Plant Uptake of Trace Metal Oxoions From Two Contrasting Acid Soils

Abstract

Uptake of arsenic, molybdenum, uranium and vanadium by species of natural vegetation (Agrostis capillaris, Betula pendula, Calluna vulgaris, and Deschampsia flexuosa) on two contrasting, highly acid soils (pH of soil solution 4.2–4.3), differing in natural abundance of these elements, was compared. the soil developed from alum shale was rich in these elements, the soil from a gneiss moraine was poor in these elements. Leaf/ above ground biomass concentrations were positively related to soil concentrations of the elements, but least closely for uranium, and vanadium tended to be excluded by the plants, compared to arsenic, and especially to molybdenum. the relationships between soil and plant concentrations were broadly similar whether nitric acid-digestible or the much lower DTPA extractable soil fractions were considered. Leaf concentrations of plants from the shale and the gneiss soil, respectively, ranged 1.41–2.76 and 0.30–0.58 nmolg⁻¹ dry weight for arsenic, 14–140 and 0.5–9.6 for molybdenum, 0.031–0.069 and 0.013–0.030 for uranium, 2.3–6.4 and 0.75–3.3 for vanadium.

Key Words:

• Arsenic
• molybdenum
• plant
• uptake
• uranium
• vanadium