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1
Menden-Deuer, Susanne. "Linking individual foraging strategies with ecological dynamics : quantifying zooplankton movements in heterogeneous resource distributions /". Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/11012.
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Martin, Traykovski Linda V. (Linda Victoria) 1966. "Acoustic classification of zooplankton". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/49620.
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Louw, Liezel. "The zooplankton of Mngazana estuary". Thesis, Nelson Mandela Metropolitan University, 2007. http://hdl.handle.net/10948/702.
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The zooplankton community of the main channel of the Mngazana estuary was investigated on six occasions over one year. Spatial and temporal variability in zooplankton abundance and distribution were sampled using two slightly modified WP2 plankton nets of 200 μm mesh and 57 cm mouth diameter. Nets were fitted with calibrated Kahlsico 005 WA 130 flow meters. A set of environmental variables were also measured at each site. The water column of the main channel of Mngazana estuary was stratified in summer but well mixed in winter. Temperature progressively increased from the lower stations to the upper reaches of the estuary. Maximum vertical temperature differences occurred in the middle estuarine reaches. Salinity progressively decreased from the lower reaches to the upper reaches, but was generally above 26 from Station 3 to Station 8. Only during November 2005, were salinity readings low due to heavy rains. Summer salinity values were always lower than the winter salinity values as a result of summer rainfall. A total of 76 zooplankton taxa were identified. The estuarine copepods Acartia natalensis and Pseudodiaptomus hessei dominated the assemblage, with maximum abundances in the middle to upper reaches. Acartia natalensis reached high densities in winter (> 50 000 m-3) although lowest abundances were recorded when maximum rainfall was received (November 2005). Wooldridge (1977) and Deyzel (2004) recorded maximum densities during summer. Pseudodiaptomus hessei reached high densities (> 17 000 m-3) during the highest rainfall month. Previous studies indicated that this pioneer species is able to recover quickly after a flood and subsequently increase rapidly in numbers. The mysid, Mesopodopsis africana reached high densities (> 5 000 m-3) in the middle estuarine reaches during summer. Ichtyofauna, brachyura and anomura were important contributors to the merozooplankton component of the community. The maximum number of species was recorded during winter in the lower estuarine reaches, when vertical differences in salinities were minimal.
4
Hunt, Brian Peter Vere. "Mesozooplankton community structure in the vicinity of the Prince Edward Islands (Southern Ocean) 37⁰ 50'E, 46⁰ 45'S". Thesis, Rhodes University, 2000. http://eprints.ru.ac.za/11/.
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Mitra, Aditee. "Zooplankton growth dynamics : a modelling study". Thesis, Open University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434264.
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Cole, Matthew. "The impacts of microplastics on zooplankton". Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/15288.
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In recent years there has been growing environmental concern regarding ‘microplastics’: microscopic plastic granules, fibres and fragments, categorised as <1 or <5 mm diameter. Microplastics are manufactured to be of a microscopic size, or derive from the photo- and mechanical degradation and subsequent fragmentation of larger plastic litter. Microplastics debris has been identified in the water column and sediments of marine and freshwater ecosystems across the globe, although difficulties in sampling and isolating smaller particulates has resulted in the abundance of <333 µm microplastics being under-reported. Microplastics are bioavailable to a range of aquatic organisms, including fish, seabirds and benthic invertebrates, and can be trophically transferred. The consumption of plastic debris can result in gut blockages, heightened immune response and a loss of lipid reserves. The potential risk to food security, and thereby human health, has led regulators to call for better understanding of the fate and effects of microplastic debris on marine life. Here I tested the hypothesis that microplastics can be ingested by and may negatively impact upon zooplankton. Zooplankton encompass a range of aquatic animals that form a key trophic link between primary producers and the rest of the marine food web. I used a suite of feeding experiments, bio-imaging techniques and ecotoxicological studies to explore the interactions and impacts of polystyrene microplastics on marine zooplankton. My results demonstrate that a range of filter-feeding zooplankton taxa, including copepods and bivalve and decapod larvae, have the capacity to ingest microplastics. Microplastics significantly reduced algal feeding in the copepods Centropages typicus and Calanus helgolandicus. With prolonged microplastic exposure C. helgolandicus produced smaller eggs with reduced hatching success, and had reduced survival owing to declining energetic reserves. Microplastics egested by copepods significantly altered the properties and sinking rates of faecal pellets, with potential repercussions for marine nutrient flux. This investigative work highlights that microplastics pose a significant risk to the health of animals at the base of the marine food web.
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Simoncelli, Stefano. "Hydrodynamics of migrating zooplankton in lakes". Thesis, University of Bath, 2018. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.761048.
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Zooplankton diel vertical migration (DVM) plays a pivotal role in controlling trophic interactions and nutrient transport in lakes and oceans. Understanding behaviours and responses of diel migrators is therefore essential to knowledge of physical processes and ecosystem functioning. This thesis investigated zooplankton hydrodynamics during the DVM in freshwater bodies through two different research topics. The first research explored the potential of swimming zooplankton hydrodynamics in affecting lake turbulent and biological processes. Past research suggests that zooplankton may be able to inject turbulent kinetic energy (TKE) in the water column when organisms swim. This process, referred to as biomixing, may increase vertical mixing in lakes. Since no field studies exist about biomixing by small zooplankton, turbulence and mixing were sampled in a lake during the dusk DVM of Daphnia. Results indicate that swimming Daphnia did not intensify dissipation rates of TKE and vertical fluxes. This suggests that small zooplankton cannot affect lake mixing even when organisms collectively swim. The second research examined how changes in ecosystem conditions affect zooplankton displacement velocity (DV) during the DVM of Daphnia. Currently, it is not known which environmental factors are key in driving this velocity. DV was measured in the field during the sunset migration (upwards DV) and sunrise migration (downwards DV) along with temperature, relative change in light intensity, chlorophyll-a and zooplankton concentration, as possible velocity drivers. Results show that upwards velocities were strongly correlated with the water temperature in the migrating layer, suggesting that temperature can control swimming activity, metabolic rates and escape reactions from predators. Downwards velocities were instead constant. Modelling this velocity as a sinking rate indicates that buoyancy and gravity are the governing parameters. The model also suggests that zooplankton favour passive sinking over active swimming to preserve energy and generate hydrodynamic disturbances not detectable by predators.
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Hobbs, Laura J. "Winter vertical migration of Arctic zooplankton". Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231440.
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In recent years, evidence has been found of Diel Vertical Migration (DVM) in zooplankton during the Polar Night in the Arctic Ocean. However, the drivers of this behaviour during an apparent lack of illumination and food are poorly understood, as is its spatial extent across the Arctic Ocean. A novel dataset comprising 58 deployments of moored Acoustic Doppler Current Profilers is used in this study to observe the vertical migratory behaviour of zooplankton on a pan-Arctic scale. Methods of circadian rhythm analysis are applied to detect synchronous activity. South of 75°N, DVM continues throughout winter (albeit with reduced vertical amplitude when compared to other times of the year). DVM is seen to cease for a short period of time (up to 50 days) at latitudes between 75° and 82°N. The duration for which DVM ceases is controlled primarily by latitude (and therefore the altitude of the sun), but is modified by sea-ice presence and other environmental parameters. A DVM pattern is not seen at 90°N at any time of the year, but ~365 day periodicity is detected in the surface backscatter levels at this latitude. During the Polar Night, the moon controls the vertical positioning of zooplankton across the Arctic. Aggregations at depth coincide with an avoidance of the surface for several (< 6) days over the full moon. The deepest aggregation is seen at 110 m, indicating a depth limit of moonlight perception. A new type of migratory behaviour is described: Lunar Vertical Migration (LVM) which exists as LVM-day (24.8 hour periodicity) and LVM-month (29.5 day periodicity) on a pan-Arctic scale. The strongest LVM-day is seen at 50 m depth. Sea-ice and cloud are found to modify both of these lunar responses. The results presented by this thesis show continuous activity throughout winter, and challenge assumptions of a quiescent Polar Night.
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Huliselan, Niette Vuca. "The temporal dynamics of three contrasting zooplankton communities with special reference to the role of zooplankton predators". Thesis, University of Newcastle Upon Tyne, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283689.
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Bernard, Kim Sarah. "Mesozooplankton community structure and grazing impact in the Polar Frontal Zone of the Southern Ocean". Connect to this title online, 2002. http://eprints.ru.ac.za/237/.
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Traiani, Stari. "Seasonal stability in time series of zooplankton". Thesis, University of Strathclyde, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544004.
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Merrix, Faye L. "Zooplankton in the newly formed Cardiff Bay". Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/54932/.
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1. Zooplankton are key organisms in the transfer of energy between trophic levels in standing waters. They have been used as model organisms in studies of competition, dispersal, predator-prey interactions and in the development of general ecological theory. However, studies of zooplankton in natural lakes have been far more numerous than those in artificial water bodies. 2. Available literature suggests that several areas of zooplankton community ecology have been relatively neglected in artificial lakes. These include i) direct comparisons between zooplankton assemblages in artificial and natural lakes, despite their differences in age ii) hydrological and morphological factors that could potentially cause variations within and between lakes iii) the effects of lake management on seasonal zooplankton dynamics and zooplankton distribution iv) over-wintering populations v) zooplankton functional traits, and trait character in relation to possible environmental selection. Zooplankton case studies in lowland, artificial, urban lakes are surprisingly rare given that such lakes are now often developed for amenity, recreation, conservation and flood storage, in addition to their role in water supply. 3. In this thesis, a series of hypotheses were developed in order to address the above gaps in knowledge and tested in Cardiff Bay, a recently formed and highly managed urban freshwater lake in South Wales (UK). Specific questions addressed were: 1) Globally, do artificial water bodies support different zooplankton assemblages from those in natural lakes 2) Does the zooplankton community of Cardiff Bay vary in ways predicted by ecological theory, and particularly as predicted by the Plankton Ecology Group (PEG) qualitative model of plankton succession 3) In Cardiff Bay, is there a persisting community of interacting zooplankton species even over less productive periods of the year 4) Do spatial and temporal dynamics in the zooplankton community of Cardiff Bay reflect local water quality 5) Do management practices in Cardiff Bay influence the temporal and spatial dynamics of zooplankton 6) Do the traits of zooplankton species in Cardiff Bay vary spatio-temporally in ways that might reflect environmental variation?
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Puls, Amy L. "Transport of zooplankton in South Slough, Oregon". Thesis, Thesis (M.S.)--University of Oregon, 2002, 2002. http://hdl.handle.net/1794/10057.
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Overman, Corina Christina Mae. "Modeling Vertical Migration of Cyanobacteria and Zooplankton". PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/5178.
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Cyanobacteria, also known as blue-green algae, often cause harmful algal blooms and release toxic substances that can harm humans and other animals. Accurately modeling these phytoplankton is a step towards predicting, preventing, and controlling such blooms. Cyanobacteria and zooplankton species are known to migrate vertically in the water column on a daily cycle. Capturing this behavior is one aspect of correctly modeling their dynamics. Here, several models of cyanobacteria vertical movement were tested in proof-of-concept models before being applied to data from field studies. These models included both continuum and particle-tracking frameworks. Four continuum-framework models of cyanobacteria vertical migration were chosen to add to the numerical hydrodynamic, water-quality model CE-QUAL-W2. These were tested using a model of Dexter Reservoir (Oregon), where they predicted vertical migratory movement seen in cyanobacteria. Models of zooplankton migration were also tested in proof-of-concept models as a steppingstone towards future incorporation into CE-QUAL-W2. Preliminary models of cyanobacteria and zooplankton vertical migration using a particle-tracking framework also provided information to be used in future model developments that will incorporate vertical migration of plankton into the particle-tracking module of CE-QUAL-W2.
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García, Pámanes Jorge. "Variacion dia-dia de la tasa de pastoreo zooplanctonico frente a Baja California, Mexico". Ensenada, B.C. : Centro de Investigación Científica y Educación Superior de Ensenada, Division de Oceanologia, Departamento de Ecologia, 1989. http://catalog.hathitrust.org/api/volumes/oclc/27757414.html.
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Jenkins, David G. "Structure and function of zooplankton colonization in twelve new experimental ponds /". This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-08252008-162217/.
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DuRant, Edward A. "Taxonomic and experimental investigation of secondary production in and near Cape Fear River plume waters". View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-1/rp/durante/edwarddurant.pdf.
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Graham, Sylvia Lynne. "Growth and grazing of microzooplankton in response to the harmful alga Heterosigma akashiwo in prey mixtures /". Online version, 2008. http://content.wwu.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=305&CISOBOX=1&REC=8.
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True, Aaron Conway. "Patchiness: zooplankton behavior in finescale vertical shear layers". Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42925.
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Regions containing gradients of vertical flow are often associated with sharp changes in hydrographic and biochemical water properties in coastal marine ecosystems. Often these are sites of dense plankton aggregations of critical ecological importance. In this study, a recirculating flume apparatus with a laminar, planar free jet (the Bickley jet) was used to create finescale gradients of fluid velocity (shear) in both upwelling and downwelling configurations for zooplankton behavioral assays. Particle image velocimetry (PIV) was used to fully resolve the velocity fields allowing us to fine-tune experimental parameters to match fluid mechanical conditions commonly measured in the field. Zooplankton behavioral assays with two tropical calanoid copepods, Acartia negligens and Clausocalanus furcatus, an estuarine mysid, Neomysis americana, and the larvae of an estuarine mud crab, Panopeus herbstii, were conducted in control (stagnant), upwelling, and downwelling flow configurations. Statistical analyses (ANOVA) of individual zooplankton trajectories revealed the potential for individual behavioral responses to persistent finescale vertical shear layers to produce population scale aggregations, which is proposed here as a mechanism of patchiness in coastal marine ecosystems. Results from behavioral analyses reveal species-specific threshold shear strain rates that trigger individual behavioral responses. Furthermore, results show statistically significant changes in behavior (relative swimming speed, turn frequency, heading) for all species tested in response to a coherent shear structure in the form of finescale upwelling and downwelling jets. The results show that changes in individual behavior can increase Proportional Residence Time (PRT = percent time spent in the jet structure). On a population scale, the increase in PRT can lead to dense aggregations around persistent flow features, which is consistent with numerous field studies. These dense, patchy aggregations of zooplankton have profound trickle-up ecological consequences in coastal marine ecosystems.
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Koenig, Brenda Grace. "Latitudinal patterns of polychlorinated biphenyls (PCBs) in zooplankton". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22914.pdf.
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Peijnenburg, Katja Theodora Catharina Adriana. "Structure at open sea genetics of zooplankton populations /". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2005. http://dare.uva.nl/document/89042.
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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.
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Dean, Hudson A. "Zooplankton spatial and seasonal distribution in Brooklands Lagoon". Thesis, University of Canterbury. Zoology, 1988. http://hdl.handle.net/10092/7069.
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The temporal and spatial distribution of zooplankton within Brooklands Lagoon was recorded at 3 sites representing a range of salinities and hydrographic conditions. Plankton tows were made monthly for one year to estimate seasonal abundance and distribution of zooplankton species. Diel distribution patterns were investigated in February by sampling at 3-hour intervals for a 30-hour period.
The 48 taxa identified within Brooklands Lagoon represent a depauperate fauna compared with the nearby Avon-Heathcote estuary and the Kaikoura coastal waters. Brooklands Lagoon had approximately one tenth of the zooplankton biomass found in the Avon-Heathcote estuary. Results of ordination analysis showed a succession of dominant groups: Acartia sp., Microcyclops sp., Camptocercus sp. and Miscegenus heretunga in the summer, followed by barnacle and copepod nauplii during the winter. Changes in zooplankton abundance and biomass were influenced more by river flow and the degree of seawater mixing, than season, chlorophyll a concentration or temperature.
Daily zooplankton abundance patterns were strongly influenced by darkness, resulting from the combined effect of turbidity and diel period. Zooplankton were also abundant during the early morning while chlorophyll a concentrations were increasing. The meroplankton showed high biomass and abundances during daytime high tides.
Gut analysis of larval mullet, Mugil cephalus showed a diet of cyclopoid copepods, ostracods and oligochaetes. The flatfish larvae, Rhombosolea plebia, revealed a high dependance on zooplankton, eating almost exclusively Miscegenus heretunga. This harpacticoid copepod had a temperature/salinity tolerance between 1.7->40ppt. salinity and <5-26°C over 24hours. This tolerance range is wider than the temperature and salinity ranges recorded in the lagoon.
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Abdul-Hussein, M. M. "Zooplankton and phytoplankton interactions in an eutrophic reservoir". Thesis, University of Essex, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355111.
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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.
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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.
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Kalytytė, Daiva. "Phytoplankton and zooplankton community structure and change in characteristic mesotrophic lakes of Lithuania". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20101022_095233-10799.
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Studies of plankton community provide vital information in assessing the ecological status of lakes and their evolution. Phytoplankton is essential, and often the only primary producer of organic matter. Zooplankton takes an important place in the pelagic food chain because of the link between the primary producers and higher trophic levels. The most valuable are Lithuanian mesotrophic lakes. Depending on zooplankton communities, those lakes can be divided in 3 (characteristic) groups: lakes with glacial relict calanoids Limnocalanus macrurus, lakes with another calanoids Eurytemora lacustris and lakes without relict crustaceans. The information obtained after examination of several lakes from different groups, is useful for evaluating the status of Lithuanian mesotrophic lakes.
The aim of the present study was to identify defining characteristics of phytoplankton and zooplankton community structure and change in Lithuanian mesotrophic lakes, compare plankton communities and to assess change trends of Lithuanian mesotrophic lakes.
In this study complex analyses of phytoplankton and zooplankton structure were performing in mesotrophic lakes. Our data assess the current state of Lithuanian mesotrophic lakes and complement the information about phytoplankton and zooplankton in mesotrophic lakes. The obtained results are important for evaluation of the ecological status of the lakes and providing the environmental control tools to ensure good ecological status of the lakes. For... [to full text]Planktono bendrijos tyrimai teikia esminę informaciją vertinant ežerų ekologinę būklę ir jų raidos tendencijas, nes planktono dumbliai yra pagrindiniai, o dažnai ir vieninteliai pirminės organinės medžiagos producentai, o zooplanktonas yra grandis tarp pirminių producentų ir aukštesnių mitybos lygmenų pelaginėje mitybos grandinėje. Vertingiausi ekologiniu pažiūriu yra mezotrofiniai Lietuvos ežerai. Juos pagal zooplanktono bendrijas galima suskirstyti į 3 (charakteringas) grupes: ežerus, kuriuose gyvena irklakojis vėžiagyvis Limnocalanus macrurus, ežerus apgyvendintus kito relikto Eurytemora lacustris ir ežerus be ledynmečio reliktinių planktono vėžiagyvių. Informacija apie šių ežerų grupėse vykstančius procesus teikia galimybę vertinti Lietuvos mezotrofinių ežerų raidos tendencijas. Darbo tikslas – nustatyti charakteringų mezotrofinių Lietuvos ežerų planktono dumblių ir vėžiagyvių bendrijų struktūrą ir kaitą, palyginti ežerų grupių planktono bendrijas ir įvertinti Lietuvos mezotrofinių ežerų kitimo tendencijas. Darbe atlikti kompleksiniai mezotrofinių ežerų fitoplanktono ir zooplanktono struktūros tyrimai. Šie duomenys įvertina dabartinę Lietuvos mezotrofinių ežerų būklę ir jos raidos tendencijas, bei papildo informaciją apie mezotrofinių ežerų fitoplanktoną ir zooplanktoną. Pirmą kartą Lietuvoje atlikti dumblių ramybės stadijų aktyvacijos veiksnių tyrimai. Tirtuose ežeruose apibūdintos 32 anksčiau Lietuvoje neregistruotos dumblių ir melsvabakterių rūšys.
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Tarasova, Natal︠i︡a Anatolʹevna. "Ėkologi︠i︡a mezozooplankton ︠i︡ugo-vostoka baren︠t︡seva mor︠i︡a". Syktyvkar [Russia : Institut ėkologicheskikh problem Severa Uralʹskogo otdelenii︠a︡ RAN], 2003. http://catalog.hathitrust.org/api/volumes/oclc/58810619.html.
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Llinas, Leopoldo. "Distribution, Reproduction, and Transport of Zooplankton in the Western Arctic". Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/25.
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This dissertation focuses on the distribution, reproduction, and transport of zooplankton in the Chukchi and Beaufort seas and adjacent Canada Basin. Specifically, it analyzes 1) the species-specific distribution of copepod nauplii as it is forced by the surface layer mesoscale circulation and physical properties, 2) the reproduction of the dominant copepod Calanus glacialis in the western Arctic, and 3) the effects of eddy transport on the zooplankton community in the Chukchi and Beaufort seas and Canada Basin. To achieve this I adapted a molecular identification method to work with small crustaceans. The method was successfully used to generate a sequence database from adult copepods of species present in the region. Differences in the D1/D2 domains of the large subunit ribosomal were sufficient for the identification of all species present in the western Arctic with the exception of two sibling Calanus copepods which were discriminated using the mitochondrial cytochrome oxidase I gene. The application of this semi-robotic protocol to selected surface samples collected from the USCGC Healy in summer 2004 revealed that four copepod species dominated the naupliar community: Oithona similis, C. glacialis, Pseudocalanus minutus, and P. mimus. Each species had different abundance and distribution patterns related to their specific life cycles and environmental affinities. The molecular identification method was then applied to study the egg production rates of C. glacialis and differentiate it from C. marshallae. This work validated reported spatial and seasonal variations in egg production rates in C. glacialis and showed that an increase in primary production in summer 2004 compared to summer 2002 did not result in an increase in secondary production of this copepod. The last component of this study is the result of a unique sampling design to study shelf-basin interactions. The results provided evidence of on-shelf transport of basin organisms by a wind-induced upwelling event and of eddy-mediated advection of zooplankton from the surrounding shelves into the Arctic basin. Overall, this study integrated new molecular tools and unusual sampling opportunities to advance our understanding of the role zooplankton in this Arctic ecosystem.
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Henderson, Anna Maria. "An investigation into aspects of the ecology of aquatic microfauna of two man-made lakes in North East England". Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268374.
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Guyard, Philippe Henri. "Effects of oceanographic factors on the mesozooplanktonic communities of the East Solent and outer approaches". Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313323.
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32
Edwards, Andrew Michael. "A rational dynamical-systems approach to plankton population modelling". Thesis, University of Leeds, 1997. http://etheses.whiterose.ac.uk/21072/.
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Understanding the dynamics of plankton populations is of major importance since plankton form the basis of marine food webs throughout the world's oceans and play a significant role in the global carbon cycle. In this thesis we examine the dynamical behaviour of plankton models, exploring sensitivities to the number of variables explicitly modelled, to the functional forms used to describe interactions, and to the parameter values chosen. The practical difficulties involved in data collection lead to uncertainties in each of these aspects of model formulation. The first model we investigate consists of three coupled ordinary differential equations, which measure changes in the concentrations of nutrient, phytoplankton and zooplankton. Nutrient fuels the growth of the phytoplankton, which are in turn grazed by the zooplankton. The recycling of excretion adds feedback loops to the system. In contrast to a previous hypothesis, the three variables can undergo oscillations when a quadratic function for zooplankton mortality is used. The oscillations arise from Hopf bifurcations, which we track numerically as parameters are varied. The resulting bifurcation diagrams show that the oscillations persist over a wide region of parameter space, and illustrate to which parameters such behaviour is most sensitive. The oscillations have a period of about one month, in agreement with some observational data and with output of larger seven-component models. The model also exhibits fold bifurcations, three-way transcritical bifurcations and Bogdanov-Takens bifurcations, resulting in homo clinic connections and hysteresis. Under different ecological assumptions, zooplankton mortality is expressed by a linear function, rather than the quadratic one. Using the linear function does not greatly affect the nature of the Hopf bifurcations and oscillations, although it does eliminate the homoclinicity and hysteresis. We re-examine the influential paper by Steele and Henderson (1992), in which they considered the linear and quadratic mortality functions. We correct an anomalous normalisation, and then use our bifurcation diagrams to interpret their findings. A fourth variable, explicitly modelling detritus (non-living organic matter), is then added to our original system, giving four coupled ordinary differential equations. The dynamics of the new model are remarkably similar to those of the original model, as demonstrated by the persistence of the oscillations and the similarity of the bifurcation diagrams. A second four-component model is constructed, for which zooplankton can graze on detritus in addition to phytoplankton. The oscillatory behaviour is retained, but with a longer period. Finally, seasonal forcing is introduced to all of the models, demonstrating how our dynamical systems approach aids understanding of model behaviour and can assist with model formulation.
33
Severin-Edmaier, Gabriele Felicitas. "Effekte hormonell wirksamer Substanzen auf das Zooplankton aquatischer Modellökosysteme". [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960409238.
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34
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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35
Laferriere, Alison Mariah. "Distribution of zooplankton and detritus within Langmuir circulation cells /". Connect to online version of this title in UO's Scholars' Bank, 2007. http://hdl.handle.net/1794/6058.
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36
Davidson, Thomas Alexander. "Zooplankton ecology and palaeoecology of nutrient enriched shallow lakes". Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444372/.
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This study sought to determine the potential of sedimentary cladoceran assemblages for inferring changes in shallow lake ecological structure and function. The first stage of the study aimed to isolate and quantify the main structuring forces of the contemporary zooplankton community. Zooplankton populations were sampled from 39 mesotrophic to hyper-eutrophic shallow lakes (<3 m average depth) in the U.K. and Denmark. Additionally, a suite of environmental variables, including: fish, macrophytes, algal crop, nutrient concentrations and water transparency were analysed. A variety of numerical techniques including constrained ordination and logistic regression were employed to determine whole community and individual species response to the environmental variation within the data set. The sedimentary remains of zooplankton were then enumerated from the surface sediments of the 39 'training set' lakes. These data were compared with the contemporary counts. Despite differential preservation of sedimentary remains, the main factors structuring the assemblages were the same in both data sets, zooplanktivorous fish density (ZF) and submerged macrophyte abundance (MA). Furthermore, these factors displayed a similar degree of influence on both assemblages. A multivariate regression tree (MRT) was used to calibrate sedimentary cladoceran assemblage response to ZF and MA. The resultant model places a site in one of five groups based on cladoceran assemblage and corresponding to a range of values of ZF and MA. These groups represent distinct forms of ecosystem structure and function varying from sites with clear water, abundant macrophytes and low ZF to turbid, phytoplankton dominated systems with high ZF. Sedimentary cladoceran assemblages from dated cores for two sites, Felbrigg Lake (Norfolk, England) and Kenfig Pool (Glamorgan, Wales) were analysed. The cladoceran inferred ZF and MA indicated that both sites have undergone dramatic changes in ZF and MA. Comparison with plant macrofossil data and historical records at both sites indicated the veracity of the model.
37
Wood, S. N. "Estimation of mortality rates in stage-structured zooplankton populations". Thesis, University of Strathclyde, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278525.
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38
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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39
Gordon, Christopher. "Studies on the crustacean zooplankton of the Thames Estuary". Thesis, King's College London (University of London), 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480849.
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40
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.
41
Laferriere, Alison Mariah 1976. "Distribution of Zooplankton and Detritus within Langmuir Circulation Cells". Thesis, University of Oregon, 2007. http://hdl.handle.net/1794/6058.
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xi, 70 p. : ill., maps. A print copy of this title is available from the UO Libraries under the call number: SCIENCE GC228.5 L34 2007Langmuir circulation cells are wind generated surface currents, which take the form of alternating clockwise and counter clockwise rotating helical cells. Models suggest that organisms and particles may be retained in the convergence and divergence zones depending on the relative settling and swimming velocity versus circulation velocity. Surface water in convergence and divergence zones of Langmuir circulations were sampled with plankton nets and zooplankton and fecal pellets were enumerated. Copepods did not differ significantly between zones. Balanus glandula cyprids, competent Polydora spp., and an unidentified late stage veliger were often significantly concentrated in convergence zones. These results suggest that late stage larvae may be exploiting Langmuir circulation as a transport mechanism to travel shoreward for settlement. Fecal pellets were more concentrated in divergence zones on four out of six sample days. On the two days when pellets were more concentrated in convergence zones the swell was larger.
Adviser: Alan Shanks
42
Bickel, Samantha L. "Anthropogenic Causes of Copepod Mortality and Bacterial Decomposition of Copepod Carcasses". W&M ScholarWorks, 2009. http://www.vims.edu/library/Theses/Bickel09.pdf.
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Gustavsson, Maria. "Kalkningseffekter på plankton : ett mesokosmexperiment i den kalkrika sjön Tåkern". Thesis, Linköpings universitet, Biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-130869.
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One of today's major environmental issues is algal blooms linked to eutrophication of lakes and oceans. That is a result of anthropogenic influence with nutrient loads (including phosphorus) from agriculture and industry, which benefits primary production (phytoplankton). Studies have shown that phosphorus availability in the water column can be limited by liming, therefore could be a way to counteract eutrophication. This was tested in the agriculturally surrounded lake Tåkern in southern Sweden, which in its present state is an internationally important bird lake and therefore in several respects would be affected by eutrophication. The purpose of this study was to investigate whether liming would be a good solution to solve any future eutrophication problems in Lake Tåkern. Liming experiments were performed in mesocosms during April 2015 with a mixture of limestone and slaked lime. Quantity and diversity of plankton and water chemical variables were measured before and after liming. Moreover, samples of phytoplankton from a similar experiment conducted in July 2014 were analyzed. Liming did not show any effect on neither phyto- nor zooplankton when performed in spring of 2015. During summer of 2014, there was an increase in number of phytoplankton (ml-1 ) and chlorophyll in controls while the study showed constant levels in treated mesocosms. For zooplankton there was no significant effects of liming on neither quantity nor diversity. Results of this study suggest that liming is not the most appropriate method to resolve eutrophication in Lake Tåkern.
44
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.
45
Maise, Susanne. "Natural variability of zooplankton and phytoplankton in outdoor aquatic microcosms". [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964809427.
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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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47
Smith, Colin Douglas. "Aspects of the ecology of crustacean zooplankton in Rutland Water". Thesis, University of Leicester, 1988. http://hdl.handle.net/2381/34237.
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Rutland Water is a large (1260 ha) eutrophic pumped- storage reservoir in the lowland east midlands of England, impounded in 1975. Artificial mixing during the summer is continuous but weak, with a polymictic regime controlled by wind mixing. The crustacean zooplankton was studied during 1984 and 1985. Daphnia hyalina forma lacustrls Sars was the dominant limnetic cladoceran, with Daphnia pulex (De Geer), Bosmlna longlrostrls (O.F. Muller) and Leptodora klndtl (Focke) also present. Six limnetic copepods were present: Eudlaptomus gracilis (Sars), Eurytemora velox (Li 11jeborg), Cyclops abyssorum Sars, Cyclops vlclnus Uljanin, Acanthocyclops robustus (Sars) and Mesocyclops leuckartl (Claus). Cyclops vlclnus entered diapause as copepodite IV in May, emerging during November-March.' Reproduction was more synchronous than expected from the period of emergence and could not be explained in terms of temperature-dependent development times alone. Food availability may have limited reproduction until the spring diatom peak. The mean species richness of copepods, at 5*2, was unusually high. Species composition had changed since impoundment and this richness might represent a transition from founder species to successful immigrants. Possible mechanisms of coexistence for the calanoid species and for Cyclops species were discussed: exclusion may not occur. Features which distinguish copepodite larval instars are well known. Determination of the calanoid species was possible in all instars but the cyclopoid species were less distinct. Cyclopoids in the fifth copepodite stage showed many adult characters but earlier instars of different species did not differ qualitatively with respect to the features which were examined. The vertical distribution of Crustacea was similar to that typical of stratifying lakes, with highest densities of all groups in the upper part of the column. Agreement was found with the buoyancy/current model of large-scale horizontal patchiness. It was suggested that the effects on horizontal patchiness of *'conveyor-belt" currents should be greater in the mixed column due to a more complete coincidence of zooplankton abundance maxima and the leeward wind-driven flow.
48
Morneau, Jean Philippe. "Trace metal analysis of marine zooplankton from Conception Bay, Newfoundland". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23164.pdf.
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Yazgan, Tavsanoglu Ulku Nihan. "Zooplankton Adaptation Strategies Against Fish Predation In Turkish Shallow Lakes". Phd thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615354/index.pdf.
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In this study, the factors influencing zooplankton community structure in Turkish
shallow lakes were elucidated with four main approaches: (i) space-for-time
substitution for shallow lakes using snap-shot sampling in 31 lakes along a latitudinal
gradient(ii) in-situ mesocosm experiments in eleven lakes along a latitudinal gradient using three sets of artificial plants systems
(iii)&lsquo
Habitat Choice&rsquo
laboratory experiments mimicking a &lsquo
shallow littoral&rsquo
zone with plants and a &lsquo
deeper pelagic&rsquo
zone with sediments testing the response of Daphnia magna to predation cues
and (iv) long-term monitoring data (1997-2011) from two interconnected lakes. Snap-shot and long-term monitoring showed that eutrophication has a strong influence on the zooplankton community via increased fish predation, nutrient loading and salinization. Here too the zooplankton community shifted towards a smaller sized profile, especially in lakes located at lower latitudes. Moreover, The laboratory and in-situ mesocosm experiments revealed that under predation risk Daphnia preferred to hide near sediment instead of using submerged plants as a refuge. Accordingly, in-situ mesocosm experiments revealed a predation pressure induced size structure shift towards small-medium sized zooplankton and calanoid copepods. The long-term monitored lakes experienced (i) drought-induced water level drop, leading to increased salinity and eutrophication, and consequent anoxic conditions and fish kill
as well as (ii) biomanipulation in the downstream. Both conditions resulted in major reduction in the top-down control of fish and ultimate predomination by large sized Daphnia spp. Nevertheless, the excessive exploitation of lakes and ongoing warming entail Turkish shallow lakes to become more eutrophic, making this study indicative for the Mediterranean region.
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Humphrey, Donald B. "Characterizing ballast water as a vector for nonindigenous zooplankton transport". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2391.
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The global movement of aquatic non-indigenous species can have severe ecological, environmental and economic impacts emphasizing the need to identify potential invaders and transport pathways. Initial transport is arguably the most important stage of the invasion process owing to its role in selectively determining potential invasion candidates. This study characterizes a well defined human-mediated dispersal mechanism, ballast water transport, as a vector for the introduction of non-indigenous zooplankton. Ballast water exchange in the open ocean is the most widely adopted practice for reducing the threat of aquatic invasions and is mandatory for most foreign vessels intending to release ballast in Canadian waters. Ships entering Canadian ports are categorized into the following three shipping classes based on current regulations: overseas vessels carrying exchanged ballast water, intra-coastal vessels carrying exchanged ballast water or intra-coastal vessels carrying un-exchanged ballast water. This study characterizes zooplankton communities associated with each of these shipping classes sampled from ports on Canada’s Pacific coast, Atlantic coast and the Great Lakes Basin. Ballast water samples were collected and analyzed from 77 vessels between 2006 - 2007. The ballast water environment was found to be diverse, with over 193 zooplankton taxa, 71 of which were non-indigenous to their receiving environments. Intracoastal vessels containing un-exchanged coastal water transported the greatest density of non-indigenous zooplankton into Canadian ports. Total zooplankton density was found to be negatively correlated with ballast water age The absence of mandatory ballast water exchange and the younger ballast water age of coastal un-exchanged vessels is likely responsible for the higher density of non-indigenous zooplankton in intracoastal un-exchanged vessels. Propagule pressure, invasion history and environmental suitability are all useful in evaluating invasion potential and all suggest that intracoastal un-exchanged vessels pose the greatest invasion threat to Canadian aquatic ecosystems. In conclusion, although the risk of primary introductions from overseas ports may have been reduced through open-ocean exchange of ballast water, secondary introductions from previously invaded ports in North America may be the primary threat to Canadian aquatic ecosystems via this transport vector.