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1
Kirkwood, Richard Christopher. "Interactions between fish, Mysis, and zooplankton in Lough Neagh". Thesis, University of Ulster, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268119.
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2
Jarvis, Andrew Charles. "Studies on zooplankton feeding ecology and resource utilization in a sub-tropical hypertrophic impoundment (Hartbeespoort Dam, South Africa)". Thesis, Rhodes University, 1988. http://hdl.handle.net/10962/d1004600.
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Various aspects of the feeding ecology of zooplankton are described for hypertrophic Hartbeespoort Dam, where the phytoplankton is dominated by the cyanophyte Microcystis. The study considers zooplankton succession, community grazing rates, and speciesspecific filtration rates on Microaystis colonies and natural bacterioplankton. Seasonal abundance of the main herbivorous zooplankton between 1981 and 1986 is described both in respect of biomass and specific densities. In situ community grazing rates were measured from January 1983 to March 1985 using 14C-Iabelled Chlorella . Zooplankton succession and community grazing rates are examined in relation to food quantity and quality. Experiments measuring species-specific filtration rates on labelled Chlorella and Microcystis colony fractions revealed low filtration rates for small-bodied cladoceran species on cyanophyte colonies. Daphnia fed significantly on Microcystis colonies up to 60-100 ).μm but Daphnia filtration rates on Chlorella were suppressed by ~707. during the mid-summer increase in Microcystis abundance. Filtration rates of small cladoceran species were not suppressed by MicpocystisJ which was not an important food resource . Cladoceran filtration rate:body length models were developed for Chlorella and Microcystis colony fractions as food. Multiple regression models explained variance in filtration rates on these foods as a function of body length, food type and size, grazer species and temperature (in order of significance). Inclusion of food quality factors such as cyanophyte colony size seems justified in models of plankton feeding in eutrophic or hypertrophic lakes. Methods for in situ measurement of zooplankton filtration rates on 'H-thymidine-Iabelled natural bacteria were improved for use under hypertrophic conditions, and associated isotope-adsorption errors were measured. Community, species-specific and length-specific filtration rates on bacterioplankton were measured (late-spring to late-summer 1986-87) . Ceriodaphnia exhibited no preference for bacteria or Chlorella. Other cladocerans preferred the algal food . Algal/bacterial selectivity coefficients of the zooplankton community revealed an increased algal preference following the mid-summer shift to phytoplankton dominance by largely inedible Microcystis. This implies that bacterioplankton is not an important food resource for the summer cladoceran community. Estimates of the contribution of bacterial carbon to the daily zooplankton carbon requirements are low. The implications of all results are discussed in relation to seasonal succession, the clear-water phase', and biomanipulation in this hypertrophic reservoir.
3
McKee, Dermot. "The influence of temperature on some of the life history, behaviour and population characteristics of #Daphnia magna'". Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283667.
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Treuner, Anke Britt. "Ecotoxicology of neotropical freshwater zooplankton species exposed to toxic mixtures". Thesis, University of Stirling, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.720351.
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5
Rowe, Chad L. "Global distribution, phylogeny and taxonomy of the freshwater zooplankton genus Holopedium". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0015/MQ55709.pdf.
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Moats, Kenneth M. "Microzooplankton composition and dynamics in Lake Erie". Connect to this title online, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1145290028.
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7
Phillips, Sheri A. "Changes in the summer zooplankton community of the Indiana waters of Lake Michigan inshore at a Michigan City transect, 1987 and 1988". Virtual Press, 1993. http://liblink.bsu.edu/uhtbin/catkey/865935.
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Alterations in the summer zooplankton community that have appeared since Johnson's (1972) study of a Michigan City (site M) transect in southeastern Lake Michigan were investigated. Vertical tows were made at 5, 10, 15, and 18 meters from June through August in 1987 and 1988 in order obtain data that could be compared with that of Johnson (1972).Subsamples analyzed were proportionately larger than those of Johnson (1972), in order to obtain a detailed profile of the species and numbers in the community, and to identify large, predatory zooplankton species that are believed to have been severely impacted by the explosive growth of the alewife population during the 1960's.The most common crustacean species collected were: Diacyclops thomasi, Leptodiaptomus minutus, Leptodiaptomus ashlandi, calanoid and cyclopoid nauplii and copepodids, Daphnia retrocurva, and Bosmina longirostris. The most common rotifer species collected were Keratella c. cochlearis, Keratella crassa, Kellicottia longispina, Conochilus sp., and Polyarthra sp.. Higher numbers of Epischura lacustris adults and copepodids, Leptodora kindti, Mesocyclops edax, Daphnia galeata mendotae, and the rotifers Asplanchna priodonta, Conochilus sp., Keratella crassa, and Ploesoma truncatum were recorded as compared to Johnson's 1972 data. The summer zooplankton community of this transect appears to have been represented in the summers of 1987 and 1988 by a greater number of large crustacean zooplankton species, as opposed to a 1970 community dominated by small microfiltrators and D. thomasi.Department of Biology
8
Yu, Riqing. "Metal uptake, assimilation and stoichiometric effects in daphnia magna /". View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202002%20YUR.
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9
Duerr, Jennifer Christine. "Microzooplankton grazing on cyanobacteria in Vancouver Lake, Washington, USA". Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/j_duerr_121609.pdf.
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Thesis (M.S. in environmental science)--Washington State University, December 2009.Title from PDF title page (viewed on Feb. 18, 2010). "School of Earth and Environmental Sciences." Includes bibliographical references (p. 40-45).
10
Westcott, Kim. "Environmental factors affecting methyl mercury accumulation in zooplankton". Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23305.
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Filter-feeding macrozooplankton were collected from 24 lakes in south-central Ontario to examine relationships between environmental factors and methyl mercury accumulation. Zooplankton methyl mercury levels ranged from 19 to 448 ng$ rm cdot g sp{-1}$ dry weight in the study lakes and were highest in zooplankton from acidic brownwater lakes. Water color and lake water pH were the best predictors of methyl mercury levels in zooplankton explaining 73% of the variation. Methyl mercury concentrations were positively correlated with water color and inversely correlated with lake water pH. Water color explained a greater portion of the overall variance in methyl mercury levels, indicating that the supply of mercury from the drainage basin plays a key role in determining methyl mercury concentrations in the lacustrine biota. Zooplankton methyl mercury levels were well correlated with mercury concentrations in smallmouth bass (Micropterus dolomieui) and largemouth bass (Micropterus salmoides) from 11 of the study lakes showing zooplankton to be good indicators of the relative bioavailability of mercury at the base of the food chain.
11
Merrick, Chester John. "Phytoplankton-zooplankton interactions in Mt. Bold Reservoir, South Australia /". Title page, contents and summary only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phm568.pdf.
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Claska, Mary Elizabeth. "The distribution of zooplankton in selected Oregon lakes". PDXScholar, 1988. https://pdxscholar.library.pdx.edu/open_access_etds/3752.
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Zooplankton samples were collected from 166 Oregon lakes. The lakes included a wide range in size, trophic status, and water quality. Lakes were located throughout the state. Zooplankton were identified using standard taxonomic keys and counted. Seventy-four species were identified from the 200 total samples, including 32 species of cladocera, 22 copepods, and 11 rotifers. Two species of copepod were recorded for the first time in Oregon: Diaptomus mississippiensis and Diaptomus pallidus. Seven species had widespread distributions throughout most of the watersheds in the state. Seventeen other species had distributions restricted to eastern, central, or western Oregon. The remaining species were either rare or had random distributions.
13
Irvine, K. "Zooplankton ecology and the effects of nutrient additions, habitat structure and fish predation on a freshwater ecosystem". Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378900.
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Persson, Jonas. "Food Quality Effects on Zooplankton Growth and Energy Transfer in Pelagic Freshwater Food Webs". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7811.
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Jordan, Meredith Powers. "The Effects of Anthropogenic Stressors on Mercury Concentrations and Community Composition of Freshwater Zooplankton". PDXScholar, 2016. https://pdxscholar.library.pdx.edu/open_access_etds/3364.
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Methylmercury (MeHg) bioaccumulation in freshwater aquatic systems is impacted by anthropogenic stressors, including climate change and excess nutrients. The goal of this study was to determine how warmer water temperatures and excess nutrients would impact zooplankton communities and phytoplankton concentrations, and in turn increase or decrease MeHg concentrations in freshwater zooplankton. I used a 2x2 factorial design to determine if the interaction of temperature and nutrients would impact plankton metrics and zooplankton MeHg concentrations. Mesocosms were filled with Hg-contaminated water and plankton from Cottage Grove Reservoir, Oregon, a waterbody that has experienced decades of elevated MeHg concentrations and corresponding fish consumption advisories due to run-off from Black Butte Mine tailings, located within the watershed. Treatment combinations of warmer temperature (increased by 0.5°C) and nutrient addition (a single pulse of excess nitrogen and phosphorous), control, and a combination of temperature and nutrients were applied to mesocosms. While plankton did respond to treatments, zooplankton biomass and phytoplankton concentrations did not have significant relationships to MeHg concentrations. However, a significant interactive effect of nutrients and temperature was present: nutrients appeared to buffer against increased MeHg concentrations when temperature was elevated. The mechanisms for this interaction appear to be related to a shift to larger body size and an increase in abundance of Daphnia over copepods. Findings suggest that community composition and species-specific differences in both zooplankton and phytoplankton could play a role in MeHg transfer to higher trophic levels.
16
Sullivan, Christopher Lee. "Zooplankton, gizzard shad, and freshwater drum : interactions in a Great Plains irrigation reservoir / by Christopher Lee Sullivan". Kearney, Neb. : University of Nebraska-Kearney, 2009. http://www.nlc.state.ne.us/epubs/C2800/B007-2009.pdf.
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Knillmann, Saskia [Verfasser]. "The influence of competition on effect and recovery from pesticides in freshwater zooplankton communities / Saskia Knillmann". Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2013. http://d-nb.info/1044748974/34.
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CIUFFA, DANIELE. "Nutrients and fish effects on plankton community in freshwater mesocosms". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/962.
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Eutrophication affects many lakes in the world. Two important mechanisms to solve this problem are nutrient and fish control.
The main aim of the present work was to study nutrient and fish effects on plankton community in freshwater shallow lakes. Two mesocosm experiments were performed, one in spring and the other in winter to test differences in response of planktonic organisms to nutrient and fish addition in different seasons. The results would be of extremely importance for the management of these ecosystems.
Mesocosms were polyethylene bags filled with lake water and placed into the lake. Three different nutrient additions and three different fish densities were considered. All the possible combinations between these two factors were tested. Each mesocosm had a replicate, for a total of eighteen mesocosms in both seasons. Lake water was also sampled to test any differences between mesocosms and the natural ecosystem. Both experiments lasted six weeks. In the first week mesocosms were filled with lake water and nutrient and fishes were added. Each week, after sampling nutrients (nitrate and orthophosphate) were added. Fish used was Gambusia holbrooki mainly because its largely recognized planktivory. After the last week, benthic macroinvertebrates were sampled and stomach contents of fishes were analyses.
On the basis of the many studies demonstrating the significance to take into account functional groups of zooplankton, instead of consider total zooplankton density, in the present work four groups (rotifers, cladocerans, copepods and nauplii) were considered with regards to the zooplankton community.
Nutrients addition was associated to increase in phytoplankton biomass both in spring and winter although this increase was higher during spring. Nutrients did not affect zooplankton density neither in spring nor in winter. High fish density was associated to increase in phytoplankton biomass in both seasons. On zooplankton community, fish had a composite effect. They did not increase total zooplankton density neither in spring nor in winter. Fish changed zooplankton community. In spring, with increasing fish density rotifers increased while cladocerans and copepods decreased. In winter, zooplankton community was composed mainly by rotifers. Fish did not affect rotifers, but decreased cladocerans, copepods and nauplii. In spring, fishes could prey also on benthic macroinvertebrates. During winter, planktivory by fish was more intense due to the lack of benthic macroinvertebrates. Results show different response of plankton community between seasons. Results show the importance of considering as many variables as possible.
19
Moon, Cyle R. "Zooplankton phytoplankton interactions in the San Joaquin River, Ca". Scholarly Commons, 2013. https://scholarlycommons.pacific.edu/uop_etds/223.
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The dynamics of zooplankton and phytoplankton growth and interactions play a significant role in water quality (e.g., pH and dissolved oxygen [DO]) and the available food supply for higher order organisms in the San Joaquin River Delta. Algae have been shown to significantly impact DO concentrations in the Deep Water Ship Channel (DWSC) of the San Joaquin River (SJR) estuary. Zooplankton grazing is one of the important mechanisms that influence the fate and spatial distribution of algae, and therefore, may contribute to DO deficits that adversely impact aquatic habitat and salmonid migration in the SJR estuary. Numerical water quality models developed to simulate and predict dissolved oxygen in the SJR rely on mathematical algorithms that link chemical and biological mechanisms. Due to the complexity of natural systems, calibrating these models is challenging and often requires independent investigations to estimate input parameters, such as zooplankton grazing and algal growth rates. This investigation explored the applicability of three methods to quantify the rates that zooplankton graze on algae populations in the SJR. Zooplankton grazing studies were performed in the DWSC of the SJR from June 2012 through July 2013. Light and dark bottle microcosm studies using the dilution method, the food-removal method, and the grazer concentration method were tested. A modified microcosm approach similar to the grazer concentration method was developed that yielded changes in chlorophyll a concentrations that were sufficient to separate zooplankton grazing from algal growth and respiration. Microcosms contained zooplankton concentrations that were up to 30 times higher than natural, background levels. Zooplankton grazing rates were consistent in both magnitude and variability with literature values reported for other waters, ranging from 0.295-3.404-m 3 gC -1 d -1 and 0.006-1.413-m 3 gC -1 d -1 for light and dark bottle microcosms, respectively.
20
McGann, Brian Newton. "Recovery of Zooplankton Communities to Whole-Lake Disturbance". PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4344.
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Community assembly following disturbance is a key process in determining the composition and function of the future community. However, replicated studies of community assembly at whole ecosystem scales are rare. Here is described a series of whole-lake experiments in which the recovery of zooplankton communities is tracked following an ecosystem-scale disturbance. Fourteen lakes in eastern Washington were chosen: seven lakes were treated with rotenone, while the remaining seven were reference. Each lake was monitored up to six months before and one to two years after the rotenone treatments. Zooplankton tows were taken monthly, at a shallow, intermediate, and deep site in each lake, and were later enumerated and identified. A depth profile of environmental variables was taken at the deepest site. Community responses following disturbance were assessed using coarse metrics of abundance and diversity, community composition measures, and the relative importance of species traits was assessed by grouping taxa into functional groups. Communities were considered recovered if there was no significant difference between treatment and reference in zooplankton community metrics of abundance, diversity, and composition.
There was a steep decline in the abundance and diversity of the zooplankton community post-treatment. In many of the lakes, cyclopoid copepods, the group with a unique dormancy strategy, were the first group to recover, remained dominant for a few months, and may have exhibited priority effects advantages. Calanoid copepods were the slowest group to recover, perhaps due to their slow rate of development. There were varying recovery times and patterns between lakes, potentially based upon geographic location and severity of the winter season. These findings suggest that dormancy strategies, rate of development, and abiotic conditions following disturbance may be important in helping to understand recovery processes. Results of this study may give insight to disturbance ecology and the relative importance abiotic versus biotic characteristics that structure post-impacted communities.
21
Weaver, Meghan C. "Effects of Copper Sulfate Application on Zooplankton and Macroinvertebrate Communities in Upground Reservoirs". Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1339094079.
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22
Adams, Immaculata Brooke. "The effect of light and prey availability on the activity of the freshwater jellyfish, Craspedacusta sowerbii (Hydrozoan) /". Full-text of dissertation on the Internet (472 KB), 2009. http://www.lib.jmu.edu/general/etd/2009/Honors/Adams_ImmaculataB/adamsib_honors_11-10-2009.pdf.
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Cox, Andrea Joan. "Freshwater phylogeography, the impact of life history traits on the post-glacial dispersal of zooplankton in North America". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58330.pdf.
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Pasko, Susan R. "Limnetic Zooplankton Structure and The Impact of Invasion by an Exotic Cladoceran, Daphnia lumholtzi". Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1245294004.
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25
Katechakis, Alexis. "Selected interactions between phytoplankton, zooplankton and the microbial food web: Microcosm experiments in marine and limnic habitats". Diss., Connect to this title online, 2006. http://edoc.ub.uni-muenchen.de/archive/00005047/.
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Thesis (doctoral)--Ludwig-Maximilians-Universität München, 2006.Title from PDF t.p. (viewed on May 14, 2006). Includes reprints of papers co-authored with others. Vita. Includes bibliographical references.
26
Grange, Neil. "The influence of contrasting freshwater inflows on the feeding ecology and food resources of zooplankton in two eastern Cape estuaries, South Africa". Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1005400.
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The trophodynamic implications of reduced freshwater inflow on the zooplankton of eastern Cape estuaries was investigated by a comparison of the community composition and standing stocks, grazing rates and food resources of zooplankton in two systems, the Kariega and the Great Fish estuaries, which are subject to contrasting freshwater inflow. The climate of South Africa is semi-arid, and the low rainfall, coupled with high evaporative loss, result in the region having one of the lowest conversions of rainfall to run-off in the world. In addition, many of the major rivers are extensively impounded, consequently, estuaries often experience prolonged periods of zero or reduced freshwater inflow. The amount of freshwater available for estuarine management in the future is expected to decline as the demand for domestic, agricultural and industrial use increases. The influence of climate, tidal amplitude and wave action are essentially constant, consequently, the individual characteristics of an estuary are determined largely by the indirect influences of catchment size and regulation. Estuaries along the eastern Cape coast range from negative hypersaline systems, to positive systems in which a salinity gradient is well established. The Kariega estuary is a homogeneous marine estuary as a result of minimal freshwater inflow, whereas the Great Fish estuary receives sustained freshwater inflow and is partially-stratified. The quality and quantity of particulate food resources for suspension-feeders depended to a large extent on the allochthonous import of material associated with freshwater inflow. Nutrients, rather than light penetration of the watercolumn are the major factor limiting phytoplankton standing stocks. In the Kariega estuary, phytoplankton standing stocks were low (up to 1.0 μg l⁻¹) and the estuary is classified as oligotrophic. Correlation analyses indicated that lower quality detritus, originating from fringing macrophytes, may contribute substantially to suspended particulate organic material. Phytoplankton food resources were considerably higher in the Great Fish estuary (up to 21.8 μg ⁻¹) which is classified as mesotrophic/eutrophic, and correlation analyses indicated that phytoplankton comprised the dominant fraction of the particulate organic material. Although this suggested that the organic material was of a higher quality, the seston was "masked" by a higher suspended inorganic load. Consequently, the organic fraction comprised between 13 and 22% of total particulate material in the Great Fish estuary, compared with between 20 and 39% in the Kariega estuary. Food resources demonstrated a fairly uniform distribution along the length of the Kariega estuary and exhibited a slight seasonal increase during warmer months. By contrast, the point source influence of freshwater inflow resulted in a spatial gradient of food resources in the Great Fish estuary with higher values recorded towards the upper reaches. There was evidence that higher concentrations of particulate material in the upper reaches are also a consequence of hydrodynamic trapping. There was no marked seasonal pattern in the availability of food resources which were generally elevated in response to sporadic pulses of freshwater inflow. Tidal currents were responsible for elevating suspended food resources by re-suspension of material from the sediments. This effect was probably of greater importance in the Kariega estuary where food resources were generally limiting. In the Kariega estuary, the zooplankton community was dominated by calanoid copepods of the genera Acartia and Pseudodiaptomus. However, in the Great Fish estuary, the community was dominated by the mysid Mesopodopsis siabberi, and the calanoid P. hessei. Community biomass generally reflected the trophic status of the estuary. The mean seasonal biomass recorded in the Kariega estuary was 38 mg m⁻³ compared with 1597 mg m⁻³ in the Great Fish estuary. Greater spatial variability in community biomass was evident in the Great Fish estuary, partly in response to the food resource gradient, but also due to the inability of the mysid shrimps, which dominated the community biomass, to penetrate the lower salinity water of the upper reaches. Zooplankton in the Kariega estuary demonstrated a seasonal pattern of abundance whereas in the Great Fish estuary, community biomass was elevated in response to sporadic pulses of freshwater inflow. Grazing rates, measured in situ using a modified Gliwicz-Haney chamber, indicated that the zooplankton communities were capable of "clearing" substantial proportions of the watercolumn at certain times of the year. The pattern of grazing pressure over a diel cycle was examined in relation to the diel vertical migration movements of the zooplankton. Higher nighttime grazing rates were generally associated with the greater abundance of zooplankton resulting from the movement of zooplankton into the watercolumn after dusk, and their return to the sediments at dawn. Seasonal estimates of diel grazing pressure, extrapolated from daytime and nighttime feeding rates, indicated that the zooplankton "cleared" up to 40% of the watercolumn in a day in the Kariega estuary, and up to 120% d⁻¹ in the Great Fish estuary. However, values of around 25% d⁻¹ in the Kariega estuary, and 50 to 80% d⁻¹ in the Great Fish estuary, were not uncommon. Multiple regression analyses were used in an attempt to explain the influence of environmental factors on the variation in in situ grazing rates. These attempts were largely unsuccessful and the possible reasons, as well as recommended improvements to the methods used, are discussed. Seston concentration in the estuaries was highly variable as a result of the effects of tidal re-suspension and freshwater inflow. Consequently, further laboratory-based experiments were carried out to examine the influence of seston concentration on the filtration rates of the dominant calanoid copepods. Results indicated that some of the unexplained variability in the community filtration rates may be attributed to differences in species-specific response to changes in seston concentration.
27
Cescon, Cinzia Tatiana. "The 1996 population dynamics of microcrustacean zooplankton at Prairie Creek Reservoir in Delaware County, Indiana". Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1048368.
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This research was conducted to provide baseline data on the population dynamics of microcrustacean zooplankton at Prairie Creek Reservoir in Delaware County, Indiana from 24 January 1996 to 30 December 1996. This lake is a shallow lake (average depth <8m) used for recreational fishing and water supply for the local community. No published studies of zooplankton have previously been conducted at this location. I intended to test the hypothesis that Prairie Creek Reservoir has the same microcrustacean populations of shallow lakes in this region. The findings were compared to other studies in several North American lakes and reservoirs. Biotic and abiotic factors were considered as related to the population dynamics of zooplankton. Zooplankton serve as a critical forage base for many fish species, including several of economic importance. Increases and changes in species composition of zooplankton organisms associated with eutrophic conditions may also be an indication of deteriorating water quality (Gannon 1972). The data from this research suggest that Prairie Creek Reservoir has the typical zooplankton populations of a shallow, eutrophic North American lake. The presence of relatively high numbers of organisms generally associated with eutrophic environments, such as Bosmina longirostris, Leptodiaptomus siciloides, Acanthocyclops vernalis, and others supports this idea. The data from this study will be helpful to fisheries and environmental managers and will provide a baseline for future studies.Department of Biology
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Scharnberg, Larry Duane. "Zooplankton Community Structure in Lakes Near Mt. St. Helens, WA". PDXScholar, 1995. https://pdxscholar.library.pdx.edu/open_access_etds/5050.
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Eighteen lakes around Mt. St. Helens (MSH) were sampled for zooplankton from September '92 until September '94. Samples were enumerated and identified to the species level in most cases. Standard deviation and t-tests were performed to determine the precision of enumeration methods and replication of duplicate tows. Palatability indexes based upon predator preferences were developed and coupled with length-frequency analyses as indicators of predation pressure. The weighted means of the summer samples were then subjected to cluster analysis in an attempt to categorize lakes with respect to zooplankton community structure. Lastly, the community compositions and abundances of MSH lakes were compared to those in lakes on Mt. Rainier and Mt. Hood in an attempt to assess recovery of MSH lakes from the 1980 eruption. Results of analyses indicate the presence of three distinct groups of lakes: 1) A group of lakes with heavy predation resulting in simplified zooplankton communities dominated by Keratella, Ke/licottia, and sometimes cyclopoid species. Predation in these instances can be attributed to extremely high fish or Chaoborus abundance. 2) A second group of lakes characterized by great depth, high transparency, significant abundances of Diaptomus kenai, and moderate to light fish predation. These lakes support balanced zooplankton communities with substantial proportions of Daphnid and calanoid specimens attaining large size. Significant indications of size-specific niche differentiation among the cladocerans are notably absent from these first two groups. 3) A third group consists of lakes which appear to be more productive than the other two groups. This group has higher biovolumes of zooplankton in general, coexistence of several different sized cladoceran species, the highest diversity indices of all the lakes sampled, and moderate predation as indicated by length-frequency analysis. Two conclusions are drawn from the data. First, it appears that predation and primary productivity are both significant factors affecting the abundance and composition of MSH zooplankton communities. Additionally, these data document a significant overlap in zooplankton species in lakes near Mt. Rainier and Mt. Hood, suggesting that the zooplankton communities in lakes around MSH have recovered from the effects of the 1980 eruption.
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Ng, Patti A. "Trends in the nearshore zooplankton community in the Indiana waters of Lake Michigan, 1990-1996". Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1041923.
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Zooplankton samples collected May through August, 1990 to 1996 at site M, 15 m depth in the Indiana waters of Lake Michigan were examined for microcrustaceans, rotifers, and zebra mussel (Dreissena polymorpha) veligers. Abundance numbers per m3 were combined with Coffman's (1995) data to quantify recent trends in the zooplankton.Rotifers dominated the community, with Polyarthra vulgaris, Colurella, Keratella crassa, and K. cochlearis the most prevalent species. Copepods, primarily nauplii and copepodid forms, were the next most abundant taxa. Except for 1994 and 1995, Cladocera abundance was higher than zebra mussel veliger abundance. The cladoceran assemblage was dominated by Bosmina Iongirostris, with very few Daphnia noted. A precipitous decrease in zebra mussels veligers from 1994 to 1996 warrants further investigation to determine the nature and the extent of the population decline.Regression analysis of zebra mussel veliger abundance against abiotic and biotic factors demonstrated veligers varied directly with rotifer abundance and water column temperature and indirectly with cladoceran and yellow perch (Perca flavescens) abundance. A similar regression model of rotifer abundance revealed direct correlation with calanoid, cladoceran, zebra mussel veliger, and yellow perch abundance.Department of Biology
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Strecker, Angela Lee. "Responses of zooplankton community structure and ecosystem function to the invasion of an invertebrate predator, Bythotrephes longimanus". Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/454.
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Penczykowski, Rachel M. "Interactions between ecosystems and disease in the plankton of freshwater lakes". Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50368.
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I investigated effects of environmental change on disease, and effects of disease on ecosystems, using a freshwater zooplankton host and its fungal parasite. This research involved lake surveys, manipulative experiments, and mathematical models. My results indicate that ecosystem characteristics such as habitat structure, nutrient availability, and quality of a host’s resources (here, phytoplankton) can affect the spread of disease. For example, a survey of epidemics in lakes revealed direct and indirect links between habitat structure and epidemic size, where indirect connections were mediated by non-host species. Then, in a mesocosm experiment in a lake, manipulations of habitat structure and nutrient availability interactively affected the spread of disease, and nutrient enrichment increased densities of infected hosts. In a separate laboratory experiment, poor quality resources were shown to decrease parasite transmission rate by altering host foraging behavior. My experimental results also suggest that disease can affect ecosystems through effects on host densities and host traits. In the mesocosm experiment, the parasite indirectly increased abundance of algal resources by decreasing densities of the zooplankton host. Disease in the experimental zooplankton populations also impacted nutrient stoichiometry of algae, which could entail a parasite-mediated shift in food quality for grazers such as the host. Additionally, I showed that infection dramatically reduces host feeding rate, and used a dynamic epidemiological model to illustrate how this parasite-mediated trait change could affect densities of resources and hosts, as well as the spread of disease. I discuss the implications of these ecosystem–disease interactions in light of ongoing changes to habitat and nutrient regimes in freshwater ecosystems.
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Desgagné, Patrice. "Aspects de la productivité primaire et secondaire d'un réservoir hydroélectrique québécois, le Lac Saint-Jean /". Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1999. http://theses.uqac.ca.
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Wen, Yuan Hua. "Pharmacokinetic modeling of pollutant fluxes by limnoplankton". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34481.
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The objective of this thesis was to construct general models to predict pollutant fluxes in limnoplankton by incorporating characteristics of the organism and the structures of the chemical. A two-compartmental pharmacokinetic model was used to quantify the pollutant uptake, depuration and intercompartmental exchanges. The model pollutants were phosphorus and 22 organic chemicals.The rate constants of phosphorus uptake, excretion and intercompartmental changes by algae and cladocerans decreased with cell volume or body size raised to a power close to $-$0.25, except the intercompartmental exchanges for cladocerans which showed more negative slopes. In contrast, uptake, excretion and internal exchange rates per individual increased with cell size or body weight to a power similar to 0.75 with a similar exception for the cladoceran intercompartmental exchanges, which had slopes $<$0.75.
Bioconcentration factors, rate constants and flux rates of uptake and intercompartmental exchange from metabolic pool to structural pool of 22 $ sp{14}$C-labelled organic toxicants by Chlorella pyrenoidosa and Daphnia magna were positively correlated with the octanol/water partition coefficient, molecular weight, parachor, connectivity index, boiling point and melting point, and negatively with aqueous solubility. However, those of elimination and internal transfer from structural pool to metabolic pool showed opposite changes. Comparisons of pharmacokinetic parameters between Daphnia and Chlorella demonstrated that, although all kinetic parameters displayed similar patterns, the relative magnitudes of each corresponding parameters were significantly different between two species.
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Brittain, Jeffrey Thomas. "The Response of Zooplankton Communities in Montane Lakes of Different Fish Stocking Histories to Atmospheric Nitrogen Deposition Simulations". PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2394.
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Freshwater ecosystems are subject to a wide variety of stressors, which can have complex interactions and result in ecological surprises. Non-native fish introductions have drastically reduced the number of naturally fishless lakes and have resulted in cascading food web repercussions in aquatic and terrestrial habitats. Additional anthropogenic influences that result from increases in global airborne emissions also threaten wildlife habitat. Atmospheric nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of wilderness ecosystems. Planktonic communities have shown declines in response to predation and shifts in composition as a result of nutrient inputs and acidification, both of which are potential fates of nitrogen deposition. This study identified the response of zooplankton communities from two lakes (fish present vs. absent) in Mount Rainier National Park to manipulations simulating an episodic disturbance event in mesocosms. The experiment used a 2 x 2 factorial design with acid and nitrogen treatments. Treatments resulted in significantly elevated nitrogen and decreased pH conditions from control mesocosms over 42 days, indicating that the treatment effects were achieved. Results indicate that zooplankton communities from lakes with different food web structure respond differently to the singular effects of acid and nitrogen addition. Surprisingly, the interaction of the two stressors was related to increases in community metrics (e.g., abundance, biomass, body size, richness, and Shannon-Weiner diversity) for both lake types. This work can aid management decisions as agencies look to restore more aquatic montane habitats to their historic fishless states, and assess their abilities to recover and afford resistance to atmospheric pollution.
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Coffman, Curtis D. "Characteristics of the 1990-1994 zooplankton community at a sample location in Lake Michigan near Michigan City, Indiana, with emphasis on zebra mussel (dreissena polymorpha) dynamics". Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/941348.
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The Summer (May through August) community of crustacean zooplankton and zebra mussel (Dreissena polvmorpha) larvae at a 15 m sample site in Lake Michigan near Michigan City was evaluated for the years 1990 through 1994. Yearly mean densities were compared with investigations done at the same sample location by Johnson (1972) and Ball State University (unpublished data) during 1970 and 1971, respectively to investigate possible changes in community composition during the past 25 years. Potential declines in crustacean zooplankton relating to the 1991 introduction of the filter-feeding zebra mussel were also evaluated.Overall declines in major species since 1970-71 included Bosmina longirostris, Daphnia retrocurva, and Diacyclops thomasi. Recent increases in the nearshore fish population of alewife (Alosa pseudoharengus) and spottail shiner (Notropis hudsonius) may have influenced the densities of these species in recent years. Copepod nauplii were the only crustaceans to increase in overall abundance since the period of 1970-71, as the number of invertebrate predators appeared to decrease. Other species did not show any noticeable change in long-term abundance or during the 1990-94 period.Zebra mussel larvae were first observed in the zooplankton complex studied on June 17, 1991. -Densities of larvae reached maximal levels for the period of study in 1994 with two large reproductive pulses of 195,000 and 210,000/m3 in June and August, respectively. The mean abundance during 1994 made up 65% of the total crustacean zooplankton/zebra mussel community complex. Evaluation of the vertical stratification of zebra mussel larvae in 1994 revealed a strong (r2=0.75, p<0.0005) tendency for veligers to remain in the upper 10 m of the water column due to thermal stratification.Department of Biology
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Sgarzi, Serena. "Environmental and biotic factors influencing the size structure of the aquatic communities in Mediterranean ponds". Doctoral thesis, Universitat de Vic - Universitat Central de Catalunya, 2022. http://hdl.handle.net/10803/673519.
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Les basses mediterrànies són ecosistemes amb un alt valor ecològic, que pateixen
una forta regressió per les pressions antròpiques. No obstant això, l'atenció
científica rebuda sempre ha estat molt escassa, i la majoria dels estudis ecològics
s'han centrat en la seva biodiversitat, més que l'estructura de la mida corporal de
les seves comunitats. Les comunitats planctòniques i les poblacions del peix
endèmic i amenaçat Aphanius iberus (Valenciennes, 1846) es van analitzar en
basses costaneres permanents salobres (Capítol 1 i 2) i en basses temporànies
d'aigua dolça (Capítol 3). L'estructura de la mida es va estudiar mitjançant
diferents mètriques de mida (índex de diversitat de mida, espectre de mida,
longitud corporal mitjana) i es va aplicar a diferents escales ecològiques (grups
funcionals, nivell de població, considerant més d'un nivell tròfic a la vegada), per
esbrinar els principals factors ambientals i biòtics que determinaven l'estructura
de mides de les comunitats i poblacions aquàtiques a les basses mediterrànies.Mediterranean ponds are ecosystems with a high ecological value, suffering a strong regression due to anthropogenic pressures. Notwithstanding, the received scientific attention has always been far lesser than other larger water bodies. Most ecological studies on Mediterranean ponds have focused on their biodiversity, but only to a lesser extent they have paid attention to the body size structure of their communities. Planktonic communities and populations of the endemic and threatened fish Aphanius iberus (Valenciennes, 1846) were analyzed in brackish permanent coastal ponds (Chapter 1 and 2) and in temporary freshwater ponds (Chapter 3). Size structure was studied using different size metrics (e.g., size diversity index, size spectrum, mean body length, etc.) and applied at different ecological scales (i.e., functional groups, population level, more than one trophic level together), to unravel which were the main environmental and biotic drivers shaping the size structure of aquatic communities and populations in Mediterranean ponds.
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Wilkins, Keiko W. "The Importance of Dissolved Organic Matter Source on the Survival and Growth of Juvenile Daphnia". Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1578699709430677.
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Kane, Douglas D. "The development of a planktonic index of biotic integrity for Lake Erie". Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1092242571.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xxii, 277 p.; also includes graphics. Includes bibliographical references (p. 252-277). Available online via OhioLINK's ETD Center.
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Silva, Lidiane Cristina da. "Variação espacial e temporal da diversidade e biomassa da comunidade zooplanctônica do reservatório da UHE de Furnas-MG, Brasil". Universidade Federal de São Carlos, 2011. https://repositorio.ufscar.br/handle/ufscar/2008.
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Previous issue date: 2011-02-11Universidade Federal de Sao Carlos
The UHE Furnas Reservir is located in the state of Minas Gerais and it was built for hydroelectricity generation in 1963, although it is present used for multiple purposes. The zooplankton communities of freshwaters are composed by a variety of species belonging to several taxonomic (Cladocera, Copepoda, Rotifera, Protozoa, larvas de Insecta, Ostracoda, Turbellaria), and are all ecologically important. Many species can be indicators being highly sensitive of environmental conditions The aim of the present work was to analyse the spatial and temporal changes in the species composition, diversity and biomass of zooplankton community as well as their interactions with other environmental variables at the UHE Furnas Reservoir. Samplings were carried out each three months in 36 points in the reservoir, including the two major compartments: Sapucai and Grande dammed portions. Measurements of the main physical and chemical variables were carried out in situ and in the laboratory measurements of nutrients, suspended matter and chlorophyll a concentrations were performed. Zooplankton community was sampled by vertical net hauls with plankton net of 68 μm mesh size. Samples were analyzed regarding the species composition, numerical densities and community biomass. The results obtained indicated the water of the UHE Furnas Reservoir has oligotrophic conditions except in a locality upstream, in River Marimbondo compartment and others located distantly from the dam. The reservoir is thermally and chemically stratified regarding temperature and dissolved oxygen. There are also spatial changes and the reservoir can be divided in three major compartments: Sapucaí River compartment; central portion close to the dam and the northern River Grande compartment. Temporal fluctuations occurred for most variables, with strong differences among the dry and rainy periods. The species richness was high and some species were spatially segregated. Copepoda was the most abundant zooplankton group, both in numbers and biomass. The highest densities and biomass were found in the central portion of the reservoir during the rainy period. In general, the highest concentrations of chlorophyll, zooplankton density and biomass occurred in the Sapucaí River compartment, indicating its higher trophic condition as compared to the more oligotrophic River Grande compartment. Zooplankton biomass as a whole is low compared to other reservoirs, as expected for an oligotrophic system.
O reservatório da UHE de Furnas está situado em Minas Gerais e foi construído em 1963 para produção de energia elétrica, porém atualmente é utilizado para múltiplos fins. A comunidade zooplanctônica em águas doces é composta por um conjunto de organismos pertencentes a diversos grupos taxonômicos (Cladocera, Copepoda, Rotifera, Protozoa, larvas de Insecta, Ostracoda, Turbellaria), possui grande importância ecológica nos ambientes aquáticos e muitas espécies são utilizadas como bioindicadoras já que possuem grande sensibilidade ambiental. O objetivo desse trabalho foi analisar as variações espaciais e temporais da composição, diversidade e biomassa da comunidade zooplanctônica e suas relações com as variáveis ambientais do reservatório da UHE de Furnas. As amostragens foram trimestrais em 36 pontos do reservatório, incluindo os dois grandes compartimentos: rio Sapucaí e rio Grande. Medidas das principais variáveis físicas e químicas foram realizadas in situ e em laboratório foram determinadas as concentrações de nutrientes, material em suspensão e clorofila a. Amostras de zooplâncton foram coletadas por arrastos verticais através de uma rede de plâncton com malha de 68 μm. Foram analisadas a composição de espécies, densidade numérica e biomassa da comunidade. Os resultados indicam que o reservatório da UHE de Furnas possui condições oligotróficas com exceção da localidade situada na região represada do rio Marimbondo e localizadas às montantes da barragem. O reservatório é termicamente e quimicamente estratificado demonstrado pelos perfis de temperatura e oxigênio dissolvido. Existem variações espaciais podendo ser dividido em três porções: montante do compartimento rio Sapucaí, parte central próxima à barragem e montante do compartimento rio Grande. Variações temporais também foram verificadas para a maioria das variáveis analisadas, relacionadas ao verão chuvoso e inverno seco. A riqueza de espécies foi grande e algumas espécies apresentaram padrão espacial de ocorrência. O grupo Copepoda foi mais abundante em relação aos demais grupos tanto em densidade quanto em biomassa. Maiores densidades numéricas e biomassas foram registradas no período chuvoso e na parte central do reservatório. Maiores concentrações de clorofila a, densidade e biomassa zooplanctônicas foram registradas nos pontos localizados no compartimento rio Sapucaí quando comparado ao compartimento rio Grande. A biomassa zooplanctônica do reservatório da UHE de Furnas é baixa quando comparada a outros reservatórios como esperado para um sistema oligotrófico.
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Ormiston, Anna Kathleen. "ENVIRONMENTAL, SPATIAL AND TEMPORAL EFFECTS ON MICROBIAL COMPOSITION IN LAKE ERIE". Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1461444253.
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Bourdier, Gilles. "Composition biochimique du materiel particulaire lacustre : interets pour l'etude de l'activite metabolique des microorganismes, de la dynamique des populations phytoplanctoniques et des relations trophiques phyto-zooplancton". Clermont-Ferrand 2, 1989. http://www.theses.fr/1989CLF21119.
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Dans le but de preciser l'interet que presente la determination de la composition biochimique du materiel particulaire lacustre, pour l'etude de l'activite metabolique des microorganismes, la dynamique des populations phytoplanctoniques et les relations trophiques phyto-zooplanctoniques, une etude a court terme puis a long terme de la composition en acide gras des lipides phytoplanctoniques est menee. Ces acides gras sont ensuite utilises comme marqueurs organiques, pour suivre le transfert de matiere organique au sein du reseau trophique. Une demarche nouvelle est proposee par l'etude des relations trophiques phyto-zooplancton
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Rahayu, Ucu. "The influence of dissolved organic carbon (DOC) and calcium on the toxicity of copper and nickel to the freshwater alga Selenastrum capricornutum and the zooplankter Daphnia magna". Thesis, University of Ottawa (Canada), 2000. http://hdl.handle.net/10393/9241.
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The toxicity of copper and nickel was measured in algal cultures of Selenastrum capricornutum and zooplankton cultures of Daphnia magna to determine if dissolved organic carbon (DOC) and/or calcium concentrations can influence toxicity of these two metals. Water samples were collected from the Raisin River (high DOC and high calcium), the St. Lawrence River (low DOC and high calcium), the Ottawa River (medium DOC and calcium) as well as two lakes in Nova Scotia. The concentration sufficient to kill half the population of Daphnia magna after 48h of exposure (LC50), and the inhibition of cell growth of S. capricornutum after 72 h of exposure (IC50) were used to determine the sensitivity of these species to copper or nickel toxicity in these 5 water samples. In Part 3, I showed that the protection against copper or nickel toxicity was reduced with UVB radiation even though the total DOC was reduced by only 18%. The role of EDTA in the toxicity of copper and nickel on S. capricornutum was investigated in part 4. (Abstract shortened by UMI.)
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Lacroix, Gérard. "Ecologie des peuplements de cladoceres des gravieres en eau". Paris 6, 1987. http://www.theses.fr/1987PA066466.
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Marvalin, Olivier. "ABONDANCEcr, BIOMASSE, ACTIVITE ET RELATIONS TROPHIQUES DES COMMUNAUTES BACTERIENNES HETEROTROPHES DU LAC D'AYDAT (PUY DE DOME) : contribution a l'etude du fonctionnement des systemes aquatiques". Clermont-Ferrand 2, 1988. http://www.theses.fr/1988CLF21086.
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REY, ESPINASSE JEANNE. "Contribution a l'etude du zooplancton d'altitude et de la taxonomie des cladoceres". Toulouse 3, 1986. http://www.theses.fr/1986TOU30185.
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Etude consacree dans la premiere partie a la taxonomie et a la biogeographie des eladoceres du lac tchad et du bassin moyen de l'orenoque. Une deuxieme partie etudie le zooplancton de 9 lacs d'altitude des pyrenees (cladoceus et copepodes) notamment la repartition des especes, leur cycle evolutif regi par le facteur thermique, la dynamique des populations
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Seaman, M. T. "A zooplankton study of Hartbeespoort Dam". Thesis, 2014. http://hdl.handle.net/10210/11141.
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Pantel, Jelena Holly. "The interface between metacommunity ecology and microevolution in freshwater zooplankton". Thesis, 2009. http://hdl.handle.net/2152/ETD-UT-2009-12-447.
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In many habitats, species’ traits correspond strongly to local environmental conditions. The cause of this pattern may be in-situ evolution, where initially mal-adapted resident species evolved traits that increased their fitness. Alternatively, species with suitable traits may have colonized the focal habitat and replaced resident species. Since theories in the fields of evolutionary biology and community ecology developed independently, few guidelines tell us when to expect evolutionary adaptation or ecological species replacement as the primary driver of species and trait composition in a given habitat.
The goal of my dissertation research was to explain how evolutionary adaptation and ecological species replacement together determine the composition of pond zooplankton communities. I combined theoretical models with thorough surveys of natural pond communities and manipulative experiments. I discovered that one particular zooplankton species, Daphnia pulex, evolved to have different trait values in ponds with different environments. The evolutionary divergence within D. pulex profoundly affected its ecological interactions with other zooplankton species. D. pulex populations diverged from one another so much that they differed in their ability to successfully colonize ponds full of competing zooplankton species. I also used a computer simulation model to determine when a community’s trait changes were explained by evolutionary adaptation or ecological species replacement. The dispersal rate of species among habitats and the amount of genetic variance within these species both influenced adaptive trait change in a community.
The group of research studies that indicate evolutionary and ecological processes operate on a similar time scale is small but growing. My dissertation research provides another crucial demonstration that evolution within individual species, such as D. pulex, influences their community ecological interactions with other species. I also identified key parameters (dispersal rate among and genetic variance within species) that may help biologists predict whether evolution or ecological species replacement explained adaptive trait change.
My projects mostly concern the community and trait distributions that result from the assembly of species in new habitats. However, this framework may inform studies of community response to environmental changes such as invasive species or habitat destruction.text
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Leech, Dina Michelle. "Tolerance and behavioral responses of freshwater zooplankton to UV radiation /". Diss., 2001. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3010413.
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Clauser, Aaron Strohecker. "Zooplankton to amphibians : sensitivity to UVR in temporary pools /". Diss., 2004. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3127519.
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Shurin, Jonathan Bane. "Local and regional influences on the structure of freshwater zooplankton communities /". 2000. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:9978074.
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