Phosphate uptake in arctic plants in relation to phosphate supply: the role of spatial and temporal variability [Carex aquatilis, Eriophorum vaginatum, Ledum decumbens, Loiseleuria procumbens, Salix pulchra, Aulacomnium turgidum, Carex bigelonii, Salix glauca, Sphagnum rubellum, Cetraria richardsonii, Cladina rangiferina]

absorption de substances nutritives alaska arbuste arbustos arctic tundra betula nana carex comunidades vegetales crecimiento croissance disponibilidad de nutrientes especies fertilidad del suelo fosforo growth lichen lichenes meadows nutrient availability nutrient uptake phosphore phosphorus plant communities prados de siega prairie de fauche salix seasonal variation shrubs soil fertility species sphagnum toundra arctique tundra artica