Abstract:
Cadastral maps in Pakistan are sketched on paper or cloth having no cartographic standards, geographic coordinates, datum, angles and unique survey numbers. Attributes related to cadastral mapping are recorded on separate paper based registers. The objective of study is to leverage geospatial technology to automate, audit and standardize the manual cadastral mapping in Pakistan. The study employs High Resolution Satellite Imagery (HSRI), Participatory Geographical Information System (PGIS) and Global Positioning System (GPS) for on ground identification of revenue boundary marks. The HSRI and existing parcel measurements aided in improving the accuracy of GPS surveyed boundary marks location compared to their original on ground location. Re-modelling of Land Administration Domain Model (LADM) Spatial unit package, its sub packages and proposed unique codes for parcel survey numbers is suggested to standardize the cadastral data preparation. An automated approach is adopted to create the parcel geometry using existing parcel measurements and boundary marks. The methodology helped in creating 62% of parcels automatically, 17% semi automatically and rest of 21% adjusted manually. The integration of field book attribute records and parcel geometry paved the way for digital audit which revealed many discrepancies in cadastral record. The geometric construction of land parcels revealed about 8.79 acres as extra compared to officially notify total area of the parcels. The area discrepancies arise due to current field book which is duplicate copy prepared without field survey. The proposed methodology is valid only for the parcels having rectangular (square) survey system employed in Pakistan
