948 resultados para Lake Shore and Michigan Southern Railway Company


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Monthly sediment and interstitial water samples were collected in a shallow Chinese freshwater lake (Lake Donghu) from three areas to determine if alkaline phosphatase activity (APA) plays an important role in phosphorus cycling in sediment. The seasonal variability in the kinetics of APA and other relevant parameters were investigated from 1995-1996. The phosphatase hydrolyzable phosphorus (PHP) fluctuated seasonally in interstitial water, peaking in the spring. A synchronous pattern was observed in chlorophyll a contents in surface water in general. The orthophosphate (o-P) concentrations in the interstitial water increased during the spring. An expected negative relationship between PHP and V-max of APA is not evident in interstitial water. The most striking feature of the two variables is their co-occurring, which can be explained in terms of an induction mechanism. It is argued that phosphatase activity mainly contributes to the driving force of o-P regeneration from PHP in interstitial water, supporting the development of phytoplankton biomass in spring. The V-max values in sediment increased during the summer, in Conjunction with lower K-m values in interstitial water that suggest a higher affinity for the substrate. The accumulation of organic matter in the sediment could be traced back to the breakdown of the algal spring bloom, which may stimulate APA with higher kinetic efficiency, by a combination of the higher V-max in sediments plus lower K-m values in interstitial water, in Summer. In summary, a focus On phosphatase and its substrate in annual scale may provide a useful framework for the development of novel P cycling, possible explanations for the absence of a clear relationship between PHP and APA were PHP released from the sediment which induced APA, and the presence of kinetically higher APA both in sediment and interstitial water which permitted summer mineralization of organic matter derived from the spring bloom to occur. The study highlighted the need for distinguishing functionally distinct extracellular enzymes between the sediment and interstitial water of lakes. (C) 2002 Elsevier Science Ltd. All rights reserved.

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Small fish communities were compared between the vegetated and vegetation-free regions of the Liangzi Lake, a shallow lake along the middle reach of the Yangtze River, China. Fish were sampled using 10 x 10 m(2) block nets and poisoning. Three samples were taken from either the near shore area or lake centre of each region. A total of 19 fish species were collected; all species occurred in the vegetated region but only 12 occurred in the vegetation-free region. The dominant small fish were Carassius auratus auratus in the vegetated region and Ctenogobius giurinus in the vegetation-free region. Diversity, density and biomass of small fishes were significantly higher in the vegetated region than in the vegetation-free region in both near shore and lake centre areas. In the vegetated region, density and biomass of small fishes was significantly higher, while species diversity significantly lower in the near shore area than in the lake centre. In the vegetation-free region, density of small fishes was significantly higher in the near shore area than in the lake centre area, but species diversity or biomass was unaffected by location.

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A fine-grid model (1/6degrees) covering the South China Sea (SCS), East China Sea and Japan/East Sea, which is embedded into a coarse-grid (3degrees) global model, was established to study the SCS circulation. In the present paper, we report the model-produced monthly and annual mean transport stream functions and sea surface heights(SSH) and their anomalies of the SCS. Comparison to the TOPEX/Poseidon data shows that the model-produced monthly sea surface height anomalies (SSHA) are in good agreement with altimeter measurements. Based on the results, the circulation of the SCS, especially the upper layer circulation, is discussed. In the surface layer, the western Philippine Sea water intrudes into the SCS through the Luzon Strait in autumn, winter and spring, but not in summer. However, as far as the whole water column is concerned, the water intrudes into the SCS through the Luzon Strait all the year round. This indicates that in summer the water still intrudes into the SCS in the subsurface and intermediate layers. The area near the northern continental slope of the SCS is dominated by a cyclonic circulation all the year round. The SCS Southern Anticyclonic Gyre, SE Vietnam Off-Shore Current in summertime and SCS Southern Cyclonic Gyre in wintertime are reproduced reasonably. The difference between the monthly averaged SSH and SSHA is significant, indicating the importance of the mean SSH in the SCS circulation.

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Highly pathogenic avian influenza H5N1 virus has swept west across the globe and caused serious debates on the roles of migratory birds in virus circulation since the first large-scale outbreak in migratory birds of Lake Qinghai, 2005. In May 2006, another outbreak struck Lake Qinghai and six novel strains were isolated. To elucidate these QH06 viruses, the six isolates were subjected to whole-genome sequencing. Phylogenetic analyses show that QH06 viruses are derived from the lineages of Lake Qinghai, 2005. Five of the six novel isolates are adjacent to the strain A/Cygnus olor/Croatia/1/05, and the last one is related to the strain A/duck/Novosibirsk/ 02/05, an isolate of the flyway. Antigenic analyses suggest that QH06 and QH05 viruses are similar to each other. These findings implicate that QH06 viruses of Lake Qinghai may travel back via migratory birds, though not ruling out the possibility of local circulation of viruses of Lake Qinghai.

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Lower member of the lower Ganchaigou Formation in the southwestern of Qaidam Basin is one of the main targeted exploration zones. With the advancement of exploration, the targets are gradually switching into the lithologic reservoirs and it is urgent to gain the more precise research results in distribution of sedimentary facies and sandstones. Guided by the theory of sequence stratigraphy and sedimentology as well as on the basis of many logging data, drillings, seismic data and chemical tests, the paper comprehensively analyzes the sedimentary facies and sandstones in the lower member of lower Ganchaigou Formation in the southern of Chaixi. According to the identification marks of the key interface in sequence stratigraphy, the key interfaces in lower member of lower Ganchaigou Formation in the southwestern of Qaidam Basin are identified as two third-order sequences SQ1、SQ2. By calibrating the synthetic seismogram, the seismic sequence, well drilling and logging sequences are united. Based on the works above, this paper chooses seven primary cross-sections and builds connecting-well stratigraphic correlation of seven main connecting-well sections. Ultimately, the high-resolution sequence stratigraphic frameworks in the lower member of the lower Ganchaigou Formation, which are uniform to logging and seismic data, are figured out. In terms of study on each sequence features, the main style of the base-level cycle overlay which forms the third-order sequence is confirmed. It contains asymmetric “becoming deep upward” style and symmetry style. Researching on the spreading characters of sequence stratigraphy indicates that SQ1 and SQ2 are rather thicker near northwest well Shashen 20 and Shaxin1 while they are quite thiner near Hongcan 1, Yuejin, Qie 4 and Dong8-Wu3, and the thickness of SQ1 is thicker than SQ2.Based on the deep analysis of the marks for depositional facies, it is proposed that the lake facies and braid river deltas facies mainly occurred in study areas. Besides, the sorts of sub-facies and micro-facies model are divided and described. Under the control of high-resolution sequence stratigraphic framework, three source directions from Arlarer Mountain、Qimantage Mountain and Dongchai Mountain are identified by using the features of heavy mineral assemblage and paleogeomorphy. In addition, regularities of distribution sedimentary facies in sequence stratigraphic framework are studied in accordance with research thinking of the "point" (single well) "line" (section) "face" (plane). In the stage of lower member in the lower Ganchaigou Formation in the southwestern of Qaidam Basin, it is at the early phrase of evolution of the lake basin with the gradual outspread and the rise of the lake level. Combined with physical analysis of reservoir sands formed in different sedimentary environment, the paper studies the style of favorable sandstone bodies that are underwater distributary channel of braided rive delta front, coarse sand in mouth bar and the sand body in sand flat of shore-shallow lacustrine facies. Finally, this article comprehensively analyzes the distribution relationship between sedimentary facies and favorable sandstone body and proposes the ideas that sequence SQ1 Yuejin area, well east 8-wu3 area, well qie4-qie1 area and well hongcan2 area are distributed areas of favorable sandstone.

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Wilkinson, Jane, Performing the Local and the Global: The Theatre Festivals of Lake Constance (Peter Lang, 2007), pp.286 RAE2008

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Thecamoebians were examined from 71 surface sediment samples collected from 21 lakes and ponds in the Greater Toronto Area to (1) elucidate the controls on faunal distribution in modern lake environments; and (2) to consider the utility of thecamoebians in quantitative studies of water quality change. This area was chosen because it includes a high density of kettle and other lakes which are threatened by urban development and where water quality has deteriorated locally as a result of contaminant inputs, particularly nutrients. Fifty-eight samples yielded statistically significant thecamoebian populations. The most diverse faunas (highest Shannon Diversity Index values) were recorded in lakes beyond the limits of urban development, although the faunas of all lakes showed signs of sub-optimal conditions. The assemblages were divided into five clusters using Q-mode cluster analysis, supported by Detrended Correspondence Analysis. Canonical Correspondence Analysis (CCA) was used to examine species-environment relationships and to explain the observed clusterings. Twenty-four measured environmental variables were considered, including water property attributes (e.g., pH, conductivity, dissolved oxygen), substrate characteristics, sediment-based phosphorus (Olsen P) and 11 environmentally available metals. The thecamoebian assemblages showed a strong association with phosphorus, reflecting the eutrophic status of many of the lakes, and locally to elevated conductivity measurements, which appear to reflect road salt inputs associated with winter de-icing operations. Substrate characteristics, total organic carbon and metal contaminants (particularly Cu and Mg) also influenced the faunas of some samples. A series of partial CCAs show that of the measured variables, sedimentary phosphorus has the largest influence on assemblage distribution, explaining 6.98% (P < 0.002) of the total variance. A transfer function was developed for sedimentary phosphorus (Olsen P) using 58 samples from 15 of the studied lakes. The best performing model was based on weighted averaging with inverse deshrinking (WA Inv, r jack 2= 0.33, RMSEP = 102.65 ppm). This model was applied to a small modern thecamoebian dataset from a eutrophic lake in northern Ontario to predict phosphorus and performed satisfactorily. This preliminary study confirms that thecamoebians have considerable potential as quantitative water quality indicators in urbanising regions, particularly in areas influenced by nutrient inputs and road salts.

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The long-term climatic and environmental history of Southeast Asia, and of Thailand in particular, is still fragmentary. Here we present a new 14C-dated, multi-proxy sediment record (TOC, C/N, CNS isotopes, Si, Zr, K, Ti, Rb, Ca elemental data, biogenic silica) for Lake Kumphawapi, the second largest natural lake in northeast Thailand. The data set provides a reconstruction of changes in lake status, groundwater fluctuations, and catchment run-off during the Holocene. A comparison of multiple sediment sequences and their proxies suggests that the summer monsoon was stronger between c. 9800 and 7000 cal yr BP. Lake status and water level changes around 7000 cal yr BP signify a shift to lower effective moisture. By c. 6500 cal yr BP parts of the lake had been transformed into a peatland, while areas of shallow water still occupied the deeper part of the basin until c. 5400–5200 cal yr BP. The driest interval in Kumphawapi's history occurred between c. 5200 and 3200 cal yr BP, when peat extended over large parts of the basin. After 3200 cal yr BP, the deepest part of the lake again turned into a wetland, which existed until c. 1600 cal yr BP. The observed lake-level rise after 1600 cal yr BP could have been caused by higher moisture availability, although increased human influence in the catchment cannot be ruled out. The present study highlights the use of multiple sediment sequences and proxies to study large lakes, such as Lake Kumphawapi in order to correctly assess the time transgressive response to past changes in hydroclimate conditions. Our new data set from northeast Thailand adds important palaeoclimatic information for a region in Southeast Asia and allows discussing Holocene monsoon variability and ITCZ movement in greater detail.

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Globally lakes bury and remineralise significant quantities of terrestrial C, and the associated flux of terrestrial C strongly influences their functioning. Changing deposition chemistry, land use and climate induced impacts on hydrology will affect soil biogeochemistry and terrestrial C export1 and hence lake ecology with potential feedbacks for regional and global C cycling. C and nitrogen stable isotope analysis (SIA) has identified the terrestrial subsidy of freshwater food webs. The approach relies on different 13C fractionation in aquatic and terrestrial primary producers, but also that inorganic C demands of aquatic primary producers are partly met by 13C depleted C from respiration of terrestrial C, and ‘old’ C derived from weathering of catchment geology. SIA thus fails to differentiate between the contributions of old and recently fixed terrestrial C. Natural abundance 14C can be used as an additional biomarker to untangle riverine food webs2 where aquatic and terrestrial δ 13C overlap, but may also be valuable for examining the age and origin of C in the lake. Primary production in lakes is based on dissolved inorganic C (DIC). DIC in alkaline lakes is partially derived from weathering of carbonaceous bedrock, a proportion of which is14C-free. The low 14C activity yields an artificial age offset leading samples to appear hundreds to thousands of years older than their actual age. As such, 14C can be used to identify the proportion of autochthonous C in the food-web. With terrestrial C inputs likely to increase, the origin and utilisation of ‘fossil’ or ‘recent’ allochthonous C in the food-web can also be determined. Stable isotopes and 14C were measured for biota, particulate organic matter (POM), DIC and dissolved organic carbon (DOC) from Lough Erne, Northern Ireland, a humic alkaline lake. Temporal and spatial variation was evident in DIC, DOC and POM C isotopes with implications for the fluctuation in terrestrial export processes. Ramped pyrolysis of lake surface sediment indicates the burial of two C components. 14C activity (507 ± 30 BP) of sediment combusted at 400˚C was consistent with algal values and younger than bulk sediment values (1097 ± 30 BP). The sample was subsequently combusted at 850˚C, yielding 14C values (1471 ± 30 BP) older than the bulk sediment age, suggesting that fossil terrestrial carbon is also buried in the sediment. Stable isotopes in the food web indicate that terrestrial organic C is also utilised by lake organisms. High winter δ 15N values in calanoid zooplankton (δ 15N = 24%¸) relative to phytoplankton and POM (δ 15N = 6h and 12h respectively) may reflect several microbial trophic levels between terrestrial C and calanoids. Furthermore winter calanoid 14C ages are consistent with DOC from an inflowing river (75 ± 24 BP), not phytoplankton (367 ± 70 BP). Summer calanoid δ 13C, δ 15N and 14C (345 ± 80 BP) indicate greater reliance on phytoplankton.

1 Monteith, D.T et al., (2007) Dissolved organic carbon trends resulting from changes in atmospheric deposition chemistry. Nature, 450:537-535

2 Caraco, N., et al.,(2010) Millennial-aged organic carbon subsidies to a modern river food web. Ecology,91: 2385-2393.

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We report two new occurrences of Mysis salemaai, a conservationally important glacial relict at the southern limit of its range, in Castlewellan Lake and Lough Scolban, in the North of Ireland. This increases the number of lakes in Ireland where the species has been recorded to thirteen. We consider lake area and maximum lake depth as factors that might determine the long-term survival of M. salemaai populations and show that these populations tend to occur in relatively large, deep, lakes. We also show that population densities in Lough Neagh and Lough Erne are declining.

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Dissertação mest., Gestão da água e da costa, Universidade do Algarve, 2007

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Survey map of the Second Welland Canal created by the Welland Canal Company showing the areas in and around Port Colborne. Identified structures associated with the Canal include Lighthouse, Pier Light, Old Lock House, Collector's Office, Harbour Master's House, Canal Boundary, Back Ditch, Reserved Back Ditch, Basin, Light-Keeper's House and Ferry Recess. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks and businesses are also identified and include Gordon's Woodyard, Welland Rail Road, Welland Railway Elevator and Proposed Elevator, W.R.R. Flour Shed, Roman Catholic Church, School House, Sandhills, Lake Erie, and the High Water Mark. Streets running parallel to Canal include King St., West St., East St., Queen St., Hamilton St., and the Road Allowance are labelled. Streets running perpendicular to Canal include Kent St., Victoria St., Adelaide St., SugarLoaf St., George St., Alexandrina St., William St., Fort Erie St., Lake Rd., and New Road to Dutch Settlement are also labelled. Property owners and leasers as well as buildings on lots are also idenitified and noted as follows: Adams estate, J. Towhig, J.C. Kerr, Mrs. Hill, S. Cooke, Mrs. Yocum, W.T. Cooke, P. Wintermute, J. Shickluna, William Cooke, J. McChesney, John Beatty, W. Robertson, John Gordon, T. Armstrong, John Harper, George Keefer, Estate of James Black, Thomas Park, N. Higgins, S. Hopkins, and L.G. Cartier. Map of the Village of Port Colborne. Being Lot No. 27 and part of Lot No. 28 in the 1st Con. Township of HUMBERSTONE. Scale 2 Chs. per Inch. land shaded in RED Owned by DEPT. Do. Do. BLUE Sold to the COUNTY of WELLAND

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Indenture of release by executors between Richard Miller, John L. Ranney and Richard Woodruff, all of St. Catharines and Joseph A. Woodruff of Clifton, all executors of the will of Samuel Zimmerman of the first part and The Great Western Railway Company of the second part. Parties of the second part have exonerated parties of the first part to undertake and complete the Sarnia branch of the railway. Also, parties of the first part believe they are entitled to compensation as the death of Zimmerman was caused while travelling on one of the carriages belonging to said company. A sum of $150,000 was agreed upon to be paid to the executors by the Great Western Railway Company, September 7, 1858.