¹B. Basso, ²J. Destain, ³B. Bodson, ⁴M. Destain, ⁴B. Dumont

1. Michigan State University, Dept. Geological Sciences and W.K. Kellogg Biological Station, Lansing, MI, USA
2. Gembloux Agro-Bio Tech - ULg, Walloon Agricultural Research Centre (CRA-W), Gembloux, Belgium
3. Gembloux Agro-Bio Tech - ULg, Dept. Agronomical Sciences, Gembloux, Belgium
4. Gembloux Agro-Bio Tech - ULg, Dept. Environmental Sciences and Technologies, Gembloux, Belgium