Chapter 1 - Núria BONADA

Chapter 8
& Higler, 1992). Ecological profiles for macroinvertebrate taxa are required to test effectiveness
of biological indexes and to determine indicator species and autoecological information from
environmental conditions (Moretti & Mearelli, 1981). Indicator species have specific
requirements to several variables (Johnson et al., 1993) that can vary in a higher taxonomic
resolution (Resh & Unzicker, 1975; Cranston, 1990), and for this reason, several authors
suggest to take caution in the use of higher taxonomic levels in bioassessment methods (as
families) (e.g., Moog & Chovarec, 2000). Today, numerous controversies exist in literature in the
taxonomic sufficiency to be used because ecological patterns showed by species and families
may be similar using all the community (Furse et al., 1984; Marchant, 1990; Rutt et al., 1993;
Hewlett, 2000).
At family, species and individuals level, Trichoptera have been considered as an appropriated
group to assess water quality using larvae (e.g., see Resh, 1992; De Moor, 1999; Stuijfzand et
al., 1999; Bonada et al., Chapter 9) or adults (Malicky, 1981; Usseglio-Polatera & Bournaud,
1989). In a study in Luxembourg Rivers, Dohet (2002) found that Trichoptera were more
appropriated for bioassessment than Ephemeroptera, Coleoptera or Plecoptera. Factors as their
ubiquity, diversity, biological and ecological characteristics and the simplicity of their sampling
may explain this (Mackay & Wiggins, 1979; de Moor, 1999; Waringer & Graf, 2002). At family
and species levels, caddisfly have been related to several environmental variables displaying
some specific trends in ecological requirements (e.g., Dohet, 2002; Bonada et al., Chapter 7)
without establishing optimums and tolerance ranges. Caddisfly ecological profiles can be
obtained from literature from several ways. From one hand, studies performed in deformities
(Décamps et al., 1973; Petersen & Petersen, 1983; Camargo, 1991; Vuori, 1995; Vuori &
Kukkonen, 2002), asymmetries (Bonada & Williams, 2002) or toxicity tests (Greve et al., 1998)
may allow us to infer optimums and tolerances for a single species. On the other hand, studies
performed using large sets of field data including several species can also be useful (e.g., Gordon
& Wallace, 1975; Moretti & Mearelli, 1981; Herranz & García de Jalón, 1984; Verdonschot &
Higler, 1992; Stuijfzand et al., 1999; Kay et al., 2001). However, most of these studies usually
are done in small areas, with insufficient data, or without taking into account the abundance of
organisms, and thereby some cautions should be taken in extrapolating these results to other
areas or taxonomical levels.
In this study, caddisflies ecological profiles have been studied from field data obtained in
streams of the Iberian Mediterranean coast. Four factors make the caddisflies in this area an
ideal group to study their ecological profiles to water quality variables. Firstly, the high diversity
and endemicity of caddisfly in the Iberian Peninsula because interactions between ecological
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