HIDDEN RESERVES OF INCREASE OF EFFICIENCY OF AGRICULTURE IN THE NORTH-WEST OF RUSSIA
Authors: Иванова Ж.А. , Костыгова В.В. , Пономарёва М.А. 
Published: August 2024

В многоуровневых полевых, вегетационных и лабораторных экспериментах на дерново-подзолистых почвах установлены параметры агрономической эффективности и детоксикационные свойства органо-глинистого и известковистого сапропелей. Выявлено их положительное влияние на питательную ценность фуражного зерна и зеленой массы многолетних трав.
Local fertilizers remain an available resource for curbing degradation processes in agricultural soils of the North-West of Russia. For this purpose, the deposits of sapropelic raw materials, whose reserves in the region are 7 billion m3 , are promising. Modern methods of remote sensing can significantly reduce the cost of integrated development of individual sapropel deposits. The study was carried out in a series of laboratory, vegetation and microfield experiments. Studied in detail the properties of sapropel deposits of Small lakes and Boron Lazowska Velikoluksky district of the Pskov region. Sandy and medium-loamy sod-weakly podzolic soils with agrochemical characteristics: phkcl 6,46–6,75 and 4,12–4,90; humus content 0,70–1,03 and 2,00– 2,10%, mobile phosphorus compounds 220–263 and 198–236 mg/kg and potassium 70– 148 and 120 – 225 mg/kg, respectively. Sapropel fertilizers were used in the dried and 165 natural state at random and in the alluvium at doses of dry matter from 30 to 100 t/ha. In addition, options for their joint application with manure and mineral fertilizers were studied. In vegetation and micropolish experiments stretch the cultivated barley varieties of Elf and fescue varieties Pskov local. Repetition of the experiments 3 to 4- fold. Organo-clay sapropel has very little effect on the acid-base properties, phosphate and potassium state of sandy loam and medium-loamy sod-podzolic soils. At the same time, at a dose of 30 t/ha, it optimizes their nitrogen regime. In the field, the spread application of 44 t/ha of dried sapropel in the first year increases the content of ammonium exchange by 106–115 %, nitrates by 36–62 %. Alluvial deposition, especially in medium loam soil, affected by weaker – increase the first figure reaches 48 %, other 32 %. On agronomic efficiency on crops of an oatmeal the meadow dried organic-clay sapropel and manure in average doses are equal. Sapropel increases the yield of dry matter of meadow fescue on 14–23% in the year of application and on 17– 23% in after-effect, providing for three years the energy efficiency ratio at the level of 4.59 – of 5.83 units. The absolute increase in yield from the use of sapropel on mediumloamy soil is higher than on sandy loam by 40%. Precoat application of sapropel 5% less efficiently broadcast only in strongly acidic medium loamy soil. The addition of dried organo-clay sapropel with mineral fertilizers and manure is ineffective. Organoclay sapropel is advisable to use for grain and perennial herbs at doses of 40–50 t/ha on sod-podzolic soils of sandy loam and loamy granulometric composition. Given that the effectiveness of this fertilizer is largely dependent on the nitrogen content, the amount of the latter at the introduced dose should not be less than 200 kg. The use of naturally moist sapropel is more effective on soils of light granulometric composition in doses of 100–120 t/ha. in terms of man-made soil contamination with cadmium, as well as on strongly and medium-acid soils, it is justified to use local resources of lime sapropels as a meliorant, using them in doses up to 30 t/ha.