DOI: 10.5061/dryad.8cz8w9gpf
title: A trait‐based approach predicting community assembly and dominance of microbial invasive species

description: Understanding the mechanisms underlying community assembly helps to define
 success and susceptibility to biological invasions. A methodological
 approach to this aim is to use trait-based approaches. Under the
 hypothesis that the morphology-based functional groups (MBFG) clusters
 species with similar niche we analyse how trait-related differences in
 fitness influence the outcome of invasion. The invasive dinoflagellate
 Ceratium furcoides (CF) can be used as the model species considering its
 morphological (e.g. volume) and physiological traits (e.g. growth rates)
 comparing with species from the same (MBFG V) and different (MBFG VII:
 colonial cyanobacteria) MBFG. Here we present the information needed to
 apply this approach with similar or different questions including
 information from two aquatic environments from South America: the first
 one located in Argentina (Miní flood-plain Lake) and the second one in
 Uruguay (Salto Grande Reservoir). Phytoplankton morphological traits
 measured from field samples, along with richness, abundance, biovolume and
 environmental variables are presented. Phytoplankton individuals and
 species are classified in terms of MBFG and focus on the invasive species
 Ceratium furcoides. The literature derived information includes growth
 rates with temperature for phytoplankton species classified in MBFG V
 including Ceratium furcoides.
description: <b>Study area and sampling
 design</b> Two contrasting ecosystems are considered, a
 large human-made reservoir (Salto Grande) and a natural floodplain lake
 (Miní Lake) (Figure 1: location of sampling sites in both ecosystems).
 Salto Grande is a eutrophic freshwater reservoir with low flushing rate
 and an area of 783 ha (Martínez de la Escalera et al. 2017, Kruk et al.
 2017) where samples were taken bimonthly in six occasions (January 2013 -
 March 2014), including littoral and open water samples (n = 12). The Miní
 Lake is located within the Paraná River floodplain and is permanently
 connected to the river, modulated by hydrological and sedimentological
 pulses of the fluvial system (Mayora et al. 2013). In Miní Lake, samplings
 were carried out approximately fortnightly from November 2009 to December
 2010, and from January to December 2012 (n = 38).
 At each sampling occasion,
 temperature (°C) and depth (m) were measured. Qualitative samples for
 phytoplankton analysis were taken with 25 μm
 mesh-size plankton net and fixed with carbonate formaldehyde 4%.
 Phytoplankton samples for counting were taken with Niskin bottles and
 fixed in acid lugol solution (1%). Zooplankton samples in Salto Grande
 Reservoir were obtained by filtering 10 to 20 litres of water with a 50 µm
 mesh and were fixed with acid lugol solution (1%). Counting was done
 following Paggi and José de Paggi (1974) in Sedgewick-Rafter chambers.
 Zooplankton species were classified into rotifers, cladocerans and
 copepods. Phytoplankton abundance (organisms
 mL<sup>-1</sup>) was counted using settling chambers (Utermöhl
 1958), at several magnifications (10 to 1000×) until reaching at least 100
 organisms of the most frequent species (Lund et al. 1958). Organism
 dimensions, including maximum lineal dimension (MLD,
 μm) were measured. Individual volume (V,
 μm<sup>3</sup>) and surface area (S,
 μm<sup>-1</sup>) were calculated
 according to Hillebrand et al. (1999). The presence of flagella, aerotopes
 and mucilage was noted for each organism. Based on their individual
 morphological traits each organism was classified into one of seven
 morphology-based functional groups (MBFG: I-VII) (Kruk et al. 2010, Kruk
 and Segura 2012). Biovolume (mm<sup>3</sup>
 L<sup>-1</sup>) was used as a metric of biomass and was
 calculated by multiplying each organism individual volume by its
 abundance, all organisms of the same sample were combined to calculate
 total phytoplankton biovolume and the same was performed for each of the
 MBFG. Species richness was estimated in each sample after identifying all
 organisms to the species level, when possible.
 <i><b>Literature review for
 temperature response
 growth</b></i>
 Information from controlled
 experiments designed to quantify population growth rates of <i>C.
 furcoides</i> (n = 13, Butterwick et al. 2005) and MBFG V
 representatives as a function of temperature (n = 89) as well as for MBFG
 VII (Kruk et al. 2017). Only data from single-species cultures with
 unlimited nutrients and saturating light conditions were
 considered.
 <strong>References</strong> Butterwick, C. et al. 2005. Diversity in the influence of temperature on the growth rates of freshwater algae, and its ecological relevance. – Freshwater Biol. 50: 291–300. doi 10.1111/j.1365-2427.2004.01317.x Hillebrand, H. et al. 1999. Biovolume calculation for pelagic and benthic microalgae. – J. Phycol. 35: 403–424. 10.1046/j.1529-8817.1999.3520403.x Kruk, C. and Segura, A.M. 2012. The habitat template of phytoplankton morphology-based functional groups. – Hydrobiologia 698: 191–202. Kruk, C. et al. 2010. A morphological classification capturing functional variation in phytoplankton. Freshwater Biol. 55: 614–627. Kruk, C. et al. 2017. A multilevel trait-based approach to the ecological performance of Microcystis aeruginosa complex from headwaters to the ocean. – Harmful Algae 70: 23–36. doi: 10.1016/j.hal. Lund, J.W.G. et al. 1958. The inverted microscope method of estimating algal numbers and the statistical basis of estimations by counting. – Hydrobiologia 11: 143–170. Martínez de la Escalera, G. et al. 2017. Dynamics of toxic genotypes of Microcystis aeruginosa complex (MAC) through a wide freshwater to marine environmental gradient. – Harmful Algae 62: 73–83. doi: 10.1016/j.hal.2016.11.012 Mayora, G. et al. 2013. Spatial variability of chlorophyll-a and abiotic variables in a river–floodplain system during different hydrological phases. – Hydrobiologia 717: 51–63. doi: 10.1007/s10750-013-1566-x Paggi, J. C. and José de Paggi, S. J. 1974. Primeros estudios sobre el zooplancton de las aguas lóticas del Paraná medio. – Physis 33: 91–114. DOI: 10.14409/fabicib.v18i0.4853 Utermöhl, H. 1958. Zur Vervollkommnung der quantitativen Phytoplankton-Methodik: Mit 1 Tabelle und 15 abbildungen im Text und auf 1 Tafel. – Int. Ver. Theor. 9: 1–38.
description: Table 1 contains
 phytoplankton total biovolume
 (μm<sup>3</sup>ml<sup>-1</sup>), <i>Ceratium
 furcoides</i> biovolume and species richness (S) in different
 sampling dates of Miní Lake (Argentina). The same variables are included
 in for Salto Grande reservoir (Uruguay) in Table 2.
 Occurrence and value of
 phytoplanktonic individual volume (μm<sup>3</sup>) in
 different sampling dates of Miní Lake (Argentina) are included in Table 3
 along with environmental variables. Here the individual volume was
 estimated as an average among all sites for all species except for
 <i>Ceratium furcoides</i> that was measured in each sampling
 occasion. Similar information with greater detail is included for the
 Salto Grande reservoir in Table 4. For this ecosystem all organisms were
 measured in all samples and morphological traits are calculated at the
 level of the organisms in each sample (V, S and MLD). Therefore, biovolume
 was also estimated individually by multiplying the individual volume by
 the individual abundance in the sample estimated from counts (please refer
 to the methods section). Table 4 also includes environmental drivers in
 different sampling dates and sites of Salto Grande reservoir including
 depth (z, m), temperature (T, <sup>o</sup>C), flushing (f,
 d<sup>-1</sup>) and the abundance of zooplankton is clustered
 in rotifers, cladocera and copepods abundance.
 Finally, in Table 5 we
 included the growth rates with temperature for phytoplankton species from
 morphology-based functional group (MBFG) V including <i>Ceratium
 furcoides</i> (CF). The taxonomic group and references are also
 included.