A reduced image depicting all or part of the Earth’s surface on a plane made on the basis of strict mathematical principles is a geographic map. There are also astronomical maps. These are maps of the celestial vault, or the moon, based on similar mapping methods. Some researchers classify astronomical maps as geographic thematic maps.
Since modern geographic maps show a huge variety in terms of content, size, purpose, etc. there is a need to classify them. The simplest division of maps is based on their scale. They can also be classified by content, purpose, or use. Sometimes it is also taken into account the area that the map covers, the number of colors from which it is made, while less often the time, and the place of issue is selected as a criterion for classification.Such criteria were recognized in the past. With regard to the content, mapscan be divided into general geographic, and thematic.
General geographic maps show the full geographical and cartographic characteristics of a territory, and mainly highlight those elements of the Earth’s surface that have clear geometric outlines. On such maps, sea coasts, rivers, lakes, glaciers, relief of land and sea bottoms, sands, mudflats, forests, settlement system, transportation routes, political and administrative borders, etc. are marked. General geographic maps do not include those elements that cannot be seen directly on the Earth’s surface, but which can be cartographed by special methods and so, for example, data on precipitation, rock bed structure, industrial production, etc. The general character of these maps is emphasized by including all elements of physical geography as well as socio-economic geography as evenly as possible.
General geographic maps are constructed on the basis of a direct photograph of the area. This photo, taken at a sufficiently large scale, contains all the elements that can be measured and then plotted on the map. General geographic maps of smaller areas are made intimately with appropriate generalization. Among the general geographic maps can be distinguished a group of those that have in their content a predominance of physical and geographical elements, that is, landforms, water relations, vegetation, etc. Such maps are called physical maps. Opposed to them are maps whose content is dominated by socio-geographical and, above all, political, and communication elements. Such maps are called economic, socio-economic, or political maps.
Thematic maps, on the other hand, are cartographic works that, unlike general geographic maps, lack a complete characterization of a given territory. These maps give a complete depiction of one element of a general geographic map, such as administrative or socio-economic division, or climatic or soil relations. In maps of this type, the general geographic content retains a special importance as a primer. When depicting a certain phenomenon on a thematic map, it is necessary to preserve for orientation the main geographic elements of the Earth’s surface such as the outline of the coastline, river network, elevation points, etc. This basic outline of the content presented on thematic maps is the geographic underlay.
Among thematic maps, one can separate maps that depict elements, or natural phenomena, or those that present socio-economic phenomena. Moving on to maps of natural phenomena, one can single out geologic maps, which are made on the basis of geologic photographs developed in the field. These photos are then superimposed on a geographic base generalized accordingly. Geological maps show the distribution of individual geological formations, or the areas of occurrence of one formation.
Geologic maps are difficult to produce because they require the use of a considerable amount of color. The way geological formations are marked on the maps is arbitrary, however, certain colors are used to mark geological periods. In addition to colors, geologic maps also contain a number of conventional signs (e.g., the course of rock layers, faults, etc.). As well as letter abbreviations. Among geological maps, hydrogeological maps, which show the distribution of groundwater in the various geological levels, should also be specified. Soil maps, like geologic maps, are created on the basis of special field surveys (field mapping), the results of which are plotted on geographic bases. These maps, too, contain a number of colors, signs and letter abbreviations. Geomorphological maps, on the other hand, contain geomorphological forms of their assemblages and types found on the Earth’s surface. A separate group consists of climatic and meteorological maps.
Since meteorological phenomena are variable in time and space to illustrate them, the use of maps is ideal. The simplest type of climate maps are those that reflect the instantaneous state of the atmosphere in a given area called synoptic maps. Maps of this type are currently very important for weather prediction. A characteristic feature of meteorological maps is the representation of atmospheric phenomena on them by isarithmic methods. Isarithms are lines connecting points with equal values of a given phenomenon. Meteorological maps often carry isochrones, i.e. lines of simultaneous movement of a given phenomenon. Microclimatic maps reflecting atmospheric relations in the immediate vicinity of the Earth’s surface are also encountered. Physical geographic thematic maps also include hydrographic maps expressing water relations, and maps of vegetation lands, giving a picture of floristic regions. These maps often use surface methods of linear ranges, and point and area determinations. There are also maps that reflect the distribution of individual animal species, or entire faunal units. These are zoogeographic maps.
Maps of social and economic phenomena are numerous, as they play an important role in various areas of life. Among them can be distinguished population, economic, political, and historical maps. In the group of population maps, there are distinguished maps of the distribution of nationalities (ethnographic), demographic maps, showing the spatial variation of demographic processes such as age structure, gender structure, occupational structure, etc. Maps showing population density are very widely used. Of the cartographic methods of presenting information on demographic maps, the surface, cartodiagram, cartogram, point, and range methods are used. These methods are discussed in the next chapter. Economic maps show the distribution, characteristics, and interrelationships of economic phenomena. We can distinguish maps that present separate branches of the economy, so maps of industry, energy, transportation, agricultural economy, and comprehensive maps that give a combined picture of economic phenomena, as well as the economic characteristics of a region. Energy maps give the distribution of raw materials of energy resources (peat, coal, oil), and energy-generating facilities.
Agricultural maps show the distribution of agricultural production, its transformation, and the degree of intensification. On this type of maps we can also find the distribution of production of various agricultural enterprises and facilities, their size, and production. Transportation maps reflect economic phenomena related to transportation and the economic importance of various types of transportation routes. Maps of this type usually depict the nature and main directions of transportation of a particular commodity, as well as the main transportation routes, as well as transshipment points and frequency of transportation. Another group is made up of political maps, which usually contain the most accurate possible distribution and size classification of localities, along with a reasonably detailed administrative division of the areas they depict. These maps render transportation routes in great detail. A separate group is also formed by historical maps, which depict phenomena of a social-economic, and political nature in different historical periods. Mostly these are general maps, collected in historical atlases, or wall maps.
You can also differentiate between nautical maps, which are mainly used to designate sea routes for ships. These maps are usually characterized by a small number of colors, the Merkator fidelity grid used, and a significant number of depth points distributed throughout the water surface, especially in coastal areas. Nautical charts are divided into a number of types depending on their intended use. The most numerous group are navigational charts constructed at various scales. They contain both depth points and isobaths. For easier orientation, these maps detail characteristic parts of the shore, or individual objects visible from the ship. In addition to nautical maps, maps, road maps, and railroad maps are also used for communication purposes. The tradition of road maps dates back to the 18th century, when these maps were used for postal purposes.
Nowadays, the most important role in this group is played by land road maps for the use of automobile communication. Railroad maps, on the other hand, are less frequently published. They are mostly issued for official purposes for railroad employees. A very important role in common use, however, is played by tourist maps. In addition to the common content of the map, the area contains a number of objects that are tourist attractions, such as natural elements, and cultural features. Tourist maps also depict in detail the tourist infrastructure of an area and thus accommodation centers, food and beverage outlets, hiking trails, etc. Tourist elements are usually highlighted in color on maps of this type. Walking paths are printed in the color with which they are marked in the field. Based on scale, or size, and the degree of accuracy, maps can be divided into three groups:
Overview maps
These are otherwise small-scale maps – these maps are constructed at a scale of 1: 1000000, or smaller (e.g.1:5000000, 1:20000000). They cover large areas (e.g., continents). The degree of generalization of overview maps depends on their purpose. E.g., on wall maps it is greater than on maps intended for individual use and made at the same scale. On overview maps, equal spacing between horizons is not used to represent relief, but horizons are chosen to characterize the main terrain irregularities. It is common to use coloring of the areas located between the different horizons according to an adopted color scale, which is called the hypsometric scale.
Overview and topographic maps
These maps are otherwise known as medium-scale maps. They are presented
inthey scales from 1:1000000 to 1:200000. overview and topographic maps are constructed after the content of the topographic map is generalized. (only the more important content remains on them). The described maps have features of both overview maps and topographic maps Linear widths are not measured on maps of this type.
Topographical maps
Topographic maps are otherwise large-scale maps. They are made at scales larger than 1:200,000.These maps give the most complete picture of the Earth’s surface. The relief of the land and the situational drawing are rendered here in as much detail as possible. The emergence of topographic maps is associated with the advancement of geodetic knowledge, and the development of new methods of measurement and drafting. The first topographic maps were created in the middle of the 18th century. Prior to that, maps were very general and usually depicted entire countries, less often individual provinces or areas. Topographic maps at scales larger than 1:100,000 are generally the direct result of topographic photography in the field.
A topographic map made at a large scale should be legible and allow easy orientation. The accuracy of the representation of topographic map elements should correspond to its scale. The content of a topographic map is rendered as a reduced vertical projection of certain objects. The representation of selected objects according to scale could lead to the reproduction of important elements of an area in a very negligible size. For example, highways would not differ from equally wide roads of lesser importance. Important landmarks on the map would not mark themselves properly on the map and would be difficult to find.
Therefore, it is necessary to adopt certain signatures or conventional marks aimed at highlighting certain important elements. The content of a topographic map is divided into terrain and situational drawing. The situational drawing consists of objects encountered on the surface of the Earth and therefore: points of the geodetic warp, hydrographic network with representation of the coastline, lakes rivers, springs, wells, river channels, etc., elements of vegetation cover, physiographic elements (sands, glaciers, deserts, etc.), localities depicted at larger scales with accuracy to individual buildings, industrial and agricultural facilities, elements of social infrastructure (e.g., schools), above-ground lines of communication with their classification. In addition, topographic maps include landmarks (towers, churches, windmills, etc.).
Terrain on topographic maps should be understood as a set of elements relating to the vertical relief of the Earth’s surface. It is currently presented only in the form of a level drawing. For greater clarity, topographic maps are printed in color. The most common colors are brown for relief, green for forests and grasslands, and blue for water. Individual sheets of topographic maps are labeled with a name (usually the most important locality within the map), and an emblem, which indicates the location of a given sheet of the map in the general numbering system. The geographic location on topographic maps is indicated by describing the meridians and parallels. The linear scale and numerical scale are usually placed at the bottom of the map. Topographic maps also have a kilometer grid, which gives the ability to determine in a short time, and with a high degree of accuracy, the location of points on the map.
