Global ETD Search
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Showing 1 to 20 of 356 for “"Zooplankton"”.
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Acoustic classification of zooplankton
Work on the forward problem in zooplankton bioacoustics has resulted in the identification of three categories of acoustic scatterers: elastic-shelled (e.g. pteropods), fluid-like (e.g. euphausiids), and gas-bearing (e.g. siphonophores). The relationship between backscattered energy and animal …
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Zooplankton in Flowing Waters
The zooplankton community structure within a river is governed by a variety of physical, chemical, and environmental features. The current study assessed the role of flow in characterizing the microcrustacean zooplankton community of the Missouri River. I also designed an artificial flow chamber …
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Acoustic classification of zooplankton
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 1998.
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Winter vertical migration of Arctic zooplankton
… 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 …
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Zooplankton of the Cape Peninsula upwelling region
The vertical and horizontal distribution of meso-zooplankton in the vicinity of an extremely active upwelling site in the southern Benguela Current is described. Zooplankton samples collected in oceanic, newly-upwelled and mature upwelled water showed that temperature, chlorophyll and time of day …
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Acoustic target classification of zooplankton using machine learning
Acoustic target classification of zooplankton is challenging due to their small size, weak target strengths (TS), and tendency to form dense, mixed-species aggregations, which limits the effectiveness of conventional methods based on volume backscatter. Broadband echosounders measure backscatter …
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Factors influencing zooplankton communities in small freshwater lochs
The work contained here examined the zooplankton of small freshwater lochs in Highland Scotland. Investigations focused on zooplankton community composition based upon environmental factors and the viability of these lochs as ‘canaries’ of climate change. Sampling occurred at 30 sites which were …
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Keanekaragaman zooplankton di Perairan Pantai Lekok Kabupaten Pasuruan
INDONESIA: Keanekaragaman Zooplankton Di Perairan Pantai Lekok Kabupaten Pasuruan merupakan gambaran kelimpahan zooplankton yang hidup di perairan. Zooplankton merupakan jenis hewan yang menjadi konsumen primer. Kelimpahan zooplankton sangat di pengaruhi keberadaan fitoplankton sebagai cadangan …
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Intake flow fields for a zooplankton pump sampling system
… quantified. This data is applied to a model of zooplankton sampler performance, to predict the fraction of the sampled fluid from which no animals will escape under conditions similar to those of the tests. Flume flow speeds (≈5 cm/s) and intake pumping rate (≈33 gal/min) are scaled by a factor …
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Orientation dependence of the acoustic backscatter for elongated zooplankton
The width of the main lobe of the acoustic backscatter directivity pattern of decapod shrimp (Palaemonetes vulgaris) is examined versus acoustic frequency. Using the distorted wave Born approximation (DWBA) and the geometry of a prolate spheroid, an analytic formula for the backscatter cross …
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Crustacea Zooplankton Communities in Icelandic Lakes Comparison Over Time
This study examines freshwater Crustacea zooplankton communities in 19 Icelandic lakes, focusing on Copepoda and Cladocera. Zooplankton form a key trophic link in freshwater ecosystems, grazing on phytoplankton and serving as prey for higher trophic levels. Monitoring biodiversity in Arctic and …
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Zooplankton phytoplankton interactions in the San Joaquin River, Ca
<p>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 …
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Zooplankton and Ichthyoplankton in a Power Plant Cooling Reservoir
… distribution, and entrainment mortality of zooplankton and ichthyoplankton were studied in the Big Stone Power Plant cooling reservoir, South Dakota, from January 1979 to April 1980. Mean annual density and biomass of zooplankton for 1979 were 15.8 organisms/liter and 384.7 ug/liter …
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Ecological and evolutionary effects of dispersal on freshwater zooplankton
… and gene flow among populations. Freshwater zooplankton are aquatic crustaceans that typically develop resting stages as part of their life cycle. Their dormant propagules allow organisms to disperse both temporally and among habitats. Additionally, because a number of species are cyclically …
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Environmental Instability and the Structure of Temporary Pond Zooplankton Communities
Chapter I. Ideas relating environmental instability and community diversity are reviewed. The distinction is made between evolutionary mechanisms, which require very long periods of time to operate, and ecological mechanisms, which operate over shorter spans of time. As part of the discussion of …
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Phytoplankton growth and zooplankton grazing in the southern Benguela current
The development and production of several phytoplankton communities and the consumption of these communities plankton were investigated in newly by herbivorous mesozooupwelled waters of the southern Benguela Current by means of an electronic counting and sizing technique (Coulter counter). A …
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The role of zooplankton in cyanobacteria bloom development in Australian reservoirs
… because much of the current understanding about zooplankton-cyanobacteria interactions comes from temperate systems dominated by large-bodied cladocerans. Given that warmer subtropical systems are dominated by copepods and smaller-bodied individuals, it is likely that interactions between …
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Endobenthic Ecosystem Engineering: influence of sandprawns (Callichirus kraussi) on zooplankton assemblages
… indirect effects on filter feeders such as zooplankton assemblages. To date, there has been no known research addressing questions on density of sandprawns and associated effects on zooplankton assemblages. This study therefore aimed to address this knowledge gap and quantify the influence …
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