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111.
Co-management between local communities and government agencies is promoted as a strategy to improve fisheries management. This paper considers the potential for co-management of sea turtle fisheries within four UK Overseas Territories (OTs) in the Caribbean, and for co-ordinated management among those territories. We focus on fisher incentives for engaging in co-management and on the potential to scale up co-management to a regional level. This paper presents data from Anguilla, British Virgin Islands, Montserrat, and Turks and Caicos Islands, where 110 turtle fishers participated in a socio-economic survey undertaken as part of the ‘Turtles in the UK Overseas Territories in the Caribbean’ project. Based on three established criteria for co-management (perceived crisis in stock, willingness to participate and community cohesion), results suggest that fisher support for co-management exists within each OT, but the extent of support for and views of specific management interventions varies among OTs. The implications of results for co-management in each territory, and for establishing co-ordinated management regimes in the region, are discussed in the context of current debates about the nature of resources and scalar (mis)matches between resource and management regimes.  相似文献   
112.
Diatoms play a significant role in the global carbon cycle through their role in biogenic silica production and the transport of organic matter to the seafloor. Recent work has shown that silicified diatom frustules contain a significant amount of organic matter, and that the proportion of diatom-bound organic matter increases with depth in the water column and sediments. Here, we investigate the association between organic matter and the mineral phase. We used a combination of scanning transmission X-ray microscopy (STXM) and carbon X-ray absorption near-edge structure (XANES) spectroscopy to characterize the distribution and composition of organic matter in frustules of the diatom Cylindrotheca closterium and a biomimetic silica gel. To our knowledge, this study represents the first successful attempt to simultaneously image and obtain chemical information about the organic matter within a diatom frustule using X-ray spectromicroscopy near the carbon edge. Organic carbon, most likely protein, was distributed throughout the frustules and was not removed by harsh chemical treatment. The physical structure of the frustules appeared to be related to the chemical composition of this organic matter, with aromatic or unsaturated carbon being concentrated in the most intricately patterned regions of the frustule. A similar physical and chemical structure was observed in a biomimetic silica gel precipitated spontaneously with polylysine. These results are consistent with the theory that organic constituents of diatom frustules direct silica precipitation and become incorporated within the silica matrix as it forms. The relationship between organic matter composition and silica morphology, the failure of harsh chemical treatments to remove this organic matter, and the spontaneous nature of the co-precipitation of silica and organic matter indicate some chemical interaction between the siliceous and organic components of diatom frustules. Frustule-bound organic matter should therefore be protected from decomposition in the water column or diagenetic alteration in sediments unless the frustule dissolves.  相似文献   
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Book reviews     
GRIFFITH TAYLOR: Antarctic scientist and pioneer geographer (Carleton Library Series No. 145) by M. Sanderson. 15 x 23 cm, xi and 218 pages. Carleton University Press: Ottawa 1988 (ISBN 0 88629 068 6) $C24.95 (hard); (ISBN 0 88629 068 X) $C14.95 (soft) plus postage.

LAND, WATER AND PEOPLE: Geographical essays in Australian resource management edited by R. L. Heathcote and J. A. Mabbutt. 14 x 21 cm, xiii and 266 pages. Allen & Unwin: Sydney 1988 (ISBN 0 04 303008 4) $A24.95 (soft).

ENVIRONMENTAL GEOGRAPHY: Book One by J. Paine, H. McLean and G. Mayhew. 19 x 25 cm, 389 pages. Macmillan: Melbourne 1988 (ISBN 0 333 43073 5) $A28.95 (soft).

Climate Impact Assessment Program (1975) Impacts of climate change on the biosphere, Monograph No. 5, US Department of Transportation, Washington DC.

SMALL‐SCALE AGRICULTURE edited by J. Hirst, J. Overton, B. Allen and Y. Byron. 18 x 25 cm, xii and 210 pages. Commonwealth Geographical Bureau and Department of Human Geography, Australian National University: Canberra 1988 (ISBN 0 7316 3609 0) $A 10.00 (soft).

THE BRITTLE RIM: Finance, Business and the Pacific Region by M. T. Daly and M. I. Logan. 15 × 23 cm, 263 pages, Penguin Books: Ring‐wood 1989 (ISBN 0 14 012095 5) $A24.99 (soft)

THE END OF ORGANISED CAPITALISM by S. Lash and J. Urry. 15 x 23cm, 383 pages. Polity Press: Cambridge 1987 (ISBN 07456 00697) $A34.95 (soft).

THE POLITICS OF DEVELOPMENT: An Introduction to Global Issues by J. L. Seitz. 15 x 23 cm, xiii and 194 pages. Basil Blackwell: New York 1988 (ISBN 0 631 15801 4) $A27.95 (soft).

DEVELOPING WITH FOREIGN INVESTMENT edited by V. Cable and B. Persaud. 16 x 24 cm, viii and 327 pages. Croom Helm: London 1987 (ISBN 0 7099 4825 5) $A87.95 (hard).

PLANNING SYDNEY'S FUTURE by P. Spearritt and C. DeMarco, 21 x 27 cm, and 150 pages. Allen & Unwin: Sydney 1988 (ISBN 0 04 324014 3) $A17.95 (soft).

THE RICHEST LODE: Broken Hill 1888–1988 by R. J. Solomon. 22 x 28 cm, 424 pages. Hale & Iremonger: Sydney 1988 (ISBN 0 86806 333 9).

CONTEMPORARY ISSUES IN DEVELOPMENT (North Australia: Progress and Prospects, Volume 1) edited by D. Wade‐Marshall and P. Loveday. xiii and 310 pages. North Australia Research Unit, Australian National University: Darwin 1988 (ISBN 07315 0335 X).

NEW CALEDONIA OR KANAKY? The Political History of a French Colony (Pacific Research Monograph No. 16) by J. Connell. National Centre for Development Studies, Australian National University: Canberra 1987 (ISBN 0 7315 05123).

DISEASE ECOLOGY by Andrew Learmonth. 15 x 23 cm, 456 pages. Basil Blackwell: Oxford 1988 (ISBN 0 631 15799 9) $A46.00 (soft).

QUALITATIVE METHODS IN HUMAN GEOGRAPHY edited by J. Eyles and D. M. Smith. 15 x 23 cm, xiii and 272 pages. Polity Press: Cambridge 1988 (ISBN 0 7456 0371 8) $A34.95 (soft).

GEOGRAPHICAL SYSTEMS AND SYSTEMS OF GEOGRAPHY: Essays in Honour of William Warntz edited by W. J. Coffey. 14 x 21 cm, 211 pages. Department of Geography, University of Western Ontario: London, Ontario 1988 (ISBN 0 7714 09747) $C30.00 (soft).  相似文献   

115.
Sarah Neal  Sue Walters 《Geoforum》2007,38(2):252-263
Using qualitative data from a research project investigating contemporary rural identities in England this paper examines the apparently contradictory discursive claims that are made on rural spaces. It looks in particular at the ways in which these are narrated - through the notions of rural space as a site of safety, orderliness and community on the one hand and as a site of freedom, anti-order and non-regulation on the other. While the former is a familiar, entrenched and critiqued representation of rurality, the latter narrative has a more marginal and ambivalent place in the dominant rural imaginary. Drawing on Foucault’s concepts of panopticism and heterotopia the paper demonstrates the ways in which the rural is a highly labile concept and emphasises its continual ‘unfinishedness’. However, alongside this, the paper suggests that the tensions and contradictions of the orderly and anti-orderly discourses are underpinned by a particular coherency that is driven by senses of community, belonging and self-regulation. While these do not resolve the contradictions of the discursive claims the potency of such drivers are sufficient to produce a particular inclusive spatiality which is able to accommodate and incorporate the different discursive positions and the practices that are associated with each.  相似文献   
116.
The Western Alps’ active tectonics is characterized by ongoing widespread extension in the highest parts of the belt and transpressive/compressive tectonics along its borders. We examine these contrasting tectonic regimes using a multidisciplinary approach including seismotectonics, numerical modeling, GPS, morphotectonics, fieldwork, and brittle deformation analysis. Extension appears to be the dominant process in the present-day tectonic activity in the Western Alps, affecting its internal areas all along the arc. Shortening, in contrast, is limited to small areas located along at the outer borders of the chain. Strike-slip is observed throughout the Alpine realm and in the foreland. The stress-orientation pattern is radial for σ3 in the inner, extensional zones, and for σ1 in the outer, transcurrent/tranpressional ones. Extensional areas can be correlated with the parts of the belt with the thickest crust. Quantification of seismic strain in tectonically homogeneous areas shows that only 10–20% of the geodesy-documented deformation can be explained by the Alpine seismicity. We propose that, Alpine active tectonics are ruled by isostasy/buoyancy forces rather than the ongoing shortening along the Alpine Europe/Adria collision zone. This interpretation is corroborated by numerical modeling. The Neogene extensional structures in the Alps formed under increasingly brittle conditions. A synthesis of paleostress tensors for the internal parts of the West-Alpine Arc documents major orogen-parallel extension with a continuous change in σ3 directions from ENE–WSW in the Simplon area, to N–S in the Vanoise area and to NNW–SSE in the Briançon area. Minor orogen-perpendicular extension increases from N to S. This second signal correlates with the present-day geodynamics as revealed by focal-plane mechanisms analysis. The orogen-parallel extension could be related to the opening of the Ligurian Sea during the Early-Middle Miocene and to compression/rotation of the Adriatic indenter inducing lateral extrusion.  相似文献   
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Oyster Condition Index (CI) was partitioned, using a moving average filter, into seasonal cycles and long-term trends in the James, York, and Rappahannock rivers for the period 1970–1983. Seasonal cyclic fluctuations in CI could be explained partially by changes in salinity and number of days within various temperature regimes. Long-term trends in the James River show a steady increase in CI over the study period, while a concurrent decline was noted in the Rappahannock River. Superimposed on these trends is a 4 to 5 yr cycle that is in synchrony with river discharge (salinity). In the York River, CI peaked in 1975–1976 at all stations. Measured environmental parameters do not sufficiently explain the trends. We speculate that the differences in the Rappahannock and James rivers may be due to a decline in bottom oxygen as a result of gravitational circulation differences.  相似文献   
120.
This study focuses on the thermodynamics of diagenetic fluid from the Eogene Xingouzui Formation which represents the most important reservoir in Field Oil T in the Jianghan Basin. The measured homogenization temperatures (110–139 °C) of fluid inclusions in diagenetic minerals fell within the range of 67 –155 °C at the middle diagenetic stage. The pressure of diagenetic fluid is estimated at 10.2 –56 MPa. The activity of ions in the fluid shows a tendency of Ca2+ > Mg2+ > Na+ > K+ > Fe3+ > Fe2+ for cations, and HCO 3 > SO 4 2− > F > Cl > CO 3 2− for anions. For the gaseous facies, there is a tendency of CO2> CO> H2S> CH4> H2. According to the thermodynamic calculations, the pH and Eh of the fluid are 5.86–6.47 and −0.73–−0.64V, respectively. As a result of the interaction between such a diagenetic fluid and minerals in the sediments, feldspars were dissolved or alterated by other minerals. The clay mineral kaolinite was instable and hence was replaced by illite and chloritoid. This project was jointly funded by the National Natural Science Foundation of China (49133080) and the Open Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences.  相似文献   
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