The purpose of a comprehensive field experiment was to evaluate the agronomic efficiency of a precise organomineral fertilizer system based on a uniform and differentiated application of mineral and organic fertilizers. The methodological basis of the study was a two-factor landscape field experiment with grain-grass crop rotation, established within the sloping agricultural landscape of a gently undulating glaciolacustrine plain. It was determined, that soil and agrochemical conditions and a stable soil water regime were of decisive importance in the effectiveness of fertilizers within the agrolandscape. The level increase in yield from the differentiated application of peat-dung compost (once in a bare fallow) and mineral fertilizers relative to the uniform application was 7–12% for winter wheat, 5–11% for oats, 3–8% for perennial grasses, and in the entire crop rotation—5–8%. It regularly decreased during the mineralization of the applied organic fertilizers. Among the three variants of the precise fertilization system studied, the best result was achieved in the option, where organic and mineral fertilizers were applied differentially. In this case, the absolute increase in crop rotation productivity relative to the unfertilized variant reached 16.39 t ha−1 of cereal units or 116%, and relative to the uniform fertilizer system—2.27 t ha−1 of cereal units or 8%.

The North-West region of Russia has an exceptional variety of climatic and landscape ecology conditions. The development of the scientific foundations of adaptive farming requires the radical restructuring of the field experiment work system. This system relies on the methodology of mathematically and physically modelling agroecosystems to develop fundamental aspects of the theory used to manage their condition, and to solve modern applied problems of adaptive farming in a promising manner. During a long-term study, the methodology of a multilevel system of field experiments in the Menkovsky branch of the Agrophysical Institute was developed and tested. Its construction was based on the principles of multiple scales and consistency. It includes field experiments on a fundamental level, called “great balance experiment”, “stationary agroecological experiment”, and “stationary agrophysical experiment”. Also, on a fundamental to applied level, landscape experiments, precision farming experiments, and cooperative experiments have been elaborated and started. On a more detailed level, comparative experiments, small-plot experiments, microfield experiments, and different experiments of contract research are included. The system is completed by large-scale production experiments and monitoring studies. The comprehensive system of experiments is basically built according to the multiscale nature of the agroecosystem’s organization and aims for a mathematically precise description of the processes and the phenomena occurring in them. Its main implementation aspect is the regulatory framework for resource-saving farming system designs.

Spatio-temporal heterogeneity of agroecological conditions is a fundamental factor of the crop production process in agricultural landscapes. A comprehensive study was launched to search for the most effective precision fertilization systems for the landscape–ecological conditions of the Chudskaya Lowland’s undulating plain, which has a soil cover of a lithogenic mosaic of sod-podzolic soils. Under production conditions in 2007, a precision soil survey of the agricultural landscape was carried out, and a landscape field experiment was laid in a vegetable crop rotation on sod-podzolic soils from sandy to medium loamy granulometric composition. The precision fertilization system based on preliminary differentiated soil cultivation provided an increase in the productivity of the vegetable crop rotation by 132% relative to the control and by 37% relative to the traditional mineral fertilization system, with a profitability of 63%. The system improved the quality of the main products of the vegetable crop rotation, increasing the content of crude protein by 19%, potassium by 32% and vitamins by 62% and decreasing the spatial variability of the most sensitive properties 1.5–2.1 times. Nitrates accumulated in potato tubers 14% less than in the variant of the uniform fertilization system, and the accumulation of starch and vitamin C increased by 6 and 24%, respectively. Against the background of unfavorable physicochemical and agrophysical states of most agricultural soils, the precision mineral fertilization system did not provide a reliable superiority of crop productivity over the traditional uniform fertilization system.

Restoring soil fertility and optimizing the agronomic state of agrolandscapes are key issues of commercial agricultural management in the zone of sod-podzolic soils. In a series of landscape ecology studies and field experiments, some phenomena were revealed and a number of regularities were established. Weather and climate risks increased for regional farming. The deterioration of the agronomic state of modern agrolandscapes is accompanied by excess growth of trees and shrubs, overmoistening and secondary waterlogging. Agrolandscapes and soil combinations form a decreasing series in terms of the degree of heterogeneity of properties of automorphic and semi-hydromorphic sod-podzolic soils: lithogenous mosaics on hilly plains > lithogenous mosaics on moraine plains > complexes on hilly plains > complexes on glacial lake and glacial outwash plains > spottiness on plains of different genesis. Improving sod-podzolic soils’ fertility to good and high levels increases the productivity of field and vegetable crop rotations 2.8–4.2 and 3.7–5.0 times, respectively. Using mono-nitrogen fertilizer systems on cultivated soils increases crop rotation productivity by 24–46% and intensifies the hidden degradation of effective soil fertility. The average annual reduction of parameters reaches 0.03–0.20 for pHKCl, 0.015–0.020% for humus content and 6–20 mg/kg and 10–80 mg/kg for mobile phosphorus and potassium, respectively. Precise fertilizer systems increase the recoupment achieved with 1 kg of NPK in vegetable crops by 18–21%, in field crops by 12–17% and in profitability by 38–49%.

The idle lands of the Non-Chernozem zone of Russia are quickly overgrown with tree and shrubby vegetation (TSV). Their active development under modern conditions needs a comprehensive justification of the available technological options for removal and processing of TSV. To evaluate their agro-economic efficiency, a comprehensive study was carried out at Sofia LLC in the Tosnensky District of the Leningrad Region. Its methodological basis was model-field and production experiments, laid out in weakly and medium-cultivated sod-podzolic gleyey soils of heavy loamy granulometric composition. They studied the agroeconomic efficiency of application of traditional ameliorants (milled raw dolomite and poultry manure supplemented with potassium fertilizer) and TSV processing products (wood chips, wood chaff, biochar and ash). The study determined the negative impact of products of TSV processing embedded in the soil on crops; the lack of a direct correlation between agroecological and economic efficiency of development technologies; an irreplaceable positive role of a complex of chemical ameliorants. The level of profitability of its use varied in experiments from 7–15 % for cultures and varieties undemanding of fertility to 48–56 % for demanding ones. On its basis, radical improvement of the soil properties was ensured, which made it possible to increase the productivity of the crop rotation link against the background of the embedded wood chips from 13.3 to 19 tons of forage units (FU) per hectare, of wood chaff – from 10.5 to 19.2 t FU/ha, biochar – from 16.1 to 21.4 t FU/ha, ash – from 15.6 to 21.2 t FU/ha while improving product quality. The profitability parameters of technologies for the development of the shrubby idle land based on the data on the cost of yield increase (21–52 %) are 8.8–9.1 times lower than for the additionally produced and sold dairy products (191–459 %). Due to our production and direct sale of high-quality dairy products, the average annual net income from the development of 1 hectare of lightly and heavily shrubby idle land increases from 21 to 205.7 thousand roubles and from 9.7 to 80.5 thousand roubles respectively. With the re-processing of TSV to Eurowood, these indicators increase by 159.2 thousand roubles/ha per year. Due to the relatively high cost of biochar production, the «biochar + complex of ameliorants» option, the best in terms of agronomic and environmental efficiency, is significantly (1.7 times) inferior to agronomically less efficient technologies in short-term studies in terms of profitability (132 % versus 230 %). Less efficient technologies include embedding of crushed TSV in the soil with modern milling machines. The full payback period of biochar technology when calculating income for feed is 3.1 years, for milk and dairy products – 1.3 years.

The problem to provide the livestock industry of the North-West of Russia with forage grain has sharply escalated since 2010. Its successful solution is connected with the level and validity of the use of mineral and organic fertilizers. The purpose of the study, started by the Menkovsky Branch of the AFI in 2012, was to find effective options for the use of new organic-mineral fertilizer (OMF) which provides maximum agronomic effect and can produce grain of high quality. The methodological basis was the micro trials in polyethylene vessels without bottoms of 1 × 1 × 0.4 m in size with an artificially formed upper part of the profile of degraded sandy sod-podzolic soil. The soil was of 4.75 рНKCl, 3.46 mmol (eq) of Ng per100g, 3.20 mmol (eq) of Sch per100g, 1.83% of humus, 217 mg / kg of mobile compounds of phosphorus and 92 mg / kg of potassium. In the course of research, there was high agronomic efficiency of its use for winter wheat and satisfactory agronomic efficiency of its use for barley. When the winter wheat variety ‘Moskovskaya 56’ was fertilized with 5 t/ha of organic-mineral fertilizer containing 2.46% of Ng, 4.51% of P₂O₅ and 3.36% of K₂O, grain yield increased in 2.6 times. Fertilized with N75P50K50 the productivity improved in 3.8 times with a payback of 1 kg of NPK 7.4 and 5.6 grain units, respectively. It has been established that the combination of OMF with mineral fertilizers is accompanied by a significant yield increase with a decrease in its relative contribution from 153% to 59% and from 143% to 105% and a payback of 1 kg of NPK from 3.8 to 2.6 and from 6.9 to 4.7 of barley grain units and winter wheat grain units, respectively. The best indicators of the agronomic efficiency of OMF, both when applied in pure form and when fertilized with N75P50K50, corresponded to a dose of 4 t / ha. It has been found that the addition of 10 kg of potassium (К₂О) per 1 ton to OMF provided yield increase on 15% and the payback period of 1 kg NPK increased from 6.4 to 8.4 grain units. Qualitative indicators of wheat and barley grain fertilized with OMF improved due to the rise of raw protein percentage on 8–27% and a number of ash elements, such as CaO (from 0.07 to 0.11 mg/kg), MgO (from 0.16 to 0.21 mg/kg), Zn (from 21.5 to 23.6 mg/kg).

Представлены результаты исследований по комплексной оценке нового органоминерального удобрения на основе куриного помёта. Установлены его высокая агрономическая эффективность при трёхкратном за ротацию внесении в малых и средних дозах (окупаемость 1 кг NPK от 6,8 до 11,6 з.е.), а также способность останавливать развитие деградационного процесса в затронутой им почве. Существенные позитивные изменения агрофизических и физико-химических свойств почвы достигались применением высоких доз ОМУ (разовых – 7-10 т/га, среднегодовых – 3,3-5,7 т/га). На их фоне за 3 года обеспечивалось увеличение коэффициентов структурности и водопрочности структуры, соответственно, в 2,7 и 1,5 раза, показателей влагоёмкости – на 1,7%, рНKCl – на 0,47 ед., суммы обменных оснований – на 0,58 ммоль(экв)/100 г при уменьшении показателя средней плотности почвы на 0,04 г/см3. The results of studies on the complex assessment of a new organicmineral fertilizer based on chicken manure (OMU) are presented. Its high agronomic efficiency at three times for rotation of introduction in small and average doses (payback of 1 kg of NPK equaled from 6.8 to 11.6 grain units is establisheded.), as well as the ability to stop the development of the degradation process in the affected soil. Significant positive changes in agrophysical and physico-chemical properties of the soil were achieved by using high doses of WMD (single – 7-10 t/ha, average annual – 3.3-5.7 t/ha). In comparison with background, for 3 years, the increase in the structural and water – resistance coefficients of the structure was, respectively, by 2.7 and 1.5 times, the moisture content – by 1.7%, pHKCl – by 0.47, the amount of exchange bases-by 0.58 mmol(EQ)/100 g with a decrease in the average soil density by 0.04 g/cm3.

Spatial and temporal variability of growing conditions which affects the production process management is characteristic of agrophytocenosis.Spatial heterogeneity of soil essential properties is widely reported.A precision fertilization should be effective tool to control crop productivity.The highest potential of such fertilization could be expected for vegetable crops in the favorable soil and climatic conditions of the Nechernozemie of North-West Russia.In a microvegetation stationary two-factor experiment, plastic bottom-less pots of 1 m 2 area were used to artificially form the upper part of the soil profile (A arable 0-22 cm and А 2 В 22-40 cm horizons) simulating natural lithogenic mosaics of agro sod-podzolic sandy, sandy loam, light loam and medium loam soils subjected to weak and good cultivation.Their minimum, maximum, and average parameters for the 0-22 cm horizon were as follows: рН KCl of 4.34-6.35and 5.40, humus content (by Tyurin) of 0.92-2.50and 1.72 %, labile phosphorus and potassium (according to Kirsanov) of 125-550 and 390 mg/kg and 22-400 and 209 mg/kg, respectively.The vegetable crop rotation included black radish (Raphanus sativus L.)-potato (Solanum tuberosum L.)-beetroot (Beta vulgaris L.)-cabbage (Brassica oleracea L.)carrot (Daucus sativus L.).For a comparison, we used different system of fertilization, i.e. control (no fertilizers); zonal system (ZS); precision fertilization 1 (PF-1); precision fertilization 2 (PF-2).In the ZS providing for a uniform application of the fertilizers based on the average soil properties, we used lime (4.5 t/ha + N 95 Р 20 К 125 ) for black radish; manure (45 t/ha) + N 100 Р 30 К 90 for potatoes; N 130 Р 50 К 150 for beetroot; lime (2.1 t/ha) + manure (50 t/ha) + N 120 Р 10 К 90 for cabbage; and N 100 Р 40 К 130 for carrot.In the PF-1, two months before the radish was sown a precision soil cultivation has been performed using lime at 0-20 and 6.6 t/ha, peat at 0-900 and 390 t/ha; phosphorite flour at 0-750 and 94 kg/ha; potassium sulfate at 0-1710 and 407 kg/ha (as min-max and average).Further application of organic and mineral fertilizers before sowing (planting) was uniform, i.e.N 70 К 60 for black radish; manure (45 t/ha) + N 80 К 100 for potatoes; N 100 Р 30 К 130 for beetroot; manure (50 t/ha) + N 100 Р 10 К 70 for carrot; N 100 Р 10 К 120 for white cabbage.In PF-2 providing average doses of all fertilizers equal to these in ZS, but differentiated for each pot based on actual soil parameters, we used lime (0-12 t/ha) + N 70-120 Р 0-90 К 60-200 for black radish; manure (30-65 t/ha) + N 80-110 Р 0-110 К 70-150 for potato; N 90-170 Р 0-150 К 80-240 for beetroot; lime (2.1 t/ha) + manure (30-70 t/ha) + N 110-135 Р 0-60 К 40-120 for cabbage; N 85-115 Р 10-90 К 79-180 for carrot.The experiments were arranged in four replications.In a field experiment the precision fertilization provided an increase in the productivity of vegetable crop rotation of 22.3 and 43.5 t/ha in control and ZS, respectively, to 47.9-49.4t/ha.PF-1 and PF-2 resulted in the Сv reduction from 32 % and 16 % in the control and ZS to 9 %, and in an increased natural profitability of fertilizers by 21-49 %.A responsiveness of vegetable crop rotation to precision fertilization depended on biological features, the specific farming techniques and soil conditions.A decreasing responsiveness was as follows: black radish > car-rot  beet > potatoes > cabbage.A uniform application of high doses of organic fertilizers was the factor reducing precision fertilization effectiveness.Significant advantage of PF-1 compared to PF-2 was established only for black radish, beet and carrot.When designing precision fertilization technologies, one should take into account the following decrease in sensitivity of vegetable crops in crop rotation to optimized (reduced) doses of fertilizers in the well-cultivated parts of a field: cabbage > beet > carrot > radish black > potatoes.Due to differentiated doses of ameliorants and fertilizers and integrated optimization of soil properties, the precision fertilization eliminates the effect of soil heterogeneity in cultivation and granulometric composition on crop production and allows to increase productivity and payback of natural fertilizers to [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][17][18][19][20][21][22][23][24][25][26][30][31][11][12][13][14][15][16] when compared to ZS.

Установлены особенности изменения азотного режима песчаных подзолистой и дерново-подзолистых почв в процессе их окультуривания. Доказана возможность существенного его улучшения с помощью применения агротехнических мероприятий: посевов узколистного люпина и нетрадиционных видов органических удобрений (сапропеля и осадков сточных вод).

In order to assess the agronomical efficiency of new organo-mineral fertilizer (OMF), developed in collaboration with Bilavis LLC from poultry droppings, and its role in improving the farming sustainability, a microfield experiment was established in the Menkovsky branch of the Agrophysical Institute in 2012–2018. For the experiment, it was used polyethene containers without a bottom with a 1 m2 square. For the filling of the containers, the degraded average cultivated sod-podzolic soil was used. The fertilizer was used in a field crop rotation “green manure fallow (lupine), winter wheat, barley + perennial grasses, first-year perennial grasses, second-year perennial grasses, potato, spring rape”. The fertilizer was applied three times for winter wheat (3, 5 and 7 t/ha), barley and potato (4, 7 and 10 t/ha) separately and in combination with potassium fertilizer (10 kg K2O per 1 ton of the OMF) and complete mineral fertilizer (N75P50K50 and N100P75K75). The study found that the OMF from poultry droppings, produced by Bilavis LLC, had favourable technological properties. Given the specificity of the chemical composition (N:P:K = 1:1.8:1.4) and the alkaline reaction of the fertilizer, it should be preferably used on phosphorus-depleted soils of high acidity. The application of the OMF in field crop rotations on sod-podzolic soils in single doses from 3 to 10 t/ha (an annual average dose is from 1.6 to 3.9 t/ha) is justified both for potato and for grain crops. The average level of yield increase of potato tubers reached 77%, barley grain – 77% and winter wheat – 101%. The aftereffect was expressed in increasing the yield of green mass of blue lupine, perennial grasses and spring rape by 14–36%. The introduction of the OMF into the fertilizer system of the field crop rotation contributed to the stabilization of its productivity due to the integrated optimization of the soil conditions for the realization of the adaptive potential of crops to adverse weather and climate events. The variability of productivity of individual crops over the years decreased 1.4–1.8 times, and the variability of crop rotation in general reduced 1.7–2 times.

To assess the efficiency of spatial differentiation of the organic and mineral fertilizer rates in the grain-fallow rotation link the landscape field trial was established in 2013 at the Menkovo experimental station of the Agrophysical Research Institute. The object of study was a historically formed plot of arable land on a mild glacial origin slope of northwestern and western expositions with total area - 53.64 ha (including 47.3 ha of plowed field and 6.34 ha of hayland). The structure of the soil cover consists of a combination of small-contour complexes of light and medium-loamy varieties of soddy gleyed podzolic and gleyic soils. Parent rock is mainly represented by thin and medium loamy and clay sandy moraine underlying by glacial sandy loam on a depth of 75 – 120cm. Soils of medium fertility with plots of high and low fertility are dominated on plowed field. Five key plots of agromicrolandscape (AML) with different geochemical regimes have been selected. The impact of zonal and precision organo-mineral fertilizer system was studied in the "complete fallow – winter wheat – oats plus perennial grasses" crop rotation. Significant differentiation of the soil cover properties of arable land on a mild slope depending on the landscape and environmental conditions was established. The transition to precision agrochemical survey is relevant. The crop rotation link productivity within the five facies of the agricultural landscape varied from 4.98 to 8.68 t/ha in the variant without fertilizer application and from 7.59 to 14.6 t/ha in the variant with fertilizer application. The sufficiency of 1 kg NPK in the fertilizer application variant varied from 1.7 to 5.6 grain units. Sufficient grounds have not been revealed to explain this variability of the indicators only with the relief location and geochemical regime. The optimization of fertilizer rates with regard to specific geochemical regimes (an increase of 12% in AML and a decrease of 14% in AML due to the redistribution of organic and mineral fertilizers) provided increase the sufficiency of 1 kg NPK by 35 %. The methodological basis of such optimization induces a need to develop more detailed scientific argumentation.