The feeding impact of planktivorous fish on microbial organisms is still poorly understood. We followed the seasonal dynamics of the food web in two natural fishponds for two years: one was stocked with planktivorous whitefish while the other had no planktivorous fish. The aim of the study was the simultaneous assessment of the feeding behaviours of planktivorous fish and of bacterivorous meta-/protozooplankters. We hypothesized that in the presence of planktivorous fish there would be fewer metazooplankton, more protozoans and decreased numbers of bacteria. Our results showed that the amount of metazooplankton eaten by the fish was indeed negatively correlated with metazooplankton biomass. The feeding impact of planktivorous fish in shaping the microbial loop was remarkable. The main grazers of bacteria in the fishpond were ciliates, whereas in the pond without fish these were heterotrophic nanoflagellates. In the fishless pond the role of the top predator shifted to the predaceous metazooplankter Leptodora kindtii which controlled the abundance of herbivorous metazooplankters. We found a negative relationship between the number of bacteria and flagellates in the fishless pond, while the number of bacterivorous ciliates was suppressed by predaceous ciliates. Therefore the bacteria-grazing activity was higher in the absence of planktivorous fish.
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http://dx.doi.org/10.1016/j.ejop.2014.01.006 | DOI Listing |
Sci Total Environ
February 2025
Coastal and Ocean Management Institute, Xiamen University, Xiamen 361102, China; Department of marine biology, Xiamen Ocean vocational college, Xiamen 361102, China; College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang 524088, China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, China; College of Ocean and Earth Science, Xiamen University, Xiamen 361102, China. Electronic address:
This research on microplastics (MPs) in marine environments, particularly in Bay of Bengal fish, underscores the limited comprehension of their accumulation and potential health and environmental consequences. The study investigated the abundance of MPs in the organs of nine marine fish species from the north Bay of Bengal, assessing their polymeric risks and implications for human health. The average MPs ingested by each individual was 32.
View Article and Find Full Text PDFFish Physiol Biochem
January 2025
Institute of Agrifood Research and Technology (IRTA), Centre de La Ràpita, Crta. Poble Nou del Delta Km 5.5, 43540, la Ràpita, Spain.
The effect of different feeding habits on gut morphology and digestive function has been intensively studied during the last decades but sympatric closely related fishes are relatively rare objects of such studies. In the present study, we have identified both morphological and physiological changes in the digestive system of a sympatric pair of whitefish represented by "normal" Coregonus lavaretus pidschian (benthivorous) and "dwarf" C. l.
View Article and Find Full Text PDFPLoS One
January 2025
College of Natural and Computational Sciences, Hawai'i Pacific University, Honolulu, HI, United States of America.
Climate change is imposing multiple stressors on marine life, leading to a restructuring of ecological communities as species exhibit differential sensitivities to these stressors. With the ocean warming and wind patterns shifting, processes that drive thermal variations in coastal regions, such as marine heatwaves and upwelling events, can change in frequency, timing, duration, and severity. These changes in environmental parameters can physiologically impact organisms residing in these habitats.
View Article and Find Full Text PDFJ Environ Manage
January 2025
School of Environment, State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing, 100875, China.
Water diversions can mitigate water scarcities by strategically reallocating water resources. Despite their benefits, these interventions may profoundly affect biodiversity and multiple ecological functions ("multifunctionality") within highly managed lake systems. However, the specific impact of such interventions on the relationship between biodiversity and multifunctionality remains elusive, which limits our grasp of how water regulation shapes the dynamics of managed lake ecosystems.
View Article and Find Full Text PDFGlob Chang Biol
December 2024
School of Biological Sciences, University of Bristol, Bristol, UK.
Artificial light at night (ALAN) is an anthropogenic pollutant that is intensifying and expanding in marine environments, but experimental studies of community-level effects are generally lacking. The inshore, shallow, and clear-water locations of coral reefs and their diverse photosensitive inhabitants make these ecosystems highly susceptible to biological disturbances; at the same time, their biodiversity and accessibility make them model systems for wider insight. Here, we experimentally manipulated ALAN using underwater LED lights on a Polynesian reef system to investigate the influence on localised nighttime fish communities compared to control sites without ALAN.
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