%0 Journal Article %T Effect of high doses of superphosphate on the group and fractional composition of phosphates containing in dark gray forest soil %A Karengina, L.B. %A Baykin, Y.L. %A Baykenova, Y.G. %K dark-gray forest, doses of superphosphate, availability index, forage beans, group content, fractional content %J Agrarian Bulletin of the %D 2021 %N 0 %P 8 %I Ural State Agrarian University