A trait‐based approach predicting community assembly and dominance of microbial invasive species

Abstract

Understanding the mechanisms underlying community assembly helps to define success and susceptibility to biological invasions. Here, we explored phytoplankton community assembly following niche and neutral paradigms and using a trait-based approach. Under the hypothesis that the morphology-based functional groups (MBFG) clusters species with similar niche, we analysed how trait-related differences in fitness influence dominance of an invasive species. This was based on literature review, field data and model simulations. We predict that invading species can be dominant if: 1) do not belong to the local MBFG but use unexploited areas of the niche, or 2) belong to the resident MBFG but exhibit a higher fitness due to a particular combination of traits. The invasive dinoflagellate Ceratium furcoides was used as the model species to evaluate these hypotheses, its morphological (e.g. volume) and physiological (e.g. growth rates) traits were compared with species from the same (V: photosynthetic flagellates) and different (VII: colonial cyanobacteria) MBFG. Fitness was estimated using models parametrized with MBFG rates (R*, ability to draw down phosphate) under different environmental conditions (i.e. flushing). Results contributed to support both hypotheses. First, the alternation of C. furcoides and cyanobacteria dominance was explained by the use of different niches. Secondly, species from MBFG V were dominant under similar environments. Within this group V C. furcoides showed higher fitness under low flushing and high predation, advantage provided by a distinctive combination of traits. The application of trait-based approaches to represent the niche and estimate fitness along environmental gradients was useful to evaluate community assembly and can be used to predict the dominance of microbial species invasions.

First report of the invasive Ceratium furcoides (dinoflagellate) in Paracambi Reservoir, Rio de Janeiro: Risks to the world's largest domestic water treatment plant

“…furcoides were absent. The data from the present study, however, are not sufficient to support the suggestion of an alternation between these phytoplankton taxa (Kruk et al, 2021; Roriz et al, 2019), nor their coexistence in the environment (Reynolds et al, 2002). Further, the physical, chemical and consequently biological variability exhibited marked changes attributable to rainfall in a typical run‐of‐the‐river shallow reservoir such as Paracambi (Branco et al, 2019).…”

Effect of Grazing Treatments on Phenotypic and Reproductive Plasticity of Kobresia humilis in Alpine Meadows of the Qinghai-Tibet Plateau

“…Our results showed that K. humilis developed adaptive strategies in response to different grazing disturbances, with significant differences observed in monocot biomass and material partitioning patterns among the different grazing treatments. The plants improved their adaptation to grazing by adjusting resource allocation to occupy a favorable ecological niche in a continuously disturbed environment (Kruk et al, 2021). In our study, the S+Y treatment resulted in the highest biomass per plant, while the Y treatment showed the lowest biomass per plant.…”

Ecological modelling approaches for predicting emergent properties in microbial communities

“…Whereas the classic ecological models typically assume a constant environment, trait-based models focus on community dynamics along major environmental gradients. The system dynamics created by interaction between various ‘guilds’ and their environment may lead to a functional trait distribution that optimises a certain community-level functional property, such as nitrification in soil systems [ 110 , 111 ], organic matter decomposition [ 109 , 112 ], or resilience to invasion [ 113 ]. Trait-based models can elucidate the emergence of selection pressures and diversity patterns along modelled environmental gradients - important aspects to understanding evolutionary processes [ 114 , 115 ].…”