The composition and structure of land resources and drained land resources of the Republic of Belarus are analyzed by types of land and by regions. The volumes of urgent repair and maintenance work in the country are given and an analysis of the technical condition of land reclamation systems is given. The tasks of subprogram «Engineering antiflood measures» and subprogram «Development of land reclamation for agricultural purposes» of the State program «Agrarian business» for 2021–2025 are outlined.

The article provides data on the types of drainage geocomposites currently used in road and industrial construction, their conditions of use and technical characteristics of some of them. There is practically no information about the filtration and hydraulic characteristics of geocomposites. Data are given on the results of laboratory studies of the water intake capacity of model absorption columns using 10 types of drainage geocomposites. There is a significant influence of geocomposites on increasing the water intake capacity of the absorption columns. The developed design of the experimental absorber column using a drainage geocomposite and a polymer shaped membrane is presented. The validity and expediency of such a design is confirmed by the data of the drainage test at the test site to study the effect of the wall filter effect on the water intake capacity of drainage.

The assessment of the accuracy of calculating water consumption (total evaporation, evapotranspiration) of sugar beet using the bioclimatic method was carried out according to the bioclimatic coefficients calculated by the formulas of A. M. and S. M. Alpatiev, A. I. Mikhaltsevich and TKP-45.304-178-2009 (02250), as well as by biothermal coefficients calculated from the average daily and maximum daily air temperatures. It was found that when using in water balance calculations the bioclimatic coefficients of sugar beet obtained from the formula of A. M. and S. M. Alpatiev, big errors are possible in determining water consumption (more than 50 %). Averaging over many years of the numerical values of the bioclimatic coefficients of sugar beet, obtained using the formulas of A. I. Mikhaltsevich and TKP-45.304- 178-2009 (02250), does not lead to such large errors. The use of sugar beet biothermal coefficients in water balance calculations, calculated from average daily and maximum temperatures, gives the most accurate resultsl.

Lathyrus sylvestris L. Zhuravushka in a mixture with meadow timothy on peat soil provided an average yield of 358–395 c/ha of green mass or 72.4–79.7 c/ha of dry matter on average for three years. An increase in its seeding rate from 15 kg/ha (0.4 million seeds/ha) to 25 kg/ha (0.7 million seeds / ha) had little effect on the overall yield of the herbage, but increased its safety in the herbage. The Lathyrus sylvestris L. reached its maximum development at 3–4 years of life and its share in the harvest of grass with timothy meadow in the third mowing was 34.8 %. With an increase in the age of the herbage and the seeding rate of the rank, there is a tendency to increase the share of the rank in the crop to 34.8 %. The index of coenotic activity of Lathyrus sylvestris L. in the herbage with timothy meadow increased during the growing season from the first mowing to the third, as well as with the age of the herbage from 0.07 in the second year of life to 0.82 in the fourth.

In 2020–2021, productivity and the nutritional value of alfalfa in single-species and mixed crops were studied on cohesive-sandy soil with an increased content of humus, phosphorus and potassium, on the basis of which it was concluded that the greatest productivity with good quality indicators of green mass is provided by the option of its spring sowing with a seeding rate of 6 million germinating seeds per 1 ha in a pea-barley mixture (0.8 million/ha + 3.0 million/ha). There may also be variants of both single-seeding of alfalfa (12 million/ha) and mixed with awnless kostretz, meadow fescue or meadow timofeevka (6 million/ha of legume and cereal components each), which showed a high collection of fodder protein units in the second year of grass life.

The results of studies on the formation and productivity of fodder agrocenoses created as a result of the joint sowing of perennial legumes and cereal grasses with oil radish are presented. It has been established that red clover and alfalfa are characterized by the highest cenotic activity in agrocenoses, which were created with the participation of oilseed radish in the amount of 70 % of the seeding rate in its pure form, which is 2.1 million viable seeds/ha. At the same time, the optimal structure for the participation of legume species in the composition of the herbage (40.3–42.5 %) is ensured by adding to the above amount of oilseed radish cereal grasses (60% of the sowing in its pure form) and red clover or alfalfa (80 % of sowing in its pure form). This sowing scheme also provides the highest levels of herbage yield – 9.20–10.20 t/ha.

The research results about sod-podzolic sandy loam soil liming on nutrient accumulation in the spring barley grain and straw are presented. The data of nutrient removing by the barley yield are showed. It is considered the nutrient balance and its intensity using dolomite flour, defecate and carbide lime ameliorant.