Resistance of solonetzic soils to rocket and space activity impact in central Kazakhstan.

Abstract

Introduction. This paper provides the results of a comparative analysis of physicochemical and biological characteristics of soil cover at the fall places of the first stage of “Proton" Launch vehicle (LV) in the area of Yu-2 (Central Kazakhstan). In particular, we considered the ecological stability of brown solonetzic soils in combination with Solonetz soil, to chemical pollution and variability of soil microflora to mechanical stresses during the fall of the separated parts of space launch vehicles (SLV SP). Materials and Methods. We have chosen those Kazakhstan's territories that are used by the Baikonur Cosmodrome as an impact areas of separating parts of space launch vehicles (SLV SP IA), in June 2017, to conduct ecological studies in those places, where the first-stage vehicles of the Proton rocket have been fallen in the Yu-2 zone (Central Kazakhstan). Here the pollution of UDMH (unsymmetric dimethylhydrazine, rocket fuel, substance of the 1st class of toxic hazard) has been detected in soils in 2000-2007. Control point were also chosen in the adjacent territory. Morphological and physico-chemical properties of soil profiles have been studied. In 10 soil samples, indicators of the state of microflora and phytotoxicity were determined. Results and Conclusions. Based on the results of the analysis of the characteristics of solonetzic soils at the fall places of separated parts of space launch vehicles "Proton" in the Yu-2 zone (Central Kazakhstan), it was concluded that they have high resistance to chemical pollution of UDMH. The processes of physico-chemical transformation of UDMH and its processing by soil microorganisms are assumed in the illuvial B horizons, due to the high content of exchangeable sodium, against the background of sufficient soil moisture with an alkaline pH-medium (up to strongly alkaline). At the same time, low microbiological indices, the absence of spore-forming bacteria, and the presence of plant phytotoxicity were found in soils of the fall places. Microbiological restoration of fertile top soil in technogenic disturbed lands of the Yu-2 zone is extremely difficult in conditions of high soil alkalinity, in the presence of saline clay and increased content of carbonates