Under coniferous forests, characteristic soil types are formed, which have their own characteristics. Let us consider what features soils form under coniferous forests have, what types are most common, the conditions of formation and characteristics of the soil of boreal, dry coniferous and mountain forests. What types of plants make up the vegetation of such forests.
Peculiarities
A moderately cold climate, flat or mountainous terrain, leaching water regime, and seasonal freezing of the soil play an active role in the origin of soils in coniferous forests.The underlying layer formed by fallen pine needles contains a low amount of nitrogen and organic acids formed as a result of the activity of fungi.
Acids, due to the leaching regime, are washed into the lower layers of the soil. Such conditions form podzolic soils, characteristic of the forest zone. It cannot be said that forest lands with conifers are rich in humus; the activity of microorganisms in them is slow. They also don't have many nutrients.
The forest soil profile consists of litter 3-5 cm thick and has a brown color. The litter consists mainly of fallen pine needles, leaves of shrubs, remains of grass, lichens and mosses. The second, gray-brown humus-eluvial layer extends to a depth of 5-10 cm. Behind it is a fine-grained podzolic horizon, dense, without a clear structure, light ash color, its thickness is 10-20 cm. Beneath it is a yellow- brown illuvial horizon under which the source rock is located.
Most common types
Coniferous forest lands are divided into different types, they are located under boreal, dry coniferous and montane forests. They are formed under the influence of different soil-forming and climatic conditions.
Boreal forest soil
It occupies a little more than half of the territory of Russia. The climatic conditions here are varied, severe frosts are common in winter, and the average temperature in summer is 10-20 ºС. Humidification prevails over evaporation, although there is not much precipitation. Boreal soils are characterized by poor drainage and low content of nutrients.
Such conditions are suitable for the growth of coniferous vegetation, but a short warm period reduces the biological activity of microorganisms.In forest areas you can often find soils covered with rotted organic matter and peat; they are well moistened all year round.
Soil of dry coniferous forests
The litter consists of needles, leaves, bark debris and cones. Mushrooms grow well in it, and a lot of soil animals live in it. They process organic matter and return it to the soil in the form of mineral elements, reducing high acidity. The process of decay of organic matter continues in the lower layers, from where the roots of coniferous plants obtain food.
In dry forests, mainly pine trees grow, which prefer neutral or slightly acidic soil. They do not form dense massifs and are sparsely located; this is what distinguishes dry forests from boreal forests.
Coniferous forests in the mountains
Soils in mountainous areas are thin, especially on slopes, contain a lot of crushed stone, primary minerals, and the profile is not clearly defined. The characteristics and distribution of mountain soils depend on altitudinal zones, changes in air temperature, and volume of precipitation. Under forests with coniferous trees, brown soils are formed, dense, with a thin fertile layer, which does not contain a large amount of nutrients.
Vegetation
The land under the forests is infertile, but tall trees grow well on it - pines, cedars, larch, spruce, fir. Alder, birch and aspen are also found, but in much smaller quantities. In the southern taiga, ash, oak, beech, linden, hornbeam, maple, elm and other broad-leaved species alternate with conifers.
Herbaceous vegetation grows under trees, under the forest canopy, and in floodplain and upland meadows. In the northern taiga and in the West Siberian Lowland, swamps with their characteristic vegetation are common.
Soils under conifers are formed under the influence of moderately low temperatures, flat or mountainous terrain, predominantly leaching water regime, and winter freezing. Humus and the top layer are formed from fallen pine needles and leaves of shrubs, have a brown color, dense composition, the soil is mainly acidic, thin, and infertile. It does not contain a large amount of humus and mineral components, therefore it has practically no economic value.
