954 Beijing coordinate system", "1980 Xi'an coordinate system", "WGS84 (1150) (World Geodetic Coordinate System) or "2000 National Geodetic Coordinate System", of which the number of new productions after July 1, 2008 it is necessary to use the "2000 National Earth Coordinate System".

4.3 Projection mode

Determine the corresponding projection method according to different scale.

A) 1. 1000000 electronic map using Lambert equiangular conical projection, according to 6 ° zoning;

B) 1. 250000 ~ 1. 500000 electronic map using Gauss - Kruger projection, according to 6 ° zoning;

C) 1. 5000 ~ 1. 10000 electronic map using Gauss - Kruger projection, according to 3 ° zoning;

D) 1. 500 ~ 1..2000 electronic map using Gauss - Kruger projection, according to 3 ° zoning. Also according to actual needs, Using any longitude as the independent coordinate system of the central meridian.

5.1 Classification method

The environmental basic spatial data are classified by the line classification method according to the categories,, middle classes and subclasses.

5.2 Categories

The environmental basic spatial data is divided into three categories. basic terrain data, environmental public space data and remote sensing image data.

Figure 1 shows.

Figure 1 Environment-based spatial data categories

5.3 Categories

5.3.1 Basic terrain data classification

Basic terrain data using GB/T 13923-2006 in the classification method, as shown in Figure 2.

Figure 2 Basic terrain data classification

5.3.2 Remote sensing image data classification

The classification of remote sensing image data is shown in Fig.

According to remote sensing image data Environmental public space data Basic terrain data Î.

6.1 Attribute data item classification

6.1.1 Classification principles

According to the natural attributes, social attributes and management attributes of the geographic entity, the attribute data items are classified into basic attribute data items.

Display attribute data items, business-specific attribute data items, as shown in Figure 6.

Figure 6 attribute data item classification

6.1.2 Basic attribute data item

6.1.2.1 Basic attribute data item Description Geographic entity Identifies the attribute, data item of the geometric feature.

6.1.2.2 Basic attribute data items include.

A) Identifier code attribute data item. Used to identify the coding of the geographic entity in the layer.

B) Geometric characteristics Attribute data item.

1) Area of the planar geographic entity. the area of the recording system;

2) the length of the linear geographic entity. the length of the recording system calculation;

3) Perimeter of geographic entity. Record the length of the system calculation.

6.1.3 Extended attribute data items

6.1.3.1 Scalability attribute data items are attribute data used to describe geographic entity class characteristics, description information, relationship characteristics Basic attribute data item Extended attribute data item Business-specific attribute data item Identifier attribute data item Geometric feature attribute data item Classification of attribute data items Description Information attribute data item Associated feature attribute data item Geographic Associated Attribute Data Item Business attribute data item item.

6.1.3.2 Extended attribute data items include.

A) Classification of attribute data items.

1) Classification code. According to the environmental basic spatial data classification and code to determine the geographical entity belongs to the type of generation code;

2) GB code. national or industry standards exist in the geographical entity related category code.

B) Description Information Attribute Data item.

1) Name. The name of the Chinese entity of the geographical entity should generally be determined by the name of the relevant state department;

2) Type. the nature of the nature of the entity that should generally be determined by the relevant state departments shall prevail;

3) Administrative departments in charge of environmental protection. the name of the administrative department of environmental protection where the geographical entity is located, Generally can be detailed to the county level environmental protection administrative departments.

C) Associated Feature Attribute Data Item.

1) Spatial topology description. The extended data item necessary to identify the spatial topology of the local entity;

2) Update Time. Updated to identify this geographical entity.

6.1.4 Business-specific attribute data items

6.1.4.1 Service-specific attribute data Item Description Geographic entity and business management Associated characteristics, attribute data of business management characteristics , Usually refers to the number of business attributes that the specific business unit assigns to the object for the purpose of managing the object According to item.

6.1.4.2 Service-specific attribute data items include.

A) Geographic Associated Attribute Data Item.

1) Geographic information association Unique identification code. unique identification code associated with business-specific data and geographic information;

2) Associated service-specific data items. One or more data items in the business-specific data item as keywords, each A unique identification data item for business-specific data.

B) Business-specific data items. management information for business-specific departments, its identification, scheduling, accuracy, etc. by the business Developed by department.

6.2 Attribute Data Item Name of the field name

6.2.1 Naming methods

Using the Chinese phonetic alphabet combination method for attribute data item field name naming, that is, the field name by the attribute name the first letter of each Chinese phonetic alphabet combination. In the event of an unavoidable repetitive naming, the attribute data item word should be used Paragraph of the Chinese name of the first Chinese characters plus the remaining Chinese characters combination of the first letter of the additional rules, and so on, until the name is no repeat.

6.2.2 Naming constraints

A) the field name does not exceed 30 characters;

B) if the property field with Arabic numerals, and its attribute naming directly in the Arabic numerals;

C) The name of the field that has been defined in the country or industry standard can be used directly.

Data organization and database naming rules

7.1 Data organization

7.1.1 Data organization structure

7.1.1.1 Organizational structure of basic terrain data and environmental public space data

The basic terrain data and the environment public space data are organized according to the structure shown in Figure 7.

A) the database consists of one or more sub-libraries;

B) the sub-library consists of one or more data sets with the same spatial coordinate system;

C) The data set consists of one or more hierarchical data.

Figure 7 Organizational structure of basic terrain data and environmental public space data

7.1.1.2 Organization of remote sensing image data

Remote sensing image data in the database using the raster catalog design, a grid directory to store multiple rasters body.

7.1.2 Data storage and management

Based on the business relational database and spatial database engine to establish the environment spatial database, to achieve environmental basic spatial data Storage and management.

7.1.3 Organization of data sets

The data sets are organized according to the categories of environmental basic spatial data, and the basic terrain data and environmental public space data are Category organization-based terrain data set, environmental public space data set and remote sensing image data set.

7.1.4 Organization of layers and partitioned data

A layer of data should be stored in a single data table for management. In the case of large amounts of data, you can Data table for partition storage, partition in accordance with the spatial distribution.

7.2 Database naming rules

The database naming is performed in accordance with the specific requirements of 4.7.1 in HJ/T 419-2007, named DB_