Soil Formation on Sugar Industry Waste in the Central Chernozem Zone

Abstract

Soils formed in treatment facilities of sugar beet factories in the forest-steppe zone of the Kursk region were studied. The technogenic factors of soil formation associated with the industrial sugar beet activity, and post-technogenic processes, acting during the abandonment of treatment facilities, are considered. The alternation of settling ponds and the earth walls separating them is the main factor determining the kind of “cellular” pattern of the soil cover. The mode of inflow and discharge of wastewaters, their composition, as well as the duration of the abandonment of settling ponds determine the specifics of the soils formed in the bottoms of the ponds. In operating settling ponds, under the periodic impact of sewage mixed with other wastes, dark-humus quasigleyic soils are developed (Calcaric Gleysol). When ponds are abandoned with previously removed calcareous sewage sludge (press mud), in the presence of perched water dark-humus quasigleyic soils (Gleyic Cambisol) are formed in 30 years; and in conditions of a variable-humid regime, quasigleyic zooturbated Chernozems are formed in 40 years. In settling ponds with preserved sewage sludge abandoned 20 years ago, soil formation has been noticeably active only in the upper 10–15 cm; below, the properties of the layered sediment are retained. Dark-humus technogenic arti-stratified soils are identified here (Spolic Technosols). On the earth walls, dark-humus typical soils (Eutric Cambisols (Organotransportic) are formed in 70 years; on the surfaces covered with calcareous sewage sludge, underdeveloped highly alkaline technogenic pelozems (Spolic Technosols (Transportic) are identified, in which the mixed material of technogenic sediments remains practically unchanged. All soils are alkaline and strongly alkaline, rich in organic matter, carbonates, phosphates, nutrients and some heavy metals from wastewater. According to the combination of properties and characteristics, the soils of the sugar industry treatment facilities have no direct natural analogues in the Central Chernozem region and are a vivid example of soils developing under ext-reme conditions of “resource excess”.