Download or read book Distribution Patchiness and Behavior of Antarctic Zooplankton Assessed Using Multi frequency Acoustic Techniques written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Submitted to the MIT Department of Biology and the WHOI Biology Department in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2006.
Download or read book Distribution Patchiness and Behavior of Antarctic Zooplankton Assessed Using Multi frequency Acoustic Techniques written by Gareth L. Lawson and published by . This book was released on 2006 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: The physical and biological forces that drive zooplankton distribution and patchiness in an antarctic continental shelf region were examined, with particular emphasis on the Antarctic krill, Euphausia superba. This was accomplished by the application of acoustic, video, and environmental sensors during surveys of the region in and around Marguerite Bay, west of the Antarctic Peninsula, in the falls and winters of 2001 and 2002. An important component of the research involved the development and verification of methods for extracting estimates of ecologically-meaningful quantities from measurements of scattered sound. The distribution of acoustic volume backscattering at the single frequency of 120 kHz was first examined as an index of the overall biomass of zooplankton. Distinct spatial and seasonal patterns were observed that coincided with advective features. Improved parameterization was then achieved for a theoretical model of Antarctic krill target strength, the quantity necessary in scaling measurements of scattered sound to estimates of abundance, through direct measurement of all necessary model parameters for krill sampled in the study region and survey period.
Download or read book The Journal of the Acoustical Society of America written by Acoustical Society of America and published by . This book was released on 2007 with total page 1306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sustained Glider Observations of Acoustic Scattering Suggest Zooplankton Patches are Driven by Vertical Migration and Surface Advective Features in Palmer Canyon Antarctica written by Cordielyn S. Goodrich and published by . This book was released on 2018 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antarctic zooplankton and micronekton link the highly productive waters of the Southern Ocean to upper trophic levels. The distribution of zooplankton and micronekton is highly patchy both vertically and horizontally, suggesting that both behavior and oceanographic advection are important for understanding their distributions. A Slocum glider was deployed with an acoustic Doppler current profiler within a surface current field measured by HF-Radar in Palmer Canyon, Antarctica, during austral summer. I used this data to investigate the relative importance of surface currents and vertical migration behavior on the presence of zooplankton and micronekton in the mixed layer. I show that zooplankton and micronekton are more likely to be found shallower than the mixed layer during night-time hours, indicating diel vertical migration is a driver of their vertical distribution. I also found both Eulerian and Lagrangian characterizations of surface physical features to be important in predicting the presence of zooplankton and micronekton shallower than the mixed layer. While I found that both diel vertical migration (DVM) and surface currents were significant predictors of zooplankton and micronekton presence above the mixed layer, the strongest predictor of zooplankton and micronekton presence were surface currents represented as repelling Lagrangian Coherent Structures (LCS). This indicates that in this region during summer, horizontal advection and behavior plays a critical component in structuring zooplankton and micronekton distributions.
Download or read book Estimating Gulf of Maine Zooplankton Distributions Using Multiple Frequency Acoustic Video and Environmental Data written by Joseph David Warren and published by . This book was released on 2001 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis develops methods useful for estimating zooplankton distributions in the field by combining acoustic scattering models and an integrated set of field data. The accuracy of existing scattering models for fluid-like and elastic-shelled animals is determined by analysis of scattering data from individual animals in a laboratory tank. Results indicate that simple two-ray scattering models are accurate and allow predictions of size or orientation of an animal to be made for certain animal orientations. A scattering model for gas-bearing zooplankton is compared with in situ multiple frequency acoustic measurements from siphonophores. Estimates of the numerical density of these animals are made using echo integration data from a scientific echo-sounder. Multiple frequency acoustic scattering data from a survey of an internal wave are analyzed to determine the contributions from biological and physical sources. Net tow data provide information about biological scatterers while temperature and salinity profiles are used with a theoretical scattering model to predict contributions from physical sources. Results indicate that scattering from physical sources is comparable to that from biological sources in certain regions and that scattering spectra may be used to distinguish these sources. Improved estimates of biomass from acoustic scattering data were made by accounting for the scattering contributions from physical sources. This is the first work to quantify the scattering contributions from biological and physical sources of scattering in a field study.
Download or read book Oceanic Abstracts written by and published by . This book was released on 1996-10 with total page 1002 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observations of Zooplankton Patchiness Using a High Frequency Sonar and a Multiple Sample Plankton Net written by Paul Richard Greenblatt and published by . This book was released on 1980 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The CCAMLR 2000 Survey written by Jon L. Watkins and published by . This book was released on 2004 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Fisheries and Aquatic Sciences written by and published by . This book was released on 1993 with total page 932 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ICES Zooplankton Methodology Manual written by Roger Harris and published by Elsevier. This book was released on 2000-02-14 with total page 707 pages. Available in PDF, EPUB and Kindle. Book excerpt: The term "zooplankton" describes the community of floating, often microscopic, animals that inhabit aquatic environments. Being near the base of the food chain, they serve as food for larger animals, such as fish. The ICES (International Council for the Exploration of the Sea) Zooplankton Methodology Manual provides comprehensive coverage of modern techniques in zooplankton ecology written by a group of international experts. Chapters include sampling, acoustic and optical methods, estimation of feeding, growth, reproduction and metabolism, and up-to-date treatment of population genetics and modeling. This book will be a key reference work for marine scientists throughout the world. - Sampling and experimental design - Collecting zooplankton - Techniques for assessing biomass and abundance - Protozooplankton enumeration and biomass estimation - New optical and acoustic techniques for estimating zooplankton biomass and abundance - Methods for measuring zooplankton feeding, growth, reproduction and metabolism - Population genetic analysis of zooplankton - Modelling zooplankton dynamics This unique and comprehensive reference work will be essential reading for marine and freshwater research scientists and graduates entering the field.
Download or read book 2002 Ocean Sciences Meeting written by and published by . This book was released on 2002 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biology and Ecology of Antarctic Krill written by Volker Siegel and published by Springer. This book was released on 2016-08-03 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a unique insight into the current knowledge of krill population dynamics including distribution, biomass, production, recruitment, growth and mortality rates. Detailed analysis is provided on food and feeding, reproduction and krill behaviour. The volume provides an overview on the aspects of natural challenges to the species, which involve predation, parasites and the commercial exploitation of the resource and its management. A chapter on genetics shows the results of population subdivision and summarizes recent work on sequencing transcriptomes for studying gene function as part of the physiology of live krill. The focus of Chapter 4 is on physiological functions such as biochemical composition, metabolic activity and growth change with ontogeny and season; and will demonstrate which environmental factors are the main drivers for variability. Further discussed in this chapter are the bottle necks which occur in the annual life cycle of krill, and the mechanisms krill have adapted to cope with severe environmental condition.
Download or read book The Zoological Record written by and published by . This book was released on 1870 with total page 1480 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Stocks of Whales written by Neil Alison Mackintosh and published by . This book was released on 1965 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adaptive Sampling written by Steven K. Thompson and published by Wiley-Interscience. This book was released on 1996-06-07 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offering a viable solution to the long-standing problem of estimating the abundance of rare, clustered populations, adaptive sampling designs are rapidly gaining prominence in the natural and social sciences as well as in other fields with inherently difficult sampling situations. In marked contrast to conventional sampling designs, in which the entire sample of units to be observed is fixed prior to the survey, adaptive sampling strategies allow for increased sampling intensity depending upon observations made during the survey. For example, in a survey to assess the abundance of a rare animal species, neighboring sites may be added to the sample whenever the species is encountered during the survey. In an epidemiological survey of a contagious or genetically linked disease, sampling intensity may be increased whenever prevalence of the disease is encountered. Written by two acknowledged experts in this emerging field, this book offers researchers their first comprehensive introduction to adaptive sampling. An ideal reference for statisticians conducting research in survey designs and spatial statistics as well as researchers working in the environmental, ecological, public health, and biomedical sciences. Adaptive Sampling: Provides a comprehensive, fully integrated introduction to adaptive sampling theory and practice Describes recent research findings Introduces readers to a wide range of adaptive sampling strategies and techniques Includes numerous real-world examples from environmental pollution studies, surveys of rare animal and plant species, studies of contagious diseases, marketing surveys, mineral and fossil-fuel assessments, and more
Download or read book Marine Anthropogenic Litter written by Melanie Bergmann and published by Springer. This book was released on 2015-06-01 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes how man-made litter, primarily plastic, has spread into the remotest parts of the oceans and covers all aspects of this pollution problem from the impacts on wildlife and human health to socio-economic and political issues. Marine litter is a prime threat to marine wildlife, habitats and food webs worldwide. The book illustrates how advanced technologies from deep-sea research, microbiology and mathematic modelling as well as classic beach litter counts by volunteers contributed to the broad awareness of marine litter as a problem of global significance. The authors summarise more than five decades of marine litter research, which receives growing attention after the recent discovery of great oceanic garbage patches and the ubiquity of microscopic plastic particles in marine organisms and habitats. In 16 chapters, authors from all over the world have created a universal view on the diverse field of marine litter pollution, the biological impacts, dedicated research activities, and the various national and international legislative efforts to combat this environmental problem. They recommend future research directions necessary for a comprehensive understanding of this environmental issue and the development of efficient management strategies. This book addresses scientists, and it provides a solid knowledge base for policy makers, NGOs, and the broader public.
Download or read book The Norwegian Sea Ecosystem written by Hein Rune Skjoldal and published by Fagbokforlaget. This book was released on 2004 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: 'The Norwegian Sea Ecosystem' elucidates the interaction between the different ecological compartments of the area, with special emphasis on the most important pelagic fish stocks. It deals with mechanisms for ecosystem variability and discusses the challenge of an ecosystem approach to managing the area.
