Native prairie grasses and microbial community responses to reclamation of taconite iron ore tailing

Abstract

The effect of reclamation treatments on seeded native grass cover and species composition, soil microbial biomass carbon, and populations of actinomycetes, fungi, free-living N2-fixing bacteria, and aerobic heterotrophic bacteria was compared in field plots in coarse taconite tailing. Reclamation treatments consisted of all possible combinations of three rates of composed yard waste, three rates of fertilizer, and inoculation with arbuscular mycorrhizal fungi. Composted yard waste increased plant cover, soil microbial biomass, and populations of all groups of microorganisms compared with unamended, non-inoculated control plots. Microbial populations and biomass in tailing plots were low compared with natural soils and were correlated with plant cover and available P. Mycorrhizal inoculation resulted in a 6% increase in plant cover, although this was not significant, and significantly enhanced N2-fixer populations in June but did not affect other groups of microorganisms. There were no differences between moderate and high rates of composted yard waste. We conclude that incorporation of a moderate rate of organic matter can ameliorate the stressful conditions of coarse taconite tailing and can enhance the initiation of a functional soil ecosystem able to support the establishment of seeded native prairie grasses and may provide a long-term solution to reclamation of taconite tailing. Key words: arbuscular mycorrhizal fungi, mine reclamation, soil microorganisms, composted yard waste.

Ecological Potential of Plants for Phytoremediation and Ecorestoration of Fly Ash Deposits and Mine Wastes

“…Microbial and fungal activity is important for restoration of mine tailings, establishment of plants and biogeochemical cycling (Noyd et al, 1995), particularly in acid mine drainage (Mills, 1985). Microorganisms change the bioavailability of heavy metals, solubilization of minerals in mine tailings, release nutrients, supply them to the plants, and enhance plant growth (Moynahan et al, 2002;Wu et al, 2006).…”

Arbuscular mycorrhizal fungal inoculation protects Miscanthus×giganteus against trace element toxicity in a highly metal-contaminated site

“…The establishment of vegetation on contaminated soils could be difficult due to metal toxicity, low nutrient content, degraded microbial communities and poor physical structure of the substrate (Noyd et al, 1995;Ussiri and Lal, 2009). Despite the high tolerance observed in Miscanthus, several studies have shown that TEs induce a reduction of its aerial biomass (Ezaki et al, 2008;Sharmin et al, 2012;Wanat et al, 2013).…”

Effects of a New Waste‐Processing By‐product on Soil and Vegetation at Fort Campbell, Tennessee

“…Because weedy plants usually respond better to fertilization than warm-season prairie grasses, this result may be due to increased mycorrhizal infectivity as weedy grasses did not diminish with increasing application rate but prairie grasses increased. A study conducted on iron mine tailings in Minnesota found that composted yard waste significantly increased vesicular-arbuscular mycorrhizal infectivity compared to inoculation using some of the same species planted in this study and that available P increased more in the plots amended with the compost than with fertilizers (Noyd et al 1995;Noyd, Pfleger, and Norland 1996). However, given that soil P levels only increased in the depths where pulp was incorporated, decomposition of the Fluff and subsequent mineralization of P was most likely responsible, regardless of the effect of pulp on mycorrhizal infection.…”