INVESTIGADORES
BIGATTI Gregorio
congresos y reuniones científicas
Título:
The inverse biodiversity gradient of rocky shore assemblages along the Argentinean coast.
Autor/es:
PALOMO, G; BIGATTI G.; M. BAGUR, J. L. GUTIERREZ & J.J. CRUZ-MOTTA.
Reunión:
Congreso; World Conference on Marine Biodiversity; 2011
Resumen:
Identifying
latitudinal patterns in species richness can be useful to predict biodiversity
changes due to climate change. As part of the activities of NaGISA (Census of
Marine Life) and the South American Research Group on Coastal Ecosystems, we sampled
the biodiversity of Argentinean rocky intertidal shores along 4700 km of coast. A
hierarchical nested design was used to sample seven locations separated by hundreds
of kilometers. Two sites separated 1 to 5 km were selected within each location. At
each site, the abundance of animals and algae was determined in 10 quadrats (0.25 m2) demarcated
at each of three shore levels (high, mid and low). Contrary to the general
postulate that the number of species decreases from tropics to poles, our data
shows a positive, significant linear relationship between species richness and
latitude. Biodiversity was impressively low, with only 104 species detected
along the entire region. Species richness increased from 17 species in the
northernmost sites (37º S) to 42 species in the southernmost ones (54º S). Understanding
the role of climate in determining this inverse biodiversity gradient will help
elucidate whether rising temperatures could lead to changes in species
distributional ranges and overall biodiversity losses toward the higher
latitudes.