Built-up areas representation on topographic map
Content rules of topographic maps
Digital topographic map and its requirements
Growth representation on topographic maps
Hydrography representation on topographic map
Object representation on topographic map
Principles of digital topographic map classification
Programs for working with raster maps
Road representation on topographic map
Soil representation on topographic map
The notion of a map
The process of digital topographic maps creation
Growth representation on topographic maps
Main groups of growth
While representing growth on topographic maps it is divided in the following groups: woody (woods, groves, separate trees), and shrubby; subshrubby, grassy, mossy, and lichen; artificial plantings (gardens, parks, plantations). A complex of trees with the height more than 4 meter and crown density more than 0,2 (crown density – is ratio of crowns square project of all trees of some territory to square of the territory) is a wood. A complex of trees with crown density less than 0,2 is called sparse growth of trees.
Wood structure is defined by the quantity of trees of various wood species in total number of trunks, showed in per cents. Wood where no less than 80 per cents of trees belong to one type is called pure wood. The rest 20 per cents of trees are called admixtures. According to the species woods are divided into conifers, deciduous, and mixed. Species composition influences on height, thickness and crown density. Wood’s age, trees’ height and thickness are interrelated.
Approximate division of forests according to the age, height and thickness is given in the table №1. Tree thickness is usually measured at men’s chest.
|Wood age||Tree height, m||Tree thickness, cm|
|old||more than 10||more than 20|
According to the shape, the following types of trees are distinguished: those, which do not have underbrush and many-tiered one where trees’ and shrubs’ crowns form two, tree or more tiers. Wood’s density is characterized by average distance between trees and crown density (table №2).
|Wood density||Average distance between trees, m||Crown density|
|dense||less than 4||more than 0,5|
|sparse growth of trees||more than 9||less than 0,2|
Shrubs are woody plants with the height up to 4 meters. It has a lot of stems, growing from the root. Species structure, height and thickness are the main characteristics of the shrubs. Undersized shrubs with the height up to 0,8 meters are called shrubs. They usually grow in flat and mountain tundra (polar birch, polar willow, blueberry, heather, wild rosemary, etc.), and also in marshes (bilberry, cowberry).
According to the place of vegetation grassy growth is divided into meadowy and steppe, according to the height – short(less than 1 meter) and tall (more than 1 meter). Mossy and lichen growth grows in tundra region, but can be also found in marshes, woods, edges of a mountain (mountain tundra). In tundra moss usually grow in low and humid places, lichen – high and dry places.
To culture growth belong numerous artificial plantings and crops of cultural plants (orchards, citrus fruits plantations, mulberries, fruit-trees, vineyards, plantations of tea, crops of field and garden cultures).
Peculiarities of growth representation on topographic maps
All types of growth in some definite way influence on locality passage conditions out of roads for wheeled and caterpillar cars, on camouflage conditions from land and air outlook.
Wood with square of 10 square meters and more in woody region and 4 square meters in densely populated region are represented on topographic maps in green color.
Undersized woods, young growth, woody pinetum with square of 10 square meters and more are represented on topographic map by means of special conventional sighs of green color, but of more light tone. Areas of thin, cutting down, burnt and deadwood woods, situated among woodland are represented by means of special conventional signs without painting when its square is 25 square meters or more in the map scale, and situated in stretch of open country and being reference points even of lesser square.
Wind-fallen trees – regions in forest situated among woodland where more than half of trees felt with square 25 square meters and with square 10 square meters in stretch of open country are represented on topographic map by means of tint color. Area where less than a half trees felt and wood in this area is difficult to traverse is represented with the sign of wind-fallen trees (lines).
Separate standing trees that have reference significance are represented on topographic maps by means of special conventional signs with division into: conifers and deciduous.
Undersized woods, young growth, woody pinetum while representing on topographic map are divided into conifers, deciduous and mixed. The dominating species are represented with special shorten signs, but if there is no specially accepted sign, the name of species is fully written.
While representing mixed wood, two main species are indicated, besides, the most important is written first.
Average height of trees in meters, average trunks’ thickness measured at men’s chest, average distance between trees is the characteristics of wood. While representing undersized woods, young growth, and woody pinetum with square 10 square meters and more in map scale only average height of trees is given; if trees have height less than 1 meter it is given in a fraction of a meter. Woodlands’ characteristics (wind-fallen trees, water-logged areas, felling) are represented in combination of corresponding conventional signs.
Cuttings are usually represented on topographic maps. Cutting with width 20 meters and more, 40 meters and more, 60 meters and more on topographic maps 1:25 000, 1:50 000, 1:100 000 correspondingly are represented by means of two thin broken lines in accordance to its real width in topographic map scale. Cutting representation is accompanied by width sign. Numbers of woody quarters, indicated on quarter posts, placed at roads crossings are to facilitate orientation in wood.
Shrubs while representing on topographic map are divided into dense bush or groups of bushes or just separate bushes. Dense bushes of chaparral, dense bushes and separate bushes of elfin wood and haloxylon, narrow shrub lines and hedges are represented by means of special conventional signs.
Dense bushes of shrubs are represented by means of conventional signs of background light green stain. Its representation is accompanied by sign of species (conifers, deciduous, mixed) and average shrub height. Separate bushes that have reference significance are represented by means of circle that corresponds to its real position. Narrow shrub lines, hedges are represented if they are situated along roads, rivers, canals, ditches or when they have reference significance.
Grassy growth while representing on topographic map is divided into meadowy, low and high (more than 1 meter) and steppe grass. Cany and reedy bushes are represented on topographic map by means of special conventional signs. Shrubby growth (blueberry, cowberry, heather, wild rosemary) are represented only on topographic maps with scale 1:25 000. Mossy and lichen growth is represented on topographic maps with scale 1:25 000 by means of special conventional signs, on topographic maps with scale 1:50 000 – 1:100 000 by means of some common conventional sign.
Areas of grassy, shrubby, mossy, lichen growth are represented on topographic map with scale 1:25 000 if its square is 25 square meters or more in map scale. Separate areas of such growth are represented if they have reference significance and square 10 square meters or more. Areas of non swamped meadows and steppe grassy growth are represented on topographic maps with scale 1:50 000 – 1:100 000, only when depicting locality with small amount of contours.
Separate areas of cany and reedy bushes, damp areas of meadows, waterlogged areas without growth which have reference significance or essential while characterizing locality are represented on topographic map by means of contours. Steppe (grassy) and subshrubby growth in mountains are represented only on topographic map with scale 1:25 000.
Orchards, citrus fruit gardens and trees plantations are represented on topographic map by means of contours out of built-up areas. Vineyards, berry gardens and shrubby plantations (tea, roses, etc.) are represented on topographic map by means of contour when its square is 25 square meter or more in map scale. Grassy industrial crops plantations (hop, rice, etc.) that are always very damp are represented on topographic maps when its square is 25 square meter or more in map scale. Representation of grassy industrial crops plantations with square more than 1 square centimeter is accompanied by the sign (hop, rose, etc.).