Tver Region Research Articles

Influence of agromelioration and drainage methods on the field crops productivity

The effectiveness of ameliorative strip loosening to a depth of 50-60 cm and volumetric soil slotting to 45-50 cm, their influence on the productivity of field crops and agrophysical properties of drained soils with different ameliorative systems (interdrainage distance of 18 and 28 m) was studied. The experiment was carried out in the period 2015-2021. at the Gubino agricultural polygon of the All-Russian Research Institute of Reclaimed Lands (Tver Region). The soil is soddy-podzolic cultivated light loamy gleyic, drained by closed pottery drainage, formed on a moraine. Volumetric slotting was carried out with a specially designed tool with filling the subarable part of the slot with crushed straw and plant residues mixed with a humus layer. Ameliorative loosening (MR) was carried out with a converted chisel plow. The pitch of slotting and MP is 140 cm. According to the generalized data, the best results on both drainage systems were obtained in the variant with volume slotting. Ameliorative loosening increased the yield of grain crops, on average over 5 years, by 0.60 t/ha (17.0%) and 0.79 t/ha (20.7%), slotting by 0.90 and 1.02 t/ha ha (25.6 and 26.7%), respectively. Additional grain harvest for the five-year period of MR action on the estimated drainage was 3.0, on sparse - 3.95 t/ha, and with volumetric slotting of the soil - 4.5 and 5.1 t/ha, respectively. On spring rapeseed, the best results were also obtained in the variant with sparse drainage and volumetric slotting of the soil. The increase in the yield of green mass in this variant, on average over 3 years, amounted to 3.6 t/ha of green mass, or 19.0%. It has been established that on soddy-podzolic light loamy gleyic soils with an atmospheric type of water supply, when designing ameliorative systems for field crop rotations, it is possible to use drainage systems with extended, compared to the calculated, interdrainage distances, which helps to reduce the cost of drainage. The use of land reclamation techniques increases the efficiency of sparse drainage.

Features of the soil aciditification dynamics in agricultural landscape

The results of long-term monitoring of the spatial dynamics of soil acidification within the terminal moraine hill are presented. The studies were carried out in 1996-2020. on the agro-ecological transect (VNIIMZ, Tver region) - an array crossing the landscape positions of the hill, consisting of 10 fields with an individual history. The exchangeable acidity of soils was determined at 30 sampling points, regularly located in each field at 40 m from each other. We used pHKCl data for 1996 and 2020 and acidification indicators determined as the difference in the values of soil exchange acidity at the beginning and end of observations. Statistical processing consisted in revealing the influence of anthropogenic and natural factors on soil acidification. It was found that the soils were significantly acidified during extensive farming. In 1996-2020 the average exchangeable acidity decreased by 0.6 (0.023 per year), but the soils did not move out of the slightly acidic category, which will take another 10 years. The spatial variability of pH significantly decreased: strongly acidic and neutral soils disappeared from the soil cover. It has been established that the landscape determines 34% of the spatial variability of soil acidification, and anthropogenic factors determine 26%. There are 4 groups of territories in the agrolandscape, significantly differing in the degree of soil acidification, which is explained by the heterogeneity of the relief and parent rocks. According to the diversity of anthropogenic impact, 5 groups of fields are distinguished, where differences in soil acidification are due to their history. In general, it is impossible to single out an anthropogenic factor in the agrolandscape that significantly affects the degree of soil acidification, however, the impact is noticeable on individual substowlands, which allows developing measures to reduce the intensity of this degradation factor. It is recommended to develop crop rotations within the tops of the hills and not to place fallows, hayfields and hatching fields with eastern goat's rue. On the middle, lower parts of the slopes and in inter-hill depressions, it is not recommended to place winter and cover crops.

Использование жиров различного происхождения в комбикормах для бройлеров

Purpose. Determination of the effectiveness of using fats of various origins in compound feed for broiler chickens. Materials and Мethods. A scientific and economic experiment was carried out on 4 groups of broiler chickens of the Cobb-500 cross at the Verkhnevolzhskaya Poultry Farm (Russia, Tver region). The poultry-rearing period was 37 days. Broilers in the control group received the main diet according to the growing phases; for chickens in the experimental groups, part of the sunflower oil in the diet was replaced with animal feed fat "Olisa": in group 2 – 0.5% in CCF Rost, 1.0% in Finish-1 and Finish- 2; in group 3 – 1.0% in CCF Rost, 1.5% in Finish-1 and Finish-2; in group 4 – 1.5% in CCF Rost, 2.0% in Finish-1 and Finish-2. The dynamics of live weight were recorded by weekly control weighing of broiler chickens. The safety of the poultry population was determined by counting dead birds. The absolute and average daily gain in live weight, the cost of feed per 1 kg of gain in live weight, the productivity index and other indicators were also determined during the growing process. Results. The introduction of 1.5% animal feed fat “Olisa” into the compound feed instead of part of the sunflower oil in CCF Rost and 2.0% in Finish-1 and Finish-2 contributed to an increase in both the average daily and absolute gain in live weight. The latter indicator was higher in broiler chickens of the fourth experimental group by 8.6% compared to the control group. Poultry from the same group had a higher meat yield per 1 m2 of floor area. Their productivity index was higher than in the control group by 6.6%. At the same time, the safety of poultry population in all groups participating in the experiment was high. Conclusion. Replacing part of the sunflower oil in feed with animal fat in the optimal dosage contributes to obtain high live weight, daily gain, safety of broiler chickens and productivity index.

The usage of silicon-humic preparations in the potato cultivation

One of the ways to increase crop yields is the use of foliar treatments with humic preparations. The purpose of the research is to study the effect of silica-humic preparations on the yield of potatoes and changes in soil characteristics. In the experiment, the effect of the humic preparation BoGum and the silicic-humic preparations BoGum-S and nanoBoGum-S obtained on its basis on the yield of potatoes of the Skarb variety and the agrochemical parameters of the soil was studied. The experiment was carried out on soddy-podzolic soil in 2020-2022. at the Gubino VNIIMZ agricultural polygon in the Tver region. The preparations were used for the treatment of tubers and double foliar feeding of vegetative potato plants. Background - mineral fertilizers (N65P65K65). It was shown that all preparations contributed to the increase in the yield of potato tubers, mainly due to an increase in the mass of marketable tubers. The increase in potato yield from the use of BoGum and BoGum-S was almost the same and averaged 4.5% over three years, the use of nanosized nanoBoGum-S gave an increase of 10.6%. The years of research were distinguished by unfavorable weather conditions (2020 - excessively humid, 2021 - dry, 2022 - slightly dry). The increase in potato yield showed that the preparations reduced the impact of unfavorable abiotic factors. In the flowering phase of potatoes, a decrease in the content of monosilicic acids and an increase in polysilicic acids in the soil were noted in the variants with the use of silicic preparations compared with the control. In addition, when using all preparations, the accumulation of mobile phosphorus in the soil was observed on average by 9-19 mg/kg of soil.

Spectral reflectance of atmospheric dust as an indirect indicator of its soil origin

Atmospheric dust affects both human health and climate change. Therefore, the study of atmospheric dust is one of the important tasks of many scientific fields. The aim of our research was to indirectly assess the relation of atmospheric dust over arable lands of two test sites in Tver and Tula regions of Russia with soils. Dust was analyzed on aspirator filters after pumping specified volumes of air at the level of 20–30 cm above the arable surface. Its spectral reflectance was used as a criterion of soil origin of dust, which was compared with the reflectance of the size fraction (50–200 nm) of soils isolated by dry sieving of a sample of arable soil horizon. The spectral reflectance of dust was calculated based on approaches of linear separation of spectral mixture, taking into account the projective coverage of dust particles on filters, which was determined by analyzing microscope photographs of the filters in GIS. As a result, it was found that the recovered dust spectra on the filters correlate well with the spectra of the same size soil fraction separated by dry sieving, which indirectly confirms the predominance of specifically soil dust on the filters. Spearman correlation coefficient is within the range of 0.84–0.90, Kendall's Tau correlation coefficient varies within 0.70–0.79 (at significance level p < 0.05). Under the conditions of insignificant atmospheric dust load and when collecting a sufficient amount of dust for direct analysis is time and labour consuming, the approach used may serve as an alternative for indirect confirmation of the soil origin of dust in the near ground layer of the atmosphere. In the future, this approach can be used as a basis for monitoring of arable soils deflation.

Assessment of water quality of Shlinsky reservoir by hydrochemical indicators

The paper presents the main results of assessing the water quality of the Shlinsky reservoir for the period 2015-2019. Based on the analysis of hydrochemical data obtained by standard chemical methods, according to 22 indicators. Monitoring of the reservoir water quality until 2021 was carried out by the Dubna Ecoanalytic Laboratory. The Shlinsky reservoir is located on the border of the Tver and Novgorod regions, is part of the Vyshnevolotsk water system. The reservoir provides releases for the needs of energy, water transport and improvement of water supply in Moscow. As a result of the study, priority pollutants were identified, the water quality of the reservoir was assessed based on the results of calculating the water pollution index (WPI) and the specific combinatorial index of water pollution (SCIWP). It is shown that there is no significant anthropogenic impact on the ecosystem of a water body. The water quality of the reservoir is assessed as "moderately polluted" water (according to the value of the water pollution index) and slightly polluted - polluted water (according to the value of the specific combinatorial index of water pollution).

The content of photosynthetic pigments in thallomas of Parmelia sulcata Taylor in recreational areas of the city of Tver and the Spirovsky district of the Tver region

To date, the assessment of the qualitative and quantitative content of assimilating pigments in lichen thallomas is one of the most common indicators for identifying the degree of damage to these organisms in conditions of environmental pollution. The aim of the work is to assess the content of photosynthetic pigments (chlorophyll a and b) in the thallus of Parmelia sulcata Taylor lichen in the ecosystems of Tver and the Spirovsky district of the Tver region with varying degrees of anthropogenic transformation. The study of the pigment content in the samples of lichen P. sulcata collected in the recreational areas of the city of Tver and the village of Spirovo with different levels of anthropogenic transformation and pollution. Significant differences in the content of chlorophylls a and b were found, which indicates a high plasticity of the photosynthetic system. The level of Cl a content in recreational areas is higher than in background conditions. The high variability of the values of the concentrations of Cl b indicates the priority value of the pigment system during adaptation.

Biologically active substances in blueberry shoots (Vaccinium myrtillus L.) of Russian origin

In the current study composition of phenolic compounds of common bilberry shoots (Vaccinium myrtillus L.) from the Russian Federation was determined. The presence of arbutin, rutin, tannin, and gallic acid in crude herbal drugs was confirmed by thin-layer chromatography and high-performance liquid chromatography with ultraviolet detection. A quantitative analysis of these substances in common bilberry shoots, harvested in the Bryansk and Vladimir regions in 2016-2017, and the Tver region in 2017 showed similar results. The obtained data can be used in the comparative study of the metabolome of medicinal plant, the development of regulatory documentation for common bilberry shoots. It is shown, that common bilberry shoots have antiradical, membrane stabilizing, antioxidant, and antitoxic activity.

Diversity and Functional Potential of Prokaryotic Communities in Depth Profile of Boreo-Nemoral Minerotrophic Pine Swamp (European Russia)

Natural peatlands represent a wide range of habitats that contribute to the conservation of biodiversity, including microbial biodiversity. Molecular biological methods make it possible to significantly increase the accounting of microbial diversity compared to the cultivation methods. The studies on microbial diversity in minerotrophic peatlands using molecular biological methods lag significantly behind such studies for ombrotrophic peatlands. In this work, we characterized the taxonomic composition and functional potential of the prokaryotic community of the minerotrophic pine swamp (fen) in the Tver region of northwestern Russia using high-throughput sequencing of 16S rRNA gene fragments. This study is unique, since it was carried out not in individual horizons but across the entire fen profile, taking into account the differentiation of the profile into the acrotelm and catotelm. The composition and dominants of bacterial and archaeal communities were determined not only at the level of phyla but also at the level of classes, families, and cultivated genera. The prokaryotic community of the studied fen was shown to have a high taxonomic diversity (28 bacterial and 10 archaeal phyla were identified). The profile differentiation of the taxonomic composition of prokaryotic communities is most clearly manifested in the analysis of the acrotelm and catotelm. In the bacterial communities of the acrotelm, the top three phyla included Acidobacteriota, Alphaproteobacteria, and Actinomycetota, in the catotelm—Betaproteobacteria, Bacteroidota, and Chloroflexota. In archaeal communities of the acrotelm, we discovered the monodominance of Nitrososphaerota, in the catotelm—the dominance of Bathyarchaeota and subdominance of Thermoplasmatota, Halobacterota, and Aenigmarchaeota. The hot spots of microbial diversity in the studied fen profile were found to be the 0–20 cm layer of the acrotelm and the 150–200 cm layer of the catotelm. In contrast to the taxonomic composition, the functional profiles of the prokaryotic communities of the acrotelm and catotelm were generally similar, except for methane metabolism, which was primarily carried out in the catotelm.

Оценка психологического статуса и особенностей поведения мировых судей в практике примирения

The article presents the results of a psychodiagnostic study (2022) to assess the psychological status and behaviour of magistrates engaged in the reconciliation practice in Tver and the Tver region. They actualize the problem of popularizing the reconciliation practice to settle a judicial dispute, and also substantiate the psychological status of a justice of the peace as the main figure in the reconciliation process. They also raise the question of the justice of the peace’s personal and psychological resources and his or her compliance with their professional competencies.

The effect of weather and landscape conditions on productivity of the spring wheat variety ‘Zlata’

The current study was carried out in 2010–2022 to determine the effect of weather and landscape conditions on productivity of spring wheat (Triticumaestivum) in a stationary field trial located on a drained soddy-podzolic soil within a terminal moraine hill in the Tver region (ARRIMS). The object was drained by closed pottery drainage. The distance between drains in different agricultural landscapes was 40, 30 and 20 m. In the trial there was a grain-grass crop rotation (oats+grasses – grasses of 1–2 years – winter rye – spring wheat). The crop cultivation was carried out according to extensive technology. The years of different humidity were factor A; factor B was the type of agromicrolandscape, factor C was the type of soil. There has been studied the moisture supply and temperature regime of the soil, spring wheat productivity in various agricultural landscapes. There has been established that the maximum productivity of the spring wheat variety ‘Zlata’ (2.17 t/ha) was obtained in the optimal years for the growth and plant development. In dry years, the value of this indicator decreased by 49–70 % and 51–73 % compared with excessively wet and optimal years, respectively. The variability of wheat productivity raised in dry years to 26 % and decreased to 14.5 % in optimal and excessively wet years. During the period of 2010–2022 the maximum wheat productivity (2.25 t/ha) was obtained in the transit-accumulation variant of the northern slope, its increase was 0.4 t/ha compared to the average for the trial. In years of different moisture availability, there was studied a correlation between spring wheat productivity and various soil parameters. There was obtained a direct correlation dependence of productivity in dry years with the amount of productive moisture (r = 0.70) and with the biological activity of the soil (r = 0.49); an inverse correlation was obtained in excessively wet years with aeration porosity (r = –0.66) and biological activity of the soil (r = –0.55).

Structural Features of Pine Catena Stands: from Forest to Oligotrophic Bog

The article presents the results of studies of the pine catena’s stands structure, conducted in the Zapadnodvinsky forestry of the Tver region (Zapadnodvinsky forest-swamp station of the Institute of Forest Science of the RAS, IFS RAS), linking the biogeocenosis of the forest and swamp parts of the oligotrophic bog. The purpose of the research is to study the forestry characteristics, morphometric indices, origin, age structure, dynamic processes and volume indicators of pine stands during the transition of the forest part of the catena to the oligotrophic bog. The pine catena includes four sections with a total length of 110 m and a width of 40 m: the upper forest automorphous zone (PP 1), the slope transit zone (PP 2 and 3) and accumulative zone (PP 4) with forest types changing from cranberry-blueberry pine woods of II quality class to shrub-sphagnum meso-oligotrophic pine woods on 6 m of peat (V quality class), underlain by organic lake sediments. The age structure of stands varies from the conditional evenly-aged restorative dynamics in the forest part to the highly-unevenly-aged dynamics found closer to the climax phase of the meso-oligotrophic sphagnum swamp. The forest part is characterized by the better condition indicators’ values, while the oligotrophic bog’s stands have the worst ones. The pine biogeocenosis of an oligotrophic sphagnum bog is close in dynamic characteristics to sustainable climax forest communities with a maximum age of the first generations trees of approximately 240–280 years. The stands condition along the catena profile varies from healthy in the forest part to the weakened with the degradation development dynamics in the accumulative part of the sphagnum bog.

Оценка окислительно–восстановительных реакций донных отложений пруда Угольчик методом автографии на фотобумаге

The article considers the analysis of bottom sediments selected on the territory of the Central Forest State Natural Biosphere Reserve of the Tver region, in the Ugolchik Pond for the assessment of redox reactions by autography on photo paper, which is an indicator of the state and number of anaerobic microorganisms at the bottom of the reservoir according to autography. Keywords: BOTTOM SEDIMENTS, AUTOGRAPH ON PHOTO PAPER, AQUATIC ECOSYSTEMS, ECOLOGICAL ASSESSMENT OF WATER BODIES

Experimental statistical analysis of radar signals reflected from weather hazards

The nature of the causes of prerequisites for flight accidents due to meteorological conditions has remained unchanged for many years. For the effective operation of aviation, it is necessary to solve the issues of the timely detection of weather hazards and the identification of their intensity. This article discusses the research into the atmospheric reflectivity and turbulence in cumulonimbus clouds using a near-field meteorological radar system. Experimental studies are carried out with the aim of obtaining estimates of statistical characteristics of the reflectivity distribution and turbulence for weather hazards. The methodology for conducting an experimental study to obtain information about the weather hazards (rain shower, thunderstorm and hail), special features of the radar reflectivity propagation and the specific rate of turbulent energy dissipation in the considered conditions for the Tver region is presented. The analysis of the obtained results has been carried out: comparisons of meteorological data derived, using the meteorological radar complex of the near airfield zone (WR BZ), with the reliable sources of meteorological observation data obtained during experimental studies. Studies of horizontal sections and vertical profiles of the weather hazards parameters under consideration, associated with the cumulonimbus area, have been carried out. A data bank has been formed. Histograms of the information parameter distribution have been constructed. The article considers the results of experimental data approximation, using the χ2 criterion for various distribution laws. It is shown that the distributions of reflectivity and turbulence can be described by the generalized Rice’s law. The results obtained can be used to correct the classification criteria of weather hazards to subsequently increase the justification and reliability of the weather hazard classification. The further development of the method to process meteorological information is also of paramount importance to more correctly interpretate experimental data processing results of remote meteorological phenomena sensing.

Agromeliorative treatment of drained soils

The paper shows efficiency of volumetric slotting, methods of basic treatment and their combined effect on the performance of field crops and agrophysical properties of drained soils. The experiments were carried out at the Gubino experimental agro-polygon of the All-Russian Research Institute of Reclaimed Lands (VNIIMZ), located at the reclamation facility in the Tver region. The soils under experiment are cultivated soddy-podzolic, light loamy gleyic, formed on a thin binomial, drained by closed pottery drainage method. Volumetric slotting was carried out to a depth of 45–50 cm with filling the subarable part (30–50 cm) with crushed straw, plant residues mixed with a humus layer. The slotting was carried out with a specially designed tool. Slot width – 16 cm, slotting pitch – 140 cm. Efficiency of ridge plowing, volumetric slotting of the soil and their joint action has been determined. The yield of oats during ridge plowing increased by an average of 0.36 t/ha (12.0 %) over 5 years, in case of slotting – by 0.60 (20.0 %), in case of combined action – by 0.82 t/ha, or 27.0 %. The share of slotting in the total increase in yield on average over 5 years was 73.2 %, ridge plowing – 26.8 %. The positive effect of slotting on the yield of field crops during the experiment was observed for 6 years. The total increase in yield from volumetric soil slotting on oats for 5 years was 3.0 tons of grain per 1 ha, with combined action with ridge plowing – 4.1 tons of grain per 1 ha, or 36.7 % higher. The increase in the yield of oats, both with soil slotting and with ridge plowing, occurred due to an increase in the number of productive stems and the mass of grain in the panicle. With slotting, these indicators increased by 8.4 and 11.3 %, with ridge plowing – by 6.1 and 12.0 %. The results of the research can be used in the development of agro-reclamation tillage systems and in adaptive agricultural technologies for the cultivation of spring grain crops.

Peculiarities of propagation of varietal admixture of oilseed flax in sparse crops of fiber flax in the conditions of the North-Western region of the Russian Federation

Relevance. In course of the varietal identification of fiber flax seeds lots produced in research institutions of the Russian Federation, plants atypical for the varieties tested were periodically identified. Their belonging to a mechanical varietal impurity (rogue) was confirmed, in some cases, by the results of the progeny check. The purpose of the work is to clarify the indicator of varietal purity of flax seeds of the categories «original seeds» (OS) and «elite seeds» (ES) in GOST R 52325-2005.Methods. Trials were carried out on sod-podzolic medium loamy soil in the Tver region. The study objects included seeds and plants of brown seed fiber flax variety Antey (control) and yellow-seed variety of oilseed flax LM 98 (rogue). The area of the accounting plot is 1 m2. Seeding rates are from 5 to 12 million seeds per 1 ha (depending on reproduction).Results. It was found that varietal contamination of flax seeds with rogue in the amount of 0.2–1% did not affect the yield of flax products. In the process of seed reproduction in crops of the OS category, the content of impurity seeds increased by 0.1%, 0.2% and 1% with initial clogging — by 0.2%, 0.4%, 0.7% and 1%. In other variants, it remained at the level of the initial blockage. In the crops of the ES category, a significant increase in the amount of impurity seeds (from 0.5 to 0.9%) was noted, except for the variant with initial clogging (0.2%), where its content remained at the initial level. Based on the research results, it was proposed to reduce the varietal purity of flax seeds in GOST R 52325-2005 for the category «OS» to 99.7%, «ES» — to 99%.

The content and composition of organic matter of sod-podzolic soil when applying fertilizer mixtures based on sewage sludge

Relevance. The organic matter of the soils of the Non-Chernozem zone requires additional sources of its replenishment, which can include sewage sludge (SS). The paper investigates the use of sewage sludge from Tver, introduced fresh into a mixture with additional organic substrates (sawdust, peat, straw) in the field crop rotation link.Methods. The experiment was carried out in the Tver region on sod-podzolic sandy loam soil in fourfold repetition. OSV was introduced as part of a total dose of a fertilizer mixture of 60 t/ha with additional organic substrates (sawdust, peat, straw) taken in different proportions (1:1, 1:2, 1:3) at the beginning of the experiment. The area of the experimental plot is 6 m2. Crops of the crop rotation link — mixture vetch and oat, winter rye, spring barley. The content of organic matter, its group and fractional composition were determined in soil samples according to the methods generally accepted in agrochemistry.Results. The introduction of SS together with additional substrates contributed to an increase in the amount of soil organic matter (1,38–1,5%) and its maintenance in the aftereffect at the level of 1,33–1,49%, in the control variant this indicator was 1,26% (the significance of differences p < 0,05). The studied fertilizers provided an increase in the share of GA-1 and a decrease in FA-1a. In comparison with the finished compost, fertilizer mixtures, in which the components were in equal proportions, were ahead of the comparison options in their effect. They also contributed to the highest increase in productivity of the crop rotation link among all the variants of the experiment (an increase in control — 61,1–68,2%). Compost provided an increase in productivity by only 37,9%.

FEASIBILITY OF USING THE GENE POOL OF THE SYCHEVSKAYA BREED TO IMPROVE SIMMENTAL DAIRY CATTLE IN SIBERIA

The research results into the history of the Siberian zonal type of Simmental cattle creation are reflected. It has been established that the leading role in its formation was played by the Smolensk region’s Simmental cattle, which in 1950 was registered as a Sychevskaya breed. Bulls of Swiss, German and Austrian breeding were also used. Since the mid-80s. 20th century to increase milk productivity and suitability for industrial technology, Siberian herds of semimetals were actively crossed with bulls of the Holstein breed (red-and-white colour), and since the beginning of the 21st century. Producers of Austrian and German origin are widely used, which has led to a significant increase in milk productivity, quality indicators of milk and live weight of animals. As a result, domestic lines are practically not found in the Simmental herds of Siberia. Accordingly, the valuable adaptive qualities necessary for dairy cattle breeding in areas with highly natural and climatic conditions were partly lost. Many of the cows began to deviate towards the meat and dairy type, which harmed milk productivity. The gene pool of the domestic Simmental of the desired dairy and milk-meat type has been preserved only in the form of the Sychevskaya breed in the Smolensk, Tver and Kaluga regions. Data on the current state of the number of livestock, genealogical structure and productive indicators of the Sychevskaya breed are presented. The Sychevskaya breed is superior to the Simmental breed in terms of the mass fraction of fat and protein in milk, the yield of calves, the duration of the dry period, the product of meat from a cow, the number of heifers for breeding sales per 1 cow, which provides it with a higher efficiency rating. The expediency of using bulls of the Sychevskaya breed for selection and breeding work with herds of Simmentals in areas with highly natural and climatic conditions in farms with low food supply, specialising in milk production, is substantiated.

Регрессионные модели смешанных эффектов зависимости высоты от диаметра ствола в сосновых древостоях европейской части России

Evaluation of the relationship between tree heights and diameters in the course of logging sites can be done through the use of tables of height categories or regression models. Models of mixed effects make it possible to improve the accuracy of forest inventory to a large extent. The purpose of the study is to develop a mixed effects model for describing the dependence of heights on the diameters of pine trees in the European part of Russia. In the course of study we used the data from measurements of 3 571 model pine trees growing on 201 trial plots from 13 regions of the European part of Russia from Karelia to the Samara region and from the Tver region to the Komi Republic. The paper analyzes 28 simple regression models of the dependence of height on diameter, selected according to literary sources. The selection of the best models was based on quality metrics accepted in statistics, such as the square root of the root mean square error (RMSE), the average percentage of absolute error (MAPE), the average absolute error (MAE), bias (Bias), coefficient of determination (R2), information criteria Akaike (AIC) and Bayesian (BIC). The two-parameter Neslund equation is recognized as the most simple and universal among the fixed effects models. To increase the predictive power of the Neslund equation, a separate trial plot was added as a random effect, which made it possible to significantly improve the quality metrics. It has been established that the height curves predicted by the obtained model are flexible and have a significant response to the initial ratios of the height and diameter of individual trees. The resulting model of mixed effects is an alternative to the tables of height categories used in the practice of forest accounting, which show only conditional relationships between the heights and diameters of trees. The introduction of industry standards developed on the basis of the model will improve the efficiency of accounting for wood resources in pine forests in the European part of Russia.

Ярославские традиции в церковной стенописи Тверского края эпохи классицизма

In the article an attempt is made of clearing up the source of the North-East Tver region artistic culture flourishing in the 19th century that especially became strikingly apparent in church wall-painting. Beginning with the early 19th century the painters from the city of Yaroslavl were actively working in the Tver region and introduced various traditions of Yaroslavl into the fine arts. One of the characteristic features of the Yaroslavl painters’ language was the combination of Old Russian and West European devices in the classicism stylistic context that found a reflection in the Tver region monuments. At present the phenomenon of different trends coexistence in the beginning of the 19th century is well known in the specialized literature through the example of icon-painting. A similar occurrence took place in the monumental art but so far it hasn’t been investigated in the scholarly literature. The works of the Yaroslavl painters Banshchikov and Smirnov are preserved in the Resurrection cathedral in Kashin as a masterpiece of wall-painting without renovations or restorations. Through the example of the cathedral paintings the devices of the Yaroslavl painters are being analyzed, in particular the use of the rare Old Testament cycle in the painting programme created on the basis of the popular German engravings from Christoph Weigel Bible (1695). A comparison of the Yaroslavl painters’ style in the Korsun Icon of the Mother of God church in the village of Zelentsovo and a number of the North-East Tver region murals is carried out. The analysis of the interregional connections and the study of the Old Russian traditions firmness in the classicism period favour the deepening one’s knowledge about the view of the Russian art development in the first half of the 19th century. For the Yaroslavl region bordering the Tver region districts Yaroslavl as a strong monumental art centre became one of the main sources of the new artistic traditions.