Symbols on a map or plan are a kind of their alphabet, by which they can be read, find out the nature of the terrain, the presence of certain objects, and evaluate the landscape. Usually, conventional signs on the map transmit common features with existing in reality geographic objects. The ability to decipher cartographic symbols is indispensable when performing hiking trips, especially to a distant and unfamiliar area.

All objects indicated on the plan can be measured on a map scale to represent their actual size. Thus, conventional signs on a topographic map are its "legend", their interpretation for the purpose of further orientation on the ground. Homogeneous objects are indicated by the same color or stroke.

All outlines of objects located on the map, according to the method of graphic representation, are divided into several types:

• Areal
• Linear
• Point

The first type is made up of objects that occupy large area on a topographic map, which are represented by areas enclosed in boundaries in accordance with the scale of the map. These are objects such as lakes, forests, swamps, fields.

Linear symbols are outlines in the form of lines, they can be seen at the scale of the map along the length of the object. These are rivers, railways or highways, power lines, glades, streams, etc.

Dotted outlines (off-scale) represent small objects that cannot be expressed at the scale of the map. These can be both individual cities and trees, wells, pipes and other small single objects.

Symbols are applied in order to have the fullest possible understanding of the indicated area, but this does not mean that absolutely all the smallest details of a real separate area or city are identified. The plan indicates only those objects that are of great importance for the national economy, the Ministry of Emergency Situations, as well as military personnel.

Types of conventional symbols on maps

Symbols used on military maps

To recognize the signs of a card, you need to be able to decipher them. Symbols are divided into scaled, off-scaled, and explanatory.

• Scale symbols indicate local features that can be expressed in size on the scale of a topographic map. Their graphic designation appears as a small dotted line or thin line. The area inside the border is filled with conventional icons that correspond to the presence of real objects in this area. The scale marks on a map or plan can be used to measure the area and dimensions of a real topographic object, as well as its outline.
• Out-of-scale legends indicate objects that cannot be displayed at the plan scale, the size of which cannot be judged. These are some separate buildings, wells, towers, pipes, kilometer posts and more. Out-of-scale designations do not indicate the dimensions of the object located on the plan, so it is difficult to determine the real width, length of a pipe, elevator or free-standing tree. The purpose of off-scale marking is to accurately indicate a specific object, which is always important when navigating when traveling in unfamiliar terrain. The exact indication of the location of the specified objects is carried out by the main point of the conventional sign: it can be the center or the lower middle point of the figure, the top right angle, bottom center of shape, legend axis.
• Explanatory signs serve to disclose information of large-scale and non-scale designations. They give additional characteristics to objects located on a plan or map, for example, indicating the direction of the river flow with arrows, designating forest species with special signs, carrying capacity of a bridge, the nature of the road surface, thickness and height of trees in the forest.

In addition, topographic plans are placed on themselves with other designations that serve as an additional characteristic for some of the indicated objects:

• Signatures

Some signatures are used in full, some are abbreviated. The names of settlements, the names of rivers, lakes are fully deciphered. Abbreviated labels are used to indicate more detailed characteristics of some objects.

• Numerical conventions

They are used to indicate the width and length of rivers, road and railways, transmission lines, point heights above sea level, fords depth, etc. The standard designation of the map scale is always the same and depends only on the size of this scale (for example, 1: 1000, 1: 100, 1: 25000, etc.).

In order to make it as easy as possible to navigate on a map or plan, the symbols are indicated in different colors. To distinguish even the smallest objects, more than twenty different shades are used, from intensely colored areas to less bright ones. To make the map easy to read, there is a table below it with a decryption color coding... So usually water bodies indicated in blue, light blue, turquoise; forest objects in green; the terrain is brown; city ​​quarters and small settlements - gray-olive; highways and highways - orange; state borders - in purple, neutral area - in black. Moreover, quarters with fire-resistant structures and structures are indicated in orange, and quarters with non-fire-resistant structures and improved dirt roads - yellow.

The unified system of symbols for maps and terrain plans is based on the following provisions:

• Each graphic sign always corresponds to a certain type or phenomenon.
• Each sign has its own clear pattern.
• If the map and plan differ in scale, objects will not differ in their designation. The only difference will be in their size.
• Drawings of real terrain objects usually indicate an associative connection with it, therefore they reproduce the profile or appearance of these objects.

To establish an associative connection between a sign and an object, there are 10 types of composition formation:

All objects on the ground, the situation and characteristic landforms are displayed on topographic plans with conventional symbols.

The main four types, into which they are subdivided:

1. Explanatory captions
2. Linear Symbols
3. Areal (contour)
4. Out-of-scope

Explanatory captions are used to indicate additional characteristics of the objects depicted: near the river they sign the speed of the current and its direction, near the bridge - the width, length and its carrying capacity, near the roads - the nature of the coverage and the width of the carriageway itself, etc.

Linear conventional signs (designations) are used to display linear objects: power lines, roads, product pipelines (oil, gas), communication lines, etc. The width shown on the topographic plan of linear objects is off-scale.

Contour or area conventional symbols represent those objects that can be displayed in accordance with the scale of the map and occupying a certain area... The contour is drawn with a thin solid line, dashed or depicted as a dotted line. The formed contour is filled with conventional symbols (meadow vegetation, arboreal, garden, vegetable garden, bushes, etc.).

To display objects that cannot be expressed on a map scale, out-of-scale conventional symbols are used, while the location of such an out-of-scale object is determined by its characteristic point. For example: the center of a geodetic point, the base of a kilometer pole, the centers of radio, TV towers, pipes of factories and plants.

In topography, the objects displayed are usually divided into eight main segments (classes):

1. Relief
2. Mathematical basis
3. Soils and vegetation
4. Hydrography
5. Road network
6. Industrial enterprises
7. Settlements,
8. Signatures and borders.

Collections of conventional symbols for maps and topographic plans of various scales are created in accordance with this division into objects. Approved by the state. bodies, they are the same for all topographic plans and are required when drawing any topographic surveys (topographic surveys).

Conventional signs that are most often found on topography:

Points of state geodetic network and points of concentration

- Land use and allotment boundaries with boundary marks at turning points

- Buildings. The numbers indicate the number of storeys. Explanatory signatures are given to indicate the fire resistance of the building (w - residential non-fire-resistant (wooden), n - non-residential non-fire-resistant, kn - non-residential stone, kzh - residential stone (usually brick), SMZ and SMN - mixed residential and mixed non-residential - wooden buildings with thin brick cladding or with floors built of different materials (the first floor is brick, the second is wooden)). A building under construction is shown with a dotted line.

- Slopes. They are used to display ravines, road embankments and other artificial and natural landforms with sharp drops heights

- Poles of power lines and communication lines. The legend follows the cross-sectional shape of the column. Round or square. Reinforced concrete pillars have a dot in the center of the symbol. One arrow in the direction of the electric wires - low-voltage, two - high-voltage (6 kV and above)

- Underground and overhead communications. Underground - dotted line, aboveground - solid. The letters indicate the type of communication. K - sewerage, G - gas, N - oil pipeline, V - water supply, T - heating main. Additional explanations are also given: The number of wires for cables, the pressure of the gas pipeline, the material of the pipes, their thickness, etc.

- Various areal objects with explanatory captions. Wasteland, arable land, construction site, etc.

- Railways

- Car roads. The letters indicate the coating material. A - asphalt, Щ - crushed stone, C - cement or concrete plates... On dirt roads, the material is not indicated, and one of the sides is shown with a dotted line.

- Wells and wells

- Bridges over rivers and streams

- Horizontals. Serve to display the terrain. Are the lines formed during the section earth surface parallel planes at equal intervals of height change.

- Elevations of the heights of the characteristic points of the terrain. Typically in the Baltic system of heights.

- Various woody vegetation. The predominant tree species, the average height of trees, their thickness and the distance between trees (density) are indicated

- Free standing trees

- Shrubs

- Various meadow vegetation

- Boggy with reed vegetation

- Fences. Fences are stone and reinforced concrete, wooden, picket fence, netting, etc.

Commonly used abbreviations in topography:

Buildings:

H - Non-residential building.

F - Residential.

KN - Stone non-residential

KZh - Stone residential

PAGE - Under construction

FUND. - Foundation

SMN - Mixed non-residential

SMZH - Mixed Residential

M. - Metallic

development - Destroyed (or fallen apart)

gar. - Garage

T. - Toilet

Communication lines:

3 ave. - Three wires on the power line pole

1kab. - One cable per pole

b / pr - without wires

tr. - Transformer

K - Sewerage

Cl. - Storm sewerage

T - Heating main

N - Oil pipeline

cab. - Cable

V - Communication lines. Number of cables in numbers, for example 4V - four cables

n.d. - Low pressure

s.d. - Medium pressure

v.d. - High pressure

Art. - Steel

cast iron. - Cast iron

bet. - concrete

Areal symbols:

bldg. - Construction site

og. - Vegetable garden

empty. - Wasteland

Roads:

A - Asphalt

Щ - Crushed stone

C - Cement, concrete slabs

D - Wood covering... Almost never occurs.

dor. zn. - Road sign

dor. decree. - Road sign

Water objects:

K - Well

well - Well

art well - artesian well

vdkch. - Water pumping station

bass. - Pool

vdr. - Reservoir

clay. - Clay

Symbols may differ on plans of different scales, therefore, to read the topographic plan, you must use the conventional symbols for the appropriate scale.

How to correctly read conventional signs on topographic surveys

Consider how to correctly understand what we see on topographic survey on a specific example and how they will help us .

Below is a topographic survey at a scale of 1: 500 of a private house with land plot and the surrounding area.

In the upper left corner we see an arrow, with the help of which it is clear how the topographic survey is oriented towards the north. On a topographic survey, this direction may not be indicated, since by default the plan should be oriented with the top to the north.

The nature of the relief in the surveyed area: the area is flat with a slight decrease to the south. The difference in elevation marks from north to south is approximately 1 meter. The height of the south point 155.71 meters, and the northernmost 156.88 meters. To display the relief, elevation marks were used that cover the entire topographic survey area and two contours. The upper one is thin with an elevation of 156.5 meters (not signed on the topographic survey) and thickened to the south with an elevation of 156 meters. At any point lying on the 156th horizontal, the mark will be exactly 156 meters above sea level.

On the topographic survey, four identical crosses are visible, located at equal distances in the form of a square. This is the coordinate grid. They are used to graphically determine the coordinates of any point on the survey.

Next, we will consistently describe what we see from north to south. In the upper part of the topographic plan there are two parallel dotted lines with the inscription "Valentinovskaya St." between them and two letters "A". This means that we see a street called Valentinovskaya, the carriageway of which is covered with asphalt, without a border (since these are dotted lines. Solid lines are drawn with the border, indicating the height of the border, or two marks are given: the top and bottom of the curb stone).

Let's describe the space between the road and the fence of the site:

1. A horizontal line runs along it. The relief lowers towards the site.
2. In the center of this part of the survey is concrete pillar power lines, from which cables with wires depart in the directions indicated by the arrows. Voltage of cables 0.4kv. There is also a street light on the pole.
3. To the left of the pillar, we see four broad-leaved trees (it can be oak, maple, linden, ash, etc.)
4. Below the post, parallel to the road with a branch towards the house, an underground gas pipeline is laid (yellow dotted line with the letter D). Pressure, material and pipe diameter are not indicated on the topographic survey. These characteristics are specified after agreement with the gas industry.
5. Two short parallel segments found in this area of ​​the survey are a conventional sign of herbaceous vegetation (forbs)

We pass to the site itself.

The facade of the site is fenced with a metal fence with a height of more than 1 meter with a gate and a wicket. The facade of the left (or right, if you look at the site from the street) is exactly the same. The facade of the right section is fenced wooden fence on stone, concrete or brick foundations.

Vegetation on the site: lawn grass with freestanding pines (4 pcs.) And fruit trees(also 4 pcs.).

On the site there is a concrete pole with a power cable from the pole on the street to the house on the site. An underground gas branch runs from the gas pipeline route to the house. Underground water supply is connected to the house from the side of the neighboring plot. The fencing of the western and southern parts of the site is made of a chain-link mesh, the eastern one is made of metal fence more than 1 meter high. In the southwestern part of the site, part of the fences of the neighboring areas made of a chain-link mesh and a solid wooden fence are visible.

Buildings on the site: In the upper (northern) part of the site there is a residential one-story wooden house... 8 is the house number on Valentinovskaya street. The floor mark in the house is 156.55 meters. In the eastern part of the house there is a terrace with a wooden closed porch... In the western part, on the adjacent plot, there is a ruined annex to the house. There is a well near the northeast corner of the house. In the southern part of the site there are three wooden non-residential buildings. One of them has a canopy on pillars.

Vegetation in neighboring areas: in the area located to the east - woody vegetation, to the west - herbaceous.

A residential one-storey wooden house is visible on the plot located to the south.

This way help to obtain a fairly large amount of information about the territory in which the topographic survey was carried out.

And finally: this is what this topographic survey looks like when applied to an aerial photograph:

Symbols there are contour, linear and off-scale.

• Contoured(areal) signs shown, for example, lakes;
• Linear signs - rivers, roads, canals.
• Out-of-scale signs on the plans they mark, for example, wells, springs, and on geographic maps ah - settlements, volcanoes, waterfalls.

Rice. 1. Examples of off-scale, linear and areal symbols

Rice. Basic conventional signs

Rice. Symbols of the area

Isolines

There is a separate category of conventional signs - isolines, that is, lines connecting points with the same values ​​of the depicted phenomena (Fig. 2). Lines of equal atmospheric pressure are called isobars, lines of equal air temperature - isotherms, lines of equal heights of the earth's surface - isogypsum or horizontals.

Rice. 2. Examples of contour lines

Mapping methods

To depict geographical phenomena on maps, various ways.By the way of habitats show areas where natural or social phenomena, such as animals, plants, some minerals, are distributed. Traffic signs used to show sea currents, winds, traffic flows. High-quality background show, for example, states on political map, a quantitative background - subdivision of the territory by any quantitative indicator (Fig. 3).

Rice. 3. Cartographic methods: a - way of areas; b - traffic signs; в - the method of high-quality background; d - quantitative background - point marks

To show the average magnitude of a phenomenon in any territory, it is most advisable to use the principle of equal intervals. One way to get an interval is to divide the difference between the largest and smallest values ​​by five. For example, if the largest indicator is 100, the smallest is 25, the difference between them is 75, its 1/5 -15, then the intervals will be: 25-40, 40-55, 55-70, 70-85 and 85-100 ... When showing these intervals on the map, more than light background or sparse shading represent less intensity of the phenomenon, darker tones and thick shading - more. This method of cartographic representation is called cartogram(fig. 4).

Rice. 4. Examples of cartograms and cartodiagrams

To the way cartodiagrams resort to show the total magnitude of a phenomenon in a territory, for example, electricity production, the number of students in schools, stocks fresh water, the degree of plowing of the land, etc. Schematic map they call a simplified map that does not have a degree network.

Relief image on plans and maps

On maps and plans, the relief is shown using contour lines and elevation marks.

Horizontals, as you already know, these are lines on a plan or map connecting points on the earth's surface that have the same height above sea level (absolute height) or above the level taken as a reference point (relative height).

Rice. 5. The image of the relief by horizontals

In order to depict a hill on a plan, you need to define it relative height, which shows the vertical distance one point of the earth's surface is higher than another (Fig. 7).

Rice. 6. Image of a hill on a plane

Rice. 7. Determination of the relative height

The relative height can be determined with a level. Level(from fr. niveau- level, level) - a device for determining the height difference between several points. The device, usually mounted on a tripod (tripod), is equipped with a telescope adapted to rotation in the horizontal plane and a sensitive level.

Conduct leveling the hill - this means making measurements of its western, southern, eastern and northern slopes from the bottom to the top with the help of a level and driving in the pegs in those places where the level was installed (Fig. 8). Thus, four pegs will be driven in at the foot of the hill, four - at a height of 1 m from the ground if the level is 1 m, etc. The last peg is driven in at the top of the hill. After that, the position of all the pegs is plotted on the terrain plan and first all points with a relative height of 1 m are connected with a smooth line, then - 2 m, etc.

Rice. 8. Not lighting the hill

Please note: if the slope is steep, the horizontal lines on the plan will be located close to each other, but if the slope is flat, they will be far from each other.

Small lines drawn perpendicular to the contours are bergstrokes. They show in which direction the slope is going down.

The horizontals on the plans depict not only heights, but also depressions. In this case, the bergstriches are turned into inner side(fig. 9).

Rice. 9. Image by contours of various forms of relief

Steep slopes of cliffs or ravines on maps are denoted by small teeth.

The height of a point above the mean sea level is called absolute height. In Russia, all absolute heights are calculated from the level of the Baltic Sea. Thus, the territory of St. Petersburg is above the water level in the Baltic Sea by an average of 3 m, the territory of Moscow is 120 m, and the city of Astrakhan is 26 m below this level. The elevation marks on geographical maps indicate the absolute heights of points.

On a physical map, the relief is depicted using layer-by-layer coloring, that is, with a color of varying intensity. For example, areas with a height from 0 to 200 m are painted over in green color... At the bottom of the map there is a table from which you can see which color corresponds to which height. This table is called scale of heights.

Cartography as a science dates back to the Bronze Age. Archaeological excavations have shown that the oldest samples were created in Egypt, ancient babylon, Asia Minor (modern Turkey), the Marshall Islands and Italy. Without a schematic outline of the terrain, accurate movement and implementation is impossible military tactics... Despite completely different ideas about the shape of the planet, the inhabitants Of the ancient world, The Middle Ages, the Renaissance, the New Age and the present, they tried to record as accurately as possible all the features of the landscape. Ancient people made many geographical inaccuracies in cartography, and the creation of diagrams could be equated with art - they were performed by real masters and supplemented with many artistic elements. For example, cities were depicted in the form of towers of castles with family coats of arms, forests were represented by several species of trees, commercial ports were denoted by the type of ships popular in the region (Figure 1).

Figure 1. Maps used before the last century

More similar to modern samples appeared only after the 18th century, when mankind received a complete picture of the geography of the planet, the location of all rivers, seas, oceans.

However, the most accurate plans became available by the middle of the twentieth century.

In everyday life, knowing what the symbols of geographical maps mean will help you quickly get to any destination. In the wilderness and survival, getting lost in the forest, but having a map with you, you can save your life and get out easily. Despite the popularity of GPS navigators, electronic equipment can always fail, incorrectly determine the coordinates or discharge. Paper counterparts are at hand and come to the rescue in any situation. They are easy to use, not only to find out where you are in wilderness or inhabited areas, but also to plot shorter road routes. Without the use of diagrams, it is difficult to imagine the work of the military, foresters, fishermen, geological engineers and builders. What are the types of symbols on maps and how to identify them exact value, we will consider further.

Symbols of geographic maps

Symbols on the map are presented in the form of simplified graphic symbols that indicate landscape objects, for example, mountain ranges, lakes, forest plantations, paths, highways, public and residential buildings, boundaries between settlements. The icons differ depending on the type of application. For example, for urban plans they will be the same, and for suburban plans they will be completely different.

Figure 2. Main groups of characters

The following groups of characters are distinguished (Figure 2):

1. Scientific or reference. Includes soil types, landscape and soil details, fossils located in the area, types of water bodies and trees, common animals, birds and fish, buildings, municipal and socio-cultural monuments, transport interchanges and much more. The purpose of such schemes is a detailed display of all important features landscape for accurate orientation. Also used for informational purposes;
2. Educational. Developed for teaching preschool and school children. Often interactive and intuitive;
3. Tourist. It is impossible to imagine the luggage of any traveler without them. Contains precise terrain details. However, more attention is paid to paths in forests and mountains, crossings over rough or wetlands. This group also includes urban variants that clearly explain the new city. With their help, it is easy to visit all excursion places without getting lost in the interweaving of residential quarters and numerous streets.

The newer the scheme, the more it corresponds to the real location of all objects. Often presented in color for easier orientation.

Figure 3. An example of a legend for different maps

The structure of all geographical maps - both outdated and modern - is divided into two main parts:

• A schematically depicted landscape. The colors evoke the correct associations with the real components of the relief: forest plantations are green, reservoirs are blue or blue, hills are brown, motorways are red or orange, and railway tracks are black. Sometimes details are given, such as the material of the bridge or the type of forest. However, on each plan many more signs are displayed, many of them may seem incomprehensible at first glance;
• Legend (Figure 3). Legend refers to the explanations for each individual scheme. There is no general standardization in cartography, but the decoding of designations and content must be present without fail, otherwise it is considered invalid. You can find the legend in the free fields. Sometimes a separate place is allocated for it. Even if you have forgotten what the icons on the plan mean, referring to the legend, you can intuitively figure it out.

Contrary to the prevailing stereotypes, you do not need to have specialized skills to read a geographic map, and even a schoolchild can cope with this task. Faced with new scheme, it is enough to get acquainted with the legend and begin to orientate.

Types of conventional symbols on maps

Symbols of geographical maps are necessary for displaying schematic objects, their features and characteristics on the terrain plan. They are divided into three varieties, which are determined by the scale: linear, areal and point. Each of them includes objects similar in their features: industrial buildings and administrative facilities (bridges, railway crossings, borders between regions and countries) or details of a natural landscape. Each group is identified with a simple and easy to remember icon. For example, coniferous forests are represented by the schematic pine symbol (Figure 4). It reliably displays the type of object and is universal for most terrain plans, which will provide a convenient and instant orientation in any conditions.

Figure 4. Types of signs on maps

The main requirements for the icons, which can be used to select a suitable geographic map:

1. Readability and recognizability;
2. Lack of congestion of elements;
3. Ease of memorization;
4. Compactness and reliability.

We will consider further what topographic map symbols include.

Linear signs

Linear conventional signs on the map depict objects with a certain length (Figure 5).

Among them:

1. Roads (highways, highways, highways, paths). They are divided into unpaved and asphalt ones. Modern and roadworthy highlighted in orange. Gray or black represent non-paved road sections or paths;
2. Railway and tram tracks. They are divided according to the number of tracks (one or several pairs of rails), width (narrow or standard), as well as general condition (working, closed and in construction mode). They are indicated by a horizontal line on which perpendicular lines are drawn in the order: one track - one line. A rectangle is drawn on the line, which indicates the station building or platform;
3. Bridges. They differ depending on the material (reinforced concrete, wooden, stone and others), the number of tiers, dynamics (solid, sliding or lifting). Pontoon (floating) are designated by separate symbols;
4. Gas or oil pipelines;
5. Power lines;
6. Cellular or radio communication towers;
7. Rivers of any length or streams, canals;
8. Any fences or walls
9. Borders between settlements and countries.

Figure 5. Example of linear signs

They are represented by colored thin, bold and bold lines (straight, curves). It should be noted that only their length in millimeters with conversion to scale is accurate.

Geographic maps do not have the correct designation for the width of linear characters.

The exaggerated width makes reading easier. This group also includes isolines (isohypses) necessary for the volumetric designation of the forms and features of the territory.

Areal signs

Areal (they are also large-scale) conventional signs on the terrain map are needed to correctly convey the shape and shape, relief, size and location of large geographic sites(Figure 6). Also called "contour". These include both individual sites localities and entire cities. They have a reliable length and width in a two-dimensional plane, presented on a reduced scale (for example, 1: 10000) and as close to reality as possible. Their structure is divided into an outline and a colored background, hatching or a grid of identical symbols that indicate the properties of an object.