The role of the environment in the distribution and composition of Trichoptera assemblages in streams

Abstract

We investigated how diversity and distribution of more than 11000 Trichoptera larvae in streams of central Portugal were related to chemical and physical environmental variables. Sixty-six sites were sampled in 2001, by kicknet, in 55 streams of the Mondego River basin, the largest entirely Portuguese river. Simultaneously 43 environmental variables were evaluated for each site. We identified 18 families and 70 species and genera of caddisflies, representing ≈ 20 % of all trichopteran taxa recorded for the Iberian Peninsula. The species Calamoceras marsupus, Cheumatopsyche lepida, Hydropsyche bulbifera, Hydropsyche siltalai, Hydroptila sp., Lepidostoma hirtum, Mystacides azurea, Chimarra marginata, Polycentropus flavomaculatus, Tinodes waeneri, Rhyacophila adjuncta and Sericostoma sp. were found to be the most important taxa in the Mondego River basin. Stream order, substrate quality, altitude, current velocity and alkalinity explained 41 % of the taxa distribution suggesting that at a wider (catchment) scale physical and hydrological parameters are more important for the distribution of Trichoptera assemblages than chemical parameters. Six significantly different groups of sites with similar Trichoptera assemblages were identified in the catchment and related to altitudinal, hydrological and substrate gradients. Our findings allow us to predict Trichoptera assemblages in streams of the Mondego catchment based on few environmental characteristics.

Environmental factors prevail over dispersal constraints in determining the distribution and assembly of Trichoptera species in mountain lakes

“…This reflects that M. azurea has a strong dependence on vegetal material for case building, whereas the widespread A. pyrenaea may use both vegetal pieces and mineral grains, as observed in our samples. Accordingly, Feio et al (2005) found a positive association between woody vegetation and M. azurea populations in the Mondego River basin (central Portugal). In contrast with the previous species cases, the distribution of P. laetabilis and P. flavomaculatus agrees between lakes and streams.…”

“…Accordingly, Feio et al. (2005) found a positive association between woody vegetation and M. azurea populations in the Mondego River basin (central Portugal).…”

Diversity, distribution, and conservation of the Trichoptera and their habitats in north‐eastern Algeria

“…shown by numerous studies (Wiberg-Larsen et al, 2000;Resh, Reynoldson & Rosenberg, 2002;Feio et al, 2005). In contrast, in some possibly degraded watercourses water chemistry, particularly pH and water hardness, may play a major role (Ormerod & Edwards, 1987;Lock & Goethals, 2012).…”

“…The Oum El Bouaghi region may be representative of the whole Algerian Hauts Plateaux, an area where caddisfly diversity might be Both eastern and western Aurès differed in current velocity, bed width, and land use, and macroinvertebrates are expected to respond differentially to these environmental features (Resh, Reynoldson & Rosenberg, 2002;Feio et al, 2005). We also expect that these two assemblages may be found across the whole Saharan Mountain range, from western Tunisia to Tlemcen and eastern Morocco, with environmental conditions such as geology, land use, and hydrology modulating species composition and abundance.…”

Are Water Framework Directive stream types biologically relevant? The case of the Mondego river, Portugal

“…3 in Chaves et al, 2005). Between-site natural variability in Trichopteran assemblage structure (Feio et al, 2005) and overall macroinvertebrate community structure of the Mondego River basin (Chaves et al, 2005) have been shown to be related primarily to altitude and conductivity (alkalinity). Thus large-scale variables used for stream typology employed in this study seem to include some of the local spatial variation in the Mondego River basin, which may be the reason for the significant differences between DA centroids of different stream types.…”