d4647ebc68bd8e3cf9b286ae582d2983.ppt
- Количество слайдов: 43
United Nations Regional Workshop on Census Cartography and Management Lusaka, Zambia 8 – 12 October 2007
The Central Statistics Office Cartography Unit Mauritius Y. Buxsoo October 2007
OUR MISSION To provide timely, relevant and reliable statistics, consistent with international principles and standards, for effective decision-making and monitoring
OUR VISION To be a key provider of worldclass statistical information
REPUBLIC OF MAURITIUS § The Republic of Mauritius is a group of islands located in the South West of the Indian Ocean. § Total Area: 2040 Km 2 § Population: 1. 2 million § Population Density: 610/ Km 2 (One of the world’s highest)
Location of Mauritius
CENSUS HISTORY § 1 st population census dates back to the 18 th century (year 1735) § CSO was established in the year 1948 § The last census was carried out in the year 2000 § The next census is planned for the year 2010 Census is conducted according to provisions of the Statistics Act
CARTOGRAPHY UNIT - History § The Cartography Unit was set up in the mid 1970’s § Computerization of the unit started end of 1998 § GIS was introduced in October 2002
CARTOGRAPHY UNIT Director Division 3 Deputy Director Principal Statistician Cartography Unit 1 Senior Statistical Officer 5 Statistical Officer
CARTOGRAPHY UNIT What do we do? § § § § Prepare, update and produce Enumeration Area (EA) maps for censuses & surveys Carry out field work to update existing maps Assist in the preparation and conduct of censuses and surveys Prepare Primary Sampling Frame for surveys Estimation of population & households data relating to regions Produce thematic maps and migration analysis report Create spatial database using GIS applications
Mapping Activities Mapping activities of the unit: Digitize base maps (dated 1997) purchased from Ministry of Housing and Lands § Boundaries of all administrative boundaries have been digitized on a different layer in Auto. CAD and subsequently translated to Map. Info to produce thematic maps § Boundaries of all EAs (of lower spatial level) have been digitized in Auto. CAD § Land features such as roads, rivers, street names etc, each kept on separate layers, for EA maps are currently being digitized in Auto. CAD and are expected to be completed by end of 2008 §
Our Collaborators § Ministry of Housing and Lands (MHL) is the body producing National Spatial Base Maps and provides morcellement maps § National Housing Development Company (NHDC)provides plans for new housing estates § Road Development Authority (RDA) provide for new road network maps Note: Google Earth is a very important tool used to retrieve geographical information in order to update maps
Updating of Maps Updating of maps are done as follows: § Field visits carried out by officers of the unit § Digitize new morcellement and road maps obtained from MHL, NHDC and RDA
Tools Software Hardware Specification § Windows XP Professional § 4 Pentium IV PCs (2. 0+ MHz ) § Map. Info Professional 6. 5 § 3 PCs of 256 MB RAM and 1 PC of 512 MB RAM § Auto. CAD LT 2002 § 40 GB Hard Disk § 4 CD-ROM drive (52 x) § 2 Printers, 1 Photocopier and 1 Plancopier § 1 Plotter
Why Auto. CAD and Map. Info Auto. CAD § § § It is currently being used by MHL, NHDC and RDA, thus enabling trouble-free sharing of data among all collaborators It is a very powerful and precise CAD tool for drawing It can be easily imported from Map. Info Note: It has poor analytical possibilities v It is being used to produce EA maps Map. Info § § § It is a GIS software efficient in geographical analysis It is very user friendly It can import Auto. CAD drawings easily Note: It has poor drawing capabilities as compared to Auto. CAD v It is being used for analytical purposes
GEO-CODE The coding system of the EAs is of a hierarchical nature and comprise of six digits. § 1 st digit represents ISLAND § 2 nd digit represents DISTRICT § 3 rd & 4 th digits together represent TOWNS & WARDS (MCA) or VILLAGE COUNCIL AREAS (VCA) § Last 2 digits represent EA within the MCA or the VCA Example of an EA 131505
GEOGRAPHICAL AREA HIERARCHY STRUCTURE Republic of Mauritius Island of Mauritius (1) Island of Rodrigues (2) Island of Agalega (3) 9 Districts (Historical Boundaries) 5 MCAs 124 VCAs 14 Zones (Urban) (rural) (Rural) 20 Wards 2108 EAs 1364 EAs 93 EAs 1 EA
Types of Map Produced The unit produces 2 types of maps: 1. Field work mapping EA maps in digital format 2. Dissemination maps (Thematic Maps) published in : Population Distribution and Migration Analysis Report 2002 § Relative Development Index report 2002 § Census Atlas (not yet published) §
Needs and Use of Maps are needed: § Data Collection § Planning operations § Presentation and Analysis § To set up census and survey workloads § To estimate travel time and cost § To identify segments for sample surveys § To ensure complete coverage of an area without omission or duplication
CARTOGRAPHY UNIT Original map from MHL
CARTOGRAPHY UNIT Map updated by the CSO
EA Map
Location Map
Administrative Regions Map of Mauritius showing all the MVCAs* with their respective codes. *MVCAs – Municipal & Village council Areas
MASTER FRAME EA CODE PRIVATE HH U/R/S 20 02 Population PSU LOCALITY 111101 113 462 1 1006 Camp Chapelon 111102 4 18 1 1008 Bell Village 111103 36 127 1 1007 Plaine Lauzun 111104 86 365 1 1007 Plaine Lauzun 111105 107 372 1 1007 Plaine Lauzun 111106 140 570 1 1005 Camp Chapelon 111107 83 318 1 1006 Camp Chapelon 111108 89 368 1 1006 Camp Chapelon 111109 101 389 1 1002 G. R. N. W. , 111110 128 463 1 1004 G. R. N. W. 111111 67 242 1 1008 Cite Vallijee 111112 88 347 1 1009 Cite Vallijee 111113 69 251 1 1010 Cite Vallijee
Future Initiatives CSO § § § To use GIS in national surveys and censuses (sample design, workload, allocation, spatial analysis etc. . ) To adopt the web as part of the dissemination strategy through integration of interactive maps To enhance the quality and the presentation of the EA maps and thematic maps through the use of GIS To relate the socio demographic and economic characteristics to the housing and living conditions of the population by merging records of the Housing and Population Census enabling a more comprehensive analysis of the census data To capture census and survey through OCR/ICR. The latter is a proven technology that could make significant cost, timeliness and accuracy improvements in censuses and surveys
Future Government Projects In Collaboration with the International Services Landgate, Government of Western Australia To set up a CADASTRE OF THE ISLAND OF MAURUTIUS by THE ESTABLISHMENT OF A LAND ADMINISTRATION, VALUATION AND INFORMATION MANAGEMENT SYSTEM (LAVIMS) Main objectives : • Establish an efficient and cost-effective administration and information system that is an online and dynamic cadastre; and • Set up a general valuation roll of some 3000, 000 residential properties (land parcels) “Land Management Scrutiny Mission Final Report” published on the GOM / MHL website at: http: //www. gov. mu/portal/site/housing
Attributes of the cadastre and ownership databases and LIS • Every land parcel (LOT) on the island would be uniquely identified and digitally mapped • All cadastral lots would be held in a fully functional and secure digital cadastral database (DCDB) • The cadastre would have an overall geo-spatial accuracy, expressed in terms of WGS 84 and / or UTM as is planned for Mauritius • It would be a Geographic Information System (GIS) environment, capable of supporting migration to a web-enabled land information system (LIS); • It would be able to be spatially improved over time by introducing survey accurate and coordinated cadastral surveys into the cadastral system • Each land parcel would be linked to the owners deed for the parcel • Tracking of land transactions (sales, subdivisions, mortgaging (transcriptions) • Deeds lodgements and searching processes to be automated • Searching is able to be conducted on the Owners Name, Street, Deed number, State land identifier number, the Land Survey (LS) Number, and via a lot shown on the digital cadastral database
Change of Datum and Map Projection • The current coordinate system of Mauritius (geodetic datum) is Clarke 1880 Spheroid • The map projection is Lambert Conical Orthomorphic projection established in 1934 by Captain Sanseau • For better precision, the MHL has agreed to consider changing the datum to the World Geodetic System (WGS 84) and to move to Universal Transverse Mercator (UTM) map grid 84 Note: The Global Positioning System (GPS) uses the World Geodetic System 84 Problems With this change the current system will face technical problems. The existing data would need transformation before laying on the new coordinate system and map projection for Mauritius.
Shift due to differences between Clarke 80 and WGS 84 at a particular point Le Pouce (Clarke 80) 57. 5218 o E -20. 1951 o S 810 m dy = 337 m 67 o Le Pouce, Mauritius dx = 737 m Le Pouce (WGS 84) 57. 5289 o E -20. 1981 o S
Defining parameters of current map projection Ellipsoid : Clarke 1880 Map Projection : Lambert Conical Orthomorphic Latitude : 20 11’ 42. 25” South Longitude : 57 31’ 18. 58” East Use of measurement : metre Grid : Mauritius Origin : Le Pouce False Easting : 1 000 m Easting False Northing : 1 000 m Northing Scale factor at origin : 1. 000
Population Distribution Map Dot Map of Mauritius representing population distribution
Population Density Map Thematic Map of Mauritius representing population density per square km
Migration Streams Map of Mauritius showing net migration streams between districts for the past 5 years
Birth and Death Rates
Migration Streams Map of Mauritius showing net migration streams between districts for the past 5 years
THANK YOU Y. Buxsoo 11 October 2007
Migration Streams Map of Mauritius showing net migration streams between districts for the past 5 years
Migration Streams
Migration Streams
Migration Streams
Migration Streams