Chapter 1 - Núria BONADA

Chapter 5
Results from the 4 th Corner Method show several significant patterns in between biological
traits from permanent, intermittent and ephemeral streams (Table 2). A mix of behavior
features seems to be present in permanent sites (as no significant traits are shown), while
some specific ones are exclusive from intermittent and ephemeral situations, independently.
However, “Maximal size”, “Reproduction”, “Resistance forms” and “Feeding habits” are not
significant in any category, in contrast to “Life cycle duration”, “Potential number of
reproductions per year”, “Aquatic stages”, “Dispersal”, “Respiration”, “Locomotion and
substrate relation” and “Food”. In intermittent sites “Life cycle duration” is significantly over
than 1 year with several reproductions per year, and its community is dominated by flying,
swimmer or surface swimmer adults with aerial respiration and an active and by air
dispersion. In contrast, ephemeral sites are dominated by larvae that breath by gills or
tegument and are attached on the substrate. Their dispersion is by water and has short life
cycle duration (lower than one year) and few reproductions per year. Food appears significant
in ephemeral sites, with larvae feeding in fine sediment or detritus.
Table 2. Results of the 4 th Corner Program, for each biological trait tested and flow category. The most
significant traits are indicated with * (p