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North Shore (north + shore)
Terms modified by North Shore Selected AbstractsEffects of hydrogeomorphic region, catchment storage and mature forest on baseflow and snowmelt stream water quality in second-order Lake Superior Basin tributariesFRESHWATER BIOLOGY, Issue 5 2003Naomi E. Detenbeck SUMMARY 1. In this study we predict stream sensitivity to non-point source pollution based on the non-linear responses of hydrological regimes and associated loadings of non-point source pollutants to catchment properties. We assessed two hydrologically based thresholds of impairment, one for catchment storage (5,10%) and one for mature forest (<50% versus >60% of catchment in mature forest cover) across two different hydrogeomorphic regions within the Northern Lakes and Forest (NLF) ecoregion: the North Shore [predominantly within the North Shore Highlands Ecological Unit] and the South Shore (predominantly within the Lake Superior Clay Plain Ecological Unit). Water quality samples were collected and analysed during peak snowmelt and baseflow conditions from 24 second-order streams grouped as follows: three in each region × catchment storage × mature forest class. 2. Water quality was affected by a combination of regional influences, catchment storage and mature forest. Regional differences were significant for suspended solids, phosphorus, nitrogen: phosphorus ratios, dissolved organic carbon (DOC) and alkalinity. Catchment storage was significantly correlated with dissolved silica during the early to mid-growing season, and with DOC, specific conductance and alkalinity during all seasons. Total nitrogen and dissolved nitrogen were consistently less in low mature forest than in high mature forest catchments. Catchment storage interacted with the influence of mature forest for only two metrics: colour and the soluble inorganic nitrogen : phosphorus ratio. 3. Significant interaction terms (region by mature forest or region by storage) suggest differences in regional sensitivity for conductance, alkalinity, total organic carbon, and colour, as well as possible shifts in thresholds of impact across region or mature forest class. 4. Use of the NLF Ecoregion alone as a basis for setting regional water quality criteria would lead to the misinterpretation of reference condition and assessment of condition. There were pronounced differences in background water quality between the North and South Shore streams, particularly for parameters related to differences in soil parent material and glacial history. A stratified random sampling design for baseflow and snowmelt stream water quality based on both hydrogeomorphic region and catchment attributes improves assessments of both reference condition and differences in regional sensitivity. [source] A Retrospective Look at the Water Resource Management Policies in Nassau County, Long Island, New York,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2008Daniel J. St. Germain Abstract:, The residents of Nassau County Long Island, New York receive all of their potable drinking water from the Upper Glacial, Jameco/Magothy (Magothy), North Shore, and Lloyd aquifers. As the population of Nassau County grew from 1930 to 1970, the demand on the ground-water resources also grew. However, no one was looking at the potential impact of withdrawing up to 180 mgd (7.9 m3/s) by over 50 independent water purveyors. Some coastal community wells on the north and south shores of Nassau County were being impacted by saltwater intrusion. The New York State Legislature formed a commission to look into the water resources in 1972. The commission projected extensive population growth and a corresponding increase in pumping resulting in a projected 93.5 to 123 mgd (4.1 to 5.5 m3/s) deficit by 2000. In 1986, the New York Legislature passed legislation to strengthen the well permit program and also establish a moratorium on new withdrawals from the Lloyd aquifer to protect the coastal community's only remaining supply of drinking water. Over 30 years has passed since the New York Legislature made these population and pumping projections and it is time to take a look at the accuracy of the projections that led to the moratorium. United States Census data shows that the population of Nassau County did not increase but decreased from 1970 to 2000. Records show that pumping in Nassau County was relatively stable fluctuating between 170 and 200 mgd (7.5 to 8.8 m3/s) from 1970 to 2004, well below the projection of 242 to 321 mgd (10.6 to 14.1 m3/s). Therefore, the population and water demand never grew to projected values and the projected threat to the coastal communities has diminished. With a stable population and water demand, its time to take a fresh look at proactive ground-water resource management in Nassau County. One example of proactive ground-water management that is being considered in New Jersey where conditions are similar uses a ground-water flow model to balance ground water withdrawals, an interconnection model to match supply with demand using available interconnections, and a hydraulic model to balance flow in water mains. New Jersey also conducted an interconnection study to look into how systems with excess capacity could be used to balance withdrawals in stressed aquifer areas with withdrawals in unstressed areas. Using these proactive ground-water management tools, ground-water extraction could be balanced across Nassau County to mitigate potential impacts from saltwater intrusion and provide most water purveyors with a redundant supply that could be used during water emergencies. [source] Dependence between extreme sea surge, river flow and precipitation in eastern BritainINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 10 2002Cecilia Svensson Abstract Flooding in estuaries may be caused by both high river flows and by high sea levels. In order to investigate whether these tend to occur simultaneously in eastern Britain, the dependence between high sea surge (observed sea level minus predicted astronomical tide), river flow and precipitation was studied using a measure of dependence specially developed for extremal dependence. Extreme events were interpreted using meteorological maps. This new analysis found that the strongest flow,surge dependence occurs between river flow on the north shore of the Firth of Forth and sea surge at Aberdeen, Wick and Lerwick. In contrast to most other catchments in eastern Britain, the area to the north of the Firth of Forth is not sheltered from south-westerly winds by any major topographical barrier. Therefore, precipitation from this direction may be orographically enhanced as it encounters the hills on the northern side of the firth, and high river flows may ensue. Events resulting in both high river flow and surge in the northern part of the study area were found to be caused by cyclones travelling north-eastward to the north of Scotland. High surge events, only, were associated with similar storm tracks, but without much precipitation from the fronts. High river flows, only, were associated with rain-bearing east,west-directed fronts over northern Britain, with slow-moving depressions located over or to the west of the British Isles where they are unable to generate a strong surge in the North Sea. The dependence between river flow and surge was found to be stronger during winter than summer, and a lagged analysis revealed that the dependence is strongest when flow and surge occur on the same day, but was also strong for lags of plus and minus 1 day. For precipitation, the dependence with both flow and surge is strongest when precipitation precedes them by 1 day. Copyright © 2002 Royal Meteorological Society. [source] Activity budget and diving behavior of gray whales (Eschrichtius robustus) in feeding grounds off coastal British ColumbiaMARINE MAMMAL SCIENCE, Issue 3 2008Lei Lani Stelle Abstract Behavior and diving patterns of summer resident gray whales (Eschrichtius robustus) foraging on mysids were studied in coastal bays along the north shore of Queen Charlotte Strait, British Columbia. In this region, gray whales were found to feed primarily on planktonic prey rather than on the benthos as in their primary feeding areas further north. During the summers of 1999 and 2000, whales spent most of their time actively feeding or searching for prey (77%), whereas only 15% of their time was spent traveling and 8% socializing. The majority of the dives were short; the mean dive duration was 2.24 min with approximately three respirations per surfacing and 15 s between blows. Whales dove frequently (26.7 h,1), spending only 17% of their time at the surface with an overall blow rate of 1.14 respirations per minute. Activity states were characterized by significantly different diving and respiratory parameters; feeding whales dove more frequently, with shorter intervals between respirations, thus spending less time at the surface compared to when traveling or searching. This diving pattern differs from benthic-feeding whales and likely optimizes capture of the mobile mysid swarms in shallow waters. [source] Origin and genetic diversity of Western European populations of the potato cyst nematode (Globodera pallida) inferred from mitochondrial sequences and microsatellite lociMOLECULAR ECOLOGY, Issue 9 2008O. PLANTARD Abstract Native to South America, the potato cyst nematode Globodera pallida is one of the principal pests of Andean potato crops and is also an important global pest following its introduction to Europe, Africa, North America, Asia and Oceania. Building on earlier work showing a clear south to north phylogeographic pattern in Peruvian populations, we have been able to identify the origin of Western European populations with high accuracy. They are all derived from a single restricted area in the extreme south of Peru, located between the north shore of the Lake Titicaca and Cusco. Only four cytochrome b haplotypes are found in Western Europe, one of them being also found in some populations of this area of southern Peru. The allelic richness at seven microsatellite loci observed in the Western European populations, although only one-third of that observed in this part of southern Peru, is comparable to the allelic richness observed in the northern region of Peru. This result could be explained by the fact that most of the genetic variability observed at the scale of a field or even of a region is already observed at the scale of a single plant within a field. Thus, even introduction via a single infected potato plant could result in the relatively high genetic variability observed in Western Europe. This finding has important consequences for the control of this pest and the development of quarantine measures. [source] ROCK SURFACE HARDNESS AS AN INDICATION OF EXPOSURE AGE: AN ARCHAEOLOGICAL APPLICATION OF THE SCHMIDT HAMMER,ARCHAEOMETRY, Issue 1 2000M. W. BETTS A Schmidt Hammer was employed in evaluating the surface hardness of rocks which line ancient anthropogenic pit features, known as Pukaskwa pits, on the north shore of Lake Superior, Canada. This technique offers a possible new method of producing relative ana absolute dates for such exposed stone features Analysis of the data has provided a relative chronology for the pit features, representing two distinct construction phases. The range of absolute dates generated from the data indicates that the pits were likely constructed by Blackduck peoples c. 900 to 400 years BP. [source] Mathematics of the Ideal PavilionARCHITECTURAL DESIGN, Issue 5 2009Neil Spiller Abstract Neil Spiller flees the nihilism of the shards and blobs of the last three decades in architecture and finds redemption on the north shore of Lakeside Way in Kielder Water, Northumbria. He describes how with this exquisitely tailored pavilion sixteen*(makers) are opening the way for a new way of working. Copyright © 2009 John Wiley & Sons, Ltd. [source] Stratigraphy and sedimentation of the stratotype sections of the Catfish Creek Drift Formation between Bradtville and Plum Point, north shore, Lake Erie, southwestern Ontario, CanadaBOREAS, Issue 2 2005ALEKSIS DREIMANIS Dreimanis, A. & Gibbard, P. 2005 (May): Stratigraphy and sedimentation of the stratotype sections of the Catfish Creek Drift Formation between Bradtville and Plum Point, north shore, Lake Erie, southwestern Ontario, Canada. Boreas, Vol. 34, pp. 101,122. Oslo. ISSN 0300,9483. The Catfish Creek Drift Formation is a significant and extensive lithostratigraphical marker unit in SW Ontario. Here the stratotype, exposed in the Lake Erie bluffs of the Plum Point-Bradtville (Grandview) area south of London, Ontario, Canada, is proposed. It consists of subglacial and proglacial sediments deposited at the beginning of the Nissouri Phase of the Wisconsinan glaciation. In the 2.5-km-long stratotype section, the Catfish Creek Drift consists of 9 members. Five of them, the Dunwich and Grandview I-IV members, mainly consist of till, with minor components of stratified drift. The Dunwich till was deposited by the Huron-Georgian Bay lobe, but the Grandview I-IV tills by the Erie lobe. The Zettler Farm Member consists of co-lobal till in the central part of the section and of a proglacial waterlain flow diamicton and a subglacial undermelt diamicton in the SW part. Three members consist entirely of stratified drift; the glaciolacustrine silty and clayey Waite Farm Member, the ice-marginal deltaic Oosprink Farm Member and the Boy Scout Camp Member , deposited by meltwater streams in subglacial channels. The sequence of interbedded till and stratified drift represents the oscillating advance of the Laurentide Ice Sheet in the Lake Erie basin. [source] | ||||||||||||||||