Plant species richness in a natural Argentinian matorral shrub-land correlates negatively with levels of plant phosphorus

Research output: Contribution to journalArticle

Abstract

The aim of this study was to ascertain whether there is a relationship between plant species richness and plant-available N, P and water in an environment subject to little anthropogenic disturbance. To accomplish this we studied the vegetation in matorral shrub-lands in northern Patagonia, Argentina. Due to the variation in slope, precipitation and aspect between the sites water status was determined using the C-12/C-13 fraction, delta C-13, to investigate whether this was a confounding factor. The numbers of herb, shrub, liana and tree species were determined at 20 sites along an estimated precipitation gradient. Leaf P and N content and the delta C-13 of Berberis buxifolia were determined, as well as the soil P and N content at the different sites. A negative correlation was found between species richness and Berberis buxifolia foliar P concentration (52% of the species richness variation was accounted for), and a positive correlation was found between plant species richness and Berberis buxifolia foliar N: P ratios (54% of the species richness variation was accounted for). The relationship between species richness and foliar P was seen when all layers of vegetation were included (trees, lianas, shrubs and herbs). Foliar N showed no correlation with species richness, while soil extractable NH4 showed a weak positive correlation with the number of shrub layer species (lianas, shrubs and trees). The species richness of the shrub layer increased with decreasing values of delta C-13. Low soil P availability thus affects local species richness in the matorral shrub-lands of Patagonia in Argentina although the growth of vegetation in the area has been shown to be limited by N. We suggest that low P levels increase plant species richness because low soil P concentration is associated with a high P partitioning and high potential for niche separation.

Details

Authors
  • Ylva-Li Blanck
  • Juan Gowda
  • Linda-Maria Mårtensson
  • Jakob Sandberg
  • Ann-Mari Fransson
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Zoology

Keywords

  • Available P, Available N, Species richness, C-13/C-12, Water, availability, Multiple resources, Andean mountains
Original languageEnglish
Pages (from-to)11-21
JournalPlant and Soil
Volume345
Issue number1-2
StatePublished - 2011
Peer-reviewedYes