Influence of red mud on soil microbial communities: Application and comprehensive evaluation of the Biolog EcoPlate approach as a tool in soil microbiological studies

• Published in: The Science of the total environment Vol. 595; pp. 903 - 911
• Main Authors: Feigl, Viktória, Ujaczki, Éva, Vaszita, Emese, Molnár, Mónika
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.10.2017
• Subjects: Biodiversity; Biolog EcoPlate; Community-level physiological profiling; Environmental Monitoring; Hungary; Red mud; Soil - chemistry; Soil amendment; Soil microbial community; Soil Microbiology; Soil Pollutants; Trace Elements; Red mud; E; Biolog EcoPlate; Soil amendment; H; AWCD; LQS; Community-level physiological profiling; Soil microbial community; RMSM; S; OD; CLPP; SAWCD; RM; SR
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2017.03.266

Red mud can be applied as soil ameliorant to acidic, sandy and micronutrient deficient soils. There are still knowledge gaps regarding the effects of red mud on the soil microbial community. The Biolog EcoPlate technique is a promising tool for community level physiological profiling. This study presents a detailed evaluation of Biolog EcoPlate data from two case studies. In experiment “A” red mud from Ajka (Hungary) was mixed into acidic sandy soil in soil microcosms at 5–50 w/w%. In experiement “B” red mud soil mixture was mixed into low quality subsoil in a field experiment at 5–50 w/w%. According to average well color development, substrate average well color development and substrate richness 5–20% red mud increased the microbial activity of the acidic sandy soil over the short term, but the effect did not last for 10months. Shannon diversity index showed that red mud at up to 20% did not change microbial diversity over the short term, but the diversity decreased by the 10th month. 30–50% red mud had deteriorating effect on the soil microflora. 5–20% red mud soil mixture in the low quality subsoil had a long lasting enhancing effect on the microbial community based on all Biolog EcoPlate parameters. However, 50% red mud soil mixture caused a decrease in diversity and substrate richness. With the Biolog EcoPlate we were able to monitor the changes of the microbial community in red mud affected soils and to assess the amount of red mud and red mud soil mixture applicable for soil treatment in these cases. [Display omitted] •Selected Biolog EcoPlate indices are applicable to assess the effect of red mud.•Red mud at 5–20% enhances the microbial activity of an acidic sandy soil.•Microbial diversity is decreasing upon red mud addition over the long term.•10–20% red mud-soil mixture enhances microbial acitivity of degraded soil.