Phytoplankton assemblages in a complex system of interconnected reservoirs: the role of water transport in dispersal

Abstract

Phytoplankton in a complex network of reservoirs for drinking water supply was sampled in the dry and flood seasons to understand the role of dispersal through hydrochory and of environmental filters in determining the phytoplankton abundance and composition. The main assumptions tested in the present study are that (i) phytoplankton structure in these waterbodies is strongly dependent on the transportation with the river waters flowing through them and (ii) the importance of this stochastic transportation is decreasing as the connectivity with the river decreases allowing environmental filters to shape phytoplankton structure. The multivariate analysis showed that although phytoplankton was inoculated largely by Pearl River water inputs and inflow among the system, the hydraulic architecture of the reservoir network shaped and modulated the composition and abundance of phytoplankton.

Ecological importance of rare phytoplankton species revealed by their high contribution to unsaturated fatty acids in tropical waters

“…S. obliquus was not completely excluded by cyanobacteria in all the studied waterbodies and this may have improved the food quality for consumers under cyanobacteria dominance. In tropical waters as a whole, highly dynamic hydrological conditions and high temperature allow more rare species to co-exist under cyanobacteria dominance (Hu et al, 2017;Xu et al, 2022). The overall role of rare phytoplankton species may, therefore, be more important than generally considered and warrants further studies.…”

Preface: Emerging trends in aquatic ecology II

“…All of these studies focussed on passively dispersed microalgae and zooplankton. In particular, Zorzal-Almeida et al (2017) analysed the relative contribution of environmental heterogeneity, spatial extent and productivity in determining the b-diversity of benthic diatoms in tropical reservoirs, whereas phytoplankton diversity patterns were studied in two sets of subtropical reservoirs in South-America and Asia (Hu et al, 2017;Wojciechowski et al, 2017). Marrone et al (2017) reviewed the diversity patterns of calanoid copepods in the different limnoregions of the West Palaearctic and performed a biogeographical analysis revealing two different post-glacial colonization patterns in the Western and Eastern part of the Mediterranean Basin, most likely depending on the different orientation of the main mountain ranges in that region.…”

Everything is not everywhere: can marine compartments shape phytoplankton assemblages?

“…The role of physical barriers as drivers of plankton assemblage structure has traditionally been investigated in lakes, salt lakes, rivers and interconnected reservoirs [13][14][15][16][17]. In these systems, the dispersal of organisms is limited or facilitated by processes such as wind [18], directional riverine flow [19,20], pipelines connecting artificial reservoirs [15] and animal transport [21]. In these contexts, evidence suggests that species sorting according to local environmental conditions is the prevailing mechanism driving assemblage composition, whereas dispersal limitation becomes important only at large scales of the order of thousands of kilometres [16,17].…”

“…The role of physical barriers as drivers of plankton assemblage structure has traditionally been investigated in lakes, salt lakes, rivers and interconnected reservoirs [13][14][15][16][17]. In these systems, the dispersal of organisms is limited or facilitated by processes such as wind [18], directional riverine flow [19,20], pipelines connecting artificial reservoirs [15] and animal transport [21].…”