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jacent surveys and will facilitate the eventual automation of the production of cadastral maps.
1.2.1.4   Building and Maintaining Land-Parcel Registers and Data Files
The unique parcel identification number provides a means for linking the cadastral parcel to land-data files or registers that contain information about land ownership, use, value, assessment, and other attributes. Other parcel identifiers may be introduced to facilitate the use of these land-information records and thus form a family of parcel identifiers. These are the codes that permit sharing of land-parcel data among the agencies in each jurisdiction and with other jurisdictions that maintain compatible multipurpose cadastres. A system of identifiers may be coded to indicate the political districts to which each parcel belongs.
1.2.2   Suggested Procedures for Linking Other Land Information to the Cadastre
The report describes successful procedures for connecting other files of land-based information to the basic cadastral reference system. Some of these procedures are feasible only where cadastral files and other records are automated.
12.2.1 Referencing Other Land Information to the Base Map and Cadastral Overlay
Criteria are offered for judging when maps of the boundaries of land characteristics other than those of parcels are needed. These maps establish overlays distinct from the cadastral overlay. Procedures for describing such boundaries by coordinates, and the potential value of these coordinates for the automation of map production, are described. Limitations of describing the locations of land characteristics by grid cells are compared with those of describing boundaries by coordinates.
1.2.2.2   Direct Comparison of Other Land Information with Cadastral Records
The cadastral parcel can serve as a complete and adequate locational reference for many types of social, economic, physical, and administrative data. Thus it is the building block for statistical comparisons among these land characteristics. However, most natural phenomena, and certain other man-made divisions of land, such as for agricultural production, must be attributed to individual land parcels before direct, statistical comparisons can be made with land-ownership information. To do this precisely requires subdividing all records for each parcel that is crossed by the