Underestimated methane production triggered by phytoplankton succession in river-reservoir systems: Evidence from a microcosm study

Algal Organic Matter Drives Methanogen-Mediated Methylmercury Production in Water from Eutrophic Shallow Lakes

“…, under AOM input), Archaea may occupy a far wider range of environmental niches than bacteria and exhibit better responsiveness, competitiveness, and utilization efficiency for bioavailable carbon sources, leading to their key role in promoting microbial MeHg production. Recent studies showed that eutrophication could result in active methanogenesis, indicating that the enhanced abundance/activities of methanogens could be stimulated by carbon input associated with algal decomposition. , Similar to our observations, methanogens on periphyton in lake water have also been reported to act as major contributors to MeHg formation, possibly due to their better adaptation to the highly competitive environment created by periphytic biofilm in lakes …”

“…Recent studies showed that eutrophication could result in active methanogenesis, indicating that the enhanced abundance/activities of methanogens could be stimulated by carbon input associated with algal decomposition. 69,70 Similar to our observations, methanogens on periphyton in lake water have also been reported to act as major contributors to MeHg formation, possibly due to their better adaptation to the highly competitive environment created by periphytic biofilm in lakes. 47 However, under oligotrophic conditions, the contributions of other microbial methylators (e.g., SRB or FeRB) to Hg methylation cannot be ignored.…”

“…In addition to Hg, the input of AOM has also been found to increase in arsenate reductase genes ( arr A and ars C) and thus promote As­(V) reduction to As­(III) . Similarly, the decomposition of lake-dominated algae (Chlorella pyrenoidosa and Microcystis aeruginosa) provided abundant labile organic matter, which jointly elevated mcrA and the mcrA / pmoA ratio, enhancing CH 4 production . More microbial researches, for example, by investigating short- and long-term microbial responses to various fractions of AOM as well as exploring their subsequent effects on element cycling, are needed in future studies.…”

Century-Long Homogenization of Algal Communities Is Accelerated by Nutrient Enrichment and Climate Warming in Lakes and Reservoirs of the North Temperate Zone

“…EA and CYA communities in reservoirs also exhibited homogenization after the 1980s (Figure ). In addition to nutrient enrichment and climatic warming, the hydrological regime controlled by dams undoubtedly represents a major driver of aquatic ecosystem dynamics in reservoirs by influencing photosynthetic active radiation and nutrient variation within the water column. ,, Dam construction leading to increased water residence time, improved light penetration, nutrient retention, and sediment trapping in an impounded reservoir has been suggested to promote phytoplankton biomass production while also promoting the succession of dominant phytoplankton from river-dominant to lake-dominant taxa. − Many studies have documented the homogenization of river flow regimes resulting from the fragmentation of river corridors by dams and the associated modification of fluvial processes and streamflow dynamics that pose significant threats to global freshwater biodiversity. − The results shown here provide evidence for temporal homogenization of phytoplankton communities in reservoirs, although direct evidence is not available to quantify the influence of damming.…”

Synergetic Effect of Ni2P and MXene Enhances Catalytic Activity in the Hydrogen Evolution Reaction

“…Environmental pollution and ever-growing energy shortage have attracted broad interest to exploit clean and sustainable energies. − H 2 , the most efficient and environment-friendly fuel, is deemed a potential candidate for replacing traditional energies . In order to produce high-quality hydrogen, a highly attractive approach is the electrocatalytic hydrogen evolution reaction (HER) .…”