Bibliographic Detail
Ní Chatháin, B. & Harrington, T.J., 2008
Reference:
Ní Chatháin, B. & Harrington, T.J. (2008). Benthic diatoms of the River Deel: diversity and community structure. Biology and Environment: Proceedings of the Royal Irish Academy 108B: 29-42.
Abstract:
This paper compares the diversity and structure of the benthic diatom assemblages on boulder and
cobble substrata and examines the influence of site and seasonal factors on diatom diversity in the
River Deel, Co. Limerick. One hundred and ten diatom species were identified from the River
Deel, with 85 species found on boulders over a two-year period and 102 species found on cobbles
over a one-year period. There was little difference in the composition of the diatom community on
boulders between sites. Some differences were noted between sites for cobbles, with a small number
of species being more associated with certain sites than others. The absence of marked differences
between the sites was attributed to the lack of longitudinal variation in the main channel of the River
Deel. On both substrates, indicator species analysis showed that the abundance of most diatom
species was not related to sampling date. On boulders, only fourteen species in 1999 and twenty-one
species in 2000 had a significant association with any sampling date. Twelve cobble species had a
significant association with a sampling date (principally May). There was little correspondence
between significant indicator species on cobbles and boulders. The patterns of dominance of diatom
species differed between the boulder and cobble substrates over the sampling period, and Detrended
Correspondence Analysis (DCA) showed that diatom samples formed two distinct groupings based
on substrate.