PH10 Soil Ecotoxicology and Risk Assessment
Exhibit Hall
8:00 AM - Thursday
(PH128) Effects of phytoremediation strategies on the metabolic diversity of indigenous microbial communities in metal-contaminated soils.
Humphries, J.1, Bens, C.2, Cox, S.1, Neuman, D.3, Zak, J.1, Hooper, M.1, 1 Texas Tech University, Lubbock, TX, USA2 National Wildlife Research Center - USDA, Fort Collins, CO, USA3 Montana State University, Bozeman, UT, USA
ABSTRACT- Soil microbial communities are critical for revegetation of metal contaminated soils, due to their impacts on soil health, nutrient cycling, and plant - root interactions. Metabolic diversity and soil microbial community structure previously have been found to be heavily impacted by phytoremediation and revegetation amendment strategies. This study was designed to characterize the effects of various phytoremediation amendment strategies on indigenous soil microbial communities in metal contaminated soils surrounding the Anaconda Smelter Superfund site in Deer Lodge County, Montana. A 1.5 acre study area was divided into six experimental plots, which were plowed and amended with combinations of liming materials, fertilizer and organic matter. They were then uniformly seeded with grasses, legumes and shrubs as described previously by the Reclamation Research Unit of Montana State University. Soil adjacent to the study area remained unamended and served as the experimental control. Substrate utilization patterns of bacterial and fungal communities were assessed using Biolog microtiter plates, and data were analyzed via canonical correspondence analysis (CCA) and non-metric multidimensional scaling (NMDS). Soil profiles (metal concentration, pH, % moisture content, % organic matter, soil nutrients) of amended and non-amended plots differed significantly. Total activity of bacterial communities differed among plots to a greater extent than did the number or identity of substrates utilized. Metabolic activity of fungal communities did not differ among plots. These findings suggest that microbial community activity and diversity were more sensitive to the presence/absence of remedial action than to the specific characteristics of the remedial activities. Sponsored in part by NIEHS grant P42ES04696.
Key words: microbial communities, phytoremediation, multivariate analysis