Mineral elements in the root biomass of a low-shrub pine bog community
1990
Braekke, F.H. | Haaland, B. (Norsk Inst. for Skogforskning, Aas (Norway))
Elements which were included in the study, were as follows: N, K, Ca, Mg, P, S, B, Zn, Cu, Pb. The element concentrations of the large Scots pine roots (diameter greater than 10 mm) increased systematically with distance from the stump both in the bark and the wood. The concentrations of Ca, Mg, Zn and B in pine fine (diameter less than 1mm) and small (diameter equal to 1-10 mm) roots (bark plus wood) lay between the values for wood and bark in the outer part of pine large roots. Sulphur and P levels were about the same as in the bark, while N, Pb and Cu were above. Levels of S and Zn were markedly higher in the field vegetation roots than in the pine roots. The concentrations of K, Ca and B decreased with depth both in the field vegetation, and the pine roots, while S and Zn increased with depth in the field vegetation roots. Compared with the ratios for biomass, relative contents of all elements, except S and Pb, were lower in the roots than in the above-ground parts. The nutrient balance in the roots indicates a low supply of K, P, B and 'luxury' uptake of S, Zn, Cu. The circulation of Pb seemed to be restricted, with some accumulation in the roots.
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