This chapter is intended to provide some literatures about updating cadastral data changes in cadastral maps. The first session presents some definitions and roles of cadastral data in LIS's. The second session presents the need for updating cadastral maps. Cadastral data is commonly depicted in cadastral maps. Updating cadastral data changes should concern on updating cadastral map. The last session lists several technologies and applications of digital data collection for updating cadastral maps.
Cadastral Data in LIS's
The roles of cadastral data for the LIS development are not a new concept. Toms et al., (1987) stated that cadastral data can be fitted into the context of LIS by two general types of land-related data. First is the "environmental data" that describes natural phenomena such as vegetation, slope, water body, land cover and so forth. Secondly is "parcel-based data" that consist of any information about parcel as a smallest registered unit of land.
According to Williamson et al., (1990) the core of LIS is parcel-based information. He described the Digital Cadastral Data Bases (DCDB) which was introduced in 1990's as a spatial reference for the LIS in Australia and New Zealand. DCDB was adopted in some states using different terms such as Geographical Data Base (GDB) in New South Wales, MAPNET in Northern Territory, Western Australia Land Information System (WALIS) in Western Australia and State Digital Cadastral Map Base (SDCMB) in Victoria. They have a common objective to capture and create a digital database of cadastral for the LIS development. The output of DCDB is a geographical index to visualize cadastral parcel, so a high accuracy is not considered as important as the relative spatial relationship.
Chicocinski (1999) stated that a LIS is constructed by the link of two types of data: spatial and attribute data. Spatial data have a geometric characteristic which are represented by point, line and polygon. Attribute data is descriptive information about features in quantitative or qualitative value. The system can be maintained properly if data are computerized, thus mean all data is in digital format. He took a sample of the evolution of cadastral from "classical" to "modern" which emerged in Poland at 1991 by converting the existing cadastral from analogue to digital form and creating the construction of LIS, more generally GIS. In Poland, the modern cadastral which is a computerized system has to include "real estate data" to determine its cadastral identifier, location, boundary route, land use and classification, technical fitting (main connections), land purpose for planning and attributes of real estate (its surface and values). The main role of the modern cadastral is the ability to integrate with other information resources in the frame of LIS/GIS.
Bishop et al., (2000) defined a LIS is "a GIS which utilizes land parcels as the link to the non-graphic database attributes". According to Bishop's study, the development of Bangkok Land Information System (BLIS) uses cadastral maps as an output of land registration in Thailand; which has been overlaid with large scale rectified photomaps. The land parcel-based map was linked with database attribute from partner organizations (such as electricity, water and telephone) who share the same parcel-based land information (type of building, the owners, location). LIS could be meant as a using cadastral data in the GIS environment (DIBLM & FGDC- Cadastral Subcommittee, 2010). In order to fulfil the requirement of parcel-based information, the cadastral data set managed using a GIS should be concerned on the legal decisions and transactions, legal delineation of boundary, and legally defined rights, responsibilities and restrictions.
Zevenbergen (2002) described the relation between spatial data and descriptive data in cadastre. The link between those data is arranged through parcel identifier. The identifier takes a role as reference for indexing and identifying the parcel in the map and their administrative records in database. Every parcel is defined by a unique parcel identifier. The design of parcel identifier is different among countries depends on their previous or existing cadastral system, time and cost effectiveness and cultural reason (UN/ECE/WPLA, 1996). The changes of a parcel boundary have consequences for updating the map and the parcel identifier. In the Netherlands, for example, it is compulsory to include the parcel identifier in any deed relating to the property transaction (Zevenbergen, 2002).
Nowadays, the classic definition of cadastral data which is consisting of land parcel registration has been expanded to integrate with the other geospatial information. Started in 1980's when USA was introducing a multi-purpose cadastre concept, the cadastre layer has been connected with other geographic information such as building and facilities, cultural resources, government unit and housing (NRC, 2007). Navratil & Frank (2004) stated the most important data in cadastral are spatial (technical data), attributes (legal data) and additional data. Technical data consists of data which is ready to serve 3 (three) tasks: positioning, taxation and planning. Legal data consists of ownership and encumbrances. Additional data hold neither technical nor legal data (e.g. postal code). The variety of cadastral data will be dynamically expanded and should be able to be overlaid with other geographic database to provide extensive information.
Cadastral Map Maintenance
Cadastral Map
Cadastral maps support a significant data in a LIS. Dale (1995) stated that a cadastral map does not only show boundaries of parcels but also additional detail information of resources associated with them (owners, right) including physical structures on or beneath them (house, bunker ), their geology, soils, vegetation and land use. Cadastral maps which are based on large-scale maps can be adapted to general uses; besides as parcel map; such as utilities (pipeline, electricity and telecommunication), roads, canal and ports, land use and classifying land, disaster mitigation, administrative purposes (tax based area), analysis and interpretation of census data and spatial planning.
Level of LIS developments varies in different countries (UN/ECE/WPLA, 1996). Most countries which have a history of formal land administration have already applied a computerized system or are in the process the LIS development. Countries which are building land administration system from the scratch -or almost- have to implement the possibility of optimal solution to deal with the very beginning development without any restrictions to use the existing system. Therefore, the all components of the LIS have to be designed properly regarding to the legislation, time, cost and technology issues, including data collection management for establishing cadastral maps.
Different countries applied different types of land registration system such as deed or title registration, fix or general boundary and systematic or sporadic (Zevenbergen, 2002). Those differences influenced on the type of cadastral maps as a component of cadastral system and the LIS development. Zevenbergen referred to Jo Henssen's classification of cadastral maps based on title registrations. Group of countries (English, German/Swiss and Torrens) has their own standard for cadastral map: English Group uses the large scale topographic map, German/Swiss Group uses a parcel based cadastral map and Torrens Group uses an isolated survey plan. The fix boundary system requires higher accuracy of cadastral map rather than the general boundary system. The systematic system requires a larger coverage of cadastral map rather than the sporadic system. Therefore cadastral map is designed based on the different level of coverage area, level of accuracy and level of information. Cadastral map may serve as a high accuracy of cadastral map or as an index cadastral to identify the general location of parcel-but not its accuracy (Konecny, 2009).
Cadastral maps serve broader purposes in their development such as for taxation, planning and disaster. Colombia and India are examples of countries implementing cadastral map for broader purposes, in addition to several other countries (The World Bank, GLTN, FIG, & FAO, 2010). In Colombia, the cadastral maps also provide the base property of tax: building, usage and ownership; as cadastral belongs to the finance sector. In India, a particular cadastral map named a (village) cadastral map serves for a level-micro planning (natural resources) and impact assessment (disaster mitigation).
Boundaries of parcel as a main element of parcel-based mapping are established using various data collection technology methods (see also Chapter 2.3). Parcel boundaries survey and mapping system are now developing from a survey by a land surveyor (government, private or company) (UN/ECE/WPLA, 1996) to participatory mapping by communities (The World Bank, et al., 2010). Innovations of cadastral survey and mapping are being developed to generate cadastral maps in accordance with the desired information. As a result, cadastral maps can be represented in different digital formats (graphic, numeric, CAD, GIS) and different level of accuracy in accordance with its purposes.
A modern cadastre is normally built based on digital maps and registers (Dale, 1995). Cadastral maps in digital format support a computerized LIS. Several advantages of computerization of maps and registers to build a computerized LIS are effective and efficient data analysis, reduce space of storage, avoid duplication of records and provide a backup data in case of disaster. UN/ECE/WPLA (1996) give an example a project for computerization of cadastral map in Hungary as a key factor to modernize land registration. The existing paper-based maps are converted into digital cadastral maps to provide an accurate large-scale map in a national mapping base which can be rapidly maintained and updated.
The format and the level of accuracy of digital cadastral maps for developing a LIS depends on the various data sources and technologies available in the country concerned. Bishop et al., (2000) took a sample in Thailand as a developing country, the choices to use technologies or the method of GIS/LIS development commonly based on personal interests, vendor promotions, demonstrations from some conferences/seminar or visited develop countries. The difference of format (GIS or CAD), data sources, accuracy and graphic quality of various maps led to confusions among the end users. The problem has been eliminated by composing "base map compatibility level" (see Table 1) that distinguished the map scale with the application. They determined that the most suitable scale map for a base map of LIS in the urban area is 1:1000; if the area has excellent hardcopy of cadastral maps overlaid on large scale rectified photomaps.
Scale
Meters/mm
Resolution
Application
1: 10,000
10
Some roads may disappear
GIS
1: 4,000
4
Some houses may disappear
LIS
1: 1,000
1
No problem in general
GIS and LIS
1: 250
0.25
Too many map sheets
CAD, engineering design
Table . Base map compatibility level (Adapted from (Bishop, et al., 2000)).
Scale map issues related to the purposes of cadastral map (Dale, 1995). Utilities of map presenting different purposes may be defined in large scale, medium scale and small scale. Each scale has advantages depending on the applications. Each nation may determine series of map according to their requirements. This issues affected in the accuracy level. Cadastral map is considered as a large scale map which has to show the various accuracy levels of parcel boundaries. The requirements of geometric accuracy of parcel boundaries in some countries are very precise but in some other countries are far less demanding (UN/ECE/WPLA, 1996). High geometric position requirement is not often a compulsory but the possibility for applying low cost surveying and mapping methods should be always studied. Therefore, the definition of geometric positional accuracy is not only related to the centimetre or millimetre issues but is more regarding the purpose of cadastral map to serve reliable land information.
Positional accuracy is a great concern in the data quality of LIS/GIS in addition to other accuracy issues such as temporal and attribute accuracy, lineage, completeness, and logical consistency (Huisman & de By, 2009). Information about accuracy issues in the metadata becomes consideration to determine the quality of LIS/GIS desired. Positional accuracy in cadastral survey and mapping is corresponding with the errors (Craig & Wahl, 2003). The errors are originating from several sources such as the human, the instrument and the systematic errors. Skills of surveyor in survey and mapping affect the accuracy of observation. The survey instrument offers different level of accuracies depends on the technology and the method applied. Data processing such as adjustment method and mapping technique provide different result of accuracy. One source of error may lead to another error which is called error propagation. Cadastral survey and mapping contains the combination of errors and influence the quality of cadastral dataset. By recognizing the errors, the map can be used in accordance with the tolerable level of accuracy and type of requirement.
Change of Cadastral Map
Cadastral data dynamically change due to population growth, land transaction, land use, conflict, environmental change and disaster. This condition should be coupled with the adequate ability to collect and update data, both the ability of the methods, tools and human resources. The National Research Council (NRC) of United States of America (USA) reported that the change of cadastral data occurs since there are numerous transactions that change the boundaries and its attributes. Cadastral map should be updated regularly due to change of cadastral data caused by a new subdivision, annexations, corrections and other routine modifications. The local government in USA maintains these updating to support the local business processes that require current and accurate information.
The updating of the existing parcel registration is a subsystem of dynamic land registration model (Zevenbergen, 2002). There are 2 (two) varieties of updating: first is transfer of right and second is subdivision or consolidation. The first variety deals with the change due to a transfer of right without change of property unit. The second variety deals with the changes of boundaries of the property unit and usually including the updating of cadastral map. The transfer of the right is the most common case of updating compared with subdivision or consolidation. However, the subdivision and consolidation is also an important process because it is accompanied by the formation of a new property with the change of spatial and attribute data attached on it.
In most cases, the new boundaries as results of subdivision have to be determined by geodetic survey, but in a rare exception cases, an (aerial) photograph can be used to do this in the office as long as the existing topographic features are visible (Zevenbergen, 2002). Take a sample in The Netherlands; the measurement and registration of cadastral boundaries has 2 (two) aims: to enable splitting for creating and registering a new parcel, and to reconstruct boundaries between properties with sufficient accuracy. For the second aim, the reconstruction of a boundary in the field is not based on the cadastral map but based on the original survey boundary taken from terrestrial measurement (Zevenbergen, 2002). Therefore, photogrammetry measurement (ortho-image and oblique-image) is not suited for replacing terrestrial measurement but suitable enough for splitting and creating parcel formation in case of subdivision (Lemmens, Lemmen, & Wubbe, 2007).
Navratil et al., (2004) stated that the changes of cadastral data have to be documented properly. Cadastral documents become representations that describing cadastral data. The cadastral document consists of 3 (three) categories:
1. Legal changes which consist of 3 (three) types: transfer of right, establishment of right and deletion of rights.
2. Changes of technical data, for example the change of number of areas after subdivision and the change of land use.
3. Changes of additional data, neither legal nor technical data, such as postal code.
Heo, Kim, &Kang (2006) have studied the dynamic change of cadastral data. They have a specific definition of spatial and attribute data change. They define the change of cadastral data into 2 (two) categories:
Spatial Data Change; in a parcel-based LIS means changes of parcel boundaries. The typical changes are:
Natural changes: land movement caused by nature (e.g. landslide, earthquake, volcanism)
Boundary relocation: moving of physical objects considered as boundaries such as for resolving legal conflict
Parcel evolution: subdivision and consolidation
Surveying observation: boundary changes affected by change of reference points.
Attribute Data Change; caused by legal and administrative actions such as transaction, public purposes and mortgage.
These changes imply the need for updating cadastral maps. According to their investigation, some requirements for a temporal parcel-based LIS which deals with change of cadastral data are: automatic updating of cadastral maps, spatial data consistency checking, blunder detection and identification of spatial discrepancy.
Updating cadastral data in term of updating parcel boundaries related with the system to identify a parcel: graphic cadastre and numeric cadastre (Zevenbergen, 2002). In graphic cadastre, the updating has to be based on the original notes and sketch of original survey, and then it should be depicted in the cadastral map. In numeric cadastre, the updating is based on the set of coordinates from the boundary point represented a parcel.
Type of cadastral data and cadastral map affected to the updating process. The main purpose of updating is to inform the changes in the field into the database. The equipment and methodology of updating should be compatible with the existing cadastral map and the database. The updating process has to concern on how to provide streamlining and correct information of changes with a certain level of information to maintain the quality of information on the database ((Dale, 1995); (Haanen, et al., 2002); (NRC, 2007)).
Digital Data Collection for Updating Cadastral Maps
A modern LIS applies a modern information technology in data collection, storage, data analysis and dissemination of information. This has to be built using a computerized system that has digital databases and ICT to provide reliable and timely information for the user. In some countries such as USA, Netherlands, Canada and Australia have developed a modern LIS to maintain their cadastral data. However, the common problems for building a LIS in developing countries is the availability of digital data which are up to date in order to have an efficient GIS/LIS operational (Bishop, et al., 2000).
Digital data format allows effective and efficient data management including data sharing and data access. Cadastral maps in digital format can be rapidly maintained and updated. Therefore, analogue format in the paper based (both spatial and textual) should be converted into digital format to meet with computerized system requirements. Analogue format has weaknesses such as large of storage space, lack of updating, difficulties in sharing, weak of security, vulnerable to fraud, possibility to disappear, and slow of access.
A step forward to obtain digital data in the field is linking between field data and office database. Automatic data collection has some advantages: reducing human errors occuring in writing and transcribing data, and facilitating the transfer of data to computer systems (Dale, 1995). Australia has introduced the digital data collection in 1990's. Digital surveying had been integrated in the DCDB project for updating the cadastral information directly to eliminate digitization or numeric input (Williamson & Hesse, 1990). New Zealand, for example, has applied automatic data collection through the Landonline program which has aims to automate the nation's survey and title system (Haanen, et al., 2002). Cadastral survey information can be validated and transferred electronically through the system for updating geodatabase.
Data collection technologies for digital cadastral mapping commonly can be obtained from several methods:
Terrestrial survey (total station, GPS, PDA, tablets PC)
Photogrammetry ( aerial or space imagery)
Scanning and Digitisation (vectorization)
Radar (Radio Detection and Ranging)
LiDAR (Light Detection and Ranging)
Those different technologies are applicable for different nations but depend on their laws, traditions, infrastructures and factors influenced to the adaptation of the methods (Gustafson, 2005). The type of cadastral data and the purposes of the cadastral map also influences the technology used. Digitization and numeric input are common methods to convert paper-based maps into a digital format. Paper maps are scanned and digitized using vectorization method, textual data may be converted by manual input using keyboard. Improvement of accuracy or the completions of the cadastral map are separate processes. Radar and LiDAR equipments are still considered costly. Recent technology of terrestrial survey to obtain a high spatial accuracy is time consuming and costly, therefore the use of photogrammetric methods is considered more rapid and cost effective (Konecny, 2009). Photogrammetric methods have been used in several countries to accelerate the land registration process. Aerial photos or satellite images combined with other data collection technologies served as a base map are offering effective cadastral mapping processes ((Konecny, 2009); (Raju, et al., 2008); (The World Bank, et al., 2010)).
An attempt to utilize satellite images combined with ordinary pens for recording cadastral data changes emerged in Indonesia in 2005. After the tsunami in 2004 in Aceh, the government had a responsibility to update all land records and cadastral maps which had been destroyed through adjudication. The main information sources about the post-disaster situation has been are mostly provided by communities. Combination of local spatial knowledge and geo spatial technology can be very useful re-builded land administration systems (Haroen, Achmad, & Rusmawar, 2006). The new approach used in Aceh is called Community Driven Adjudication (CDA) or also known as Community Base Mapping (CBM).
Before the adjudication, the community makes a "community agreement" regarding the boundaries of the parcels, the ownership and the sketching of all land parcels (basic map). Parties involved in this process are local community, government, donors and NGOs (Non-Governmental Organizations) as a facilitator. The agreement becomes the reference for the National Land Agency (NLA) [1] on the adjudication activities. NLA provided the necessary materials such as administrative and legal forms as well as the basic map based on the satellite imaging. Quickbird panchromatic (0, 61 m resolution) and Ikonos panchromatic (1 m resolution) have been used in the CDA. For the image processing, Ground Control Points (GCP's) have been obtained from GPS measurements; and the Digital ElevationModel (DEM) has been obtained from topographic maps scale 1:25000 combined with terrestrial surveying. The images were plotted in scale 1:2500 on A0-size inkjet glossy papers. Community aided by facilitator identified and demarcated village boundary and parcel boundaries on the top of base map using a pen. Parcel identifier and the owner were simply added inside the parcel or listed on the backside of the map. The identification might took place in the "meunasah" (kind of mosque in Aceh) or in the adjudication base camp. The agreed base map together with other requirements for community agreement was submitted to NLA. Besides as a reference for the field survey, the base map was also used for work planning and work evaluation.
The World Bank study (2010) described the use of photogrammetric method combined with ordinary pens for cadastral purposes in Namibia, Ethiopia and Rwanda. In Namibia, aerial photographs have been applied for updating cadastral maps digitized from handheld GPS for accelerating communal land registration (Kapitango & Meijs, 2010). Based on the concept of the general boundary system, the accuracy to identify the location of boundaries is considered to be sufficient to avoid overlapping claims and to ensure that the right person is allocated to the right parcel. In Ethiopia, Quickbird satellite imagery has been tested as a base map for establishing a parcel index map (Lemmen & Zevenbergen, 2010). The test found that satellite images can support the data collection for land registration by participatory approach, producing field evidences from the field and relatively easy to process. In Rwanda, satellite images and/or aerial photos have being used for demarcating parcel boundaries. The method was suitable when applied in the general boundary principle where boundaries incorporated as "social" rather than "technical" boundaries(Sagashya & English, 2010).
Photogrammetric innovation offers various low-cost data sources, from a low-cost satellite image and Small Format Aerial Photo (SFAP) to free-cost geospatial information provided by Google Earth (Google), Bing Map (Microsoft) or World Wind (NASA- National Aeronautics and Space Administration). Google Map, for example, has covered a whole area in the world with satellite imagery including a high resolution satellite images from Digital Globe. Those data source might be combined with other free-data sources such as a free Digital Terrain Model (DTM) from NASA or from Shuttle Radar Topography Mission (SRTM) for geo-processing. A base map produced by photogrammetry might be combined with other data collection technologies to meet with the requirements. Cadastral data acquisition can be based on free available imageries. The geometric accuracy of boundary points can always be improved later. Cadastral maps based on the free imageries are mostly relevant to object identifications.
Issues considered the need of a high accuracy of photogrammetric products in cadastral maps is always rising. Nevertheless the possibility of photogrammetry to increase the image resolution and the innovation of the method combination provides significant contributions for standard-sized land parcel (spatial units) survey and mapping (Lemmen & Zevenbergen, 2010).
