Environmental factors, spatial variation, and specific requirements of Chironomidae in Mediterranean reference streams

Abstract

Abstract. Chironomidae spatial distribution was investigated at 63 near-pristine sites in 22 catchments of the Iberian Mediterranean coast. We used partial redundancy analysis to study Chironomidae community responses to a number of environmental factors acting at several spatial scales. The percentage of variation explained by local factors (23.3%) was higher than that explained by geographical (8.5%) or regional factors (8%). Catchment area, longitude, pH, % siliceous rocks in the catchment, and altitude were the best predictors of Chironomidae assemblages. We used a k-means cluster analysis to classified sites into 3 major groups based on Chironomidae assemblages. These groups were explained mainly by longitudinal zonation and geographical position, and were defined as 1) siliceous headwater streams, 2) mid-altitude streams with small catchment areas, and 3) medium-sized calcareous streams. Distinct species assemblages with associated indicator taxa were established for each stream category using IndVal analysis. Species responses to previously identified key environmental variables were determined, and optima and tolerances were established by weighted average regression. Distinct ecological requirements were observed among genera and among species of the same genus. Some genera were restricted to headwater systems (e.g., Diamesa), whereas others (e.g., Eukiefferiella) had wider ecological preferences but with distinct distributions among congenerics. In the present period of climate change, optima and tolerances of species might be a useful tool to predict responses of different species to changes in significant environmental variables, such as temperature and hydrology.

Environmental factors – spatial and temporal variation of chironomid communities in oceanic island streams (Azores archipelago)

“…An understanding of both local and large-scale environmental factors is vital in order to assess the importance of their role in structuring chironomid communities (Punti et al, 2007;Calle-Martı´nez and Casas, 2006;Punti et al, 2009). Differences in chironomid assemblage structure between islands were not apparent (P = 0.068) but were significantly different along the lotic longitudinal gradient (P = 0.004).…”

“…Rosenberg and Resh, 1993;Wilson and Ruse, 2005;Raunio et al, 2007b;Raunio et al, 2007a;Heino and Paasivirta, 2008). Further, studies relating environmental variables to the spatial and/or temporal patterns of chironomid distribution are reported from Australia (Hardwick et al, 1995;Dimitriadis and Cranston, 2007), Finland (Raunio et al, 2007b;Heino and Paasivirta, 2008), the United Kingdom (Ruse and Wilson, 1995;Ruse, 2000;Ruse and Davison, 2000), Spain (Calle-Martı´nez and Casas, 2006;Punti et al, 2009) and Japan (Inoue et al, 2005). The association between the environmental variables that determine chironomid community structure is complex, determined by physical, chemical and biological processes that vary both temporally and spatially in the lotic environment.…”

Responses of Chironomid larvae (insecta, Diptera) to ecological quality in Mediterranean river mesohabitats (South Italy)

“…), except for Eukiefferiella brevicalcar (usually > 550 m a.s.l., e.g. Puntì et al, 2009), which was excluded by PCA as rare taxon. PCA axes 3 and 4 accounted for a small part of the total variance (respectively 10.7% and 7.9%) and were positively correlated to catchment area and distance from source, being associated with the slight upstreamdownstream gradient.…”

Índice de calidad ecológica con base en macroinvertebrados acuáticos para la cuenca del río Negro (ICERN-MAE), Colombia

“…Un caso particular y ampliamente discutido es el de la clasificación de los organismos de Chironomidae hasta el nivel de familia, con la consecuente utilización de dicha familia como indicadora de aguas fuertemente contaminadas (Alba-Tercedor, 1996;Riss et al, 2002b;Roldán, 2003), lo cual ha sido considerado erróneo en varios casos (McGill, Wilson & Brake, 1979;Puntí, Rieradevall & Prat, 2009;Al-Shami, Rawi, Hassan Ahmad & Nor, 2010). En este trabajo se constató que ciertamente los integrantes de Chironomidae colectados abarcaron toda una gama de condiciones ecológicas, Chironomus tuvo una puntuación óptima de 4.4, que indica condiciones críticas; Polypedilum y Orthocladiinae morfoespecie 1, mostraron puntuaciones asociadas a condiciones regulares; mientras que Parachironomus, Endotribelos y Paratanytarsus entre otros, presentaron puntuaciones indicadoras de buen estado ecológico.…”