Ecological background of diatom functional groups: Comparability of classification systems

Abstract

29 30Functional classification based on species traits brought a revolution in community ecology, 31and also boosted phytoplankton and in phytobenton (diatom) research. Several studies 32 stressed the usefulness of phytoplankton functional groups in ecological status assessment, 33and there is also a strong emphasis to use combined traits in ecological assessments of diatom 34 assemblages. The Combined Eco-Morphological Functional Groups (CEMFGs) help to reveal 35 species-environmental correlations, which can be hidden, controlling traits separately. between the correlations of CEMFGs-P or CEMFGs-RB and abiotic factors were 50 hypothesised in the case of those functional groups which contained reassigned taxa with high 51 frequency and/or abundance. Our results confirmed this hypothesis. Furthermore, the present 52 study also highlighted the relevance of well-defined trait classification. Abundant and/or 53 frequent taxa, which are able to change their life forms, can modify significantly the 54 relationship between the functional group containing them and environmental factors. In the 55 future, both field and laboratory studies should focus on revealing the circumstances, which 56 cause the mentioned changes in traits of diatoms. 57 58

Distribution of niche spaces over different homogeneous river sections at seasonal resolution

“…Downstream, however, the impact of the changes in physical environment becomes more dominant (Bolgovics et al, 2017;Abonyi, 2012). The positive loading of chloride in the first PCs (loading=0.7; Table 5a) indicate that one of the most dominant diatom species is a halophilic centric diatom (codon C), but this characteristic is also true of other planktic diatoms in the River Tisza and other watercourses as well (B-Béres et al, 2017;Table 2.). The greater the distance from the source, the greater the degree to which seasonality became the main driving force in the structuring of river phytoplankton community composition, with lower TIB-codon and higher J and Y codon ratio (Table 2).…”

Diversity and Structure of the Tychoplankton Diatom Community in the Limnocrene Spring Zelenci (Slovenia) in Relation to Environmental Factors

“…Planktonic species were positively correlated with the water level (τ = 0.497; Table 2), since a larger volume of water in the pool favours them. B-Béres et al [47] report that planktonic groups were positively correlated with temperature and nutrients.…”

“…Two pioneer species from the genus Amphora (A. inariensis and A. pediculus) were found in tychoplankton, while Achnanthidium minutissimum was the most abundant species. The reason for high abundance of benthic pioneer species in tychoplankton is their ability to be the fastest colonizers of bare substrate [47] adjacent to the microsprings which most frequently drift upwards into the water column before the late-successional high profile and motile species could out-compete them.…”

Measures and Approaches in Trait-Based Phytoplankton Community Ecology – From Freshwater to Marine Ecosystems

“…They are abundant in lakes, rivers and oceans alike, and play an important role in food webs and the biogeochemical cycles. As a result, their trait distribution and the consequences for diatom dynamics have been commonly studied in both ecosystem types (e.g., Terseleer et al, 2014;B-Béres et al, 2017;Taherzadeh et al, 2017). Diatoms come with the added advantage that they preserve in sediments and can thus be the focus of longer-term paleo-limnological or paleooceanographic analyses (Smol et al, 2005;McKay et al, 2012).…”