Nutrient regime of agrochernozems in oilseeds cultivation in the Kansk forest-steppe

Abstract

The study was conducted on chernozem-type soils prevailing in the Kansk forest-steppe. The aim of the investigation is to study the temperature and nutrient regime of agrochernozems in spring rapeseed and camelina sativa cultivation. By the period of oilseeds sowing, the temperature did not reach a stable transition through + 5°C of the soil layer at the depths of 0-20 cm. From May to June, the soil temperature sharply increases up to +13-16°C, and in July it warmed up to 29-30°C. In August, agrochernozems cooled up to + +5-12°C. It has been found that a 0–20 cm layer of the camelina sativa agrocenosis is on average in 2°C warmer than rapeseed. The quantitative parameters resulting from the processes of ammonification and nitrification in the oilseeds agrocenoses are inversely related. The differences in the quantitative estimation of mineral nitrogen in the rapeseed and camelina sativa agrocenosis are not statistically proven. The initial identical high availability level of labile phosphorus in the oil crops agrocenoses is associated with the predecessor. The decline of this indicator in the rapeseed and camelina agrocenosis to a low level of security in the July period is due to its expenditure on the formation of plant productivity. The availability of exchangeable potassium for agrochernozems in agrocenoses is average, but in absolute terms it is higher in soils of camelina sativa agrocenosis.