Diversity patterns and food web structure in a Mediterranean intermittent stream

Abstract

In this work we present the results of a one-year study on the macroinvertebrate community in an intermittent stream in southern Spain. We have studied the taxonomic composition, diversity and food web monthly in order to consider temporal variability in these parameters. More than 60 macroinvertebrate taxa have been recorded in the stream, but they do not cohabit at the same time. Many of them join the community at the beginning of the wet period. Afterwards, some new taxa incorporate but some others disappear. This leads to huge fluctuations in the diversity of the community and in the food web of different sampling dates. These variations are linked to environmental disturbances, mainly to flow peaks and minimums. From a relatively well structured, but simple, food web at the beginning of the wet period, it can be seen how several trophic levels disappear with time, and how several organisms change or extend their trophic function within it. We relate these variations to the intermediate disturbance hypothesis and discuss the resilience of the community of this intermittent stream.

Interplay of hydrology, community ecology and pollutant attenuation in the hyporheic zone

“…These systems are common worldwide and support diverse communities of aquatic organisms including many taxa that survive in dry riverbeds and/or rapidly recolonize when water returns (Stubbington & Datry 2013. Indeed, the influence of drought may be even more intense in streams that lack a marked seasonally (unpredictable intermittent streams, López-Rodríguez et al 2012). This is the case for some Mediterranean streams with supra-seasonal drought, where many organisms that survived in the HZ during the dry season recolonized the stream during the first month of the wet season (López-Rodríguez et al 2012).…”

“…Indeed, the influence of drought may be even more intense in streams that lack a marked seasonally (unpredictable intermittent streams, López-Rodríguez et al 2012). This is the case for some Mediterranean streams with supra-seasonal drought, where many organisms that survived in the HZ during the dry season recolonized the stream during the first month of the wet season (López-Rodríguez et al 2012). Use of the HZ as a refuge is not exclusive to large biota, it occurs across a wide range of organism size.…”

The effect of large predators on the decomposition rate and the macroinvertebrate colonization pattern of leaves in a Mediterranean stream

“…Chironomidae use to dominate the invertebrate fauna in terms of absolute numbers in many freshwater systems (Brittain, ; Ferrington, ; Ferrington, Berg, & Coffman, ) and particularly in streams from the Iberian Peninsula (e.g., López‐Rodríguez, Peralta‐Maraver et al, ; Oscoz, Galicia, & Miranda, ; Vannucchi, Peralta‐Maraver, Tierno de Figueroa, & López‐Rodríguez, ), such as the one we studied. Baetidae uses to be another dominant group in many streams and rivers (see previous references), but in our reach, this group is surpassed by other families, such as Ephemerellidae, Elmidae, and Leuctridae.…”

Spatial and seasonal variability in the trophic role of aquatic insects: An assessment of functional feeding group applicability

“…Bo, Fenoglio, López‐Rodríguez, & Tierno de Figueroa, ; López‐Rodríguez et al., ; Tierno de Figueroa et al., ) and the food web of benthic fauna in Mediterranean streams (e.g. López‐Rodríguez et al., ; Peralta‐Maraver, López‐Rodríguez, & Tierno de Figueroa, ; Vannucchi, López‐Rodríguez, Tierno de Figueroa, & Gaino, ; Vannucchi, Peralta‐Maraver, Tierno de Figueroa, & López‐Rodríguez, ).…”