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Title: Shore and mid-channel surveys reveal distinct phytoplankton-bacterial population associations along an urban estuary
A growing body of literature has highlighted the importance of phytoplankton-bacterial associations to marine and estuarine ecological and biogeochemical function, but their population linkages remain sparsely characterized within urban estuaries. Since many developed coastlines are heavily impacted by anthropogenic nutrient inputs, elucidating their phytoplankton-bacterial dynamics provides insight into nutrient cycling, productivity, and can help inform water quality management. This study compared surface (0.5 m depth) physical water quality, cell abundances of major phytoplankton taxa and bacteria, as well as concentrations of chlorophylla(chla) and dissolved organic matter (DOM) in the nitrogen (N)-enriched Western Long Island Sound (WLIS), USA, between mid-channel and shore sites (in 2020 and 2021). Shore bacterial and phytoplankton abundances as well as DOM concentrations (primarily dissolved organic N and carbon [DOC]), were significantly higher than mid-channel, especially during summer, indicative of terrestrial loading influencing microbial assemblages as well as N and C cycling. Abundances of key phytoplankton taxa were better indicators of bacterial abundances than chla, as bacterial abundances positively and significantly correlated with those of dinoflagellates, especially the most common generaProrocentrum(mid-channel, shore) andHeterocapsa(shore only), but not with diatoms. However, pennate diatom abundances negatively and significantly correlated with DOC concentrations in the mid-channel. Results highlight the impact of terrestrial inputs on WLIS microbial assemblage dynamics, presumably by favoring bacteria and dinoflagellate population coupling, as well as shed new ecological insight into how phytoplankton and bacterial communities respond to nutrient loadings in urban estuaries.  more » « less
Award ID(s):
2039867
PAR ID:
10541877
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Inter-Research
Date Published:
Journal Name:
Aquatic Microbial Ecology
Volume:
90
ISSN:
0948-3055
Page Range / eLocation ID:
121 to 139
Subject(s) / Keyword(s):
Algal-bacterial interactions dissolved organic matter DOC dinoflagellates phytoplankton Long Island Sound urban estuaries diatoms Prorocentrum harmful algal blooms
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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