Parameters of microbial respiration in soils of the impact zone of a mineral fertilizer factory

Abstract

The carbon content in the microbial biomass and the microbial production of CO 2 (the biological component of soil respiration) were determined in the upper layer (0-10 cm) of soils in the impact zone of the OJSC Voskresensk Mineral Fertilizers, one of the largest factories manufacturing mineral fertilizers in Russia. Statistical characteristics and schematic distribution of the biological parameters in the soil cover of the impact zone were analyzed. The degree of disturbance of microbial communities in the studied objects varied from weak to medium. The maximum value (0.44) was observed on the sampling plot 4 km away from the factory and 0.5 km away from the place of waste (phosphogypsum) storage. Significantly lower carbon content in the microbial biomass and its specific respiration were recorded in the agrosoddy podzolic soil as compared with the alluvial soil sampled at the same distance from the plant. The effects of potential soil pol lutants (fluorine, sulfur, cadmium, and stable strontium) on the characteristics of soil microbial communities were described with reliable regression equations.

Review of the State of Impurity Occurrences and Impurity Removal Technology in Phosphogypsum

“…China is the world’s largest phosphate fertilizer producer and has become the world’s largest phosphogypsum resource by-product country, with annual production in phosphogypsum of about 75 million tons, but the comprehensive utilization rate is about 45% only; as the accumulated stockpile has reached 830 million tons, which takes up a lot of land, there is a serious risk of environmental pollution [ 1 , 2 , 3 , 4 ] and a waste of precious resources of calcium and sulfur. The main component of phosphogypsum is calcium sulfate dihydrate.…”