Summary Global warming and eutrophication contribute to the worldwide increase in cyanobacterial blooms, and the level of cyanobacterial biomass is strongly associated with rises in methane emissions from surface lake waters. Hence, methane‐metabolizing microorganisms may be important for modulating carbon flow in cyanobacterial blooms. Here, we surveyed methanogenic and methanotrophic communities associated with floating Micr...

Bacteria play key roles in the function and diversity of aquatic systems, but aside from study of specific bloom systems, little is known about the diversity or biogeography of bacteria associated with harmful cyanobacterial blooms (cyanoHABs). CyanoHAB species are known to shape bacterial community composition and to rely on functions provided by the associated bacteria, leading to the hypothesized cyanoHAB interactome, a coe...

Rhizosphere microbiota has received much attention due to their associations with plant growth and their fundamental importance in terrestrial ecosystems. However, relatively few studies have focused on rhizosphere microbial communities associated with aquatic macrophytes in freshwater lakes. We hypothesized that the rhizosphere microbiome would reflect the presence of macrophyte roots and the concomitant microhabitat conditio...

Summary High‐throughput pyrosequencing of SSU rDNA genes was used to obtain monthly snapshots of eukaryotic and bacterial diversity and community structure at two locations in L ake T exoma, a low salinity lake in the south central U nited S tates, over 1 year. The lake experienced two disturbance events (i) a localized bloom of P rymnesium parvum restricted to one of the locations that lasted from J anuary to A pril, and (ii)...

Ecology Letters (2011) Abstract Blooms of Prymnesium parvum can severely harm fish and zooplankton, presumably through the release of allelopathic exotoxins that offer advantages for Prymnesium in its interactions with competitors and prey. We show that Prymnesium attaches to zooplankton and fish, causing mortality, whereas exposure of these organisms to Prymnesium across a permeable membrane does not cause mortality. We also...

Based on the premise that ecosystems with more species will function at more efficient rates, declining biodiversity is expected to alter important ecosystem functions, goods, and services across the globe. However, applicability of this general hypothesis to genetic or clonal richness in assemblages composed of few species is understudied. This illustrates the need to expand the focus of biodiversity–ecosystem‐function experi...

We examined effects of the invasive, toxigenic haptophyte Prymnesium parvum on grazing rates, feeding behaviors, and life‐history characteristics of clonal lineages of three daphniid zooplankton species. Grazing experiments revealed similar clearance rates for P. parvum and a common green alga. Behavioral observations revealed no significant effects of P. parvum on daphniid feeding behaviors after 30 min, but major declines in...

In a series of grazer‐gradient and dilution microcosm experiments, we compared grazing and nutrient mineralization by naturally co‐existing crustacean and microzooplankton assemblages from mesoeutrophic Lake Kinneret. Across two distinct seasonal plankton assemblages, microzooplankton dominated both phytoplankton and bacteria grazing and nitrogen (N) and phosphorus (P) mineralization. Mass‐specific ingestion rates by microzoop...

Competitive exclusion theory suggests that phytoplankton species number in an assemblage at equilibrium will be limited to the number of simultaneously limiting resources, generally three or fewer. However, natural phyto‐plankton assemblages usually exhibit high species diversity, hence the concept of Hutchinson's “paradox of the plankton”. Recent works have suggested that this apparent paradox is a result of disturbances inte...

Temporal changes in the abundance of Peridinium gatunense Nygaard in the water column of warm monomictic Lake Kinneret were followed during 1990–1994. Sedimentation rates of this dinoflagellate were followed concurrently by means of sediment traps with and without a preservative (Formalin), positioned at the base of the epilimnion and within the hypolimnion, for exposure periods of 2–3 weeks. Upper trap catches of total P. gat...