par Herr, Céline;Chapuis, Lydie 
;Dassonville, Nicolas ;Vanderhoeven, Sonia ;Meerts, Pierre Jacques
Référence Journal of plant nutrition and soil science, 170, 6, page (729-738)
Publication Publié, 2007
;Dassonville, Nicolas ;Vanderhoeven, Sonia ;Meerts, Pierre Jacques Référence Journal of plant nutrition and soil science, 170, 6, page (729-738)
Publication Publié, 2007
Article révisé par les pairs
| Résumé : | Invasions by alien plants can alter biogeochemical cycles in recipient ecosystems. We test if Early Goldenrod (Solidago gigantea) alters P fractions. To that end, we compare invaded plots and adjacent, uninvaded resident vegetation for specific fractions of organic and inorganic P, phosphomonoesterase (PME) activity in topsoil, and immobilization of P in above-and belowground organs and in soil microbial biomass. Invaded plots had lower soil pH and 20%-30% higher labile P fractions (resin-Pi, bicarb-Pi, NaOH-Pi), and the difference was consistent across seasons. There was no difference in microbial P. Alkaline-PME activity was 30% lower in topsoil of invaded plots. Annual P uptake in aboveground phytomass was not markedly higher in Solidago. In contrast, P in belowground organs steadily increased in autumn in invaded plots, due to both increased biomass and increased P concentrations. This indicated higher net P immobilization in Solidago, far in excess of both resorption from senescing shoots and P requirements for aboveground biomass in subsequent year. Higher turnover rates of P in belowground organs and mobilization of sparingly soluble P forms through rhizosphere acidification may be involved in the observed differences in soil P status between invaded and uninvaded plots. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA. |
