Any card has its own special language - specialconventional signs. Geography studies all these notations, classifies them, and also develops new symbols for designating certain objects, phenomena and processes. To have a general idea of conditional cartographic signs is useful to everyone. Such knowledge is not only interesting in itself, but it will certainly be useful to you in real life.
This article is devoted to conventional signs in geography, which are used in the compilation of topographic, contour, thematic maps and large-scale terrain plans.
Just as our speech consists of letters, wordsand sentences, and any card includes a set of certain notations. With their help, the topographers transfer one or another area to paper. Geographical conventions are a system of special graphic symbols used to denote specific objects, their properties and characteristics. This is a kind of "language" of the map, created artificially.
It is rather difficult to say exactly whenthe very first geographical maps. On all continents of the planet, archaeologists find ancient primitive drawings on rocks, bones or trees created by primitive people. So they portrayed the terrain in which they had to live, hunt and defend themselves from enemies.
Modern conventional symbols on geographic mapsreflect all the most important elements of the terrain: relief forms, rivers and lakes, fields and forests, populated areas, routes of communication, country borders, etc. The larger the scale of the image - the more objects you can map. For example, on a detailed plan of the area, as a rule, all wells and sources of drinking water are marked. At the same time, it is foolish and inappropriate to mark such objects on the map of the region or country.
Geography is a science that is extremely closely related to history. Let us delve into it, too, to find out what the cartographic images looked like centuries ago.
So, for ancient medieval maps, there wascharacterized by an artistic transfer of the terrain with a wide use of drawings as conventional signs. Geography at that time only began to develop as a scientific discipline, so when drawing cartographic images, the scale and outlines (boundaries) of the area objects were often distorted.
On the other hand, all drawings on old drawingsand the portals were individual and fully understood. But nowadays we have to connect memory in order to understand what those or other conventional signs mean on geographic maps.
Approximately from the second half of the XVIII century inEuropean cartography, there has been a trend towards a gradual transition from individual promising drawings to more concrete planned conventions. In parallel with this, there was a need for more accurate mapping of distances and areas on geographic maps.
Topographic maps and terrain plansdiffer quite large scale (from 1: 100000 and more). They are most often used in industry, agriculture, geological exploration, urban planning and tourism. Accordingly, the terrain on such maps should be displayed in the most detailed and detailed manner.
For this purpose, a special system was developedgraphic symbols. In geography, it is also often called the "legend of the map." For ease of reading and ease of memorization, many of these signs resemble the actual appearance of the terrain objects they represent (from above or from the side). This system of cartographic symbols is standardized and mandatory for all enterprises that produce large-scale topographic maps.
The topic "Conditional signs" is studied in the school coursegeography in the 6th grade. To check the level of learning this topic, students are often asked to write a small topographic story. Each of you probably wrote a similar "composition" in school. Proposals with conventional signs for geography look approximately the same as in the photo below:
All conventions in cartography are divided into four groups:
Let us consider in more detail each of these groups of signs.
In cartography, scales are those signs,which are used to fill any area objects. It can be a field, a forest or an orchard. Using these symbols on the map, you can determine not only the type and location of a particular object, but also its actual dimensions.
The boundaries of the area objects on the topographicmaps and terrain plans can be depicted as solid lines (black, blue, brown or pink), dotted or simple dotted lines. Examples of large-scale cartographic signs are shown in the figure below:
If the terrain object can not be represented inreal-scale plan or map, then in this case use off-scale conventional signs. We are talking about too small geographical objects. It can be, for example, a windmill, a sculptural monument, a rock-remains, a source or a well.
The exact location of such an object on the groundis determined from the main point of the symbol. For symmetric signs, this point is located in the center of the figure, for signs with a wide base in the middle of the base, and for signs having a right angle at the base of this angle.
It should be noted that objects expressed on mapsscale signs, serve as excellent landmarks. Examples of non-scale cartographic signs are shown in the figure below:
Sometimes in a separate group and socalled linear cartographic signs. It is not difficult to guess that with their help on plans and maps designate linearly extended objects - roads, borders of administrative units, railways, fords, etc. An interesting feature of linear designations: their length always corresponds to the scale of the map, but the width is significantly exaggerated.
Examples of linear cartographic symbols are shown in the figure below.
Perhaps the most informative is the groupexplanatory symbols. With their help indicate the additional characteristics of the depicted terrain objects. For example, a blue arrow in the riverbed indicates the direction of its flow, and the number of transverse lines on the railroad designation corresponds to the number of tracks.
On maps and plans, as a rule, subscribethe names of cities, towns, villages, mountain peaks, rivers and other geographical objects. Explanatory conditional signs can be numeric or alphabetic. The letters are most often presented in abbreviated form (for example, the ferry crossing is denoted by the abbreviation "par.").
A contour map is a special kind of geographic map intended for educational purposes. It contains only the grid and some elements of the geographic basis.
Set of contiguous contour map symbols by geographynot very wide. The very name of these maps is rather eloquent: for their compilation only contour designations of the boundaries of certain objects - countries, regions and regions are used. Sometimes they are also applied to rivers and large cities (in the form of dots). By and large, a contour map is a "mute" map, which is exactly designed to fill its surface with certain conventional signs.
Thematic maps are most often found inatlases on geography. The conditional signs of such maps are extremely diverse. They can be depicted in the form of a color background, areas or so-called isolines. Diagrams and cartograms are often used. In general, for each kind of thematic maps, there is a set of specific conventions.