ДИНАМИКА СОДЕРЖАНИЯ МИКРОЭЛЕМЕНТОВ В ПОЧВЕ ПРИ ОСВОЕНИИ МАЛОПРОДУКТИВНЫХ ЗАЛЕЖНЫХ ЗЕМЕЛЬ ВЕРХНЕВОЛЖЬЯ

Abstract

The studies were carried out at LLC Ruch’evskoe-1, Rzhevsky district, Tver region in 2012…2018 during development of low-yielding, previously reclaimed lands that were retired from circulation. The total area of arable land is 5297 hectares, the soils are sod-podzolic, light loamy in terms of particle size distribution. The effect of the systematic application of high doses of organic fertilizers from pig-breeding complexes in the form of solid fraction of manure (60…80 t/ha) and liquid waste (100…120 m3/ha) on the dynamics of the content of copper, zinc, boron and manganese in the arable layer has been studied. It was found that during the six-year observation period on soils with a leaching type of water regime, the average weighted copper content had only positive tendency to increase as the increment to the initial value was 0.1 mg per a kilogram of soil (0.1 mg/kg), which was within the experimental error and amounted to 1.7 mg/kg at the optimal value for the region 2.45 mg/kg. A similar situation is typical in the study of the dynamics of zinc, the average weighted content of which reached 0.9 mg/kg, which is significantly lower than the optimal level of 3.55 mg/kg. Consequently, with the deacidification of fallow lands from the introduction of alkaline organic fertilizers, a significant increase in the available forms of copper and zinc was not noted, which requires additional introduction of microelements to eliminate their deficiency. At the same time, the systematic application of high doses of organic fertilizers significantly improved the provision of low-yielding lands with boron and manganese, the content of which in the arable layer approached the optimal value and at the end of observations amounted to 0.50 and 44.8 mg/kg, respectively, with an optimal level of 0.52 and 50.5 mg/kg.