INFLUENCE OF HUMIC PREPARATIONS ON DEGRADED SOILS PROPERTIES OF TECHNOGENIC BARRENS

Abstract

This research aim was testing the applicability of exogenic organic matter – extracted humic substances – for the remediation of technogenic barrens soils near Cu-Ni smelter (Kola Peninsula). In short-term laboratory experiments we studied the possibility of stabilization of heavy metals labile forms by commercial humic substances (HS) of different origin (peat humate “Flexom” and coal humate “Extra”) in comparison with HS, inoculated by microorganisms – nitrogen fixers and mycorrhizae-forming fungi and mineral fertilizers (NPK и CaCO3). Experiments were provided during 45 days after 14 days of pre-incubation under controlled conditions in climate chamber with light, temperature and humidity imitating the polar day conditions in Kola Subarctic. After experiments we evaluated changes in soil chemical properties, soil microbial community and test-culture (Deschampsia cespitosa). Peat humate application is ineffective without additional manipulations (e.g. combination with CaCO3), cooperation with biological applicants cannot be pointed out. Application of coal humate favours to metals stabilization, soil microorganism’s activation, test-culture growth. It may be effective to combine coal humate with biological applicants like mycorrhizae-forming fungi. So, coal-humates may be perspective growth-stimulator, ameliorant and detoxicant in remediation of degraded soils in conditions of polymetallic contamination.