Skip to Main content Skip to Navigation
Journal articles

Magnesium Isotope Variations to Trace Liming Input to Terrestrial Ecosystems: A Case Study in the Vosges Mountains

Abstract : Liming with Ca and Mg carbonates is commonly used to reduce soil and stream acidity and to improve vegetation growth and nutrition in forests. Ten years ago, dolomite lime was experimentally applied to a forest catchment on granite in the Vosges Mountains (northeast France), which is characterized by acid soils and drained by an acid stream. The average Mg isotope composition of the dolomite lime (-1.75%) was low compared with that of tree foliage (-0.70%), granite and deep soil layers (-0.40%), and stream water (-0.80%) in the control catchment. After liming, the exchangeable Mg concentrations in surface soil layers, which were initially very low, increased, and the Mg isotope composition decreased (up to -0.60%). The decrease was smaller in deeper layers but not in proportion to the increase in exchangeable Mg content, suggesting contributions from mineralization of organic matter and/or displacement of exchangeable Mg from surface layers. Before application, Mg concentration in beech and fir leaves was low, and that of 1-yr-old fir needles was lower than that in current needles. Internal Mg translocation within fir needles also resulted in a lower delta Mg-26 of older needles. Three years after dolomite application, the Mg isotope composition of plant leaves was lower than that in the control catchment; this decrease (up to -1.00%) was attributed to direct uptake of Mg from dissolving dolomite. Liming doubled the concentration of Mg in the stream, whereas the Mg isotope composition decreased correspondingly from -0.80 to -1.20%, indicating a fast transfer of dolomite Mg to the stream. Our findings indicate that monitoring of delta Mg-26 may be a promising tool to study the fate of dolomitic inputs in terrestrial and aquatic ecosystems.
Document type :
Journal articles
Complete list of metadatas

https://hal.univ-lorraine.fr/hal-01557917
Contributor : Silva Ul <>
Submitted on : Thursday, July 6, 2017 - 4:13:06 PM
Last modification on : Friday, November 6, 2020 - 3:29:32 AM

Identifiers

Citation

B. Emile Bolou-Bi, Etienne Dambrine, Nicolas Angeli, Benoît Pollier, Claude Nys, et al.. Magnesium Isotope Variations to Trace Liming Input to Terrestrial Ecosystems: A Case Study in the Vosges Mountains. Journal of Environmental Quality, Crop Science Society of America, 2016, 45 (1), pp.276-284. ⟨10.2134/jeq2015.02.0096⟩. ⟨hal-01557917⟩

Share

Metrics

Record views

310