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Sydney Harbour is surrounded by a large capital city of about four million people and its highly urbanised (86%) catchment supports a substantial industrial base and an extensive transport infrastructure. Large commercial and naval ports occupy the waterway and the harbour is an important recreational area. Surficial sediment in Sydney Harbour contains high concentrations of PCBs, HCB, total chlordane, total DDT, aldrin, dieldrin, heptachlor and heptachlor‐epoxide, but low concentrations of lindane. PCBs, total chlordane, and to a lesser extent dieldrin, are most elevated in sediment in creeks on the southern shores of the harbour suggesting sources within older, highly urbanised/industrialised catchments of western‐central Sydney. There are high concentrations of total DDT and HCB in sediments of the upper harbour and Homebush Bay suggesting that chemical industries on the shores of the estuary in this area are sources of these contaminants. Although no sediment quality guidelines apply in Australia, empirically derived biological effects criteria suggest that sediment over extensive areas of Sydney Harbour may have an adverse impact on biota. Especially of concern are sediments containing high concentrations of chlordane and DDT. 相似文献
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Kenneth L. Pierce Daniel R. Muhs Shannon A. Mahan Joseph M. Licciardi 《Quaternary Research》2011,76(1):119-141
Loess accumulated on a Bull Lake outwash terrace of Marine Oxygen Isotope Stage 6 (MIS 6) age in southern Jackson Hole, Wyoming. The 9 m section displays eight intervals of loess deposition (Loess 1 to Loess 8, oldest), each followed by soil development. Our age-depth model is constrained by thermoluminescence, meteoric 10Be accumulation in soils, and cosmogenic 10Be surface exposure ages. We use particle size, geochemical, mineral-magnetic, and clay mineralogical data to interpret loess sources and pedogenesis. Deposition of MIS 6 loess was followed by a tripartite soil/thin loess complex (Soils 8, 7, and 6) apparently reflecting the large climatic oscillations of MIS 5. Soil 8 (MIS 5e) shows the strongest development. Loess 5 accumulated during a glacial interval (~ 76-69 ka; MIS 4) followed by soil development under conditions wetter and probably colder than present. Deposition of thick Loess 3 (~ 43-51 ka, MIS 3) was followed by soil development comparable with that observed in Soil 1. Loess 1 (MIS 2) accumulated during the Pinedale glaciation and was followed by development of Soil 1 under a semiarid climate. This record of alternating loess deposition and soil development is compatible with the history of Yellowstone vegetation and the glacial flour record from the Sierra Nevada. 相似文献
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Willie Jamaal Wright 《The Professional geographer》2019,71(1):172-178
This article is a discussion and critique of public intellectualism in the present. Rather than reify a self-aggrandized form of public intellectualism within academia that centers individualized intellectual development and that encourages a greater flow of findings outward to communities, I highlight black women public intellectuals who have used their skills, talents, and station within the university and society in novel ways. Moreover, I suggest that scholars take seriously the questions, research methods, and analyses emerging from the general public, particularly from within communal and political organizations. These encouragements are illustrated by highlighting three political education workshops that have been developed across the United States. 相似文献
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《The Professional geographer》1985,37(1):104-132
Books Reviewed in this article: Lob Trees in the Wilderness . Clifford and Isabel Ahlgren . Satellite Microwave Remote Sensing . T. D. Allan , ed. Sunbelt Cities: Politics and Growth Since World War II . Richard M. Bernard and Bradley R. Rice , eds. Legacy of Minneapolis: Preservation Amid Change . John R. Borchert , David Gebhard , David Lanegran , and Judith A. Martin . Bloomington, MN: Preparing a Historic Preservation Ordinance. Richard J. Roddewig . The Mountains of Northeastern Tasmania, A Study of Alpine Geomorphology . Nel Caine . Introductory Cartography . John Campbell . Englewood Cliffs, NJ: Changing Climate . Manual of Remote Sensing, Second Edition . 2 Vols. Robert N. Colwell , ed.-in-chief; David S. Simonett and John E. Estes , vol. eds. Remote Sensing in Meteorology, Oceanography and Hydrology . A. P. Cracknell , ed. Multidimensional Scaling . Mark L. Davison . Environmental Karst . Percy H. Dougherty , ed. The Urban Environment . Ian Douglas . Geomorphology of Europe . Clifford Embleton , ed. An Introduction to South Asia . B. H. Farmer . Great Geological Controversies . A. Hallam . Hazardous Waste Management: In Whose Backyard? Michalann Harthill , ed. Energy for Subsistence . Margaret Haswell . Perspective on Ratzel's Political Geography . James M. Hunter . Economic Deposits and their Tectonic Setting . Charles S. Hutchison . Energy Risk Assessment . Herbert Inhaber . Discovering the Vernacular Landscape . John Brinckerhoff Jackson . Climate and Energy Systems: A Review of Their Interactions . Jill Jäger . Dilemmas in Regional Policy . Antoni Kuklinski and J. G. Lambooy , eds. California Farmland: A History of Large Agricultural Landholdings . Ellen Liebman . The Spatial Organization of New Land Settlement in Latin America . Jacob O. Maos . Dark Continent: Africa as Seen by Americans . Michael McCarthy . Westport, CT: Climatology: An Introduction . John E. Oliver and John J. Hidore . Columbus, OH: The Geography of Warfare . Patrick O'Sullivan and Jesse W. Miller . The Expanding City. Essays in Honour of Professor Jean Gottmann . John Patten , ed. Scotland's Environment During the Last 30,000 Years . Robert J. Price . Integrated Urban Models . S. H. Putman . Development and the Environmental Crisis: Red or Green Alternatives? Michael Redclift . 相似文献
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PATRICIA NELSON LIMERICK 《Geographical review》1998,88(4):483-491
ABSTRACT. Adopting the persona of the nonacademic, J. B. Jackson was, nonetheless, a major influence on academic scholarship. Expertly and deftly, he played on his understanding of scholarly convention, pushing the boundaries of “legitimate” generalization and assertion. Careful observation of his style reveals eight strategies for testing, mocking, and challenging habits of mind that can unnecessarily constrict scholarly inquiry. From daring in the drawing of conclusions to the wily use of the pronoun “we,” from a refusal to defer to middle-class values to the baiting of environmentalists, Jackson at once had a good time and called much of academic propriety into question. An examination of his “game plan” gives scholars a chance to examine their own habitual practices. 相似文献
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PAUL F. STARRS 《Geographical review》1998,88(4):492-506
ABSTRACT. Academic geography is dotted with fly-specks from the fashion conscious who have skittered from one enthusiasm to another like aggravating bugs in midroom flight. Our disciplinary history in fact abounds in dead-end roads entered at fatally high speed, theoretical turns not negotiated, crossroads oracles proved dismally inaccurate. By contrast, the formidable cultural geographer and landscape historian J. B. “Brinck” Jackson (1909–1996) conceived of a more slowly developing world, replete with enduring geographies. Although firmly Brahmin by origin, Jackson was chary of the fleeting fashions and power tropes of what he sometimes dubbed the Establishment. He was inclined instead to attend to the structures of the everyday, emphasizing community and connection over didactic fashion. With writing grounded in daily experience and a consummate ability to witness pattern, he urged geographers to think and envision. 相似文献
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Lynette C. McLoughlin 《The Australian geographer》2000,31(2):183-208
Described by Governor Phillip as 'the finest harbour in the world', Sydney Harbour was affected by accelerated sedimentation very soon after settlement in 1788. Dredging began in 1842 to deal with the problems caused by sedimentation and to enhance foreshore amenity. By the end of the nineteenth century, dredging was also excavating the bottom of the Harbour and its bays to accommodate larger ships with deeper draughts, and dredged sediment was increasingly used to reclaim mudflats or marshes deemed unhealthy or unsightly, thereby creating additional useful waterfront land. There was virtually continuous dredging in some part or other of the Harbour and its tributaries for almost 140 years. With increasing costs and mounting environmental concerns, dredging is now intermittent, and carried out largely to facilitate navigation for specific projects, despite continued sedimentation. While there was an early lack of understanding of the Australian environment and the impact of clearing on soils, the causes of increased sedimentation had been documented by the 1860s. However, measures to seriously address causes were not introduced until late in the twentieth century. This paper briefly outlines the development of the Sydney estuary to 1788, considers the impact of settlement in accelerating sedimentation, traces the development of dredging and reclamation, and discusses their significance for a number of areas of current research and environmental management, as well as to social and economic history. Within the limitations of the data available, annual sediment dredged, annual expenditure, cost per tonne, and areas reclaimed by dredging and filling are included. 相似文献
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Concentrations of polychlorinated dibenzo-p-dioxins (dioxins)(PCDDs) and polychlorinated dibenzofurans (PCDFs)(furans) in sediments from Port Jackson ranged from 32 to 4352 pg WHO-TEQ DF g(-1)dw with a mean of 712 pg g(-1)dw. Maximum total dioxins plus furans concentrations in this sediment was 6,290,000 pg g(-1)dw, which is the highest recorded in Australia and among the highest reported for sediment globally. Permanent bans were placed on fin fishing and prawn trawling in February, 2006 for the whole estuary, based on dioxin tissue burdens. A distinct congener profile corresponded to chemicals known to have been produced by industry on the shores of Homebush Bay in the upper estuary. These chemicals are being dispersed extensively and exceed pre-anthropogenic concentrations in even distant, less developed parts of the harbour. Remediation of sediments is currently being undertaken, with the intention of containing dispersion of dioxins and reducing body burdens in fin fish and prawn populations. 相似文献
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William F. Kenney Matthew N. Waters Claire L. Schelske Mark Brenner 《Journal of Paleolimnology》2002,27(3):367-377
Primary producer community structure (PPCS) in shallow lakes isinfluenced by phosphorus (P) load and water column P concentration.Theoretically PPCS may shift between phytoplankton and macrophyte states withintermediate P loading, but phytoplankton dominate when P loading exceeds acritical threshold. We analyzed sediment cores from five shallow, eutrophiclakes (size range: 0.6 to 125 km2) that arephytoplankton dominated to determine whether the development of the currentstate was associated stratigraphically with an increase in sediment total P(TP) and a shift in PPCS. We used sponge biogenic silica(BSiSponges) concentrations and total carbon to total nitrogenratios (TC:TN) as proxies for macrophyte abundance and sediment organic mattersource, respectively. Three stratigraphic groups of sediments were identifiedwith k-means cluster analysis. These samples were grouped by increasing TPconcentrations and decreasing age and identified as macrophyte, transitionaland phytoplankton sediments. Results show that as P loading increased in thelate 19th and early 20th centuries, the lakes producedsediments with an increasing contribution from phytoplankton. Four of our lakesmay represent a subset of shallow lakes because of their large size (30 to 125km2) and relatively rapid historic P enrichment. Inthese Florida lakes, PPCS shifted to phytoplankton dominance with nopaleolimnological record of lake-wide alternating stable states or of lake-widephytoplankton dominance before anthropogenic P enrichment. 相似文献