PRODUCTIVITY OF CROP ROTATION ELEMENT AND QUANTITY OF AGRICULTURAL PRODUCTION WHEN USING SEWAGE AND ORGANIC COMPONENTS MIXTURE

Abstract

The expediency of introducing wastewater sediment (WWS) in fresh form together with additional fillers (peat, sawdust, straw) is justified. Field experience was conducted in 2015-2017. using WWS station of treatment facilities in Tver on sod-podzolic sandy loam soil. WWS was applied once during the laying of the experiment together with organic substrates in different proportions with a general application rate of 60 t/ha. For comparative characteristics, the experiment included a variant with compost harvested at the treatment plant, based on WWS and sawdust. The influence of non-traditional types of organic fertilizers on the yield of field crops (vetch-oat mix, winter rye, spring barley), the quality of the resulting product, including the accumulation of heavy metals in it, was revealed. The greatest effect was observed when applying WWS with peat and WWS with sawdust. The study of the ratio of the components of mixtures with WWS showed that the highest productivity and yield increase was ensured by the use of WWS: substrates = 1: 1. A further increase in the participation of sawdust, peat and straw led to a decrease in productivity and quality indicators. WWS, introduced in different ratios together with organic substrates, did not cause excessive accumulation of heavy metals in crop production. The sequence of heavy metals was established: Zn> Cu> Co> Pb> As> Cd, which reflects the degree of their accumulation in the green mass of the vetch-oat mix, winter rye and barley grain. The influence of the studied norms for introducing WWS on the yield and quality of crops is maintained during all three years of the crop rotation link.