The world of biology and geography. Photogrammetric processing of aerial survey data

Relief is the main factor in the redistribution of heat and moisture on the Earth's surface. The biota adapts to the lithogenic base, and, first of all, to the relief, and the nature of soil-forming processes often directly depends on it. Therefore, the boundaries of the PTC very often coincide with the boundaries of forms or elements of relief forms. Hence the special interest in analyzing topographic maps in preparation for landscape mapping.

The basis for drawing up a preliminary landscape map is the translation of the image of the relief of the Earth's surface using contour lines, as is done on topographic maps, into another model - into an image of the relief with contours, characteristic of most industrial maps. Then these contours are filled with content and a legend is drawn up. The contours emerge

They are determined, first of all, on a topographic basis, as well as on aerial and satellite photographs and adjusted according to industry maps. Based on these same materials, their content is revealed, as far as possible in laboratory conditions.

Working with topographic maps. The depiction of relief by contour lines, used on topographic maps, is a wonderful way of conveying volumes on a plane, a kind of continuous image, while a map of relief forms in contours is a purely planar discrete image. It is more difficult to assess the dynamics, especially of gravitational (erosion, runoff) and other processes. Ideally, on a landscape map it would be better to combine both methods of drawing the relief, but this is difficult to achieve for technical reasons and, above all, because the landscape map itself often turns out to be very busy and difficult to read.

It is very useful before starting to work with topographic maps to view the “Album of Relief Images on Topographic Maps” (1968), where each fragment of the map is accompanied by a stereo pair of aerial photographs and text. It is noteworthy that from a topographic map in combination with aerial photographs, not only the structure of the surface, but also the composition of rocks, the genesis of sediments and landforms are often clearly readable.

Summary method of contour image of the relief. First, a river and erosion network is identified on a topographic basis: river valleys, ravines, gullies, and hollows are outlined. Then the remaining sections of the interfluves are divided according to the degree of steepness into contours with approximately the same concentration of contours.

As practice shows, the most difficult step is the first one: “break away from the horizontal,” that is, understand that the contour of the erosion form always intersects the horizontals, and does not go along them.

The following presentation is the key to understanding the basics of landscape mapping techniques. Therefore, it is recommended that, after reading it, you try to do similar work yourself, if necessary, returning to study the text and illustrations. It is useful to have several versions of educational cards on thick paper, where a soft pencil could be used to try out different variants decisions. This text must be worked out thoroughly, including all captions for the figures.

It is most convenient to start learning to draw contours, firstly, on maps of a large scale of 1: 10,000 (or larger), in extreme cases - at 1:25,000 and, secondly, on maps depicting erosional relief, where the beam network and pronounced slopes.

For training sessions usually several versions of blank maps are prepared, where all topographic load is removed, except for relief

fa in horizontals. Thus, all factors except erosion are removed. This is done to quickly acquire formal drawing skills first without the involvement of other industry maps and aerial photographs. Learning to “feel the terrain” is useful for geographers of all specialties.

Having “solved” such a problem on several fragments of topographic maps, i.e. Having “caught” and delineated all the erosion forms and divided the remaining territory according to the degree of steepness, you can begin to use aerial photographs and various industry materials, try to characterize each resulting section, and reveal its content. From this moment the process of analysis and synthesis begins - the art of optimally translating all one’s knowledge into a cartographic model. Most likely, the initial drawing of the contours will have to be slightly changed.

Formal drawing of landscape contours is not that difficult (once the initial skill is acquired) and can be automated. However, in our opinion, only maps of the largest scale provide a more or less real image of the relief and, accordingly, the identified contours of the PTC. On maps of medium and small scales, generalization of the topographic basis and drawing the contours of natural components or complexes on it leads to a distortion of both the nature of the contours themselves and the ratio of areas various types mapped natural objects.

We recommend that you refer to the developments of A. V. Gedymin (1992). Using examples of erosionally dissected landscapes of the forest-steppe and steppe of the Russian Plain, he briefly and clearly outlined the essence of the method of drawing the contours of large-scale soil maps along the relief in horizontal lines, which is also acceptable for drawing up preliminary; detailed landscape maps.

We present his drawings in horizontals: slopes of various shapes and steepness, elements of river valleys, erosion forms, etc. (Fig. 16, 17, 18, 19), accompanied by some explanations.

On the fragment A(Fig. 16) based on the density of contours, it is possible to distinguish three contours of sub-urochisms of slopes of different steepness; on the fragment B also three sub-tracts and one or two simple tracts of hollows. Fragment IN It is uniform in steepness and is a section of a tract without sub-urochishches. In Fig. 17 Gedymin gives examples of drawing relief elements in contours with a brief litho-logo-morphological characteristics and an indication of the main features of soil formation conditions (moistening, processes of gleying, washout, alluvium). In Fig. 19, the contours of the bottoms of the erosion beam network are clearly visible, which in Fig. 20 is given under number 8. The bottoms of valleys of streams and small rivers may have a similar pattern at a smaller mapping scale.

In Fig. 20 it is clearly visible that the contour of the bottom cuts the horizontals at the point of their sharp bend, in the so-called lock, and its width does not exceed the width of the lock. Where two or more beams meet, their bottoms are usually joined at an acute angle, although there may be enough space between the horizontals to draw a right or obtuse angle. This would be wrong, since when two streams of water merge, they usually form an “arrow” here, as when one river flows into another.

In the upper reaches, where the horizontal turns become smooth, the bottom and beam end.

In Fig. 20 the summit catchment is drawn (9), the contour of which also cuts the horizontal lines at the place of their smooth bend. Deep into the watershed surface, the contour is drawn until the bend of the horizontal lines is traced or just above the last bend; The lower part of the slope of the interfluve adjacent to the drainage basin is moistened more than its convex top part, and according to the conditions of soil formation, it is close to the conditions of the top catchment.

Often the summit catchment areas of two gullies merge into each other.
with each other, forming wide saddles (10 in Fig. 20) with weakened
no drainage in its middle part. If you look closely
Xia, then you can see that the boundaries of the slopes of the beams (4, 5 in Fig. 20),
slopes of the interfluve surface (3 in Fig. 20) also flogged
horizontally, drawing contours, if not equal
noah, then close to the steepness. ____________

I tilt. In this case, the values ​​calculated for each angle of inclination? The measurements must be converted to millimeters and to the scale of the map being used.

On the left side of Fig. Figure 21 shows a segment equal to the location of horizontal lines on a slope of a given steepness. Using this segment, drawn on tracing paper, we found those places where the distance | between adjacent horizontal lines is equal to the given slope and, therefore, the slope is equal to the given one.

Where the distance between the horizontal lines is equal to the laying if, I drawn and constructed in advance for given angle tilt-I on the surface, points A, B and C were placed on the map, and the desired line was drawn through I, above which the surface has less slope angles, and below it more than the given one. When drawing a line through these points, it was taken into account that the distance between adjacent horizontal lines (layout) changes gradually, and | This means that the steepness of the slope gradually changes. The entire strip between I adjacent horizontal lines, located below point C, is less (narrower) than the level corresponding to the given steepness. Therefore, the leftmost part of the line is drawn as a bend in the steepness - the edge of the slope (see also Fig. 22 and 23).

In practice, you always want to draw the edge and bottom of a slope along the upper and lower horizontal lines of a thick “bundle.” But this tendency must be overcome. Firstly, because the edge and

The surface along this line (and not above or below it) is very small. This means that the boundary should be drawn higher or lower. The second difficulty arises in the place where the horizontal lines begin to diverge (thin out) and they have to be crossed. Both cases are considered in Fig. 22, 23.

In Fig. Figure 22 shows a somewhat schematic image of the relief contours of a section of the slope of a river valley in the form of a “pack” (or “bundle”) of contours located close to each other. In the western part of the slope these are horizontal lines 3, 4, 5, 6, 7, 8, and in the eastern part - 2, 3, 4, 5, 6, 7. To the north, the valley slope clearly turns into a slightly inclined and fairly flat watershed surface, and towards south into the slightly inclined surface of the terrace. The upper horizontal line 8 of the western part of the slope, having made a slight turn approximately in the middle of the section, then follows the watershed surface, and in the eastern part of the slope its upper horizontal line becomes the adjacent underlying horizontal line 7. In this case, the horizontal line 8, before reaching the watershed surface, makes a turn exactly at edge of the slope (point A). Around the same average

In the lower part of the site, there is a change in the lower horizontal line of the slope: instead of horizontal line 3 in the western part of the slope, in the lower eastern part there becomes horizontal line 2, which previously ran along the surface of the terrace. All this suggests that the watershed surface, the slope, and the surface the terraces, i.e. the entire depicted area, gradually decrease from west to east, which, by the way, corresponds to the same direction of flow of the river located to the south of the area depicted in the figure.

In three places in Fig. 22, curved lines CE, KL and OP are drawn, intersecting the horizontal lines at approximately right angles. In this case, line KL is drawn through point A of horizontal line 8, i.e. where it intersects the edge of the slope. Three profiles are constructed along these lines, shown in Fig. 23. It also conventionally shows segments of horizontal lines (under the profiles) and lines of the corresponding horizontal planes. Places of change in steepness, i.e., places of rotation of the profile lines themselves, were constructed approximately. In these places, with some approximation, the edge points of the slope were found (on profiles CE and OP), as well as the base (on all three profiles). These points were transferred to Fig. 22 and through them and point A the lines of the edge and sole were drawn. Having some experience in work, the lines of the edge and bottom of the slope can be drawn directly along the pattern of contours (but, as shown, not along the contours themselves) without first constructing profiles.

It is obvious that the lines of the edge and the bottom of the slope obtained by graphic construction are still somewhat approximate. However, drawing boundaries between different soils and PTC directly horizontally distorts the actual position of these boundaries. And here the question arises: how to draw the line of such a boundary in the place where one upper horizontal line of the slope, moving away from it onto the watershed surface, is replaced by an adjacent underlying horizontal line (as in Fig. 22 in the area near point A)? A similar question is inevitable when changing the lower horizontal line of the slope. The horizontal when leaving or entering a slope does not always make such a clear turn as at point A in Fig. 22. For example, turning the horizontal 2 when it enters the slope from the surface of the terrace does not give such a clear picture, and the point of the bottom on the horizontal in this case is determined less accurately.

The influence of relief on the formation of PTC, as mentioned above, lies primarily in the redistribution of moisture and heat.

Therefore, if, when dividing slopes into parts according to the steepness of the surface, there are cases when some significant section of the slope could be distinguished by its steepness into a certain category, but in its middle part there is a small strip of a gentler slope, it is not advisable to single out this strip separately, so how moisture flowing down the surface will not have time

Significantly reduce the speed of movement and it will seem to jump through this strip. It is also inappropriate to single out a separate small strip of a slope with a greater steepness, which happens to be inside a significant part of it, allocated to a category with a lower steepness.

Exposure differences in heat supply on steep slopes are more pronounced than on gentle ones; on southern (and southwestern) and northern (and northeastern) slopes they are better than on western and eastern ones. Therefore, when compiling a preliminary NTC map, the steep slopes of northern and southern exposures should be given different numbers. Convex slopes, both on the profile and in the plan, differ from concave slopes in moisture content, and this must also be taken into account when drawing the contours of the PTC.

We considered only specific examples of identifying the contours of forms and relief elements in conditions of erosion plains middle zone Russian Plain with large-scale mapping. In other physical and geographical conditions, new questions will arise. For example, in conditions of a hilly-ridge moraine relief alternating with water-glacial surfaces, where the erosion network may be poorly developed, for the first, most general delimitation of the territory into different natural complexes, A. A. Vidina (1974) recommends coloring the map in horizontal lines different altitude levels. Indeed, this technique makes it possible to understand without much difficulty the complex “interweaving” of moraine and water-glacial formations. On moraine hills, peak surfaces may appear, gently sloping or with small hills, and on aquaglacial plains terrace-like surfaces of different levels will be visible. However, this technique of tiered coloring along horizontal lines can also be useful in erosion-dissected areas. In both cases, this makes it possible to identify the layering of the NTC, in particular the slope microzonation.

The rank of the PTC, allocated to an independent circuit, also depends on the scale of the map. For example, on a map at a scale of 1: 10,000 in the floodplain of a more or less significant river, the ribbed relief along the horizontal lines is clearly visible, and each mane and inter-ridge depression (tracts) can be identified with a contour. On maps at a scale of 1:25,000 this is no longer always possible and often the entire section of the ruffed floodplain is highlighted, i.e. a whole set of interconnected tracts. On a map of a scale of 1: 200,000, even the entire floodplain is almost impossible to trace along the contours, since the cross-section of the contours is 20 m, and the relative elevation of the terraces above the floodplain can be 5-10 m.

In this case, other indirect signs that can be read from a topographic map help, for example, the border of meadow and arable land (although the floodplain may also be plowed and the terrace meadow). Sometimes

Yes, along the river the map shows swampiness, allowing you to “grope” the floodplain. The location of settlements, which, as a rule, are located outside the floodplain, can also help. In any case, there will be no multi-story buildings anywhere on the floodplain, unless it is an artificial embankment on the former floodplain. The highway “unnecessarily” will also not go along the floodplain, but will go along the terrace; or the indigenous shore. If it crosses a river valley, then its segment on the floodplain will be marked with an embankment sign. A barnyard or a water tower in the floodplain of the river almost unambiguously marks an island of the terrace above the floodplain, which is not expressed in the contour lines of the map, etc.

Drawing the contours of the PTC on a topographic basis most often goes in parallel with the work on aerial photographs and space materials, as well as on industry maps, so many questions are resolved. Let us only note that when working with topographic maps of medium and small scales, it is good to have larger-scale maps for more confident and accurate drawing.

Work with aerial photographs and space materials and industry maps. The use of aerial photographs can be recommended for both large and medium-scale studies. Satellite images are convenient for small- and medium-scale work, and if they are enlarged, also for large-scale work.

Typically, in large-scale studies, black-and-white contact prints of aerial photographs of different scales are used (usually 1:17,000 and 1:12,000, but others are possible - from 1:5000 to 1:60,000) depending on the availability of ready-made negatives in the State Geological Supervision funds, since ordering specially new aerial photography is often impossible due to financial considerations. Materials from more recent flights are selected, preferably early summer, when the contrast in the humidification of different PTCs is recorded most clearly.

Aerial photographs usually clearly show types of areas with their specific tract structure. It is possible to recognize both localities and individual large facies on them. In satellite images covering large territory, different landscapes are already visible, confined to certain tectonic structures, or, perhaps, tectonic structures are “shown through” different pattern landscapes.

Whenever possible, color or spectrozonal images are used, especially to decipher vegetation, as well as (additionally) aerial photographs of previous years of different dates, from which one can trace the speed of certain processes (for example, aeolian, erosion, waterlogging, overgrowth, change of land, changes in location of settlements, etc.). It is also practiced to view paired photographs under a stereoscope. The photographs reveal contours that differ

The shape, phototone, pattern (structure) of a photograph, its shadow.

First of all, natural boundaries associated with changes in nature are identified. A sharp change in the photographic image along rectilinear boundaries often reflects the results economic activity people (change of land, crop rotation fields, etc.). Such boundaries are interesting as the boundaries of derivatives (anthropogenic modifications) of facies and tracts; usually they are also fixed, but in a different way than natural ones (for example, with a dotted line).

When deciphering, both direct signs of objects, directly visible on an aerial photograph, and indirect signs, based on natural connections existing in the hardware and software, are used. For example, if a pine forest is identified on a terrace, then it is likely that it is sandy. Or, if the plowed area near the edge of the beam has a lighter tone than the neighboring ones, then, most likely, its soils are significantly eroded, etc.

Often, a change in pattern or tone is quite understandable and corresponds to either a change in vegetation, or moisture, or the rocks that make up the surface, or several components at once, which can be verified by checking a topographic map and (or) industrial natural maps. But often in office conditions it is not possible to explain the reason for the change in the nature of the image on an aerial photograph, and its interpretation is postponed until the field period.

The decoding results are drawn on a matte film applied over the aerial photograph using a soft pencil and (or) gouache. You can immediately transfer them to the topographical map, complementing or clarifying those contours that were already drawn horizontally on it as forms and elements of relief forms. At the same time, a tabular (working) legend is compiled, where for each selected and numbered contour its main content is revealed: location and relief, rocks, moisture, soils, vegetation. The note indicates whether field clarification of the properties of the PTC is necessary, and what exactly (identification of constituent rocks, soils, etc.).

The compilation of a preliminary medium-scale landscape map is characterized by a lesser degree of interpretation detail. Known difficulties arise in this case due to the different scale of materials. Typically, the scale of aerial photographs is much larger than the map being produced. In this regard, it is more convenient to use not separate contact prints, but sketch montages or, even better, photographic diagrams, or enlarged space photographs (and spaceplanes with horizontal lines applied to them), allowing you to simultaneously view more

; I explore the territory, identify natural territorial complexes on it, and lay them on a topographic base of a selected scale or on a tracing paper (film) superimposed on it. Viewing the entire mass of contact prints of aerial photographs under a stereoscope in this case is practically impossible due to their too large number. However, in some cases this is quite advisable, for example, when identifying boundaries that coincide with the bends of the slopes of the bedrock banks of a river valley, terraces, etc. As a rule, in curriculum Physical geographers, landscape scientists have special courses on interpreting aerial photographs and space images, so we will not dwell on this, we will only name some sources for those interested: The Earth is the planet of people. View from space. - M.: Varyag, 1995. Interpretation of multispectral aerospace images:

£ Scanning system. Fragment. Methodology and results. - Berlin: Akademi-forlag. - M.: Nauka, 1988.

Album of samples of topographic interpretation of aerial photographs

| kov // Proceedings of TsNIIGAiK. - M., 1967. - Issue. 180.

Interpretation of Quaternary deposits. - M., L.: Science,

Very clear illustrations of the results of airborne decoding

I, photographs (especially in mountainous regions) are given by M. N. Petrusevich (1962, 1976). One can also mention the works of V. G. Gospodinov (1961), S. P. Alter (1966), A. A. Vidina (1982), etc.

At any scale of work, to fill the contours with specific content, simultaneously with the analysis of aerial photographs and space materials, special (component) maps available for the study area are used: soil, Quaternary deposits, pre-Quaternary deposits, structural-tectonic, hydrogeological, engineering-geological, geomorphological, maps (plans) forest taxation and others showing vegetation cover. However, vegetation is the component usually most modified by humans. These changes can be short-lived and random, and the maps (and plans) themselves are often too tiled, making them difficult to use. Therefore, materials on the vegetation cover of the territory are used after all others. Particular attention is paid to the types of habitats, for which they use the scales of L. G. Ramensky (1971), V. V. Pogrebnyak (modified by A. A. Vidina, 1974, 1982), ecological series (S. V. Viktorov, 1979) , in order to discern its indigenous variants behind today’s picture of greatly altered vegetation.

In the event of a discrepancy between the contours of special maps and the nature of the photographic image, preference is given to aerial photographic materials, but the issue that has arisen is recorded for further clarification.

Compiled from aerial photographs and (or) space materials and special maps (geological, geomorphological, etc.), preliminary landscape maps, as a rule, have a fairly good drawing of contours, but a schematic legend that is not yet complete and accurate in content.

However, despite all the incompleteness, the legend of the preliminary landscape map should not be a chaotic list of contours of various contents. Already in the preparatory period, one must strive to systematize the material, make an initial classification of PTC, observing the structural-genetic principle and avoiding logical errors.

A. A. Vidina (1973), based on the materials of the Central Russian Expedition of the Faculty of Geography of Moscow State University, developed a typological classification of the morphological parts of plain landscapes (tracts, sub-tracts) for the purposes of large-scale mapping on a scale of 1:10,000-1:100,000. Based on this classification, it is possible to create quite detailed legend in text or tabular form. Fragments of those and other legends of landscape maps of different scales are given in Appendices 3 - 6.

In the process of field work, the main task is to reveal the content of the identified contours (according to their typological groups) and to clarify controversial issues that arose during the analysis of heterogeneous materials. The boundaries of the PTC contours usually change little after field work, since aerial photographs and space materials make it possible to put them on the map even with to a greater extent accuracy than direct observation in the field.

Using a preliminary landscape map, even before going into the field, it is recommended to develop a network of routes and outline points of complex descriptions. A. A. Vidina (1982) considers it possible for large-scale work (1:10,000-1:25,000) in the forest zone of central Russia to assign one working pair (a specialist and a worker or collector) to a one-day route with a length of 2-3 km 20 - 23 points of a complex description (full at the main points and abbreviated at the mapping points). In the forest-steppe zone, with greater complexity in describing the soil profiles of gray forest soils and chernozems, the daily norm is reduced to 12-15 points per working pair, but at the same time the length of the field route increases to 3-4 km. The latter is associated, in our opinion, with less complexity morphological structure landscapes of erosion-denudation plains of the forest-steppe in comparison with landscapes of moraine and moraine-fluvioglacial plains of the forest zone, which makes it possible to make the network of points more sparse.

For 1 km 2, from 2 - 3 to 20 - 25 points can be specified. On average, the required density of points per 1 km 2 in the forest zone is 10-15, in the forest-steppe 6 - 8, and in key areas up to 10-12 points or more. These are slightly higher standards than those given

The calculations given below are borrowed from the experience of soil surveying. Perhaps this is legitimate, since landscape surveying is apparently more complex than soil surveying, at least in the opinion of ["I.I. Mamai, the above standards are underestimated. Landscape scientists have long abandoned what was previously practiced in industry | studies of the regular placement of points on a network of squares, ) since the use of aerial photographs, good topographic maps and other materials and the preparation of preliminary land-| Shaft cards allow you to make this network more rational - { sparse on large contours of a relatively homogeneous territory and denser on areas with small-contour and different nature PTCs. However, the use of computer technology I niks when compiling landscape maps again forces us [to recognize the legitimacy of the method of regular placement of observation points.

Standards for certain types of landscape research work have not yet been developed. For comprehensive interpretation of aerial photographs when compiling a landscape map at a scale of 1: 10,000 for the average developed territory of the central zone of the Russian Plain, A. A. Vidina (1974) determines the norm at 5 -8 km 2 (or 5 -8 dm 2 on the map scale) per person per day. Our work experience; showed that for a scale of 1: 100,000 it is possible to decipher 100 km 2 (or 1 dm 2 on the map scale) in the same time. But no matter how significant the time spent on drawing up preliminary landscape maps is, they are justified by a significant increase in the quality of the work as a whole and shorter deadlines for field work.

Field documentation

The materials of field observations are recorded in a field diary, as well as in journals, forms and other documents that are developed based on the focus, scale of work and other specific features of the expedition.

The diary (along with the field map and forms) is one of | basic documents that require careful storage and careful handling. On right side pages with a simple soft [ pencil, text records are kept very clearly during [ observations, sketches are made on the left side, schematic plans, columns of geological outcrops are drawn up, photographs are recorded, amendments are made related to the text on the right side.

On the first day of work, the field diary must have a completed title page, which indicates: title

Organizations, expeditions, field diary number, last name, first name, patronymic of the researcher, start date of keeping the diary and the number of the point from which the work began, and later - the end date of the work and the number of the last point. At the end title page The postal address and telephone number are recorded so that if the diary is lost, the finder can contact its author. At the end of the diary, at the beginning or end of it, “Contents” is given with the names of the routes and a list of points described in each of them. However, it is better to compile the “Contents” during field work, as each route is completed, indicating the pages (the diary must be numbered in advance).

If the main part of the field material is documented on forms, then only specialized points are recorded in the diaries (see Section 3.7), observations along the route between points, and contour characteristics of identified PTCs that are more complex than the facies (it is described on the form). It is necessary to review field notes every night in order to control their completeness and correctness and primary generalizations of the material.

Usually, when working on an average and especially a large scale, observations at points are of a massive nature, and they are recorded on forms. The advantage of forms over a field diary lies in a strictly defined list of recorded information. The form is a kind of abbreviated observation program. The more strictly the requirement of uniformity and comparability of the collected material is observed, the more correct and accurate conclusions can be drawn based on their processing. Another advantage of the forms is the convenience of “sorting” the material according to the necessary characteristics of the described facies. The disadvantages of the form are its attachment to the “point” (facies) and some of its “formalism”. The latter quality has already been mentioned as positive, helping to process field material, but the rigid form does not always contain everything. The situation may require recording additional facts not provided for in the form columns. That is why, even if forms are available, keeping a field diary remains mandatory for the researcher.

The form(s) of the form(s) are developed during the expedition during the preparatory period or borrowed from existing samples. It can and should change depending on the direction of research and the conditions of the work area. The use of universal forms “for all occasions” is inconvenient. However, the variety of forms of forms should not be unlimited, otherwise the materials from field research from different expeditions may turn out to be poorly comparable. To obtain comparable materials, the most homogeneous information is necessary. You can’t erase anything in both the diary and the forms, you can only cross them out and write again. It is impossible to destroy without a trace records that have appeared

I erroneous, so as not to deprive yourself of the opportunity to think again | over unclear issues. In addition, editing something erased can I cause someone to doubt the authenticity of what is written. By-| on the left is a form, a field map, a diary - these are documents and the attitude towards them must be appropriate.

3.4. Reconnaissance and selection of sites for detailed studies Before starting field research, the leadership of the ex-edition conducts preliminary reconnaissance. Small-scale studies, as a rule, covering very vast territories, are often carried out without reconnaissance, since they themselves are of the nature of route observations, and to a lesser extent - key ones. It is difficult to preface these studies with an even more rapid preliminary examination of the territory. rhetoric. In this case, aerovisual observations from an airplane or helicopter are most effective, but this is not always possible.

For medium-scale studies, reconnaissance is necessary.

Its first task is a preliminary familiarization with the territory and the selection of key areas to be studied in detail? niyu and covering, if possible, all the diversity of landscapes presented in the study area.

The second task is to identify the degree of correspondence between cartographic and aerial photographic material and information obtained from the literature. G tour and fund sources, the actual situation on I terrain. This may also apply to borders. forest areas, arable land, | grasslands, and the presence or absence of roads and populated areas | points, and the nature of the soil, etc. If during such a check } If it turns out that the available materials are complete and can be trusted, then this will significantly facilitate the work and, perhaps, will make it possible to make the previously planned network of routes somewhat more sparse. Otherwise, the amount of work will increase.

Lesson:What is a site plan

1. Introduction

Purpose of the lesson: to find out what types of terrain images there are, what a terrain plan is.

2. Types of images of the earth's surface

Before making a decision on the construction of new factories, schools, sports institutions, on the construction of roads, on the location of agricultural land, it is necessary to have an image of the given area.

A small area can be drawn or photographed, but many objects on the earth's surface will be difficult to identify from such images.

The most common images of the earth's surface are aerial photographs, images from space, maps and site plans.

Rice. 1. Aerial photo

3. Aerial photographs and site plans: similarities and differences

Plan –a drawing of a reduced image of the area, made in conventional symbols on a large scale (usually 1: 5000 and larger). Typically, plans are made for a small area of ​​terrain, several square kilometers in size, and the curvature of the Earth’s surface is not taken into account. The first maps in history were plans. Plans are used in a wide variety of industries and agriculture. When constructing buildings, laying roads and communications, you cannot do without them.

Objects located on the surface (forests, rivers, villages, fields, etc.) will be seen better if the area is photographed from above, for example from an airplane. This image of the area is called an aerial photograph. On it, objects are similar to their true appearance on the ground, their sizes and mutual arrangement. There are many differences between a plan and an aerial photograph. A site plan is a drawing on paper depicting a small area of ​​the earth's surface in a reduced form. The plan differs from other images of the surface in that all objects on it are shown by conventional symbols. In general, it is more convenient and more informative to use a plan.

Aerial photograph and site plan:

Rice. 2. Aerial photograph and site plan

4. Site plan. Conventional signs

Directions on the plan are indicated by an arrow, the tip of which always points north. Typically, north on a plan is at the top, south at the bottom, east at the right, and west at the left. Using the plan, you can determine the relative position of objects on the sides of the horizon and measure the distance between them using a single scale.

Rice. 3. Site plan

Rice. 4. Area plan and symbols for it

The conventional signs of the plan are, firstly, simple, secondly, unlike each other, and thirdly, they resemble the objects themselves. Under these conditions they are clear to everyone who reads the plan. So, rivers and lakes are shown blue water, and forests - green - the color of vegetation. There is no special sign for fields and vegetable gardens, so such areas are left white on the plan. The grassland symbol resembles stalks of grass. Sands are represented by brown dots. Small streams, roads, narrow streets are depicted with conventional signs in the form of lines. Such symbols are generally accepted. They are used on all terrain plans.

Rice. 5. Conventional signs

Groups of symbols:

1. Area

In the mid-19th century, a hot air balloon rose over the capital of France, Paris, and photographer Nadar took the first bird's-eye view of the city. The Parisians saw what the city blocks, streets, and the Seine River, on the banks of which the city grew up, looked like from above. This is how the first aerial photographs appeared - reduced photographic images of a section of the earth's surface (er - "air" in French).

Currently, aerial photographs are taken from airplanes and unmanned aerial vehicles, including multicopters.

An aerial photograph shows houses, roads, bridges, rivers and ravines, fields and forests - in a word, everything that we see on the plan and map. Learning to recognize geographical objects in a photo means learning decipher aerial photograph. Not only the objects are important, but also the tone of the image: the wetter, damper the earth, the darker the tone of the image. The water in the river or lake will be completely dark in the photo. It is impossible to see on the map whether the soil in the field is wet or not. Yes, this is not required; in a few days the soil on the field may dry out.

If the plane flies high above the ground, then the scale of the aerial photograph turns out to be small. If the plane is flying low, the aerial photograph will be on a large scale, showing a small area in great detail. During aerial photography, the aircraft flies in a given direction and takes pictures at regular intervals. Then it turns around and flies back parallel to its recent path, again photographing the earth. Adjacent aerial photographs are glued together and, using them, a plan or map is drawn.

A map is a reduced generalized image of the earth's surface. For the image on the map, they select the most important, the most significant, that which will not change in a week. The names of the rivers are written on the map, settlements, main roads, the plans show both the direction of the river flow and the nature of the road - asphalt, dirt, etc. Material from the site

The globe quite accurately displays the outlines of the Earth's landmass, but it is not always convenient to use. It is more practical to give a drawing of the Earth and its parts on a plane, paper.

Let us consider in the atlas an image of the Earth's surface - a drawing and plan of the area (Fig. 14, 15), aerial photographs (Fig. 16), a satellite image (Fig. 17) and a geographical map (Fig. 18). How are they different from each other?

Aerial photo is a photograph of the area that is taken from an airplane or other aircraft using a special aerial camera on an appropriate scale.

Aerial photography is used during geographical and geological research, engineering prospecting work, as well as in the preparation of topographic maps.

Space photo is a photograph of the earth's surface or the entire planet, which is taken with automatic photographic equipment from artificial earth satellites.

Space images made it possible to compile a new type of maps (cosmophoto maps). On their basis, such a branch of science as space cartography is developing. In particular, there is detailed maps Moon, Venus, Mercury, Mars. On the terrain plan, all items and objects are reproduced with generally accepted symbols.

Site plan - this is an image small area terrain using symbols and to scale.

Rice. 16. Aerial photograph of the area

Rice. 17. Space photo

On a geographical map, as well as on a terrain plan, objects are also shown by symbols.

Geographic map - this is an image of the required territory or the entire planet using conventional signs and on a certain scale.

The set of conventional signs and their explanations is called map legend. All types of conventional signs are divided into contour, out-of-scale, linear. Outline marks convey the actual dimensions of an object and consist of an outline filled with color or shading. For example, a forest, swamp, lake - on a terrain plan, mountains, plains, contours of continents - on a geographical map . Off-scale signs as geometric shapes, symbols, drawings show objects that cannot be indicated on the scale of a plan or map. For example, a spring, a well, a school on a terrain plan, signs of minerals and settlements, mountain peaks . Linear signs show linear objects on the plan and map: roads, rivers, borders, etc. On a scale they show only their length, but not their width. Depending on the size of the territory depicted and the size of the map itself, different scales are used. The smaller the territory and the more details in its reproduction, the larger the scale of the map. It is called large scale. This is the scale of site plans (1: 5000 or more). There are also large-scale topographic maps(from 1:5000 to 1:200000) (Fig. 19). In Fig. 19 - the scale is larger, and in Fig. 18 - less. Such maps depict a small territory in detail. They are used in military affairs, construction, when laying roads, in agriculture, hiking trips etc. Maps with a scale from 1:200000 to 1:1000000 are called medium-scale(Fig. 20).

Rice. 18. Physical card

Rice. 19. Topographic map(scale 1: 10,000)

But most often a person needs to show on a map vast territories of continents, individual countries or their regions, and sometimes the entire planet. Then they use a small scale, and the maps are called small-scale(Fig. 21). School atlas maps, wall maps - small-scale. For example, the scale of the map of the hemispheres in the school atlas is 1:90,000,000 (900 km in 1 cm), the map of Ukraine is 1:6,000,000 (60 km in 1 cm). Please note that the scale of the first map is smaller, and the second one is larger.

It is impossible to show all the smallest objects on the ground on a plan and map. They would make it difficult to read the images. Therefore, only the main ones are put on the plan and map, i.e. the image is summarized. The smaller the scale of the map, the greater the generality. Material from the site

Plan and map - this is a reduced image of the earth's surface on a plane, made to scale.

Geographic maps depicting natural objects (continents, oceans, mountains, plains, rivers, lakes, etc.) are called physical. For example, physical map hemispheres, physical map of Ukraine.

There are several types of images of the Earth or its individual sections: a globe, a terrain plan, geographic map, drawing, aerial photo, space image.

On this page there is material on the following topics:

• What is more accurate: a physical map or an aerial photograph?

• Aerial photo and map

• What is the difference between an aerial photograph and a plan?

• What is the difference between photographs from space and aerial photographs?

• What is the difference between an aerial photograph and a satellite photograph?

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