par Drouet, Thomas 
;Herbauts, Jacques ;Demaiffe, Daniel
Référence Plant and soil, 394, 1-2, page (373-389)
Publication Publié, 2015-06
;Herbauts, Jacques ;Demaiffe, Daniel Référence Plant and soil, 394, 1-2, page (373-389)
Publication Publié, 2015-06
Article révisé par les pairs
| Résumé : | Background and aims: Acid leached soils developed on loessic materials in Central Belgium present homogenous edaphic characteristics and similar patterns of strontium isotopic composition (87Sr/86Sr), used as tracer of the origin of calcium. This was inconsistent with the large range of 87Sr/86Sr ratios measured in leaves from beech stands developed on the sites. We hypothesised that the deep carbonate-bearing horizon (>2.5 m) with low 87Sr/86Sr ratio, could be a complementary source of Ca for tree nutrition. Methods: We studied the change in foliar Sr isotopic composition and element concentrations in 12 forest sites along a soil sequence. This soil sequence was selected to include the largest range of variations in the depth at which the calcareous loess horizon occurs. In complement, root depth development was determined in six sites down to 300 cm. Results: Our results reveal that Sr originating from deep carbonate influences significantly the isotopic composition of beech trees growing on loessic soils. This influence contributes from 20 to 80 % to the Ca nutrition of trees depending on their position along the soil sequence. Conclusions: Despite its deep location in the soil profile, the carbonate-bearing horizon is determinant for the nutrient status of these forests. |
