Download or read book Relations Among Zooplankton Abundance Biomass Community Structure and Lake Trophic State in Selected Midwestern Waterbodies written by Timothy J. Canfield and published by . This book was released on 1988 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Oata Analysis and Synthesis (CINOAS) * at Purdue. University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna tional publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 33 (thesis year 1988) a total of 13,273 theses titles from 23 Canadian and 1 85 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work. While Volume 33 reports theses submitted in 1988, on occasion, certain univer sities do report theses submitted in previous years but not reported at the time.
Download or read book Fisheries Review written by and published by . This book was released on 1993 with total page 1092 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 1994 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Limnology written by Robert G. Wetzel and published by Gulf Professional Publishing. This book was released on 2001-04-06 with total page 1023 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a comparative treatment of topics accross lake, reservoir, and rive ecosystems. These analysis do indeed indicate differences among the properties of lakes, land-water interface regions, reservoirs, and rivers. Importantly, these analysis also indicate marked commonality in function.
Download or read book The Ecology of the Plankton Communities of Two Desert Reservoirs written by Tyler R. Sawyer and published by . This book was released on 2011 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 2010, a monthly sampling regimen was established to examine ecological differences in Saguaro Lake and Lake Pleasant, two central Arizona reservoirs. Lake Pleasant is relatively deep and clear, while Saguaro Lake is relatively shallow and turbid. Preliminary results indicated that phytoplankton biomass was greater by an order of magnitude in Saguaro Lake, and that community structure differed. The purpose of this investigation was to determine why the reservoirs are different, and focused on physical characteristics of the water column, nutrient concentration, community structure of phytoplankton and zooplankton, and trophic cascades induced by fish populations. I formulated the following hypotheses: 1) Top-down control varies between the two reservoirs. The presence of piscivore fish in Lake Pleasant results in high grazer and low primary producer biomass through trophic cascades. Conversely, Saguaro Lake is controlled from the bottom-up. This hypothesis was tested through monthly analysis of zooplankton and phytoplankton communities in each reservoir. Analyses of the nutritional value of phytoplankton and DNA based molecular prey preference of zooplankton provided insight on trophic interactions between phytoplankton and zooplankton. Data from the Arizona Game and Fish Department (AZGFD) provided information on the fish communities of the two reservoirs. 2) Nutrient loads differ for each reservoir. Greater nutrient concentrations yield greater primary producer biomass; I hypothesize that Saguaro Lake is more eutrophic, while Lake Pleasant is more oligotrophic. Lake Pleasant had a larger zooplankton abundance and biomass, a larger piscivore fish community, and smaller phytoplankton abundance compared to Saguaro Lake. Thus, I conclude that Lake Pleasant was controlled top-down by the large piscivore fish population and Saguaro Lake was controlled from the bottom-up by the nutrient load in the reservoir. Hypothesis 2 stated that Saguaro Lake contains more nutrients than Lake Pleasant. However, Lake Pleasant had higher concentrations of dissolved nitrogen and phosphorus than Saguaro Lake. Additionally, an extended period of low dissolved N:P ratios in Saguaro Lake indicated N limitation, favoring dominance of N-fixing filamentous cyanobacteria in the phytoplankton community in that reservoir.
Download or read book Boreal Environment Research written by and published by . This book was released on 1999 with total page 822 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Piscivorous Fish and Nutrient Availability on the Biomass and Community Size Structure of Phytoplankton and Zooplankton in 29 Temperate Lakes written by Pamela M. Dilworth-Christine and published by . This book was released on 1993 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has been hypothesized that the trophic structure of aquatic ecosystems is controlled by two sets of processes, often referred to as bottom-up and top-down. The bottom-up hypothesis postulates that nutrient limitation, and various physical-chemical factors directly or indirectly regulate the biomass and community structure of organisms at all levels of the food web. The top-down hypothesis postulates that predation by upper levels of the food web (specifically piscivorous fish) strongly influence the biomass, community size structure and productivity of organisms in the lower trophic categories. In this study we attempt to determine the strength of both bottom-up and top-down control on lower trophic level biomass and community size structure, in lakes of varying trophic status. During summer stratification, 29 temperate lakes of varying trophic status and fish species composition were sampled in Quebec and Ontario. This study found a strong relationship between nutrient availability and phytoplankton biomass, and between nutrient availability and zooplankton size structure. Bottom-up effects were quite strong at both the phytoplankton and zooplankton levels. Neither piscivorous fish presence nor indices of piscivorous fish abundance had a detectable effect on most indices of phytoplankton and zooplankton biomass and community size structure. Only cladoceran biomass and the variance in individual dry weight were higher in lakes where piscivorous fish were present. Piscivorous fish predation-effects were not evident at the phytoplankton level and were relatively weak at the zooplankton level. Total zooplankton biomass, crustacean biomass and cladoceran biomass were significant in explaining residual variation in the TP-Chl a model and improved this model's predictive ability by 24%, 18% and 22%, respectively. This study found that the effect of piscivorous fish did not depend on the concentration of total phosphorus in the 29 lakes. No evidence of interaction between trophic status and predation was determined. (Abstract shortened by UMI.).
Download or read book Asian Fisheries Science written by and published by . This book was released on 2003 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Archiv f r Hydrobiologie written by and published by . This book was released on 1997 with total page 900 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Regulating Zooplankton Biomass Abundance and Community Structure in a Southcentral Texas Reservoir written by Michele Dietzel Funk and published by . This book was released on 2013 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focused on zooplankton dynamics in a shallow hard water reservoir during summer months and the influence of reservoir water residence time and off-channel areas on zooplankton dynamics.
Download or read book Ecology Abstracts written by and published by . This book was released on 1997 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coverage: 1982- current; updated: monthly. This database covers current ecology research across a wide range of disciplines, reflecting recent advances in light of growing evidence regarding global environmental change and destruction. Major ares of subject coverage include: Algae/lichens, Animals, Annelids, Aquatic ecosystems, Arachnids, Arid zones, Birds, Brackish water, Bryophytes/pteridophytes, Coastal ecosystems, Conifers, Conservation, Control, Crustaceans, Ecosyst em studies, Fungi, Grasses, Grasslands, High altitude environments, Human ecology, Insects, Legumes, Mammals, Management, Microorganisms, Molluscs, Nematodes, Paleo-ecology, Plants, Pollution studies, Reptiles, River basins, Soil, TAiga/tundra, Terrestrial ecosystems, Vertebrates, Wetlands, Woodlands.
Download or read book Florida Scientist written by and published by . This book was released on 2000 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Zoology in the Middle East written by and published by . This book was released on 2005 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Complex Interactions in Lake Communities written by Stephen R. Carpenter and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: In its statutory authority (National Science Foundation Act of 1950, as amended), the NSF is directed to both initiate and support basic scientific research. In its Ecology Program, one mode of initiating research is to en courage the development of new ideas through advisory workshops. The NSF is specifically directed to strengthen our nation's research potential. In addition, stimulating new approaches to research will continue to be prominent in the coming years as federal attention is given to increasing the innovativeness and competitiveness of the U. S. in science and engineering. A decision to initiate a workshop does not arise de novo in the Ecology Program. Rather, it emerges from panel discussions, conversations with in vestigators at meetings or on the phone, and from discussions between pro gram officers in the Division of Biotic Systems and Resources. This workshop was developed to provide advice to the NSF and the lim nological community. Some NSF perceptions on future funding for ecolog ical research on lake communities are presented here. Researchers often mentioned a paucity of innovative lake ecology at the community level. This perception was accompanied by a certain frustration since lakes probably have the best empirical data base of any natural environment and should continue to lead in the development of ecological concepts. Members of NSF advisory panels sometimes expressed similar concerns during consid eration of proposals for lake research.
Download or read book Nutrient Criteria Technical Guidance Manual written by and published by . This book was released on 2000 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Restoration of Aquatic Ecosystems written by National Research Council and published by National Academies Press. This book was released on 1992-01-01 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aldo Leopold, father of the "land ethic," once said, "The time has come for science to busy itself with the earth itself. The first step is to reconstruct a sample of what we had to begin with." The concept he expressedâ€"restorationâ€"is defined in this comprehensive new volume that examines the prospects for repairing the damage society has done to the nation's aquatic resources: lakes, rivers and streams, and wetlands. Restoration of Aquatic Ecosystems outlines a national strategy for aquatic restoration, with practical recommendations, and features case studies of aquatic restoration activities around the country. The committee examines: Key concepts and techniques used in restoration. Common factors in successful restoration efforts. Threats to the health of the nation's aquatic ecosystems. Approaches to evaluation before, during, and after a restoration project. The emerging specialties of restoration and landscape ecology.
