How to develop a wetland. Drainage of swamps

The idea to restore drained peat bogs in the Moscow region will require significant funds and gigantic volumes of water, the sources of which are limited in the central part of Russia, Corresponding Member of the Russian Academy of Sciences Kirill Dyakonov, head of the Department of Physical Geography and Landscape Science of the Faculty of Geography of Moscow State University, told RIA Novosti.

Bogs are found in almost all natural areas and are very diverse. They differ in vegetation cover, structure of peat deposits, location in relief, as well as in terms of water and mineral nutrition.

According to one of the classifications, according to the characteristics of peat accumulation, five categories of bogs are distinguished:
- peat-free bogs, where peat does not accumulate due to the peculiarities of the natural environment (for example, delta and floodplain bogs, where peat is not formed due to the drift and drift of residues);
- shallow (polygonal) swamps - peat accumulation is slow; these swamps do not create their own hydrological system and microrelief;
- mosaic-focal peat bogs, where peat deposits occur unevenly throughout the entire area (hilly bogs of the North, ryam and bog bogs of Siberia);
- typical peat bogs (swamps of the forest zone);
- peat bogs - peat accumulation occurs so intensively that it practically does not depend on the relief conditions (swamps in the coastal regions of Western Europe, in a less pronounced form of swamps of Kamchatka and Sakhalin).

In our large country, marshes and wetlands occupy significant areas. On swampy soils, ordinary plants cannot grow and develop, which need oxygen all the time to feed their underground parts - roots and rhizomes. Stagnant, still water is quickly deprived of oxygen, and most plants die. Only those who have managed to adapt to life in the swamp survive - bog plants.

Meanwhile, in terms of their chemical composition, bog soils are extremely fertile. They can produce high yields of a wide variety of agricultural crops. But for this you must first drain the swamp. Then barren lands harmful to human health will turn into richest fields and pastures. Fat fields will sprinkle where only stunted marsh grasses and stunted bushes have recently grown.

A lot of work is being done in our country to drain and reclaim swamps. The agriculture of the socialist country has already received millions of hectares of new fertile land.
The drainage of swamps is now almost completely mechanized. Soviet scientists and engineers have created many wonderful machines that perform all the hard, tedious and monotonous work for people.

How are swamps drained?

First of all, you need to remove excess moisture from the soil, that is, give it a runoff. And the water should, of course, drain into the nearest river. Therefore, first of all, it is necessary to deepen and widen the bed of such a river, and in some places to straighten it. Here you have to remove the soil mainly from under the water.

Nowadays, floating and land excavators, as well as dredging installations, take out soil from the river.

Floating excavators are used in cases where the width of the river allows the excavated soil to be dumped onto the shore. This soil thrown out by the excavator is leveled with bulldozers.

Floating dredgers, depending on their performance, are used both on large and small rivers. The soil they extracted from the bottom of the river, mixed with water - the pulp - is pumped through pipes to the shore and poured over the soil surface. You don't need a bulldozer here.

But stagnant bog water will not flow into the river by itself, even after its channel is deepened and widened. For drainage, it is necessary to lay more channels throughout the swamp area. First, they dig the main, that is, the main, channels, then the collector ones. The latter collect water flowing down from the swamp through a shallow closed or open drainage network and drain it into the main canal.

An open network of shallow drainage ditches serves to receive and drain surface water into collector canals, as well as to lower the groundwater level in the area to be drained.

Along with an open network of ditches, a closed network - drainage is used for draining swamps. They are boardwalk, pottery, fascinated, or mole. Board drainage is made from planks that are hammered together in the form of rectangular pipes. The potter's one consists of pottery, i.e., burnt, clay pipes. Fashinny drainage - from brushwood of various tree species, cleared of leaves and small twigs. And, finally, the mole is a system of underground canals that resemble mole passages.

Trunk and collector channels with a depth of 1.5 to 2.5 m are laid by excavators specially adapted to work on swampy ground.

Plow trenchers work on the laying of an open shallow drainage network of ditches. This is a high-performance machine: in an hour it can dig ditches up to 2 km long and up to 80-100 cm deep.

A trench for laying drainage is dug with the help of a bucket excavator or a plow trencher, then drainage is lowered into it and covered with earth from above.

Mole plows and mole-drainage machines have been created for laying mole drainage. They are set in motion by a tractor specially equipped for work on swampy ground.

Immediately after the canals are laid, their slopes are reinforced with sod or sowed with grasses to avoid landslides and landslides.

But time passes, and open canals and ditches are gradually covered with sand or silt, overgrown with marsh grasses, become shallow, destroyed and, as a result, begin to drain water poorly, or even become clogged. We have to periodically clean and repair them.

So the swamp has been drained. All of it was covered with a network of large and small channels. Stagnant water that has accumulated in the soil for years flows freely through these channels into the nearest river. But this is only the first part of the work of ameliorators - this is the name of the people involved in the radical improvement of the natural conditions of lands with an unfavorable water regime. Now the drained swamp needs to be mastered, prepared for sowing cultivated plants. For the repair and cleaning of ditches and canals, special cleaning machines are used: some for cleaning ditches of a shallow drainage network, others for cleaning collector and main canals.

The first step is to clear the soil from small shrubs, stumps, bumps and wood debris. You can't do much here with an ax and a shovel - this is a very laborious task.

A brush cutter mounted on a tractor easily cuts off bushes and small trees, removes hummocks.

However, hedge trimmers are beneficial to use in cases where the swamp is overgrown not only with shrubs, but also with small forests. If the shrub is without undergrowth, it is simply buried deep into the ground. This work is performed by a bush plowing unit. Such a hydraulically controlled unit, driven by a tractor, consists of two parts: a hollow drum and a ski with a knife are hung in front of the tractor, and the plow body is behind. The drum, rotating, tilts the bush forward and presses it to the soil surface; the knife cuts the layer with rhizomes in a vertical plane, and the plow body wraps the layer and plows the bushes to a depth of 20 to 50 cm.

Grubbing up stumps and removing wood residues is one of the most difficult tasks in the development of drained swamps. Stumps are uprooted with a straight pull of a tractor with hooks on chains or cables, or with a grubber, or a powerful bulldozer that turns out huge stumps, or with a grubber-collector.

After cleaning the drained area from shrubs, stumps, bumps and wood residues, it begins to be prepared for agricultural use. It includes three processes: plowing, cutting, and rolling.

The plowing of peat soils in a drained bog should be deep, with full coverage of the surface vegetation cover. For this, special swamp plows with a wide grip are used, which plow the soil to a depth of 50 cm, while wrapping the layer and embedding all the vegetation deep into the soil.

The layer of earth wrapped in a plow must then be loosened to the greatest possible depth so that oxygen can freely penetrate into the soil. The seam is loosened with disc harrows or special milling machines.

Then the surface of the drained swamp is rolled - leveled with special swamp filling rollers.

If the purchased suburban area is located on a peat bog, its owners will have to perform a number of works to improve the soil on it. The land in such places, unfortunately, cannot be considered too suitable for growing all kinds of agricultural crops. The soil in peatlands contains very little oxygen, which replaces methane. Also, such areas in spring and autumn turn into a real swamp due to flooding. How to drain a peat allotment, if necessary, will be discussed later in the article.

Improvement Ways

In some cases, the problem of waterlogged land can be solved in a very simple way - by adding a certain amount of land brought from outside. But using such a technique, of course, is possible only when water is collected on the site due to the fact that it is located in a lowland and has a relatively small size. In all other cases, it is necessary to drain water from the allotment.

The answer to the question of how to drain the site, in this case, can be two technologies:

superficial;

with pipe laying.

The first method is considered the easiest. Do-it-yourself open drainage in a swampy area will be absolutely easy to do. But using pipes, you can equip a more efficient drainage system.

Ditch retraction

This method is a good answer to the question of how to drain a peat bog. The advantage of this method, among other things, is that when it is used to drain water from the site, the owners will not have to spend a penny. For drainage, in this case, a ditch about 50 cm wide and at least 1 m deep is dug along the edge of the allotment on the side that is located below the others.

If there is a slightly higher, also swampy neighboring area nearby, a trench should be made on the border with it. This will close access to water from someone else's land.

Subsequently, in the process of performing various kinds of channels on the site, it will be necessary to fill all kinds of construction and garden waste. This can be, for example, stones, broken brick, weeds, etc.

Benefits of using pipes

The open way of draining water through ditches is simple and cheap. However, this technique is used only in not very swampy areas. In all other cases, it is advisable to equip plots with full-fledged drainage systems using perforated pipes.

The answer to the question of how to drain a swamp in a garden, such technology in most cases is simply ideal. The pluses of such diverting networks, among other things, include:

more uniform and faster regulation of the water balance in the soil;

the ability to cover absolutely the entire area of \u200b\u200bthe site.

When applied, such sleeves pass underground. This does not reduce the usable area of \u200b\u200bthe site. When growing garden crops on such an allotment, beds can be made, including directly above the pipes.

How to set up a closed system

In this case, ditches are also dug on the site in advance to drain water. In this case, the main trench is located along the perimeter of the allotment. Next, ditches are dug over the area of \u200b\u200bthe site.

When using this method of drainage, a waterproofer is laid at the bottom of dug trenches - a thick film or roofing material. Next, a layer of medium-sized rubble or pebbles is poured into the ditches. Perforated pipes are laid on top. In order to prevent the holes of such drainage lines from clogging up in the future, they are pre-wrapped with geotextiles.

Connect pipes at the points of convergence or intersection of the ditches using tees or angle fittings. Above these network elements, viewing wells made of plastic or concrete are mandatory. If there are such additions in the system, in the future it will be very easy to remove the blockages that appear in the lines and clean them from the accumulated sludge.

What you need to know

Of course, in order for the water to leave in the subsequent section through pipes by gravity, they must be laid at a slope. Otherwise, it will not work to drain the allotment. Unfortunately, it is impossible to mount the drainage mains under a too steep slope. In this case, the pipes will subsequently silt very quickly. The slope of the drainage channels should also not be made too small. Otherwise, the system will subsequently work ineffectively.

In most cases, when arranging garden drainage networks, pipes are laid at an angle of 0.5 to 3 cm per linear meter. You should not deviate from these parameters up or down.

Receiving well

Thus, we have figured out how to drain the site using pipes. But where can you put the extra water itself? Drain it from the site, if it is located on the outskirts, you can simply behind its side-altars - in some ravine, stream or pond. But if there are neighboring plots next to the swampy garden, you will have to equip a special well to receive wastewater. If desired, such a container can be built on a site located on the outskirts. After all, the water collected during drainage can subsequently be used to irrigate the same beds.

Receiving wells are equipped at the lowest point of the suburban area using the following technology:

a hole is dug in the ground, into which the main drainage trench is inserted;

the bottom and walls of the pit are concreted with a layer of 5-10 cm.

Of course, in the concrete structures of the well, when pouring, holes should be provided for the pipe plant.

Instead of a concrete structure, a plastic one can be used when arranging a drainage system. Such a container will be easy to purchase from companies specializing in the supply of equipment for drainage systems.

Receiving pond

In most cases, the owners of peat bog gardens, of course, equip a well to drain water. But instead of it, if desired, you can make an artificial reservoir on the site - a beautiful decorative pond. In this case, a foundation pit is also pre-dug in the ground, but wider.

The bottom and walls of the pit for arrangement on the site of an artificial reservoir are thoroughly cleaned of roots and stones. Next, the pit is covered with a durable waterproofing material - best of all with a thick film. Drainage pipes are led out through the holes in the film into the pond. You can disguise them at the bottom, for example, with beautiful stones or some kind of aquatic plants. In the summer, it will be possible to release unpretentious fish from the aquarium into this reservoir. Spectacular marsh plants are usually planted around the pond.

The main difficulty

In principle, as you can see, the answer to the question of how to drain the area from water with your own hands is quite simple. The most difficult task in this case, most likely, will be physically difficult earthworks. After all, there are actually a lot of ditches on the site. However, in order for such a system to work as efficiently as possible, trenching on the site, of course, should first of all be in the right places.

To entrust the project of arranging the drainage system of a swampy allotment is best, of course, to a specialist. A professional will be able to take into account all the nuances of the relief of this particular area. However, projects of drainage systems in suburban areas are, unfortunately, quite expensive. If there is no money to order a pipe laying plan, you can try to develop it yourself. In order to find out where is the best place to dig drainage trenches, you will have to wait for the first heavy rain. Observing the streams flowing along the ground, it will be possible to accurately determine the optimal location of the trenches.

How to drain a swamp: using moisture-loving plants

Of course, in most cases it is possible to drain a wetland area only by cardinal methods - by arranging ditches or laying pipes. But as an additional measure in such a garden, it is also worth planting plants that draw a lot of water from the ground. These can be, for example, willows, birches or maples. Such trees, since they have a considerable height, are planted, of course, usually on the north side of the allotment. Otherwise, in the future, they will obstruct the plantings, which, in turn, can easily lead to a decrease in the yield of garden and garden crops.

The high level of groundwater at the site can also be reduced with the help of shrubs. For example, hawthorn, rosehip, bladder, and irga can take a lot of water from the soil. Such plants can be planted around the perimeter of the site to create a hedge.

Methane in soil

Of course, after draining with open drainage or by laying pipes, the land on the site will in any case become more suitable in composition for growing garden and horticultural crops. But in order to further improve its quality, site owners will have to:

scatter a mixture of clay and sand over the area with a thin layer;

carefully dig up the allotment using a shovel or, preferably, a motor-cultivator.

Of course, a very good solution would be to scatter around the site, in addition to clay and sand, before digging, also manure mixed with sawdust. This will not only improve the structure of the soil, but also make it more fertile and nutritious. The introduction of various kinds of mineral fertilizers into the soil will also make it more suitable for growing garden and garden plants.

The advantages of peat bogs

So, we found out how to drain the area from water with our own hands and improve the soil on it. Such an allotment can bring trouble to its owner, of course, a lot. However, peatlands, in comparison with other types of soils, have their own advantages. For example, in such areas, plants usually tolerate winters much better. The soil on peat bogs is frozen slowly, in thin layers. At the same time, the soil on such allotments never freezes too deeply. So on such an allotment, after draining it, you can plant, for example, heat-loving roses, apricots, etc.

Waterlogged lands, swamps and causes of waterlogging

The main tasks of draining swamps, wetlands and excessively wetlands are reduced to creating optimal conditions for the growth of agricultural crops. Bogs are understood as areas of land that are constantly or periodically in a state of excessive moisture, and within which the thickness of peat reaches 15–20 cm.

Bogs are subdivided into lowland, raised bogs and transitional bogs.

Lowland swamps are formed in floodplains of rivers, near lakes. In such bogs, peat has an increased ash content (up to 30% of the dry matter mass). After draining of this type of bog, peatlands become very valuable agricultural lands, as they contain up to 3.5% nitrogen, up to 1.7% phosphorus and up to 0.25 potassium.

Upper bogs are common in watersheds and feed on precipitation and melt water. Their characteristic vegetation is mosses. Peat from raised bogs has a low ash content - no more than 3–5% of dry matter mass, it is characterized by an acidic reaction (pH 3.5–5). After drainage and inclusion of raised bogs into agricultural circulation, the introduction of organic and mineral fertilizers is required.

Bogs of a transitional type occupy an intermediate position between lowland and raised bogs and are formed in areas that are subject to temporary moisture.

The main reasons for waterlogging or excessive moisture in territories are precipitation and unregulated surface runoff, which contribute to the accumulation of excess moisture in the territory; surface water flowing from watersheds or rivers (in a flood); ground waters occurring close to the earth's surface. All this, ultimately, creates favorable conditions for the development of bogs or excessively moist soils, and for the normal development of plants in such areas, drainage measures are required.

If the main reason for waterlogging or excessive soil moisture is surface water, then in this case the tasks of drainage measures are:

1) acceleration and regulation of the flow of these waters using open channels;

2) interception of surface runoff and flood waters by ditches; protection against flood waters is carried out through the construction of dams.

With excessive moistening of territories due to groundwater, the drainage task is reduced to:

1) accelerating the outflow of groundwater by lowering groundwater levels using drains;

2) interception of an underground stream in elevated areas, leaking "from the side", by fishing ditches or drains.

The designed drainage must provide the required drainage rate - lowering the groundwater level below the earth's surface by an amount that provides a favorable water-salt regime for the growth of crops throughout the growing season. The drainage rate depends on the type of crops, climatic conditions and soil structure.

Table 8 shows the average drainage rates for the cultivation of some agricultural crops in the conditions of central Russia and the Leningrad region.

Table 8

Average drainage rates for agricultural crops

The drainage network is a complex of engineering structures and devices with the help of which the required drainage rate is achieved. It includes:

1. Fencing network - for intercepting and diverting surface and groundwater entering the drained area from the outside (upland ditches, dams, etc.)

2. Drainage (regulating) network - to collect and remove excess surface and groundwater from the drained area (a number of open ditches and closed drains)

3. Water supply network - for transporting water from the protective and drainage network outside the drained area to the water intake (drainage and main ditches);

4. Water intakes - for receiving water collected by the drainage network (rivers, lakes, ravines).

The drainage network consists of open ditches or closed drains located at a certain distance and depth, which intercept or absorb excess surface or soil-ground water in the drained area. The depth of the drainage network elements and the distance between them should be such that, on the one hand, ensure the drainage rate, and on the other, do not interfere with the normal operation of agricultural machines.

To drain agricultural areas, open or closed horizontal drainage is usually involved.

6.2.2 Drying with open channels

Open drainage or drainage by open canals is the simplest and cheapest way to drain swampy and excessively wetlands. Depending on the purpose, these canals are drainage (used to lower the groundwater level) and collecting (to accelerate surface runoff).

The location of drainage canals in the drained area depends on soil, topographic conditions, the planned use of drained land (vegetable gardens, orchards, arable land, etc.).

Drainage canals are usually cut at an acute angle to the horizontal of the terrain, and in case of groundwater feeding of swamps - at an acute or right angle to the direction of the ground flow. The depth of shallow open ditches (as well as the distance between the ditches) is determined by the required drainage rates for certain crops. The depth of ditches in drained meadows and pastures is 0.8–1.0 m, in fields - 1.0–1.2 m, in gardens - 1.2 m. The distances between the canals when draining bogs in the non-chernozem zone of Russia are given in table 9.

In Russia, there is extensive experience in the drainage of floodplain bogs and wetlands also by single canals, which are penetrated to great depths (more than 1.5–2.0 m). Such a ditch ensures the spread of the drainage action to the side of it for 500-2000 m and allows the area of \u200b\u200bthe territory to be drained without additional involvement of a small systematic network.

In addition to permanent open ditches, temporary ditches or furrows are also involved in the drainage of excessively humid areas. They are traversed by special trenchers across the slope with a slope of about 0.001 and are periodically eliminated (buried) - for the period of planting or harvesting.

The disadvantages of open drainage are that they interfere with the normal operation of agricultural machines, occupy useful agricultural areas, and quickly fail them as a result of clogging, silting, overgrowing, etc.

In this regard, in the practice of agriculture, such drainage devices are trying to be attracted only if necessary in small fields. In large fields, open trenches are mainly used to collect water with closed drainage systems.