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81.
Trace element concentration in wheat grain: results from the Swedish long-term soil fertility experiments and national monitoring program 总被引:4,自引:1,他引:3
Holger Kirchmann Lennart Mattsson Jan Eriksson 《Environmental geochemistry and health》2009,31(5):561-571
Concentrations of trace elements in wheat grain sampled between 1967 and 2003 from the Swedish long-term soil fertility experiments
were analyzed using ICP-MS. The long-term effect of inorganic and organic fertilization on trace metal concentrations was
investigated including the impact of atmospheric deposition and myccorhiza, whereas other factors such as soil conditions,
crop cultivar, etc. are not discussed in this paper. Mean values derived from 10 experimental sites were reported. Significantly
declining Pb and Cd concentrations in wheat grain could be explained by lower atmospheric deposition. Mean Se contents in
all samples were 0.031 mg kg−1 grain dry weight. No samples had sufficiently high Se concentrations for human (0.05 mg Se kg−1) or animal demand (0.1 mg Se kg−1). Concentrations of Co in wheat grain were extremely low, 0.002–0.005 mg Co kg−1 grain dry weight, and far below the minimum levels required by animals, which applied to all fertilizer treatments. A doubling
of Mo concentrations in grain since 1975 resulted in Cu/Mo ratios often below one, which may cause molybdenosis in ruminants.
The increase in Mo concentrations in crops correlated with the decline in sulfur deposition. Concentrations of Cu and Fe declined
in NPK-fertilized wheat as compared to unfertilized or manure-treated wheat. Very low concentrations of Se and Co and low
concentrations of Fe and Cu require attention to counteract risks for deficiencies. The main characteristic of the study is
that there are few significant changes over time between different fertilizer treatments, but throughout there are low concentrations
of most trace elements in all treatments. In general, good agreement between concentrations in wheat from the long-term fertility
experiments and the national monitoring program indicate that values are representative. 相似文献
82.
Lennart Klynning 《Die Naturwissenschaften》1962,49(11):252-252
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