Technogenesis and Main Morphotypes for Technogenically Disturbed Soils of Landscapes of SMW Landfills.
Olga S. Bezuglova and Dina G. Nevidomskaya. Rostov State University, Bolshaya Sadovaya, 105, Rostov-on-Don, Russia
As the result of functioning of SMW (solid municipal wastes) landfills the soil cover of adjucent landscapes undergoes considerable transformations and this is manifested in reducing initial soil-forming processes typical for chernozems of the given subtype and in dominating processes arising under the influence of technopedogenesis. We studied impacts of SMW landfills on the soil cover of calcareous ordinary chernozems for the steppe zone of the South of Russia (Rostovskaya oblast'). The studies were carried out on functional and recultivated SMW landfills. The following priority impacts were revealed after studying the whole range of characteristics of explored soils of landscapes of SMW landfills: technointermixing accompanied with horizontal and profile destructions of soil mass; technogenically-provoked underflooding; soil alkalinization; pollution with anthropogenic inclusions as the result of littering and deluvial adding from accumulative anthropogenic landscape in the form of dump "body"; influence of biogas from the dump "body" on the material of recultivated ground. Revealing of typical soil-forming processes intrinsic to calcareous ordinary chernozems becomes recessive but under technopedogenesis the processes forming soil genesis for areas of SMW landfills start dominating: the process of artificial overcompaction of soil and ground material, technogenic alkalinization, processes of migration of manganese and iron compounds, metamorphisation of organic matter, magnesia alkalinity, revealing of redoximorphic process progressing in the dump "body". It is established that in the upper horizons of technogenically-changed soils of the recultivated landfill primary ruderal vegetation stimulates to renewal of sod-forming process that is shown in predominating of humus plasma at the microlevel. At the macrolevel it causes changing of colour and improving of structure and water and air properties. In the situation of technopedogenesis contrast intrasoil conditions are created and they change the character of initial new formations and inclusions and are conductive to synthesis of autogenic mineral formations: different forms of calcite, iron contractions, iron and manganese concretions. Minerals with unregulated structures – formations with mixed layers - prevail in the composition of mineral components of technogenically disturbed soils and the content of illitic minerals, kaolinite, and quartz increases, as well. Studies of the soil cover on areas of SMW landfills permits to mark out the following morphotypes for soil profiles the forming of which is connected with the dominating kind of influence: I. Technozem chernozem-like intermixed; II. Technozem chernozem-like hydrometamorphised; IIIr Technozem chernozem-like sod-washed intermixed; IV. Humus gleyic pelozem underlain with municipal wastes. Key words: landfills of solid municipal wastes, calcareous ordinary chernozem, technopedogenesis, technogenically changed soil.