IS TEMPORAL OCCURRENCE OF DIATOMS RELATED TO SPECIES TRAITS, LOCAL ABUNDANCE, AND REGIONAL DISTRIBUTION?¹

Abstract

Water quality in streams typically changes fast, and sensitive biological indicators are crucial for monitoring these changes in water quality. Diatoms are widely used in biological stream quality assessment. However, interannual and intra-annual variation of diatom population densities is large, often hampering a reliable quality assessment. We studied the importance of different species traits on temporal occurrence of diatom species. We also examined whether temporal occurrence of diatoms is related to species' local abundance or regional distribution using a data set collected in Finnish streams. According to the general linear model (GLM), temporal occurrence of diatoms increased with increasing local abundance and regional distribution. Species that occurred more frequently also had larger niche breadths and nonmarginal niche positions. In addition, cell size and attachment ability were positively related to species temporal occurrence. Our results imply that abundant and widely distributed species with large niches and ability to attach sustain persistent populations in varying environmental conditions typical for streams. We suggest that future studies could concentrate on monitoring these common (abundant) species when detecting the possible changes in the biological state of streams. We advise, however, to consider a relatively large number of species as many of the most common species may have low indicator values.

Microbial mats as shelter microhabitat for amphipods in an intermittent karstic spring

“…As one of the most widely recognized freshwater diatoms, A. minutissimum, a species corresponding to a still largely unresolved species complex, is frequently dominating benthic algal communities in the upper courses of streams and rivers (Virtanen et al, 2011;Noga, 2012;Novais et al, 2015;Cyr, 2016). Despite its omnipresence and importance in water quality assessments, A. minutissimum is attributed to a rather difficult identification due to small cell size, inter-and intraspecific varieties and insufficiently studied ecology (Potapova and Ponader, 2004;Ponader and Potapova, 2007;Novais et al, 2015).…”

The Influence of Selected Factors on the Distribution of Epilithic Diatoms in a Torrential River the Kamniška Bistrica (Slovenia)

“…4). These taxa have the ability to attach fi rmly to substrata, which increases the temporal occurrence of these diatoms (VIRTANEN et al 2011). Authors from different parts of the world report that A. minutissima is one of the most frequent taxa in epilithic diatom communities in running waters (HOFFMAN et al 2011, SOLTANPOUR-GARGARI et al 2011, VIRTANEN et al 2011, mainly because of the wide ecological amplitude, making it a pioneer taxon.…”

“…Benthic diatoms are frequently used for evaluating the ecological status of running waters (VIRTANEN et al 2011), since they are various, dominant in phytobenthos, and since the ecological preferences of several species are well known (BELTRAMI et al 2012). Habitat and species diversity of biotic communities in running waters are strongly infl uenced by the properties of the catchment area, land use and pollution sources.…”

The roles of environment and space in shaping stream diatom communities

“…Four diatom species were especially typical for the Kymijoki basin (see Table 3), including Achnanthes minutissima. This species is very abundant and widely distributed (Virtanen et al, 2011).…”

“…Benthic diatoms have been found to be useful for stream monitoring in several countries (Lavoie et al, 2010;Besse-Lototskaya et al, 2011;Smucker & Vis, 2011b), including Finland, e.g. by Eloranta & Soininen (2002), Soininen & Ko¨no¨nen (2004) and Virtanen et al (2011).…”