title: Comparison of element concentrations in fir and rhododendron leaves and twigs along an altitudinal gradient.
abstract: Concentrations of 23 elements (Ca, K, Mg, P, Al, Cu, Fe, Mn, Mo, Na, Ni, Zn, Ag, Ba, Be, Cd, Co, Cr, Pb, Sb, Th, Tl, and V) in leaf and twig samples of a fir (Abies fabri) and a rhododendron (Rhododendron williamsianum) collected along an altitudinal gradient on Mount Gongga, China, are reported in the present study. Most of the macronutrients (K and P), micronutrients (Fe, Zn, Cu, Na, Ni, Mo, and Al), and trace elements (Pb, Tl, Ag, Cd, Ba, Co, V, Be, and Cr) are significantly enriched in fir when compared to rhododendron; however, Ca, Mg, Mn, Ba, and Cd are more enriched in rhododendron than in fir. Most of the elements in both plants are more significantly enriched in twigs than in leaves. The relationship between element concentration in plants and altitudinal gradient is nonlinear. Altitudes of 3,200 and 3,400 m are turning points for fir and rhododendron growth, respectively. Concentrations of all trace elements in the two plants along the altitudinal gradient are well below the toxic level in plants. No known industrial sources of the elements investigated exist in the Mount Gongga area, China. Element concentrations in the present study are higher than those found in mosses collected from the same area, indicating that the area is not contaminated. The element concentrations that we observed in plant samples were due to soil uptake. The pronounced differences between the two species are due to the different uptake characteristics of fir and rhododendron.
authors: Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, China. shouqinsun@imde.ac.cn
authors: Shou-Qin
authors: SQ
authors: Sun
authors: Yan-Hong
authors: YH
authors: Wu
authors: Jun
authors: J
authors: Zhou
authors: Dong
authors: D
authors: Yu
authors: Ji
authors: J
authors: Luo
authors: Hai-Jian
authors: HJ
authors: Bing
mesh_terms: D028202:Abies / Q000737:chemistry*; D000531:Altitude; D002681:China; D004784:Environmental Monitoring; D018515:Plant Leaves / Q000737:chemistry*; D018547:Plant Stems / Q000737:chemistry*; D029793:Rhododendron / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis; D013045:Species Specificity; D014131:Trace Elements / Q000032:analysis*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014131:Trace Elements