Foliar excretion of two understorey ligneous species in an alluvial forest

This paper concerns actual foliar excretion of nutrients in a flooded alluv ial forest enriched in nutrients by floods and the possibility of its modif ication after suppression of floods. Two species of the understorey Cornus sanguinea and Prunus padus were tested in a flooded site and an unflooded o ne. The main nutrients excreted were calcium and sodium. Nitrate is never e xcreted; phosphate, magnesium and potassium are excreted to a slight extent . An ANOVA analysis was realized to rest the effect of the site, flooded or not, the species and the period. There was no site effect; however, we not ed significant differences between species for calcium, magnesium and phosp hate. These differences are discussed according to the physiological state of the species and environmental conditions. ((C) Academie des sciences / E lsevier, Paris.)