Department of Environmental Resource Management, University College Dublin, Belfield, Dublin 4, Ireland
Subdominant species distribution in microsites around two life forms at a desert grassland-shrubland transition zone
Article first published online: 24 FEB 2009
2004 IAVS - the International Association of Vegetation Science
Journal of Vegetation Science
Volume 15, Issue 5, pages 615–622, October 2004
How to Cite
Hochstrasser, T. and Peters, D.P.C. (2004), Subdominant species distribution in microsites around two life forms at a desert grassland-shrubland transition zone. Journal of Vegetation Science, 15: 615–622. doi: 10.1111/j.1654-1103.2004.tb02303.x
Nomenclature: Anon. (1999).
- Issue published online: 24 FEB 2009
- Article first published online: 24 FEB 2009
- Received 9 January 2003; Accepted 22 March 2004
- Bouteloua eriopoda;
- Dominant plant;
- Functional group;
- Larrea tridentata;
- Shrub invasion;
- Spatial heterogeneity
Question: In the same landscape context — at a desert grassland-shrubland transition zone, how does subdominant plant abundance vary in microsites around dominant grasses and shrubs?
Location: Sevilleta LTER, New Mexico, USA (34°21’N; 106°53’W; 1650 m a.s.l.).
Methods: We compared the distribution of subdominant plants in canopy, canopy edge and interspace microsites around individual shrubs (Larrea tridentata) and grasses (Bouteloua eriopoda) at a transition zone that has been encroached by shrubs within the past 50 - 100 a. Plots of variable size according to microsite type and dominant plant size were sampled.
Results: Subdominant abundance was higher in microsites around L. tridentata shrubs than in microsites around B. eriopoda. Furthermore, differences in species abundance and composition were higher among microsites around grasses than among microsites around shrubs. The distribution of subdominants was mostly explained by their phenological characteristics, which indicates the importance of temporal variation in resources to their persistence.
Conclusions: This study of coexistence patterns around dominants revealed ecological contrasts between two dominant life forms, but other factors (such as disturbances) have to be taken into consideration to evaluate landscape-scale diversity.