Updating Topographic Maps at Scale 1:250000 for Libyan Territory Using Quantum GIS (QGIS) and Open Geospatial Data: Libya Topo-Project
تحديث
الخرائط الطبوغرافية بمقياس 1: 250000 للأراضي الليبية باستخدام
نظام المعلومات الجغرافية باستخدام برنامج (QGIS) والبيانات المكانية
مفتوحة المصدر: مشروع طبوغرافية ليبيا
Salah Hamad
Faculty of the Natural Resources and Environment Sciences, University of Omar Al Mukhtar, Al Baydah Libya.
Abstract
From the beginning of the twentieth century, topographic maps for the
Libyan state carried out by various compilers, where the first mapping
was carried out by the Italian Military Geographical Institute, the
Soviet Union Military, and the U.S. Army, followed by mapping carried
out by the Libyan state from the 1950s to the 2000s. Most of these maps
have not been digitized and updated using the techniques of geographic
information systems and remote sensing. This paper discusses on the
objectives, methodology and results of the Libya Topography Project,
“Libya Topo” for updating the previously compiled topographical map at
scale, 1:250000. Open spatial data from different platforms (OSM,
Logistics Cluster, Landsat 8 satellite imagery, and SRTM data, etc.).
Also, POIs extracted from previously compiled topographic and geological
maps. Spatial database for each UTM zone created to store the features
and raster. As for the cartographic style, the map layout adopted is the
style of the U.S. Defense Mapping Agency maps. The results of the
project are an update of 121 topographical map sheets using Quantum
(GIS), those will be freely available for the interested users on
request (e.g., environmentalists, academics, and university students,
etc.).
1 INTRODUCTION
Topographic maps are essential for geomorphological, regional and
local studies and defined as a detailed and precise two-dimensional
characterization of the land surface’s distinctive natural and
human-made features. They used for various applications such as urban
planning, resource management, surveying, and outdoor adventures like
hunting, fishing, and racing. The most distinguishing components of the
topographic maps are the elevation contours, which are imaginary lines
connecting similar elevation, and allow the representation of heights
for ridges, hills, and the mountains in addition to the steepness of the
slope in three dimensional. Also, the topographic maps contain many
symbologies to categorize both human-made and natural features such as
roads, buildings, quarries, lakes, streams (Pidwirny, 2009; Kennedy et
al., 1987; USGS, 2020; Brock et al., 2002). Topographic maps are the
essential types of maps and have passed through many stages of their
development and the means of production. Their importance is due to
their deepening in different fields, since they represent all the
phenomena on the earth’s surface, whether these are human-made or
natural. One of the first topographic mappings of large scale began when
John Wesley Powell persuaded the U.S. on 4-5 December 1884. Then
Congress permitted the U.S. Geological Survey (USGS) to enter systematic
mapping of U.S. topography. Twenty-five hundred years later, the
mapping techniques have currently moved forward from field surveys to
methods based on the computer through photogrammetry. Also,
topographical map scales and content have changed, and through that time
USGS, compiled maps in scales of (1:250,000 and 1:125,000). The scales
extended with time, and through 1894 maximum maps had been created at a
scale of 1:62,500. Where the characteristics are shown on the maps
included; state, county, town, or village civil divisions, in addition
to public utilities, such as tunnels, railroads, wagon roads, trails,
bridges, ferries, fords, dams, and canals (Usery et al., 2009; Usery et
al., 2018; Kind, 2014). Furthermore, the Soviet Union conducted during
the cold war, the most extensive cartographic project in the world
during the twentieth century that already covered foreign territories in
1938. Where, the global sheet of International Map of the World System
nomenclature adopted for the produced map sheets. The mapping initiative
was staggering in scope (Watt, 2005; Kent et al., 2019; Barney, 2014),
where the entire world mapped at scales: 1:1 million, 1:500,000 and
1:200,000: Most of Asia, Europe, northern Africa, and North America
mapped at scale 1:100,000. USSR and most of Europe, and the Far and
Near East at scale 1:50,000; USSR and Eastern Europe at scale
1:25,000. A quarter of the USSR at scale 1: 10,000. The Soviet Union
embarked secretly on the most extensive and systematic global mapping
project ever undertaken in the Cold War period. Several scales of
detailed topographical maps and plans of foreign territories (i.e.
1:5,000, 1:10,000, 1:15,000, 1:25,000, 1:50,000, 1:100,000, 1:200,000,
1:500,000 and 1:1,000,000) were produced by thousands of cartographers
working within the Union of Soviet Socialist Republics (USSR) in
accordance with standard specifications (Davis and Kent, 2017; Kent et
al., 2019). The Soviet Union maps became available to a broader audience
as the Soviet Union broke up. It started to appear in international map
dealer catalogs. Telecommunications and oil agencies have been eager
clients shopping for up Soviet maps of Central Asia, Africa, and other
parts of the developing world for which there were often used by aid
groups and scientists (Mustard, 2020; Kostelnick, 2018) Moreover,
topographical mapping represents a complex process that requires human
resources and time. Specialized manner improvement is likewise the
conventional approach for updating a country wide topographical map.
Many governmental mapping agencies and survey agencies have taken
several years to update topographical maps (Wagle and Acharya, 2020).
Topographic mapping has developed from field data collection based on
ground control surveying and field-sketching the terrain and planimetric
features by photogrammetry to digital collection geographic information
systems and remote sensing, which have brought considerable progress to
map design and production (Usery et al., 2018). The development has
reflected in the external and internal layout of the topographic map.
Presently many countries developed and updated their historical
topographical maps using modern data processing technologies inherent in
GIS geographic information systems and based on remote sensing data.
Moreover, platforms and map servers also offered many free spatial data,
not limited to significant landmarks such as highways, urban areas,
interest points, and local geographical names, where this has
facilitated the process of updating topographical maps. The U.S. Topo
series is an example of topographic mapping updates, where the USGS
topographic maps updated to make a new generation of American landscape
maps, where the topographic maps of the U.S. Topo created by the U.S.
National Geospatial Program of the U.S. Geological Survey (USGS). The
project began late 2009, and the word “U.S. Topo” explicitly refers to
quadrangle maps launched in 2009 and beyond. Those maps primarily based
totally at the acquainted 1947-1992 quadrangle maps of 7.5 minutes.
Still, they are mass-produced on a repeated cycle. U.S. from country
wide GIS databases, Topo-maps geographic information system: repackaging
data in standard map form, aiding non-specialist map users as well as
standard map applications (USGS, 2020).
In the early twentieth century, topographic maps accomplished for the
Libyan state by the various compiler and some of the produces maps is
illustrated, as shown in Table 1. During the Italian occupation period,
the Italian Military Geographical Institute carried out the first
completed extensive mapping covering all the Libyan territories that
followed in the 1940s by the Soviet Union mapping, and the U.S. military
mapping in the 1960s. Following the establishment of the Libyan state
in the 1950s, the government embarked on several topographical mapping
projects by the Libyan Surveying Authority.
Furthermore, the topographical mappings conducted by some Libyan institutions such as:
General water authority
Secretariat of agriculture and land reclamation
Libyan national army
Urban planning authority
These mapping were focused on specific regions or application;
geological research, hydrogeology, water resources, and agricultural
research. Also, most of these maps have not digitized and updated
according to modern techniques of GIS and RS since they do not include,
for example, the change in human-made features, urban areas, roads, and
electricity networks, etc. Nevertheless, some maps were produced during
the 2000s by some foreign geoinformation agencies, which are not
published publicly and are restricted to use by some institutions.
Since there are no new editions for the Libyan topographic maps and
have not subjected to accurate, comprehensive updates, it is also not in
proper format for geospatial software, so this limits the benefit to
users of these maps.
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