The small scale spatial pattern of C3 and C4 grasses depends on shrub distribution
Abstract: At micro-site scale, the spatial pattern of a plant species depends on several factors including interactions with neighbours. It has been seen that unfavourable effects generate a negative association between plants, while beneficial effects generate a positive association. In grasslands, the presence of shrubby species promotes a particular microenvironment beneath their canopy that could affect differently the spatial distribution of plants with different tolerance to abiotic conditions. We measured photosynthetic active radiation, air temperature and wind speed under shrub canopies and in adjacent open sites and analysed the spatial distribution of four grass species [two C3 and two C4] in relation to shrub canopy in a grazed sub-humid natural grassland in southern Uruguay. Radiation, air temperature and wind speed were lower under shrubs than in adjacent open sites. The spatial distribution of grasses relative to the shrub canopy varied depending on the photosynthetic metabolism of grasses. C4 grasses showed a negative association or no correlation with the shrubs, whereas C3 grasses showed a positive association. Our results highlight the importance of the photosynthetic metabolism of the grasses in the final outcome of interactions between grasses and shrubs. Micro-environmental conditions generated underneath shrubs create a more suitable site for the establishment of C3 than for C4 grasses. These results show that facilitation could be more important than previously thought in sub-humid grasslands.
| Main Authors: | , , |
|---|---|
| Format: | Texto biblioteca |
| Language: | spa |
| Subjects: | AIR TEMPERATURE, C3 PLANT, C4 PLANT, CANOPY ARCHITECTURE, FACILITATION, GRASS, GRASSLAND, NEGATIVE INTERACTIONS, PHOTOSYNTHETICALLY ACTIVE RADIATION, POACEAE, POSITIVE INTERACTIONS, SHRUB, SHRUBS, SOUTH AMERICA, SPATIAL DISTRIBUTION, SUB-HUMID GRASSLAND, URUGUAY, VEGETATION STRUCTURE, WIND VELOCITY, |
| Online Access: | http://ceiba.agro.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber=47078 http://ceiba.agro.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber= http://ceiba.agro.uba.ar/cgi-bin/koha/opac-detail.pl?biblionumber= |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|