DRAINAGE OF BOGS IN TOMSK OBLAST FOR AGRICULTURE

V. L. Kudryavtsev

In Tomsk Oblast, the first drainage project for agricultural use was the Shegaro-Iksinskoye bog.

The drained bog, with an area of 1032 hectares, is part of the enormous Shegaro-Iksinskoye bog, located on the watershed of the Shegarka and Iksa rivers, from which the bog takes its name.

The large, almost treeless plain of the bog had long attracted the attention of the collective-farm workers. In the driest years, hay grass was mowed along the margins of this bog; and in 1956, as much as 178 hectares were plowed, and about 25 ha were sown with winter rye. The rye sprouted very well, but in spring it was waterlogged, and the experiment in developing the bog without drainage proved unsuccessful.

Taking into account the request of the collective-farm board, the Water Management Department of the Tomsk Regional Executive Committee in May 1963 approved the assignment for designing the drainage of the bog, issued by the Krivosheinsky Production Administration of the Tomsk Land-Management Expedition.

During the summer of 1963, the author of the present article carried out a thorough survey of the drainage site; a plane-table survey at a scale of 1:10000 was made, manual drilling of boreholes was performed, and in the winter of 1963–64 a drainage design was prepared.

The soil survey was carried out by student M. F. Razumnikov of the Tomsk Pedagogical Institute; the geobotanical survey—by university student V. R. Lykova.

The drained part of the bog is the eastern margin of the enormous raised Shegaro-Iksinskoye bog and is situated on the lands of the “Pobeda” collective farm in Krivosheinsky District, Tomsk Oblast. The drainage area has a fairly compact shape, extending 3 and 3.5 km in the latitudinal and meridional directions.

The relief of the drained tract is calm; the greatest difference in ground-surface elevations does not exceed 1–1.5 meters. The elevated places are small islands of mineral soil, as a rule covered with birch-aspen forests.

Before drainage, the greater part of the bog was of medium passability, and only in the southern part, where the peat thickness reached 2 meters, was the bog difficult to traverse. Here, during excavation of soil from the main canal, excavators worked on sledges.

By type, the bog is raised and transitional.

The main cause of bog formation is the excess of precipitation over evaporation and slope feeding, i.e., the inflow of water from neighboring

territory. According to thirty-year observations, 450–490 mm fall here annually, with evaporation of about 300 mm per year. The swamping of the locality was also promoted by such factors as the negligibly small filtration coefficient of the underlying rocks and insufficient surface runoff.

Groundwater was not found in any of the 10 boreholes drilled during the surveys.

Proceeding from the soil conditions of the drainage area and the causes of swamping, the designed hydromeliorative measures are aimed at regulating surface runoff by constructing an open drainage system consisting of enclosing, conducting, and regulating networks in combination with agromeliorative measures.

The conducting drainage network is represented by main canals and transporting collectors. The total length of the canals of the conducting network is 11.4 km.

The cross section of all canals is adopted as trapezoidal, with side slopes of 1.5:1. The dimensions of the cross section of the main canals and the upland canal are determined by hydraulic calculation; the cross section of the transporting collectors is adopted structurally, with a bottom width of 0.4 m. The total length of all canals of the drainage network is 43.8 km. The main canals are constructed with a bottom gradient from 0.0004 to 0.0006. The volume of soil excavation from the canals is 192 thousand m³.

The drained part of the bog is protected from the inflow of surface waters from the adjacent territory by upland canals and the upper (in the direction of flow) parts of the canals of the regulating network, laid out in the locality in such a way that the gap between the enclosing canals in plan is no more than 50 meters.

Hydrological calculations determined the surface-runoff moduli for the following periods: the spring flood—10% probability, summer high waters—5% and 25% probability. The ordinary runoff modulus is adopted according to the Technical Conditions and Design Standards.

The initial data for the hydrological calculations are the observation data of hydrometeorological stations for a period of 24 years.

The design runoff modulus is determined by the formula of Academician A. N. Kostyakov [1]

\[ q=\frac{2.8\cdot\sigma p}{t}\cdot\frac{\kappa}{\sqrt[x]{F}}+q_0,\ \text{l/sec/ha}, \]

where \(\sigma\) is the runoff coefficient, determined mainly by the degree of absorption of water by the soil and depending on the slope of the surface of the catchment area;

\(p\) is the daily amount of precipitation or snowmelt in mm for the design period;

\(t\) is the duration of precipitation or snowmelt in hours;

\(\kappa\) is a coefficient characterizing the shape of the runoff hydrograph, whose average value is 2.0;

\(F\) is the catchment area in ha;

\(x\) is the root exponent, determined from Table 43 of the Hydraulic Engineer–Meliorator’s Handbook [2];

\(q_0\) is groundwater runoff, whose value is taken from 0.002 to 0.05 l/sec/ha, depending on the district and the nature of subsurface recharge.

The hydraulic calculations were made according to the well-known Chezy formulas.

The distance between canals was taken as an average of 300 m. Main canals, upland canals, and part of the regulating network were made with E-352, E-652, and E-653 excavators equipped with a backhoe and a “Dragline” bucket.

From the experience of draining the Shegaro-Iksa bog, it may be concluded that the “Dragline” bucket forms the slopes of canals more evenly than excavators equipped with a backhoe. In Fig. 1, the main canal M-II was made by a “Dragline.”

After the project for draining the bog had been drawn up, the Gusevo machine-reclamation station, which was carrying out the drainage work, received two new KFN-1200 rotary canal diggers. This is a fundamentally new mechanism intended for constructing a shallow drainage network. The working organs are two cutters 2800 cm in diameter, which, as it were, “saw” the soil out of the canal and, by centrifugal force, scatter it to the sides of the canal up to 15 meters.

After the canal digger passes, a canal remains that is finished completely, without any further reworking or leveling of the excavated soil (Fig. 2).

Leveling of spoil banks along canals made by excavators was carried out with a bulldozer. Roads were graded with a grader. Two bridges were built across the main canals. The bridges are wooden, single-span, on piles.

To prevent the drained peatlands from drying out, the project provides for two control gates. The control gates have not yet been built.

At the request of the collective farm and according to the approved design assignment, the drained bog is to be used for sowing perennial grasses.

A soil survey revealed five soil varieties on the drained bog: 1) peat soils—the peat layer is more than 70 cm; 2) peat-bog soils—the peat layer is from 70 to 50 cm; 3) peaty-bog soils—the peat layer is up to 25 cm; 4) humus-bog soils—the peat layer is up to 15 cm; 5) light-gray gleyed soils on elevated, non-boggy areas.

Peaty-bog and peat-bog soils are the most widespread. A smaller area is occupied by peat soils, and an insignificant area by light-gray gleyed soils.

In their natural state these soils possess a number of poor properties that limit the agricultural use of the massif. Above all, the soils have a small reserve of nutrients and an acid reaction unfavorable for plants (pH = 3.9–4.2).

According to the data of physicochemical analysis, it is necessary first of all to apply potash and phosphate fertilizers to the soil. The use of organic fertilizers in the form of manure is necessary for biological inoculation.

Liming of the acid soils is necessary for neutralization. Lime is necessary as a nutrient element for plants. The drainage of the bog has been completed.

The second task remains to be carried out—the development of the drained bog for arable land.

In the autumn of 1965, 264 hectares were plowed on the Shegaro-Iksa bog. For 1966, the work plan of the Tomsk Agrochemical Laboratory included experiments on the application of various fertilizers.

The Department of Botany of Tomsk State University developed a scheme of field experiments for placing various agricultural crops on the drained bog.

Fig. 1. The second main canal, made with a “Dragline” bucket
(author’s photograph)

Fig. 2. KFN-1200 rotary mounted ditcher at work.
Ditch depth 1.2 m, slopes one-to-one (author’s photograph)

According to the work plan of the Gusevka MMS, another 300 hectares are to be plowed in 1966.

The total estimated cost of drainage works is 123 thousand rubles. The net area is 940 ha. The cost of the works, allocated per 1 ha net, including drainage and cultural-technical works, is 131 rubles. If all agronomic requirements are observed, these expenditures can pay for themselves in 2–3 years.

In addition to the Shegaro-Iksa bog, the Gusevka machine-reclamation station of the Water Management Department of the Tomsk Regional Executive Committee is working on the Chagino bog in the same Krivosheino district. At present, a main canal 2 km long has been completed there. The work will be continued in the summer of 1966.

The preparation of design documentation for the drainage of the “Verkhnii Lug” bog in Zyryanka district has been completed. Drainage work on the “Verkhnii Lug” bog will be carried out in 1966 by the Cherdat MMS.

The Chagino and “Verkhnii Lug” bogs are lowland bogs; they are located in river floodplains and are flooded during spring high waters.

At the request of the farms, these bogs are to be used as artificial hayfields.

Lowland bogs are the best drainage sites for their use in agriculture, since the peatlands of lowland bogs are richer in nutrients and have a neutral or slightly acid reaction. Unfortunately, there is as yet no completed experience in Tomsk Oblast with the use of drained bogs in agriculture.

At the first drainage site, the Shegaro-Iksa bog, work began in the spring of 1964 and is to be completed by the end of 1967.

The experience of reclamation work in the western regions of our country can be used only in earthwork and cultural-technical operations and in the organization of work.

Questions of reclamation, including hydrological calculations, the layout of the drainage network on the plan, and the use of closed drainage, remain the subject of study in the very near future.

Only experiments carried out on our drained bogs can clarify the questions of the most rational placement of agricultural crops and the application of fertilizers, so that the enormous funds invested in reclamation measures may be used in a fully substantiated way and so that every hectare of “waste” land will yield income to the state.

LITERATURE

1. A. N. Kostyakov. Fundamentals of Land Reclamation. Moscow, Selkhozizdat, p. 473, 1960.
2. Handbook for the Hydraulic Engineer–Reclamation Specialist. Moscow, Selkhozizdat, p. 148, 1958.