Chapter 1 - Núria BONADA

Regional amd local scale: convergences and divergences
others, it was recorded as a disimilarity, whereas when a family display a similar affinity in
both regions it was recorded as a similarity. Thereby, and according to Figure 9, the highest
percentage of similarity is shown between South Africa and SWAustralia, indicating that
common taxa with high indicator values display a similar pattern in both regions.
Consequently, 94.4% of the common and abundant taxa between South Africa and
SWAustralia present a similar response to the permanency and temporality. On the other
hand, MedBasin and SWAustralia also show a high similarity, compared with the rest of
paired-comparisons. In fact, California and MedBasin, even though sharing more families with
a high IV-value than the other regions only 54.2% of the taxa display a similar segregation in
permanent and temporary sites.
Habitat effects
In Figure 10 the cluster using all common taxa in sampled med-regions is presented.
Differences between regions are higher than between habitats in South Africa and SWAustralia
Cali+Med
L
SWAustralia
RL
South Africa
RL
Cali+Med
R
Figure 10. Bray-Curtis cluster with common matrix and riffles and pools reference sites.
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