986 resultados para Upper Lakes Shipping, Ltd.
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This paper introduces VERTEX, a multi-disciplinary research program dealing with various aspects of particle transport in the upper, high-energy layers (0-2000 m) of the ocean. Background information is presented on hydrography, biological composition of trapped particulates, and major component fluxes observed on a cruise off central California (VERTEX I). Organic C fluxes measured with two trap systems are compared with several other estimates taken from the literature. The intent of this overview paper is to provide a common setting in an economical manner, and avoid undue repetition of background and ancillary information in subsequent publications. (PDF is 43 pages).
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We hypothesize that the richness and diversity of the biota in Lake Moraine (42°50’47”N, 75°31’39”W) in New York have been negatively impacted by 60 years of macrophyte and algae management to control Eurasian watermilfoil ( Myriophyllum spicatum L.) and associated noxious plants. To test this hypothesis we compare water quality characteristics, richness and selected indicators of plant diversity, zooplankton, benthic macroinvertebrates and fish in Lake Moraine with those in nearby Hatch Lake (42°50’06”N, 75°40’67”W). The latter is of similar size and would be expected to have similar biota, but has not been subjected to management. Measurements of temperature, pH, oxygen, conductivity, Secchi transparency, calcium, total phosphorus and nitrites + nitrates are comparable. Taxa richness and the diversity indices applied to the aquatic macrophytes are similar in both lakes. (PDF has 8 pages.)
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The nature of aquatic plant communities often defines benthic habitat within oligotrophic and mesotrophic lakes and lake management increasingly recognizes the importance of maintaining plant diversity in order to sustain biological diversity and capacity within lakes. We have developed simple statistical relationships between key physical and vegetation variables that define the habitat requirements, or “habitat-templates”, of key vegetation types to facilitate management of plant communities in New Zealand lakes. Statistical relationships were derived from two datasets. The first was a multi-lake dataset to determine the effects of water level fluctuation and water clarity. The second dataset was from a comprehensive shoreline survey of Lake Wanaka, which allowed us to examine within-lake variables such as beach slope and wave action. Sufficient statistical relationships were established to develop a habitat template for each of the major species or assemblages. The relationships suggested that the extent and diversity of shallow-growing species was related to a combination of the extent of water level fluctuation and wave exposure. (PDF contains 9 pages.)
Distribution and Density of Vegetative Hydrilla Propagules in the Sediments of Two New Zealand Lakes
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The distribution and density of hydrilla (Hydrilla verticillata (L.f.)Royle) turions and tubers in two New Zealand lakes were assessed by sampling cores of sediment from Lakes Tutira and Waikapiro each year from 1994 to 1997. Turion and tuber density differed with water depth, with maximum numbers of tubers and turions found in the 1-2 m and 1.5-4m water depth ranges respectively. A high turion to tuber ratio was observed, with turions accounting for over 80% of propagules. The relatively low numbers of turions and tubers compared with other reports, and the distribution of most tubers within the shallow water is likely to be associated with black swan grazing (Cygnus atratus Latham), with maintains a canopy of hydrilla consistently 1 m below the water surface.
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Cambodia is one of the poorest countries in the world; much of its population live in rural areas and many live below the local poverty line. The management of common property aquatic resources is of over-riding importance to food security and sustainable rural development in Cambodia. The key groups of poor people who use aquatic resources as part of their diverse livelihoods portfolios are subsistence fishers, small-scale aquaculture practitioners and aquatic resources collectors. Subsistence fishers access mainly the rivers, lakes and inundated forests in Tonle Sap provinces, the lower Mekong and Bassac regions and the upper part of the Mekong. Small-scale aquaculture and/or the collection of aquatic resources are most important in provinces that are not rich in fisheries resources including Kompong Speu, Ratnakiri, Mondulkiri, Preah Vihear and Ortdar Meanchey. Freshwater capture fisheries probably contribute more to national food security and the national economy in Cambodia than in any other country in the world. (19 p.)
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Florida’s large number of shallow lakes, warm climate and long growing season have contributed to the development of excessive growths of aquatic macrophytes that have seriously interfered with many water use activities. The introduction of exotic aquatic macrophyte species such as hydrilla ( Hydrilla verticillata ) have added significantly to aquatic plant problems in Florida lakes. The use of grass carp ( Ctenopharyngodon idella ) can be an effective and economical control for aquatic vegetation such as hydrilla. Early stocking rates (24 to 74 grass carp per hectare of lake area) resulted in grass carp consumption rates that vastly exceeded the growth rates of the aquatic plants and often resulted in the total loss of all submersed vegetation. This study looked at 38 Florida lakes that had been stocked with grass carp for 3 to 10 years with stocking rates ranging from < 1 to 59 grass carp per hectare of lake and 1 to 207 grass carp per hectare of vegetation to determine the long term effects of grass carp on aquatic macrophyte communities. The median PAC (percent area coverage) value of aquatic macrophytes for the study lakes after they were stocked with grass carp was 14% and the median PVI (percent volume infested) value of aquatic macrophytes was 2%. Only lakes stocked with less than 25 to 30 fish per hectare of vegetation tended to have higher than median PAC and PVI values. When grass carp are stocked at levels of > 25 to 30 fish per hectare of vegetation the complete control of aquatic vegetation can be achieved, with the exception of a few species of plants that grass carp have extreme difficulty consuming. If the management goal for a lake is to control some of the problem aquatic plants while maintaining a small population of predominately unpalatable aquatic plants, grass carp can be stocked at approximately 25 to 30 fish per hectare of vegetation.
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The specialist aquatic herbivore Euhrychiopsis lecontei (Dietz) is currently being researched as a potential biological control agent for Eurasian watermilfoil (Myriophyllum spicatum L.). Our research in Wisconsin focused on 1) determining milfoil weevil distribution across lakes, 2) assessing limnological characteristics associated with their abundance, and 3) evaluating milfoil weevil augmentation as a practical management tool for controlling Eurasian watermilfoil.
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This is a student paper done for a University of California Berkeley Zoology class. Since UCB didn't have its own marine lab at the time, it rented space at Hopkins Marine Station where this work was done. Cadet Hand earned his Ph.D. from Berkeley and went on to become Director of the Bodega Marine Laboratory. Donald Putnam Abbott also earned his Ph.D. from Berkeley and later became a Stanford professor at Hopkins Marine Station. (PDF contains 26 pages)
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Ichthyoplankton surveys in the Potomac River and Upper Chesapeake Bay were carried out in 1989 to estimate striped bass egg productions, age specific spawning biomasses of adult females, cohort-specific larval growth and mortality rates, and hatch dates of 8.0 mm larvae survivors. Possible consequences to recruitment of environmental factors were examined in 1989 and for data collected in 1987-1988. The temporal and spatial occurrences and distributions of eggs and larvae In both spawning areas are described and discussed in relation to environmental factors (temperature, rainfall, river discharge, pH, conductivity, zooplankton abundances) (PDF contains 319 pages)
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Between 1994 and 1997, 258 tissue and 178 sediment samples were analyzed for chlorpyrifos throughout the coastal United States and the Great Lakes. Subsequently, 95 of the 1997 tissue samples were reanalyzed for endosulfan. Tissue chlorpyrifos concentrations, which exceeded the 90th percentile, were found in coastal regions known to have high agricultural use rates but also strongly correlated with sites near high population. The highest concentrations of endosulfans in contrast, were generally limited to agricultural regions of the country. Detections of chlorpyrifos at several Alaskan sites suggest an atmospheric transport mechanism. Many Great Lakes sites had chlorpyrifos tissue concentrations above the 90th percentile which decreased with increasing distance from the Corn Belt region (Iowa, Indiana, Illinois, and Wisconsin) where most agriculturally applied chlorpyrifos is used. Correlation analysis suggests that fluvial discharge is the primary transport pathway on the Atlantic and Gulf of Mexico coasts for chlorpyrifos but not necessarily for endosulfans. (PDF contains 28 pages)
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This manual presents geographic information by state of occurrence, and descriptions of the socio-economic impact created by the invasion of non-indigenous and native transplanted animal species in the Laurentian Great Lakes and the coastal waters of the United States. It is not a comprehensive literature review, but rather is intended as a primer for those unfamiliar with the socio-economic impacts of invasive aquatic and marine animals. Readers should also note that the information contained in this manual is current as of its publication date. New information and new species are routinely being added to the wider literature base. Most of the information was gathered from a number of web sites maintained by government agencies, commissions, academic institutions and museums. Additional information was taken from the primary and secondary literature. This manual focuses on socio-economic consequences of invasive species. Thus, ecological impacts, when noted in the literature, are not discussed unless a connection to socio-economic factors can be made. For a majority of the species listed, either the impact of their invasion is not understood, or it is not published in sources surveyed. In the species summaries, sources of information are cited except for information from the U.S. Geological Survey’s (USGS) Nonindigenous Aquatic Species Database http://nas.er.usgs.gov. This website formed the base information used in creating tables on geographic distribution, and in many of the species summaries provided. Thus, whenever information is given without specific author/source and date citation, it has come from this comprehensive source. (PDF contains 90 pages)
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Cambodia is one of the poorest countries in the world; much of its population live in rural areas and many live below the local poverty line. The management of common property aquatic resources is of over-riding importance to food security and sustainable rural development in Cambodia. Aquatic resources are utilized principally by subsistence fishers and the landless, for whom aquatic resource use is an important livelihood activity. Subsistence fishers access mainly the rivers, lakes and inundated forests in Tonle Sap provinces, the lower Mekong and Bassac regions and the upper part of the Mekong. Freshwater capture fisheries probably contribute more to national food security and the national economy in Cambodia than in any other country in the world. (PDF contains 52 pages)
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Executive Summary: Observations show that warming of the climate is unequivocal. The global warming observed over the past 50 years is due primarily to human-induced emissions of heat-trapping gases. These emissions come mainly from the burning of fossil fuels (coal, oil, and gas), with important contributions from the clearing of forests, agricultural practices, and other activities. Warming over this century is projected to be considerably greater than over the last century. The global average temperature since 1900 has risen by about 1.5ºF. By 2100, it is projected to rise another 2 to 11.5ºF. The U.S. average temperature has risen by a comparable amount and is very likely to rise more than the global average over this century, with some variation from place to place. Several factors will determine future temperature increases. Increases at the lower end of this range are more likely if global heat-trapping gas emissions are cut substantially. If emissions continue to rise at or near current rates, temperature increases are more likely to be near the upper end of the range. Volcanic eruptions or other natural variations could temporarily counteract some of the human-induced warming, slowing the rise in global temperature, but these effects would only last a few years. Reducing emissions of carbon dioxide would lessen warming over this century and beyond. Sizable early cuts in emissions would significantly reduce the pace and the overall amount of climate change. Earlier cuts in emissions would have a greater effect in reducing climate change than comparable reductions made later. In addition, reducing emissions of some shorter-lived heat-trapping gases, such as methane, and some types of particles, such as soot, would begin to reduce warming within weeks to decades. Climate-related changes have already been observed globally and in the United States. These include increases in air and water temperatures, reduced frost days, increased frequency and intensity of heavy downpours, a rise in sea level, and reduced snow cover, glaciers, permafrost, and sea ice. A longer ice-free period on lakes and rivers, lengthening of the growing season, and increased water vapor in the atmosphere have also been observed. Over the past 30 years, temperatures have risen faster in winter than in any other season, with average winter temperatures in the Midwest and northern Great Plains increasing more than 7ºF. Some of the changes have been faster than previous assessments had suggested. These climate-related changes are expected to continue while new ones develop. Likely future changes for the United States and surrounding coastal waters include more intense hurricanes with related increases in wind, rain, and storm surges (but not necessarily an increase in the number of these storms that make landfall), as well as drier conditions in the Southwest and Caribbean. These changes will affect human health, water supply, agriculture, coastal areas, and many other aspects of society and the natural environment. This report synthesizes information from a wide variety of scientific assessments (see page 7) and recently published research to summarize what is known about the observed and projected consequences of climate change on the United States. It combines analysis of impacts on various sectors such as energy, water, and transportation at the national level with an assessment of key impacts on specific regions of the United States. For example, sea-level rise will increase risks of erosion, storm surge damage, and flooding for coastal communities, especially in the Southeast and parts of Alaska. Reduced snowpack and earlier snow melt will alter the timing and amount of water supplies, posing significant challenges for water resource management in the West. (PDF contains 196 pages)
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El objetivo de este trabajo es presentar un marco conceptual integrador de la literatura de capital intelectual. A partir de él, se analizará la elaboración de informes de capital intelectual en Asia, en particular, es una empresa con una posición competitiva privilegiada en India: Reliance Industries LTD.
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Background: Vitamin K has been related to glucose metabolism, insulin sensitivity and diabetes. Because inflammation underlies all these metabolic conditions, it is plausible that the potential role of vitamin K in glucose metabolism occurs through the modulation of cytokines and related molecules. The purpose of the study was to assess the associations between dietary intake of vitamin K and peripheral adipokines and other metabolic risk markers related to insulin resistance and type 2 diabetes mellitus. Methods: Cross-sectional and longitudinal assessments of these associations in 510 elderly participants recruited in the PREDIMED centers of Reus and Barcelona (Spain). We determined 1-year changes in dietary phylloquinone intake estimated by food frequency questionnaires, serum inflammatory cytokines and other metabolic risk markers. Results: In the cross-sectional analysis at baseline no significant associations were found between dietary phylloquinone intake and the rest of metabolic risk markers evaluated, with exception of a negative association with plasminogen activator inhibitor-1. After 1-year of follow-up, subjects in the upper tertile of changes in dietary phylloquinone intake showed a greater reduction in ghrelin (-15.0%), glucose-dependent insulinotropic peptide (-12.9%), glucagon-like peptide-1 (-17.6%), IL-6 (-27.9%), leptin (-10.3%), TNF (-26.9%) and visfatin (-24.9%) plasma concentrations than those in the lowest tertile (all p<0.05). Conclusion: These results show that dietary phylloquinone intake is associated with an improvement of cytokines and other markers related to insulin resistance and diabetes, thus extending the potential protection by dietary phylloquinone on chronic inflammatory diseases.