Postglacial vegetation and climate dynamics in the Seymour‐Belize Inlet Complex,central coastal British Columbia,Canada: palynological evidence from Tiny Lake     

Jennifer M. Galloway  Christine T. Doherty  R. Timothy Patterson  Helen M. Roe 《第四纪科学杂志》2009,24(4):322-335

A pollen‐based study from Tiny Lake in the Seymour‐Belize Inlet Complex of central coastal British Columbia, Canada, permits an evaluation of the dynamic response of coastal temperate rainforests to postglacial climate change. Open Pinus parklands grew at the site during the early Lateglacial when the climate was cool and dry, but more humid conditions in the later phases of the Lateglacial permitted mesophytic conifers to colonise the region. Early Holocene conditions were warmer than present and a successional mosaic of Tsuga heterophylla and Alnus occurred at Tiny Lake. Climate cooling and moistening at 8740 ± 70 ¹⁴C a BP initiated the development of closed, late successional T. heterophylla–Cupressaceae forests, which achieved modern character after 6860 ± 50 ¹⁴C a BP, when a temperate and very wet climate became established. The onset of early Holocene climate cooling and moistening at Tiny Lake may have preceded change at more southern locations, including within the Seymour‐Belize Inlet Complex, on a meso‐ to synoptic scale. This would suggest that an early Holocene intensification of the Aleutian Low pressure system was an important influence on forest dynamics in the Seymour‐Belize Inlet Complex and that the study region was located near the southern extent of immediate influence of this semi‐permanent air mass. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

An analysis of morphological characters of Owenia useful to distinguish species: description of three new species of Owenia (Oweniidae: Polychaeta) from Australian waters     

Evan Ford  & Pat Hutchings 《Marine Ecology》2005,26(3-4):181-196

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Cultivating new technologies     

Glyn Ford 《Marine Policy》1985,9(4):258-259

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Diversity and community structure of epibenthic invertebrates and fish in the North Sea   总被引：5，自引：3，他引：5  

Callaway  R.; Alsvag  J.; de Boois  I.; Cotter  J.; Ford  A.; Hinz  H.; Jennings  S.; Kroncke  I.; Lancaster  J.; Piet  G.; Prince  P.; Ehrich  S. 《ICES Journal of Marine Science》2002,59(6):1199-1214

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Chasing a 'loose and baggy monster': almshouses and the geography of charity     

John R. Bryson  Mark McGuiness  & Robert G. Ford 《Area》2002,34(1):48-58

This paper goes some way towards redressing the lack of geographical literature on charity through exploring the geography of the British domestic charitable sector. The size and geography of the third sector is outlined, followed by an analysis of how almshouses can be understood as inherently geographical and deeply embedded in local social networks of inclusion as well as exclusion.  相似文献   

Geochemistry of Tertiary tholeiites and picrites from Qeqertarssuaq (Disko Island) and Nuussuaq, West Greenland with implications for the mineral potential of comagmatic intrusions   总被引：10，自引：0，他引：10  

Peter C. Lightfoot  Christopher J. Hawkesworth  Kevin Olshefsky  Tony Green  Will Doherty  Reid R. Keays 《Contributions to Mineralogy and Petrology》1997,128(2-3):139-163

Tertiary continental flood basalts on Qeqertarssuaq and Nuussuaq in West Greenland contain ～3?km of picrites and variably contaminated tholeiites. The picrites are in the Naujánguit member of the Vaïgat Formation and they have 7–29?wt% MgO, La/Sm?=?0.9–2.1, and ¹⁴³Nd/¹⁴⁴Nd?=?0.51263–0.51307. They appear to have crystallised from high-Mg parental magmas (14.4–16.4?wt% MgO) with isotope and trace element ratios similar to recent Icelandic picrites. Discrete horizons of tholeiites, including the Asûk and?Kûgánguaq, have elevated SiO₂ (50–58 wt%), La/Sm?=?3–7, ⁸⁷Sr/⁸⁶Sr?=?0.70550–0.71224, and low ¹⁴³Nd/¹⁴⁴Nd?=?0.51234–0.51174. These lavas have low Cu and Ni abundances (typically 10–50?ppm Ni or Cu), and in the case of the Asûk on Qeqertarssuaq, they contain droplets of native iron. The low Cu and Ni contents are attributed to scavenging by magmatic sulphides formed in response to crustal contamination of picritic magmas. Two contamination trends are recognised, one to a sediment end-member with high Th/Nb and Archaean model Nd ages, and the other to a meta-igneous component with high La/Sm, low Th/Nb and Rb/Nb, and Proterozoic source ages. Overall, ²⁰⁶Pb/²⁰⁴Pb varies from 16.47–21.68. Both contamination trends are associated with low Cu and Ni, and high SiO₂, and it is argued that the magmatic sulphides were triggered by the increases in silica, rather than simply by the introduction of additional crustal-derived sulphur. Geochemically, the Asûk and Kûgánguaq rocks resemble the most contaminated Nadezhdinsky lavas of the Siberian Trap, which are widely regarded as the source of the Ni and Cu mineralisation in the giant Noril'sk deposits. Mass balance considerations indicate that the parental liquids to the contaminated magmas contained sufficient Ni, Cu, S and platinum group elements to form substantial magmatic sulphide deposits. However, unlike the lavas at Noril'sk, the contaminated (low Cu and Ni) West Greenland basalts are in isolated units with no evidence for a gradual recovery in Ni and Cu abundances with height in the lava column. Comparison with Noril'sk suggests that although significant quantities of metals were scavenged by sulphides in West Greenland, the metal contents of the sulphides may not have been upgraded by continued interaction with subsequent magma batches.  相似文献   

A high-resolution TEM-AEM, pH titration, and modeling study of Zn coprecipitation with ferrihydrite     

Stacin Martin  Chen Zhu  Joseph Rule  Robert Ford  Yee Soong 《Geochimica et cosmochimica acta》2005,69(6):1543-1553

Experiments of Zn²⁺ and Fe³⁺ coprecipitation as a function of pH were conducted in the laboratory at ambient temperature and pressure. X-ray diffraction patterns of the coprecipitates show two broad peaks at 0.149 and 0.258 nm, which is consistent with published patterns for pure 2-line ferrihydrite. Zn²⁺ uptake occurred at pH ≥5 while Fe³⁺ precipitation occurred between pH 3 and 4, although both Zn²⁺ and Fe³⁺ were present in the same solution during the entire range of pH titration. High-resolution transmission electron microscopy shows that the coprecipitates are 2 to 6 nm sized single crystalline particles but aggregated to 50 to 400 nm sized clusters. Analytical electron microscopy indicated that the 5% atomic Zn with respect to Fe was homogeneously distributed. No segregated phases were found in the clusters or at single crystal edges, which is consistent with published extended X-ray absorption fine structure (EXAFS) results at similar Zn/(Zn + Fe) ratios. Hence, occlusion and surface precipitation may be excluded as possible coprecipitation mechanisms. The bulk solution Zn²⁺ sorption edge was fitted to both solid solution and generalized diffuse layer surface complexation models. However, a solid solution model is inconsistent with published EXAFS results that show tetrahedral polydentate Zn²⁺ complexes sharing apices with Fe³⁺octahedra.  相似文献   

Bridging the climate information gap: a framework for engaging knowledge brokers and decision makers in state climate assessments     

Gillian L. Galford  Julie Nash  Alan K. Betts  Sam Carlson  Sarah Ford  Ann Hoogenboom  Deborah Markowitz  Andrew Nash  Elizabeth Palchak  Sarah Pears  Kristen L. Underwood 《Climatic change》2016,138(3-4):383-395

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Adaptation and Indigenous peoples in the United Nations Framework Convention on Climate Change     

James Ford  Michelle Maillet  Vincent Pouliot  Thomas Meredith  Alicia Cavanaugh  IHACC Research Team 《Climatic change》2016,139(3-4):429-443

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A Comparative Analysis of Weights of Evidence,Evidential Belief Functions,and Fuzzy Logic for Mineral Potential Mapping Using Incomplete Data at the Scale of Investigation     

Arianne Ford  John M. Miller  Augusto G. Mol 《Natural Resources Research》2016,25(1):19-33

Large amounts of digital data must be analyzed and integrated to generate mineral potential maps, which can be used for exploration targeting. The quality of the mineral potential maps is dependent on the quality of the data used as inputs, with higher quality inputs producing higher quality outputs. In mineral exploration, particularly in regions with little to no exploration history, datasets are often incomplete at the scale of investigation with data missing due to incomplete mapping or the unavailability of data over certain areas. It is not always clear that datasets are incomplete, and this study examines how mineral potential mapping results may differ in this context. Different methods of mineral potential mapping provide different ways of dealing with analyzing and integrating incomplete data. This study examines the weights of evidence (WofE), evidential belief function and fuzzy logic methods of mineral potential mapping using incomplete data from the Carajás mineral province, Brazil to target for orogenic gold mineralization. Results demonstrate that WofE is the best one able to predict the location of known mineralization within the study area when either complete or unacknowledged incomplete data are used. It is suggested that this is due to the use of Bayes’ rule, which can account for “missing data.” The results indicate the effectiveness of WofE for mineral potential mapping with incomplete data.  相似文献