15 N uptake by mycorrhizal native and invasive plants from a N-eutrophied shrubland: a greenhouse experiment

摘要: In the coastal sage scrub (CSS) community of southern California, Artemisia californica and other native shrubs are gradually being replaced by invasive annual grasses, especially Bromus madritensis ssp. rubens. This decline may be attributed, in part, to local atmospheric N deposition, which causes elevated soil NO3 −. Unaffected soils have low with a relatively higher concentration NH4 + than The objectives this study were: (1) compare short-term uptake 15NO3 − 15NH4 B. A. (2) discern whether or is influenced mycorrhizal status either plant species. Analysis 15N concentrations indicated that both took up more +, but overall, 6–15 times forms californica. Mycorrhizal had an increased roots not shoots. madritensis, only response was reallocation −, plants retaining proportion roots. Overall, arbuscular mycorrhizae small effect on study. However, ability take so much explain part why it has been successful replacing CSS.