Artigos de revistas: "Freshwater zooplankton"

1

Havens, Karl E. "Zooplankton dynamics in a freshwater estuary". Archiv für Hydrobiologie 123, n.º 1 (15 de novembro de 1991): 69–97. http://dx.doi.org/10.1127/archiv-hydrobiol/123/1991/69.

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Pathak, S. K., e Sandhya Kshetrey. "Seasonal trends in physico-chemical parameters and zooplankton in a freshwater reservoir of Dejla Dewada, Khargone, M.P." Environment Conservation Journal 15, n.º 1&2 (18 de junho de 2014): 225–28. http://dx.doi.org/10.36953/ecj.2014.151232.

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Seasonal variation in physico-chemical and zooplankton communities of Dejla Dewada Reservoir (D.D.R.), West Nimar district (Khargone) was studied during October 2009 to September 2010. Protozoa, Rotifera, Copepoda, Cladocera and Ostrcoda were found dominated zooplanktonic groups. The total zooplankton density ranged between 879 unit/L to 2980 unit/L.The composition of zooplankton was found as Protozoa >Rotifera>Copepoda>Cladocera>Ostracoda.

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Morton, K. F., e S. G. MacLellan. "Acoustics and freshwater zooplankton". Journal of Plankton Research 14, n.º 8 (1992): 1117–25. http://dx.doi.org/10.1093/plankt/14.8.1117.

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AKHTAR, NAVEED, SARA HAYEE, FAHEEM NAWAZ, AMIR NADEEM, ABDUL QAYYUM KHAN SULEHRIA e FARAH ASHFAQ. "IMPACTS OF PHYSICOCHEMICAL PARAMETERS ON ZOOPLANKTON BIODIVERSITY RECORDED FROM SAFARI ZOO LAKE LAHORE, PUNJAB, PAKISTAN". Pakistan Journal of Emerging Science and Technologies (PJEST) 3, n.º 2 (2023): 1–12. http://dx.doi.org/10.58619/pjest.v3i2.75.

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Zooplanktons are an integral part of any water reservoir, whether freshwater or marine. They are linked in food chains and the food web of a water ecosystem. Some zooplanktons are food for other zooplankton types. The diversity and density of these creatures are affected by eutrophication and changes in Physico-chemical parameters. Some species of zooplanktons are found in eutrophic water bodies. They are important bio-indicators, and their presence reflects the eutrophic condition of any water body. These organisms have a worldwide distribution, playing a pivotal role in shaping the whole community structure of any water reservoir and unfolding the close connections of various trophic levels. The present study explores the density and diversity of various types of zooplankton found in Safari Zoo Lake, Lahore. The study on an artificial lake with lesser water replacement pictured different zooplankton groups, including copepod, tintinnids, cladoceran and rotifers with many larger animals, which affected the overall zooplankton population. Since Physico-chemical parameters also affect the density and diversity of zooplankton, water samples were collected to measure various parameters every month. A very low density and diversity of zooplanktons were recorded during this study, where rotifers were the most abundant. The lake condition showed eutrophication getting support from bio-indicator species like Brachionus calyciflorus.

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Hitchcock, James N., Simon M. Mitrovic, Wade L. Hadwen, Ivor O. Growns e Ann-Marie Rohlfs. "Zooplankton responses to freshwater inflows and organic-matter pulses in a wave-dominated estuary". Marine and Freshwater Research 67, n.º 9 (2016): 1374. http://dx.doi.org/10.1071/mf15297.

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Freshwater inflow events play a major role in structuring estuarine zooplankton communities. Freshwater inflow events affect zooplankton directly through advective forcing and changes in salinity, and indirectly through changes to resources by the delivery of organic carbon and nutrients that can stimulate microbial and primary production. Here, we investigate changes to estuarine zooplankton assemblage structure, density and δ13C stable isotopes during a period of highly variable freshwater inflow in the Bega River estuary, Australia. High inflows resulted in a reduction of salinity and a shift in the zooplankton assemblage structure from purely estuarine taxa towards freshwater taxa. The density of select genera of rotifers, cladocera and, in the upper estuary, copepods, increased following inflows, concurrent with increases in the concentration of dissolved organic carbon and bacterial biomass. Redundancy analysis found that environmental variables including discharge, dissolved organic carbon, salinity and bacterial biomass explained 66–73% of zooplankton variation. Stable isotope results indicated that all copepod and cladocera species tested were predominantly supported by allochthonous carbon from terrestrial sources. The present results have provided important evidence that freshwater inflows play a critical role in structuring zooplankton assemblages and supporting increased production through the delivery of allochthonous organic carbon.

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Guermazi, Wassim, Mohammad El-khateeb, Muna Abu-Dalo, Ikbel Sallemi, Bashar Al-Rahahleh, Amira Rekik, Genuario Belmonte, Habib Ayadi e Neila Annabi-Trabelsi. "Assessment of the Zooplankton Community and Water Quality in an Artificial Freshwater Lake from a Semi-Arid Area (Irbid, Jordan)". Water 15, n.º 15 (2 de agosto de 2023): 2796. http://dx.doi.org/10.3390/w15152796.

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Zooplankton play a crucial role in aquatic food chains and contain many species, which could be bioindicators of water quality and ecosystem health. The ecological impacts of eutrophication on zooplankton composition in freshwater lakes have recently gained wide interest. Geographic location and water-body size influence zooplankton diversity in freshwaters; meanwhile, less is known about the composition and dynamic of the zooplankton community and their relationship with the trophic status in artificial water in semi-arid areas. The present study aimed to assess the physical–chemical parameters and to document the seasonal distribution of zooplankton species and their relationship with environmental factors and trophic state in the artificial freshwater lake JUST, in a semi-arid area. The high concentrations of nutrients and the trophic level index (TLI) classified the lake as eutrophic–hypertrophic. The zooplankton in the JUST lake were composed of twenty-six species, with eleven Rotifera, ten Copepoda, and five Cladocera. Copepoda was numerically the most abundant taxon, accounting for 64% of the total zooplankton abundance, in both seasons. However, the second most abundant taxon in summer was Rotifera (28.26%) while in winter it was Cladocera (25.88%). The community structure seemed to be influenced, most likely, by trophic state, phytoplankton abundance, water temperature, dissolved oxygen, and nutrient loading. The zooplankton were largely dominated by bioindicator species of high trophic levels. Zooplankton could be used as a tool to monitor the trophic state of the lake. For sustainable development, the introduction of phytoplanktivorous, aquaculture species, such as carp and koi, will strengthen the top-down control of the phytoplankton concentration, leading to a reduced trophic state.

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McQueen, Donald J., John R. Post e Edward L. Mills. "Trophic Relationships in Freshwater Pelagic Ecosystems". Canadian Journal of Fisheries and Aquatic Sciences 43, n.º 8 (1 de agosto de 1986): 1571–81. http://dx.doi.org/10.1139/f86-195.

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Relative impacts of bottom-up (producer controlled) and top-down (consumer controlled) forces on the biomass and size structure of five major components of freshwater pelagic systems (piscivores, planktivores, zooplankton, phytoplankton, and total phosphorus availability) were estimated. Predictions that emerge are (1) maximum biomass at each trophic level is controlled from below (bottom-up) by nutrient availability, (2) this bottom-up regulation is strongest at the bottom of the food web (i.e. phosphorus → phytoplankton) and weakens by a factor of 2 with each succeeding step up the food web, (3) as energy moves up a food web, the predictability of bottom-up interactions decreases, (4) near the top of the food web, top-down (predator mediated) interactions are strong and have low coefficients of variation, but weaken with every step down the food web, (5) variability around the bottom-up regressions can always be explained by top-down forces, and (6) interplay between top-down and bottom-up effects changes with the trophic status of lakes. In eutrophic lakes, top-down effects are strong for piscivore → zooplankton, weaker for planktivore → zooplankton, and have little impact for zooplankton → phytoplankton. For oligotrophic lakes, the model predicts that top-down effects are not strongly buffered, so that zooplankton → phytoplankton interactions are significant.

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Kar, Sulata, Papia Das, Uma Das, Maibam Bimola, Devashish Kar e Gautam Aditya. "Correspondence of zooplankton assemblage and water quality in wetlands of Cachar, Assam, India: Implications for environmental management". Limnological Review 18, n.º 1 (1 de março de 2018): 9–19. http://dx.doi.org/10.2478/limre-2018-0002.

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AbstractThe zooplankton assemblage of selected wetlands of Assam, India was assessed to deduce the structural variation in the context of water quality parameters. A two year study between 2012 and 2014 comprising of 530 samples from the five wetlands revealed the presence of 46 taxa, 26 Rotifera, 15 Cladocera, 4 Copepoda and 1 Ostracoda, in varying density. The rotifers dominated in terms of abundance (48 ind. cm−3) followed by the cladocerans (28 ind. cm−3) and the copepods (19 ind. cm−3) and showed significant (p <0.05) correlations with turbidity, alkalinity, hardness and phosphate contents of the water samples. The diversity and the richness of the zooplankton showed an increasing trend with the water temperature. Among the different taxa, Brachionus sp. was most abundant followed by Mesocyclops sp. while Beauchampiella sp. was represented in the least numbers. Application of the cluster analysis allowed the segregation of the different zooplankton based on the similarities of abundance in the samples. The water quality parameters like temperature, alkalinity, turbidity, magnesium and calcium were observed to be significant contributors in shaping the zooplankton community composition of the wetlands, revealed through the correlations and canonical correspondence analysis. As an extension, the information can be used in monitoring the quality of the freshwater habitats of the concerned and similar geographical regions, using the zooplankton as the major constituents. The variations in the abundance of cladoceran, copepod and rotifer zooplanktons can be used to understand the mechanisms that sustain the food webs of the aquatic community of the freshwater bodies.

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Sudha Bansode e Pankaj Pawar. "Study of freshwater zooplanktons in Nira River around Akluj". International Journal of Multidisciplinary Research Updates 7, n.º 2 (30 de maio de 2024): 055–60. http://dx.doi.org/10.53430/ijmru.2024.7.2.0033.

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Present investigation has been conducted on Nira river around Akluj with special reference to its zooplankton diversity in relation physico-chemical characteristics. 105 (One hundred and five) zooplankton species were identified from Nira river Akluj which consisted of Rotifera 43 species (41%), Cladocera 25 species (24%), Protozoa 20 species (19%), Copepoda 12 species (11%) and Ostracoda 5 species (5%). The investigation on physico-chemical characteristics at different sites revealed its alkaline nature, suitable for aquaculture practices. Significant site variations have been recorded due to the interference of sewage and agricultural wastes. Among all the zooplankton groups, Rotifera recorded dominance. Maximum diversity of zooplankton population was recorded at macrophytic sites during summer season.

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Grossart, Hans-Peter, Claudia Dziallas e Kam W. Tang. "Bacterial diversity associated with freshwater zooplankton". Environmental Microbiology Reports 1, n.º 1 (fevereiro de 2009): 50–55. http://dx.doi.org/10.1111/j.1758-2229.2008.00003.x.

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Coke, Mike. "A Guide to Tropical Freshwater Zooplankton". African Journal of Aquatic Science 28, n.º 1 (janeiro de 2003): 87–88. http://dx.doi.org/10.2989/16085914.2003.9626605.

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Pilati, Alberto, Wayne A. Wurtsbaugh e Nathaniel R. Brindza. "Evidence of coprophagy in freshwater zooplankton". Freshwater Biology 49, n.º 7 (julho de 2004): 913–18. http://dx.doi.org/10.1111/j.1365-2427.2004.01234.x.

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BARI, JABER BIN ABDUL, MD SAIFUL ISLAM, SANJIDA AKTER NISA, NAZNIN AKTER TISHA, IRINA MASHKOVA e NAJMUS SAKIB KHAN. "Responses of Freshwater Zooplankton as Biological Indicators to the Aquatic Chemical Properties". Current Environment 1, n.º 01 (24 de outubro de 2021): 9–14. http://dx.doi.org/10.54479/ce.v1i01.6659.

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Zooplankton are found very sensitive to even slight aquatic pollution due to a number of chemical imbalances in freshwater bodies. As an amazing tiny creature zooplankton play a very crucial role in the aquatic food chain by transferring energy from primary levels to tertiary organisms. For many years it has been well established that zooplankton act as promising biological indicators to continuously fluctuating aquatic environments and subsequently to global warming. While reacting to these aquatic environmental fluctu-ations, zooplankton population growth can either be stimulated or inhibited. The presence or absence of particular zooplankton species can reveal the trophic status of the water body. Moreover, in a harsh env-ironment, algal toxins may have drastic effects on the behavioral characteristics of zooplankton.

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Karpowicz, Maciej, Jolanta Ejsmont-Karabin, Joanna Kozłowska, Irina Feniova e Andrew R. Dzialowski. "Zooplankton Community Responses to Oxygen Stress". Water 12, n.º 3 (5 de março de 2020): 706. http://dx.doi.org/10.3390/w12030706.

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Recent changes in climate and eutrophication have caused increases in oxygen depletion in both freshwater and marine ecosystems. However, the impact of oxygen stress on zooplankton, which is the major trophic link between primary producers and fish, remains largely unknown in lakes. Therefore, we studied 41 lakes with different trophic and oxygen conditions to assess the role of oxygen stress on zooplankton communities and carbon transfer between phytoplankton and zooplankton. Samples were collected from each lake at the peak of summer stratification from three depth layers (the epilimnion, metalimnion, and hypolimnion). Our results revealed that freshwater zooplankton were relatively tolerant to anoxic conditions and the greatest changes in community structure were found in lakes with the highest oxygen deficits. This caused a switch in dominance from large to small species and reduced the zooplankton biomass in lower, anoxic layers of water, but not in the upper layers of water where the oxygen deficits began. This upper anoxic layer could thus be a very important refuge for zooplankton to avoid predation during the day. However, the reduction of zooplankton in the lower water layers was the main factor that reduced the effectiveness of carbon transfer between the phytoplankton and zooplankton.

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Freyre, LR, DC Colautti, ME Maroñas, ED Sendra e M. Remes-Lenicov. "Seasonal changes in the somatic indices of the freshwater silverside, Odontesthes bonariensis (Teleostei, Atheriniformes) from a Neotropical shallow lake (Argentina)". Brazilian Journal of Biology 69, n.º 2 (maio de 2009): 389–95. http://dx.doi.org/10.1590/s1519-69842009000200023.

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The study object was an Odontesthes bonariensis (Valenciennes, 1835) population of a characteristically shallow lake from the pampasic region. Over one year, zooplankton and fish samples were collected monthly. As a function of time and gender, several indices were investigated (relative weight, mesentery fat index, gonadosomatic index, hepatosomatic index and somatic index) and were related to zooplanktonic community dynamics, the main energy food source for this species. The results indicate that the seasonal information contained in the weight compartments is most important in mesentery fat, gonads and liver. The zooplankton availability modulates reserves (fat) behaviour and physiologic activity (liver), determining spawn intensity. Thus, in spring spawns, with higher zooplankton availability, mature individuals of the population, males and females, transfer energy from the food to the gonads. In autumn spawns, they use the fat reserves for gonad ripening.

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Wang, Qianhong, Zheng Hao, Ruirui Ding, Huabing Li, Xiangming Tang e Feizhou Chen. "Host Dependence of Zooplankton-Associated Microbes and Their Ecological Implications in Freshwater Lakes". Water 13, n.º 21 (20 de outubro de 2021): 2949. http://dx.doi.org/10.3390/w13212949.

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Zooplankton is colonized by quite different microbes compared with free-living and particle-associated bacteria, serving as a non-negligible niche of bacteria in aquatic ecosystems. Yet detailed analysis of these bacterial groups is still less known, especially in freshwater lakes. To widen our knowledge of host-microbe interaction and bacterial ecosystem functions, we chose two specific populations of zooplankton, i.e., cladoceran Moina and copepod Calanoids, as hosts from five natural lakes, and illustrated detailed features of their associated bacteria. Through 16S rRNA gene sequencing, we found microbes colonized on Calanoids presented significantly higher α-diversity, stronger bacterial interaction and metabolic function potentials than for Moina. It was also notable that zooplankton-associated bacteria showed a high potential of fatty acid metabolism, which is beneficial for host’s development. Moreover, we found that zooplankton-associated microbes may exert profound effects on biogeochemical cycles in freshwater lakes, since several bacterial members able to participate in carbon and nitrogen cycles were found abundant. Overall, our study expands current understanding of the host-microbe interaction and underlying ecological dynamics in freshwater ecosystem.

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Mishra, Anand, Sanjive Shukla, A. K. Chopra, Sandeep Shukla e Harnam Singh Lodhi. "A report on freshwater tailless flea, Simocephalus vetulus from Haridwar, located in foothills of Shivalik Himalaya in Uttarakhand, India". Journal of Applied and Natural Science 12, n.º 3 (12 de setembro de 2020): 438–41. http://dx.doi.org/10.31018/jans.v12i3.2351.

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The Cladocerans, commonly known as “Water fleas” form a primitive freshwater group of micro crustacean zooplankton of the freshwater ecosystem. They play an important role in the aquatic food chain and also contribute significantly to zooplankton dynamics and secondary productivity in freshwater ecosystems. The animals used in the present study were identified as Simocephalus vetulus with the help of identification keys described by various authors in the previous studies from other parts of India. In the present study, the occurrence of “freshwater tailless flea”, S. vetulus (Crustacea- cladocera) is reported for the first time from freshwater bodies in Haridwar, located in foothills of Shivalik Himalayan region in Uttarakhand. The presence of S. vetulus “tailless water flea” will be helpful as a lab model for the health status of aquatic bodies as well as environmental monitoring.

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Zade, S. B., Shashikant R. Sitre e Rajendra V. Tijare. "Occurrence of zooplankton in a perennial freshwater reservoir of Wadgaon Dam during monsoon season at Nagpur District". Environment Conservation Journal 10, n.º 1&2 (16 de junho de 2009): 81–83. http://dx.doi.org/10.36953/ecj.2009.101213.

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The zooplankton occupy a central position between the autotrophs and heterotrophs and form an important link in the food chain of a freshwater ecosystem. The occurrence and abundance of zo0plankton is always influenced by physico-chemical factors and the level of nutrients present in the water body. In this context a perennial freshwater reservoir Wadgaon dam is studied with respect to zooplankton population to assess the types of zooplankton present. Qualitative studies on the zooplankton in the Wadgaon dam reservoir situated in the Nagpur district were undertaken in monsoon months to assess the extent of forms present. The reservoir water is uncontaminated and clean with no influence of man made activities in the vicinity. The zooplankton population of the reservoir water is found to be represented by fie different groups viz. Protozoa, Rotifera, Cladocera, Copepoda and Ostracoda represented by about 21 different forms. The present study indicate the uncontaminated nature of reservoir water due to absence of pollution indicator species in the reservoir water.

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Cervantes-Martínez, Adrián, Carlos Alberto Durán Ramírez, Manuel Elías-Gutiérrez, Alma E. García-Morales, Martha Gutiérrez-Aguirre, Sarahi Jaime, Miroslav Macek et al. "Freshwater Diversity of Zooplankton from Mexico: Historical Review of Some of the Main Groups". Water 15, n.º 5 (23 de fevereiro de 2023): 858. http://dx.doi.org/10.3390/w15050858.

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In this review, we include rotifers, copepods, and cladocerans, including other groups not usually deemed as zooplankters: i.e., protists, acari, and large branchiopods. The objectives of this study were to integrate the dispersed literature on the taxonomy and diversity of these freshwater zooplankton groups and to explain (1) how these contributions can be arranged in distinct historical periods and (2) how this knowledge has allowed the detection of exotic and threatened species. We divided the freshwater zooplankton studies in Mexico into three historical periods: the first one comprised the 1840s to the 1940s when foreign researchers carried out most studies during several expeditions. Spanish researchers promoted surveys on different zooplankton taxa at the end of this first period. The second period, from the early 1950s to the end of the 1990s of the XX century, showed a remarkably increased research activity in its last ten years only (that is, during the 1990s to 2000), represented by contributions of a new generation of Mexican zooplanktologists. This period yielded more complete zooplankton listings and detailed morphological descriptions of rotifers, cladocerans, copepods, and large branchiopods. The third period started from the year 2000 to date. During this time, listings and online faunistic baselines based on integrative taxonomy have been the primary trend. An account of exotic zooplankters and conservation issues of several native species are discussed. The results of this review show that the knowledge of the freshwater zooplankton of this country has increased significantly over the last 40 years, with at least 408 first records of species for Mexico. Currently, the knowledge of Mexican freshwater zooplankton is among the most complete in the world. However, it is estimated that only a small fraction of the true diversity has been documented.

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Pulsifer, Jennifer, e Edward Laws. "Temperature Dependence of Freshwater Phytoplankton Growth Rates and Zooplankton Grazing Rates". Water 13, n.º 11 (4 de junho de 2021): 1591. http://dx.doi.org/10.3390/w13111591.

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Phytoplankton growth rates and zooplankton grazing rates were estimated on 16 occasions over a period of 17 months in University Lake, a highly eutrophic lake on the campus of Louisiana State University. Phytoplankton growth rates and chlorophyll a concentrations averaged 1.0 ± 0.2 d−1 and 240 ± 120 mg m−3, respectively. Chlorophyll a concentrations were at or above the inflection point of the Holling type I curve that described the relationship between zooplankton grazing rates and chlorophyll a concentrations. In most cases, it was necessary to dilute lake water by more than a factor of 4 before zooplankton grazing rates became sensitive to chlorophyll a concentrations. Chlorophyll a concentrations were positively correlated with temperature and were roughly fourfold higher at 30 °C than at 15 °C. An analysis of the temperature dependence of the growth rates and grazing rates in this study and 87 other paired estimates of limnetic phytoplankton growth rates and zooplankton grazing rates revealed virtually identical temperature dependences of growth rates and grazing rates that were very similar to the temperature dependence predicted by the metabolic theory of ecology. Phytoplankton growth rates exceeded zooplankton grazing rates by 0.13 ± 0.05 d−1 at all temperatures over a temperature range of 8.5–31.5 °C. The Q10 for both phytoplankton growth rates and zooplankton grazing rates was 1.5 over that temperature range.

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Stockwell, J. D., e O. E. Johannsson. "Temperature-dependent allometric models to estimate zooplankton production in temperate freshwater lakes". Canadian Journal of Fisheries and Aquatic Sciences 54, n.º 10 (1 de outubro de 1997): 2350–60. http://dx.doi.org/10.1139/f97-141.

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Empirical relationships between body size and temperature, and daily P/B of temperate freshwater zooplankton species were derived from the literature. Body size explained 81% of the variation in daily P/B of zooplankton at temperatures <<= 10°C and 48% at temperatures >10°C. The two relationships did not differ in slope but significantly differed in elevation. The regression models were then applied to zooplankton samples collected from a midlake station in Lake Ontario to predict zooplankton seasonal production. Production estimates from the regression models, when compared with estimates from the egg ratio method for the same data set, were similar for cladoceran species, four and 10 times higher for two copepod species, and two times higher for total zooplankton production. In general, these differences are within the range expected based on previous studies that compared different production models. The regression models can provide quick, independent estimates of zooplankton production to complement estimates based on traditional, species-specific methods. Furthermore, the models can be used in conjunction with automated synoptic instruments, such as optical plankton counters and temperature probes, to provide production estimates that better represent large, complex systems such as the Great Lakes.

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Huang, Chih-Hsiung, Tah-Wei Chu, Chiu-Hui Kuo, Ming-Chang Hong, Yu-Yun Chen e Bonien Chen. "Effects of Microplastics on Reproduction and Growth of Freshwater Live Feeds Daphnia magna". Fishes 7, n.º 4 (22 de julho de 2022): 181. http://dx.doi.org/10.3390/fishes7040181.

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In recent years, much research has focused on studying the damage caused by microplastics to the ecological environment and human health. Indeed, MPs are often consumed by shellfishes and zooplanktons due to their similarity in size to POM (particular organic matter). Especially in zooplankton, the accumulation of MPs in the body affects the reproductive system and the growth rate of juveniles. Moreover, toxins derived from MPs are continuously accumulated in predators of zooplankton and impact the whole ecosystem across the food chain. In this work, we found that even though MPs were internalized by and adherent around Daphnia magna, there were no significant differences in the survival rate of their adults and offspring. However, the population of ovigerous adults under high MPs exposure for 7 days decreased significantly, suggesting an extension of the days of sexual maturity in D. magna. The removal of MPs after 7 days’ MPs treatment resulted in an increase in D. magna juveniles and neonates which indicated their growth was reduced or inhibited in the MPs environment. Overall, the uptake of MPs led to negative effects on population reproduction and the growth of offspring in D. magna.

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Mort, Mona A. "Ecological genetics of freshwater zooplankton: Current research and future perspectives". Archiv für Hydrobiologie 123, n.º 2 (6 de dezembro de 1991): 129–41. http://dx.doi.org/10.1127/archiv-hydrobiol/123/1991/129.

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Balkić, Anita Galir, Tanja Žuna Pfeiffer, Karla Čmelar, Dubravka Špoljarić Maronić, Filip Stević, Nikolina Bek, Ana Martinović e Rahela Nikolašević. "Footprint of the plastisphere on freshwater zooplankton". Environmental Research 212 (setembro de 2022): 113563. http://dx.doi.org/10.1016/j.envres.2022.113563.

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Campbell, C. E., e E. E. Prepas. "Evaluation of Factors Related to the Unusually Low Chlorophyll Levels in Prairie Saline Lakes". Canadian Journal of Fisheries and Aquatic Sciences 43, n.º 4 (1 de abril de 1986): 846–54. http://dx.doi.org/10.1139/f86-104.

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Prairie saline lakes in Canada have remarkably low chlorophyll a (Chl a) levels relative to total phosphorus (TP) and total nitrogen (TN) levels. To evaluate factors related to low Chl a levels, three Alberta saline lakes (total dissolved solids > 5 g∙L−1) were studied in 1983 and 1984. Mean summer phytoplankton Chl a ranged from 3 to 10 μg∙L−1, mean summer periphyton Chl a was less than 70 mg∙m−2, while mean summer TP and TN ranged from 2 to 13 and from 4 to 11 mg∙L−1, respectively. Chl a and phytoplankton primary production were extremely low relative to predictions from measured TP and TN levels and empirical models for freshwaters. Bioassays indicated that inorganic phosphorus was not limiting, whereas inorganic nitrogen was limiting algal growth. Bacterial densities and zooplankton dry weight were high (> 107 cells∙mL−1 and > 1.0 mg∙L−1, respectively) relative to predictions from Chl a and empirical models for freshwaters. Phytoplankton biomass was insufficient to maintain the zooplankton populations; bacteria and detritus were likely a major food source for zooplankton. This study suggests that freshwater models are not applicable to prairie saline lakes.

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Imoobe, T. O. T., e M. L. Adeyinka. "Zooplankton-based assessment of the trophic state of a tropical forest river in Nigeria". Archives of Biological Sciences 61, n.º 4 (2009): 733–40. http://dx.doi.org/10.2298/abs0904733i.

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In this study, we explore the usefulness of zooplankton as a tool for assessing the trophic status of a Nigerian forest river. The river was sampled monthly and investigated for water physico-chemistry and zooplankton community structure using basic statistical measurement of diversity indices to characterize the zooplankton fauna. The trophic sta?tus of the river evaluated from its physico-chemical parameters indicates that the river is oligotrophic. The zooplankton composition was typical of a tropical freshwater river, with a total of 40 species, made up of 16 rotifers, 12 cladocerans, and 12 copepods and their developing stages in the following order of dominance: Rotifera > Cladocera > Cyclopoida > Calanoida. There were strong correlations between the lake's trophic status and its zooplankton communities. The zoo?plankton community was dominated by numerous species of rotifers and crustaceans, which are typical of oligotrophic to mesotrophic systems, such species including Conochilus dossuarius and Synchaeta longipes. However, the most dominant zooplankton species in West African freshwater ecosystems, viz., Keratella tropica, Keratella quadrata, Brachionus angularis, Trichocerca pusilla, Filinia longiseta, Pompholyx sulcata, and Proales sp., and others that are indicator species of high trophic levels, were not recorded in the river. The river is very clear and can be used for all manner of recreational activities.

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Chen, Tao, Liyan Yin, Wei Li, Jiaquan Huang, Xiaohang Zhang e Yu Cao. "Do Submerged Macrophytes Influence the Response of Zooplankton and Benthic Ostracoda to NaCl Salinity Gradients in Shallow Tropical Lakes?" Water 16, n.º 11 (27 de maio de 2024): 1542. http://dx.doi.org/10.3390/w16111542.

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Both the increasing salinity levels and the decline of submerged macrophytes represent growing concerns in global freshwater ecosystems, posing a threat to water quality and various aquatic organisms. However, there is a limited understanding of the interactive effects of salinity and submerged macrophytes on zooplankton and benthic Ostracoda in tropical zones. To address this knowledge gap, we conducted a controlled experiment spanning 6 months, comparing the biomass of zooplankton (including copepods, cladocerans, and rotifers) and benthic Ostracoda in mesocosms with three levels of salinity, at the presence or absence of submerged macrophytes. Our results showed that in tropical zones, both zooplankton and benthic Ostracoda biomass exhibited a noteworthy decrease in response to increasing salinity, but the presence of submerged macrophytes did not have a significant influence on the zooplankton biomass. However, the presence of submerged macrophytes had a positive effect on the benthic Ostracoda biomass. Interestingly, submerged macrophytes had a strong interaction with salinity on the Ostracoda biomass, which increased with macrophyte presence under intermediate salinity conditions (2 g/L). In summary, our study sheds light on the interplay between salinity, submerged macrophytes, and the biomass of zooplankton and benthic Ostracoda in tropical freshwater ecosystems.

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Norambuena, Juan-Alejandro, Patricia Poblete-Grant, Jorge F. Beltrán, Patricio De Los Ríos-Escalante e Jorge G. Farías. "Evidence of the Anthropic Impact on a Crustacean Zooplankton Community in Two North Patagonian Lakes". Sustainability 14, n.º 10 (17 de maio de 2022): 6052. http://dx.doi.org/10.3390/su14106052.

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Lately, agriculture, livestock, forestry, and aquaculture activities have been greatly developed in Chilean North Patagonia, negatively impacting the balance of the environmental conditions in lakes and affecting the development and survival of several native species. The aim of this study was to assess the anthropic impact on a zooplankton community in two North Patagonian lakes. We collected samples from four sites belonging to Lake Icalma and Lake Llanquihue, including four replicates per site. Water samples were analyzed for physicochemical characteristics and zooplankton communities. We focused on the presence of Daphnia pulex, a species of zooplanktonic crustacean that performs a key role in capturing energy from primary producers to deliver it to final consumers such as fish. We found that Llanquihue showed higher total phosphorus, nitrogen, copper, iron, manganese, total dissolved solids (TDS), and conductivity (EC) than Icalma. Furthermore, ecological variables were greatly decreased due to total P, total N, manganese, copper, total dissolved solids, and conductivity, which changed the species dominance of the zooplankton community in Llanquihue, indicating some degree of anthropization. This study provides fundamental information on the anthropogenic impact on water quality, as well as on zooplankton diversity, highlighting the importance of monitoring the health of these North Patagonia freshwater ecosystems.

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Gavrilko, D. E., G. V. Shurganova, I. A. Kudrin e B. N. Yakimov. "Identification of Freshwater Zooplankton Functional Groups Based on the Functional Traits of Species". Povolzhskiy Journal of Ecology, n.º 3 (19 de novembro de 2020): 290–306. http://dx.doi.org/10.35885/1684-7318-2020-3-290-306.

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Information on the functional traits of the most widespread species of freshwater zooplankton (Rotifera, Cladocera, and Copepoda) in European Russia was collected and analyzed. Our database includes 355 species described by 4 traits, namely: maximum body length, trophic group, feeding type, and movement type. Cluster analysis based on Gower's functional distances shows that freshwater zooplankton can be classified into 19 groups with different ecological roles. The characteristics of each identified functional group are presented. We believe it to be fundamentally important to build a unified classification using all available data and applicable characters for all three main taxonomic groups of zooplankton. Comparison with the existing ecological zooplankton classification proposed by Yu. S. Chuikov has demonstrated a number of advantages of our approach. Several ecological groups in Yu. S. Chuikov’s classification are represented by more fractional categories in our classification. Our system of functional groups can be used in studies of the structure of zooplanktocoenoses based on direct cluster analysis and ordination or based on functional distances between samples. To calculate the functional similarity between species, one can use our database of features, which is contained in the Appendix. Analysis based on functional groups gives a better unerstanding of the structure of a community than traditional ordination, which takes into account only the taxonomic affiliation of species. The approach used for functional group identification can be useful in assessing functional diversity and identifying patterns of freshwater zooplanktocoenoses dynamics. The database of functional signs of zooplankton can be used to check the relationship of functional signs with environmental factors.

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Jeziorski, Adam, e Norman D. Yan. "Species identity and aqueous calcium concentrations as determinants of calcium concentrations of freshwater crustacean zooplankton". Canadian Journal of Fisheries and Aquatic Sciences 63, n.º 5 (1 de maio de 2006): 1007–13. http://dx.doi.org/10.1139/f06-019.

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Calcium (Ca) is a major component of the crustacean zooplankton carapace. As crustacean zooplankton obtain most of their Ca from lake water, taxa with high Ca demands may be negatively affected if environmental Ca concentrations fall below thresholds necessary for adequate Ca uptake rates. Currently, Ca concentrations are falling in many soft-water lakes with a history of acid deposition, both within Canada and globally. Hence, there is a need to identify species with high Ca demands. We analyzed Ca concentrations of eight crustacean zooplankton taxa from nine lakes spanning a 0.435 mg·L1 Ca gradient. Our objectives were to determine (i) if both species identity and lake Ca concentrations are determinants of zooplankton Ca concentration and (ii) if zooplankton Ca concentration varies seasonally. Large differences in Ca concentrations were observed among taxa. Levels in Daphnia sp. ranged from 2% to 8% of dry body weight, whereas levels in copepods and non-daphniid cladocera were much lower at 0.2%0.4%. Seasonal variation in zooplankton Ca concentration was negligible, but positive correlations with lake Ca concentration were detected, with up to twofold differences in Ca concentration between lakes in three of the eight species. Species identity was the most important determinant of crustacean zooplankton Ca concentration.

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Ali, Sharique A. "On the Dominant Behavior of Zooplankton in Different types of Domestic Sewage Oxidation Ponds". Bioscience Biotechnology Research Communications 15, n.º 3 (30 de setembro de 2022): 475–79. http://dx.doi.org/10.21786/bbrc/15.3.15.

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Plankton are small microscopic organisms, comprising diatoms and algae, which form the basis of primary production, whereas zooplankton are mainly crustaceans, rotifers and larval stages of larger animals which constitute the higher aquatic food web. Both are bio-indicators of a water body, constituting the main food for the carnivorous and omnivorous fishes in the aquatic ecosystem. In the present work, a detailed analysis of zooplankton diversity along with variations in species, and seasonal abundance with average and total population density was carried out in different types of domestic sewage oxidation ponds. Similar analysis for a comparison was done in a freshwater control pond situated in Bhopal India. In this study out of 8 ponds, 4 were selected for zooplankton analysis two being primary and two being secondary sewage oxidation ponds and one freshwater control pond was selected for comparative analysis. The results indicated that the number of zooplankton in all ponds ranged from 162 to 14776 org/L, seasonally it was observed that the sewage oxidation ponds had the maximum population of zooplankton in winter, followed by rainy and summer seasons. Regarding the population of zooplankton in the individual oxidation ponds, it was found that sewage secondary pond IIIB had the maximum zooplankton followed by IIIA. Interesting observations on the cascading effects of physicochemical parameters on plankton dynamics, including the variations in the diel population of various species of zooplankton have been recorded. The phenomenon of plankton grazing in different types of domestic sewage ponds is being reported for the first time.

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Ali, Sharique A. "On the Dominant Behavior of Zooplankton in Different types of Domestic Sewage Oxidation Ponds". Bioscience Biotechnology Research Communications 15, n.º 4 (25 de dezembro de 2022): 531–35. http://dx.doi.org/10.21786/bbrc/15.4.9.

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Plankton are small microscopic organisms, comprising diatoms and algae, which form the basis of primary production, whereas zooplankton are mainly crustaceans, rotifers and larval stages of larger animals which constitute the higher aquatic food web. Both are bio-indicators of a water body, constituting the main food for the carnivorous and omnivorous fishes in the aquatic ecosystem. In the present work, a detailed analysis of zooplankton diversity along with variations in species, and seasonal abundance with average and total population density was carried out in different types of domestic sewage oxidation ponds. Similar analysis for a comparison was done in a freshwater control pond situated in Bhopal India. In this study out of 8 ponds, 4 were selected for zooplankton analysis two being primary and two being secondary sewage oxidation ponds and one freshwater control pond was selected for comparative analysis. The results indicated that the number of zooplankton in all ponds ranged from 162 to 14776 org/L, seasonally it was observed that the sewage oxidation ponds had the maximum population of zooplankton in winter, followed by rainy and summer seasons. Regarding the population of zooplankton in the individual oxidation ponds, it was found that sewage secondary pond IIIB had the maximum zooplankton followed by IIIA. Interesting observations on the cascading effects of physicochemical parameters on plankton dynamics, including the variations in the diel population of various species of zooplankton have been recorded. The phenomenon of plankton grazing in different types of domestic sewage ponds is being reported for the first time.

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Berglund, Olof, Per Larsson, Göran Ewald e Lennart Okla. "Bioaccumulation and differential partitioning of polychlorinated biphenyls in freshwater, planktonic food webs". Canadian Journal of Fisheries and Aquatic Sciences 57, n.º 6 (1 de junho de 2000): 1160–68. http://dx.doi.org/10.1139/f00-045.

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The planktonic food chain phytoplankton - zooplankton - young-of-the-year roach (Rutilus rutilus) was studied in 19 lakes in southern Sweden to investigate the bioaccumulation of polychlorinated biphenyls (PCBs). The ΣPCB concentrations did not steadily increase with increasing trophic level. The ΣPCB concentrations in zooplankton (400 ng·g lipid-1) were lower than in both phytoplankton (660 ng·g lipid-1) and fish (890 ng·g lipid-1), which did not differ significantly. Lipid content explained 40% of the total variation in dry weight normalised ΣPCB concentrations in the samples. The PCBs were differentially partitioned between the trophic levels. The logBMFs (biomagnification factors, concentration in predator/concentration in prey) were a function of the logKow of the PCB congeners. The logBMFzoo/phyto values were < 0 for all PCB congeners on a lipid weight basis, and the logBMFfish/zoo values were < 0 for PCB congeners with logKow > 6. We conclude that no PCBs had higher lipid-normalised concentrations in zooplankton than in phytoplankton and the most lipophilic PCBs had moderately higher concentrations in roach than in zooplankton. PCBs with logKow > 6 decreased in concentration from phytoplankton to zooplankton to roach. We suggest that the concept of biomagnification did not apply to the planktonic food chain investigated in these lakes.

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Bunnell, David B., María J. González e Roy A. Stein. "Zooplankton biomass enhances growth, but not survival, of first-feeding Pomoxis spp. larvae". Canadian Journal of Fisheries and Aquatic Sciences 60, n.º 11 (1 de novembro de 2003): 1314–23. http://dx.doi.org/10.1139/f03-112.

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We used otoliths to estimate growth and survival of white (Pomoxis annularis) and black (Pomoxis nigromaculatus) crappie larvae in five Ohio reservoirs. Because Pomoxis spp. larvae are among the smallest freshwater larvae and competition with gizzard shad larvae (Dorosoma cepedianum) is likely, we hypothesized that first-feeding Pomoxis spp. larvae would be susceptible to slow growth and starvation. We estimated survival by comparing proportional weekly cohort distributions of Pomoxis spp. larvae and juveniles. When distributions differed, a cohort survival index was evaluated against density of appropriately sized zooplankton biomass (crustaceans and rotifers), as well as temperature, turbidity, and density of all limnetic larvae that occurred during hatch week, when exogenous feeding began. Growth of first-feeding larvae (<10 days old) increased with total zooplankton biomass (r2 = 0.64); growth of larvae aged 10–16 days was unrelated to all measured variables. Survival was positively correlated with zooplankton biomass in only one of four reservoirs, and other variables did not correlate as expected. This result casts doubt on whether zooplankton contributes to survival of freshwater larvae.

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Ostojic, Aleksandar. "New and rare taxa of freshwater zooplankton in the fauna of Yugoslavia". Archives of Biological Sciences 54, n.º 3-4 (2002): 87–95. http://dx.doi.org/10.2298/abs0204087o.

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Analysis of the faunistic composition of Zooplankton in two reservoirs for watersupply nearby Kragujevac indicated a relatively great diversity. Qualitative analysis of Zooplankton composition in the Grosnica reservoir demonstrated the presence of 105 laxa, whereas somewhat fewer taxa (99) were recorded in the Gruza reservoir. Most of the taxa recorded in both reservoirs are cosmopolitan organisms. Small number of recorded taxa have been rarely registered in the territory of Serbia till present. The following species from the group of Rotatoria can be mentioned as being probably found for the first time in waters of our country: Dicranophorus rostralus, Philodina aadicomis and Trichocerca jenningsi. All three of these species were recorded only in the Grosnica reservoir. Only inspection of the complete literature on Zooplankton in our country could confirm with certainty that the Grosnica reservoir is the first record of these three species in the territory of Serbia. However, even such data as our represents a contribution to the knowledge on diversity of the Zooplankton fauna of Serbia.

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Rakowski, Chase J., e Mathew A. Leibold. "Beyond the fish-Daphnia paradigm: testing the potential for pygmy backswimmers (Neoplea striola) to cause trophic cascades in subtropical ponds". PeerJ 10 (28 de setembro de 2022): e14094. http://dx.doi.org/10.7717/peerj.14094.

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Trophic cascades, or indirect effects of predators on non-adjacent lower trophic levels, are a classic phenomenon in ecology, and are thought to be strongest in aquatic ecosystems. Most research on freshwater trophic cascades focused on temperate lakes, where fish are present and where Daphnia frequently dominate the zooplankton community. These studies identified that Daphnia often play a key role in facilitating trophic cascades by linking fish to algae with strong food web interactions. However, Daphnia are rare or absent in most tropical and subtropical lowland freshwaters, and fish are absent from small and temporary water bodies, where invertebrates fill the role of top predator. While invertebrate predators are ubiquitous in freshwater systems, most have received little attention in food web research. Therefore, we aimed to test whether trophic cascades are possible in small warmwater ponds where Daphnia are absent and small invertebrates are the top predators. We collected naturally occurring plankton communities from small fishless water bodies in central Texas and propagated them in replicate pond mesocosms. We removed zooplankton from some mesocosms, left the plankton community intact in others, and added one of two densities of the predaceous insect Neoplea striola to others. Following an incubation period, we then compared biomasses of plankton groups to assess food web effects between the trophic levels, including whether Neoplea caused a trophic cascade by reducing zooplankton. The zooplankton community became dominated by copepods which prefer large phytoplankton and exhibit a fast escape response. Perhaps due to these qualities of the copepods and perhaps due to other reasons such as high turbidity impairing predation, no evidence for food web effects were found other than somewhat weak evidence for zooplankton reducing large phytoplankton. More research is needed to understand the behavior and ecology of Neoplea, but trophic cascades may generally be weak or absent in fishless low latitude lowland water bodies where Daphnia are rare.

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Leech, Dina M., Troy L. Clift, Jessica L. Littlefield, Nicholas R. Ravagli e Jacob E. Spain. "Indirect versus direct effects of freshwater browning on larval fish foraging". Canadian Journal of Fisheries and Aquatic Sciences 78, n.º 7 (julho de 2021): 969–83. http://dx.doi.org/10.1139/cjfas-2020-0379.

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Fish foraging and energy flow between trophic levels are predicted to decline with freshwater browning due to decreased light availability. Studies investigating these predictions have focused on juvenile and adult fishes; however, the larval stage represents a “critical period” in development. We investigated the indirect (i.e., prey availability) versus direct (i.e., visual foraging) effects of browning on zooplankton–larval fish interactions by altering water colour with SuperHume (absorbance at 440 nm = 1.6–10.8 m−1). Phytoplankton and zooplankton densities were monitored across treatments for 1 month to simulate the time leading up to fish spawning in the spring. Larval largemouth bass (Micropterus salmoides) were then introduced to assess indirect effects on fish feeding, growth, and survival. Direct effects on largemouth bass and bluegill (Lepomis macrochirus) foraging on zooplankton were determined with separate short-term experiments. Browning did not directly alter the ability of larvae to capture prey. However, indirect effects on larval fish foraging, growth, and survival were observed as phytoplankton and zooplankton abundance decreased with increased browning. Our data suggest browning may reduce energy transfer to larval fish due to a reduction in prey but not visual foraging.

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López, Carlos, Enrique Ochoa, Rita Páez e Solange Theis. "Epizoans on a tropical freshwater crustacean assemblage". Marine and Freshwater Research 49, n.º 3 (1998): 271. http://dx.doi.org/10.1071/mf96037.

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Prevalence and substrate specificity of epizoans on crustacean zooplankton were examined during an annual cycle in Tulé Reservoir, a large, shallow and polymictic waterbody in western Venezuela. Epistylis sp., a ciliate protozoan, and Synedra sp., a pennate diatom, were the most frequent epibiont taxa. The prevalence of all epibionts on 1800 individual crustaceans was only 3.3%, and the occurrence of the two epibiotic taxa together on the same substrate zooplankter was low (3.3% of total infested crustaceans). Cyclopoid copepods were preferred as substrate for Epistylis sp. Neither epibiont taxon was found on copepodids or adults of a calanoid. Both epibionts were absent in the early rainy season but appeared in mid rainy season and showed the highest prevalence in the early dry season. During the remainder of the dry season prevalence was low. Epibiont prevalence was not related to presence or absence of zooplankton taxa or water temperature. Differences from temperate epibiont communities are discussed Resumen. A lo largo de un ciclo anual, se estudió la prevalencia y la especificidad al sustrato de los epibiontes de la comunidad de crustáceos planctónicos del Embalse Tulé, un cuerpo de agua somero y polimictico del Occidente de Venezuela. Epistylis sp., un protozoario ciliado, y Synedra sp., una diatomea pennada, fueron los taxones más frecuentes. La prevalencia de ambos epibiontes en conjunto sobre los 1.800 individuos examinados fue de 3,3% y la presencia de ambos epibiontes en el mismo sustrato fue baja (3,3% del total de individuos infestados). Los copépodos ciclopoideos fueron preferidos por Epistylis como sustrato. Ningún epibionte se observó en los copépodos calanoides. Los epibiontes aparecieron a mediados del período de lluvias y alcanzaron su máxima prevalencia al principio del período de sequía. La prevalencia no se encontró relacionada ni con la presencia o ausencia de las especies zooplanctónicas ni con la temperatura del agua. En el presente trabajo se realizan comparaciones con las comunidades epibiónticas de la zona templada y se discuten explicaciones a las diferencias encontradas.

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Caumette, G., I. Koch, K. House e K. J. Reimer. "Arsenic cycling in freshwater phytoplankton and zooplankton cultures". Environmental Chemistry 11, n.º 5 (2014): 496. http://dx.doi.org/10.1071/en14039.

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Environmental context Understanding how arsenic is changed from toxic to non-toxic chemical forms in lakes and rivers is important in understanding the overall risk from arsenic. Freshwater plankton exposed in laboratory cultures to different sources of toxic inorganic arsenate formed arsenosugars, but at higher exposure levels, in water and through contaminated sediment, inorganic arsenate remained unchanged. In arsenic-contaminated freshwater bodies, plankton may provide a source of toxic inorganic arsenic to consumers. Abstract Freshwater phytoplankton (Chlamydomonas) and zooplankton (Daphnia pulex) were exposed to arsenic to trace the arsenic transformations and the formation of organoarsenic compounds at the base of the freshwater food chain. Plankton were cultured in artificial lake water, and exposed to arsenic through several pathways, hypothesised to be the main exposure sources: through water, food and contaminated sediments. High performance liquid chromatography–inductively coupled plasma–mass spectrometry and X-ray absorption spectroscopy were used to determine arsenic speciation in the studied organisms, and X-ray fluorescence mapping was used to locate the arsenic in a single Daphnia specimen. The results show that the formation of methylated arsenic compounds and arsenosugars by the zooplankton organisms was independent of the exposure route, but instead dependent on arsenic concentration in the environment. Specifically, organoarsenic compounds were dominant in extracts of Daphnia organisms exposed to low arsenic concentrations through water at 10µgL–1 (67%), and through contaminated food (75%), but inorganic arsenic was dominant in Daphnia exposed to high arsenic concentrations, including contaminated sediments. Phytoplankton cultures contained variable amounts of arsenosugars, but on average the dominant compound in phytoplankton was inorganic arsenic. The main implications of the present study for understanding arsenic cycling in the freshwater plankton community are that arsenosugars are formed at possibly both the phytoplankton and zooplankton trophic levels; and that higher arsenic loads in plankton correspond to higher inorganic arsenic concentrations, which could indicate a saturation of the arsenic methylation process by plankton organisms.

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Dela Paz, Erica Silk P., Mark Louie D. Lopez, Christian Irvin Harvey A. David, Dave Ryan A. Dela Cruz, Gian Alfonso A. Viernes, Jac Fritgerald Wong e Rey Donne S. Papa. "Freshwater microcrustaceans (Cladocera: Anomopoda and Ctenopoda, Copepoda: Cyclopoida and Calanoida) in the highly urbanized Metropolitan Manila area (Luzon, Philippines)". Check List 14, n.º 5 (14 de setembro de 2018): 751–62. http://dx.doi.org/10.15560/14.5.751.

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Despite the increasing interest in studying Cladocera and Copepoda in Philippine freshwaters, there is a need to update our knowledge on its taxonomy and distribution in highly urbanized areas, such as Metropolitan Manila. This paper presents an updated listing of freshwater microcrustaceans and their distribution in Metropolitan Manila, considering the continued deterioration of water quality and increased urbanization in many areas since the last comprehensive study on these taxa in 1950s. We collected water samples from 33 freshwater sites in Metropolitan Manila and 23 of which were found to contain microcrustacean zooplankton. A total of 13 species were identified including two new locality records for C. cornuta and D. dubium in Pasig River. All 8 cladocerans, we identified have already recorded in previous studies while 3 cyclopoid copepods are new records for Metropolitan Manila. Furthermore, 16% of all known freshwater microcrustacean zooplankton species in the Philippines are found in Metropolitan Manila, including the Luzon-endemic Filipinodiaptomus insulanus collected from man-made reservoirs in less-disturbed habitats (an urban wildlife park, golf course and eco-park). Other identified species such as Thermocyclops taihokuensis may serve as indicator for high levels of nutrient. These results point to the importance of monitoring urban aquatic biodiversity for their potential in determining aquatic ecosystem health and of maintaining urban aquatic sanctuaries which may serve as alternative habitat for flora and fauna in rapidly developing urban centers such as Metropolitan Manila.

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Truong, Trinh Si Hai, e Vinh Tam Nguyen. "Zooplankton biodiversity in the biosphere reserve of Cu Lao Cham - Hoi An, 2015–2016". Tạp chí Khoa học và Công nghệ biển 19, n.º 4A (8 de novembro de 2019): 273–85. http://dx.doi.org/10.15625/1859-3097/19/4a/14609.

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Zooplankton samples in the biosphere reserve of Cu Lao Cham - Hoi An were collected at 20 stations belonging to 3 ecosystems: Mangrove palm - seagrass, transition area and coral reef in rainy season (11/2015) and dry season (6/2016) to determine biodiversity of the biosphere reserve of Cu Lao Cham - Hoi An. 161 species belonging to 16 zooplankton groups were recognized, copepoda was a dominant group with 92 species, followed by cladocera (15 species) and tunicata (13 species). Mangrove palm - sea grass had a different zooplankton structure compared with transition area and coral reef with a lower number of species and similarity index about 40%. The average density of zooplankton in study areas in dry season (24,559 ± 24,700 inds.m-3) were 4 times higher than in rainy season (6,124 ± 6.554 inds.m-3) and dominated by copepoda. The euryhaline cladocera (Bosmina longirostris), freshwater cladocera (Ceriodaphnia rigaudi) and freshwater copepoda (Microcyclops varicans) were dominant in mangrove palm - seagrass ecosystem. Meanwhile, in coral reef ecosystem, the small copepods (genus Oncaea, Oithona) and Tunicata were dominant. Biodiversity indices were low in mangrove - palm and increase from transition area to coral reef ecosystem.

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Rojo, Carmen, María A. Rodrigo, Guillem Salazar e Miguel Álvarez-Cobelas. "Nitrate uptake rates in freshwater plankton: the effect of food web structure". Marine and Freshwater Research 59, n.º 8 (2008): 717. http://dx.doi.org/10.1071/mf08023.

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Nitrate incorporation rates by primary producers and the transfer of nitrogen to upper planktonic food web levels in different seasons (spring and summer of different years) were studied using a microcosm experimental approach. The study communities were natural plankton communities from Colgada Lake (central Spain), which is heavily polluted by nitrate. Natural δ15N in phytoplankton and zooplankton was measured and experiments were performed on the 15N supply. Naturally derived δ15N varied from 7.4 to 8.6‰ and from 10.0 to 16.8‰ in phytoplankton and zooplankton respectively. Nitrogen incorporation rates ranged from 0.006 to 0.036 μM h–1 and from 0.0004 to 0.0014 μM h–1 in phytoplankton and zooplankton respectively. The differences in natural δ15N levels and nitrogen incorporation rates between plankton fractions from seasonally different communities reported in the present study suggested that the nitrogen uptake by planktonic communities in Colgada Lake depend on different combinations of dominant zooplankters and phytoplankton size structure. A higher level of nitrogen uptake by phytoplankton occurred when small algae were dominant without competitors (larger algae) or main predators (herbivorous zooplankters). This was because copepods, with the lowest zooplankton nitrogen uptake, were dominant. Phytoplankton nitrogen uptake was lower when big algae were dominant.

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Cavaletto, Joann F., Henry A. Vanderploeg e Wayne S. Gardner. "Wax esters in two species of freshwater zooplankton". Limnology and Oceanography 34, n.º 4 (junho de 1989): 785–89. http://dx.doi.org/10.4319/lo.1989.34.4.0785.

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Andersen, Tom, e Dag O. Hessen. "Carbon, nitrogen, and phosphorus content of freshwater zooplankton". Limnology and Oceanography 36, n.º 4 (junho de 1991): 807–14. http://dx.doi.org/10.4319/lo.1991.36.4.0807.

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Diel, Patricia, Marvin Kiene, Dominik Martin-Creuzburg e Christian Laforsch. "Knowing the Enemy: Inducible Defences in Freshwater Zooplankton". Diversity 12, n.º 4 (7 de abril de 2020): 147. http://dx.doi.org/10.3390/d12040147.

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Phenotypic plasticity in defensive traits is an appropriate mechanism to cope with the variable hazard of a frequently changing predator spectrum. In the animal kingdom these so-called inducible defences cover the entire taxonomic range from protozoans to vertebrates. The inducible defensive traits range from behaviour, morphology, and life-history adaptations to the activation of specific immune systems in vertebrates. Inducible defences in prey species play important roles in the dynamics and functioning of food webs. Freshwater zooplankton show the most prominent examples of inducible defences triggered by chemical cues, so-called kairomones, released by predatory invertebrates and fish. The objective of this review is to highlight recent progress in research on inducible defences in freshwater zooplankton concerning behaviour, morphology, and life-history, as well as difficulties of studies conducted in a multipredator set up. Furthermore, we outline costs associated with the defences and discuss difficulties as well as the progress made in characterizing defence-inducing cues. Finally, we aim to indicate further possible routes in this field of research and provide a comprehensive table of inducible defences with respect to both prey and predator species.

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Wasarat, Mohd, e Rajendra Chauhan. "Freshwater Zooplankton diversity of Halali reservoir A Review". International Journal of Scientific Research in Biological Sciences 5, n.º 6 (1 de janeiro de 2019): 196–98. http://dx.doi.org/10.26438/ijsrbs/v5i6.196198.

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Pinel-Alloul, Bernadette, Théophile Niyonsenga, Pierre Legendre e G. Gril. "Spatial and environmental components of freshwater zooplankton structure". Écoscience 2, n.º 1 (janeiro de 1995): 1–19. http://dx.doi.org/10.1080/11956860.1995.11682263.

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Flores, Luigi Naselli, Rossella Barone e Mario Zunino. "Distribution patterns of freshwater zooplankton in Sicily (Italy)". SIL Proceedings, 1922-2010 26, n.º 4 (maio de 1998): 1973–80. http://dx.doi.org/10.1080/03680770.1995.11901088.

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Hanazato, T. "Pesticide effects on freshwater zooplankton: an ecological perspective". Environmental Pollution 112, n.º 1 (2001): 1–10. http://dx.doi.org/10.1016/s0269-7491(00)00110-x.

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Kâ, Samba, Juana Mireya Mendoza-Vera, Marc Bouvy, Gisèle Champalbert, Rose N’Gom-Kâ e Marc Pagano. "Can tropical freshwater zooplankton graze efficiently on cyanobacteria?" Hydrobiologia 679, n.º 1 (25 de agosto de 2011): 119–38. http://dx.doi.org/10.1007/s10750-011-0860-8.

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