Response of Soil Enzyme Activity and Microbial Community in Vanadium-Loaded Soil

Yang, Jinyan; Huang, Jen-How; Lazzaro, Anna; Tang, Ya; Zeyer, Josef

Response of Soil Enzyme Activity and Microbial Community in Vanadium-Loaded Soil

2014

Yang, Jinyan | Huang, Jen-How | Lazzaro, Anna | Tang, Ya | Zeyer, Josef

Vanadium (V) is an essential trace element for certain biological enzymatic reactions but becomes toxic at higher concentrations. The impact of V at concentrations of 0 − 500 mg/kg V(V) spiked in soils on soil enzymatic activities, and microbial diversity was investigated in soybean pot experiments. The results from sequential extraction of soil V indicated increasing V mobilizable fractions with increase of soil V concentrations. The soil sulfatase activity decreased drastically from 2.35 − 5.55 to 0.30 − 0.88 μmol methylumbelliferon (MUB)/[h g soil] with increasing soil V loading at different vegetative stages. Surprisingly, the activity of soil phenol oxidase increased from 0 − 0.73 to 3.74 − 7.61 μmol L-3,4-dihydroxyphenylalanine (DOPA)/[h g soil] with increasing soil V concentrations at different vegetative stages probably due to oxidation stress caused by V in soils. These observations were not affected by the presence of soybean plants. In comparison, soil phosphatase, protease, and ß-glucosidase showed no significant reaction to V concentrations in soil. Both fungal and bacterial communities changed significantly at different levels of V treatments. Accordingly, V may pose a threat to some biologically mediated functions in soils even at low bioavailable amounts.

Показать больше [+]