Article July 1999.
Mapping In Turkey.
Security at the Top of the Political Agenda.
Located at the junction of Europe and Asia, Turkey is physically a big country with a population of 60 million and a turbulent and fascinating history. Its strategic position is reflected by its front line status as a member of NATO during the Cold War and from the boundaries that it shares with Iraq and Iran which have experienced so much turmoil and war over the last 20 years. Tensions with Greece over Cyprus and the problems experienced with its Kurdish population have also helped to keep defence and security at the top of the country's political agenda. In mapping terms, this has had the result that it is impossible for the visitor to buy topographic maps of the country in the manner that can be done in Western Europe.
By Prof. Gordon Petrie
However this should not obscure the fact that Turkey has developed a large mapping capability based on the latest technology and supported by large numbers of university trained specialists. Overall control of government mapping programmes is exercised by an Inter-Ministerial Committee for the Coordination and Planning of Mapping. The information given below was gained during visits by the author to a number of the main government and commercial organisations concerned with surveying and mapping in Turkey during the first two weeks of March 1999.
General Command of Mapping (GCM)
The maintenance of the country's national control networks and the national map series giving complete coverage of Turkey at 1:25,000 and smaller scales is undertaken by a military organisation, the General Command of Mapping (GCM). This was founded in 1925, a year or so after the establishment of the Turkish Republic, and is located in Ankara. The commander of GCM holds the rank of Major-General. Its staff comprises military officers at the upper level and a mixture of non-commissioned officers and civilian technical staff at the middle and lower levels. As the visit revealed, it has a considerable technical and production capacity. Besides which, it also possesses a large and well maintained map museum with a wonderful collection of surveying and photogrammetric instruments, a fascinating collection of historic maps and atlases and some marvellous paintings produced by early Turkish topographic surveyors.
The whole of Turkey is covered by 5,500 individual topographic map sheets at 1:25,000 scale - a task that was completed originally in 1972. A full revision of the series took place in the 1980s. From these 1:25,000 scale base sheets, smaller scale series at 1:50,000, 1:100,000, 1:250,000, etc. have been derived. Another revision cycle is currently under way with the objective of creating a 1:25,000 scale digital topographic database. Besides its own national mapping programme, the GCM also undertakes work at large scales (1:5,000 1:2,500, 1:1,000) for other government organisations on a repayment basis. It is also responsible for the production of the country's aeronautical charts, but not its nautical charts. These are produced by the Turkish Navy's Department of Navigation, Hydrography and Oceanography which is based in Istanbul.
The GCM operates two Beechcraft 200 and two Dornier Do28 photographic aircraft on which Zeiss RMK-TOP and RMK-A cameras are mainly used nowadays. The organisation also has its own comprehensive photographic film processing facilities and not only undertakes its own photographic missions but carries out aerial photographic work for other organisations.
In order to undertake its extensive mapping and map revision programme, the GCM has a large photogrammetric capability, including around twenty digitized analogue stereo-plotters, five Zeiss Planicomp analytical plotters and seven digital photogrammetric workstations (DPWs), comprising six Autometric SoftPlotters and a single Zeiss Phodis. A Zeiss SCAI scanner is used to generate digital image data from the aerial photographs. There is also a large section that carries out the field completion and editing of the photogrammetric plots.
Cartography & Digital Mapping
The Cartographic Department has a large map production, reprographics and printing capacity. Since 1993, when the build-up of the national topographic databases at 1:25,000, 1:250,000 and 1:1,000,000 commenced, digital map production facilities have been introduced including digitizers and scanners to digitize existing maps and a variety of plotters to generate edit plots and the final film transparencies needed for plate making and printing.
-Topographic & Cadastral General Directorate (TKGM)
Despite the inclusion of the word "topographic" in its title, this large civilian organisation - which traces its origin back to Ottoman times (founded in 1847) - is concerned almost exclusively with land registration and with cadastral surveys and mapping. Its central Directorate is located in Ankara and its importance can be recognised by the fact that it comes directly under the Prime Minister's Office. In organisational terms, it is extensively decentralized with 60 regional directorates, 350 cadastral survey offices and 1,001 local or district land registry offices. Needless to say, it is a very large organisation employing 14,000 people. Of these, 4,000 are university graduates in law, etc. (including 850 surveying engineers) and there are also 4,500 trained and qualified technicians. There are 50 million individual property records in the land registry system. So far, 35 million of these have been entered into the Directorate's computerized record system.
-Cadastral Surveying & Mapping
The surveying staff have access to modern equipment, including 400 total stations that are distributed throughout the local cadastral offices. When the digital survey data arrives from the field, it is processed immediately on PCs running the DCS software from Germany and equipped with plotters to generate check plots. 350,000 individual cadastral plans are maintained by TKGM. These are now being digitized using tablet digitizers and scanners.
-Aerial Photography & Photogrammetry
For its aerial photographic work, TKGM possesses two Britten-Norman Islander aircraft equipped with a Zeiss RMK-A and three older Wild RC10 cameras. It also possesses a film processor, an electronic dodging printer and a photographic enlarger. Besides its own aerial photographic missions, it also undertakes work for other government departments and commercial companies. Formerly the organisation had a major photogrammetric capability in-house, including 20 analogue stereo-plotters that were employed on its cadastral mapping programme. With the decision to outsource its photogrammetric compilation work to the private sector, this capability has been reduced to a single Zeiss Planicomp analytical plotter and a Zeiss Phodis DPW together with a Zeiss SCAI scanner.
General Directorate of Forestry
This is one of five Directorates that come under the Ministry of Forests. It has a staff of over 30,000, of which 4,000 are university trained forest engineers. Turkey has extensive areas of forest, amounting to 200,000 sq. km which represents over 25% of the country's land area. The General Directorate has a mapping unit based in Ankara whose task is to produce forest management maps. These mainly take the form of transparent film overlays that can be placed over the standard topographic maps produced by GCM. The unit has 70 staff with a very high proportion of women, most of whom are graduate forest engineers.
The aerial photography that is utilized by the unit is acquired in the form of colour infra-red (CIR) false-colour film usually taken at 1:15,000 scale by GCM or TKGM. Contact prints are generated from this photography for interpretation purposes. However, since this is a positive reversal film, no attempt is made to produce diapositives from it. Instead the original film is simply cut up into individual frames and used in the subsequent photogrammetric operations.
The photo-interpretation is carried out by the forest engineers using Wild APT2 stereoscopes equipped with zoom magnification and with direct annotation of the interpreted detail on the hard-copy photographic prints. The interpretation process delineates the forest areas; identifies and classifies the different tree species; estimates the tree crown diameter and the degree of canopy cover and closure; and identifies the forest roads and the areas of cultivated land.
After the photo-interpretation work has been completed, the annotated paper prints are scanned at the low resolution of 200 dpi using two Sharp JX-600 scanners. The digital image data is then transferred for stereo-plotting which is carried out using manual feature extraction on ten DVP digital stereo-plotters. The control point data required to set up each stereo-model is generated by aerial triangulation of the film positives using two Kern DSR15 analytical plotters and the Leica AETRI module. The ground control points (GCPs) are taken from the 1:25,000 scale base maps. The adjusted aerial triangulation data is also transferred to the DVPs. The digital map data generated on the DVPs is then transferred to three workstations running the Kern INFORMAP software on which the editing of the data and the generation of edit plots and the final overlay plots is carried out.
-Forest Information System
A new project has just commenced that is designed to produce data for cadastral and forest planning purposes. This is a pilot project that has been financed by credits from a group of Finnish banks. The main contractor for the supply of the system is the Enso Forest Development company from Finland. The system is based on PCs running under Windows NT and utilizing ARC/INFO, ArcView and Corel Draw software.
Two of the larger commercial survey and mapping companies were also visited. The first of these, MNG Bilgisayar, forms part of the large MNG group of companies that are principally engaged in architectural design and building construction. They occupy a striking high-rise building located in the southern part of Ankara. MNG Bilgisayar has an annual overturn of US$8 million and employs 100 people. Most of its activities are in Turkey where it mainly carries out large-scale mapping at scales between 1:1,000 and 1:5,000 for government agencies and municipalities. It has also carried out some mapping work abroad in Germany, the Middle East and Latin America as a sub-contractor to the German Hansa Luftbild company. The aerial photography for its Turkish contracts is mainly carried out by TKGM.
MNG carries out all its field survey control and completion work in-house. For its photogrammetric operations, it deploys eight Intergraph IMA analytical plotters and four Autometric SoftPlotter DPWs, together with a Zeiss SCAI scanner. Aerial triangulation is carried out using the Autometric Block Tool with the Inpho PAT-B-GPS package used for block adjustment. The feature extraction and map compilation is carried manually on the stereo-plotters. This is supplemented by field completion and extensive editing and quality control operations using MicroStation. The final data is mainly delivered to customers in Bentley DGN format.
The company also carries out GIS software system development, both for its own in-house purposes and on behalf of municipalities. This is mainly based on the use of Bentley's MicroStation GeoGraphics software.
This company is based in Istanbul and is housed in a small part of the enormous Perpa shopping and business centre (reputedly the second largest building in the World after the Pentagon in Washington). It employs 180 people and appears to work very closely with the city's municipality, for which it is currently carrying out large-scale mapping of the whole conurbation at 1:1,000 scale. It also carries out mapping work for other municipalities, highway and public works departments and re-allotment projects.
The company operates a Beech C90 aircraft equipped with a Zeiss RMK-TOP camera and the CCNS IV GPS-based navigation system. It has its own film processing facility and an electronic dodging printer to generate diapositives and paper prints.
On the photogrammetric side, the company utilizes DPWs exclusively. Indeed it is one of the largest sites for DPWs in Europe. Its current capacity comprises 16 Zeiss Phodis and 6 LH Systems SOCET SET units, all based on the use of SGI graphics workstations. These DPWs are operated 18 hours per day. The digital image data is generated using a Zeiss SCAI scanner. For aerial triangulation, two semi-automatic systems - Zeiss Phodis-AT and LH Systems HATS - are available to carry out point transfer and measurement. The Inpho PAT-B-GPS package is used for block adjustment.
EMI Harita has two subsidiaries that are concerned with GIS activities. The first is called GISMap and is mainly concerned with the structuring of data that takes place after the editing of the photogrammetrically produced data using MicroStation. In this way, the data is made GIS-ready for delivery to customers - principally in the public utilities (water, electricity, gas) and in planning departments within municipalities. The second company is called Computer System Architecture and is concerned with the development of GIS application software tailored specifically to meet customers' requirements. These currently include a system concerned with the tracking and monitoring of fleets of trucks and a work order management system for use by municipalities.
Professor G. Petrie. Department of Geography & Topographic Science, University of Glasgow, Scotland, UK