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271.
Otolith increment age estimates for a deepwater species, Allocyttus verrucosus, were validated by comparison with the results from 210Pb:226Ra radiometric analysis. Transverse sectioning and subsequent grinding of otoliths to a thickness of 0.2 mm revealed increments which provided age estimates for a range of fish sizes. Age estimates ranged from 7 yr for an immature fish of 15.2 cm total length (TL) to 130 yr for a female fish of 36.5 cm TL. Age at maturity was estimated as 28 yr for females and 24 yr for males. In comparison, radiometric analysis of whole otoliths, using a single linear otolith-mass growth-rate model suggested maximum ages of 130 to 170 yr for fish of 34 to 35 cm TL. Radiometric ages were also recalculated using a two-phase otolith-mass growth-rate model in which the growth rate was assumed to slow after maturity to 90% of the pre-maturity rate. This reduced the maximum age to 132±15 yr for a mean fish length of 34.5 cm. Age at maturity for females was estimated at 34 yr. The similarity between age estimates from otolith-increment counts and radiometric analysis strongly supports the accuracy of results from both methods, and encourages further use of such comparisons as an alternative to traditional validation techniques.  相似文献   
272.
A mass synchronous spawning of the sea urchin Evechinus chloroticus (Valenciennes) was observed in situ in Doubtful Sound, a large New Zealand fiord. Spawning occurred between 17:30 hrs and 18:30 hrs on 27 January 1994 and coincided with a full moon, spring tides and a period of decreasing sea temperatures. During spawning, the sea urchins formed a dense spawning aggregation of both sexes, with >90% of the urchins observed spawning at the time. Spawned gametes clouded the water column, and some were eaten by small labrid fish species. The spawning, which may have been as widespread as 40 km, marked a 42 to 50% decrease in gonad indices and resulted in a widespread, dense cohort of  E. chloroticus larvae within the fiord. Received: 25 September 1997 / Accepted: 6 March 1998  相似文献   
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Phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy has become popular for the characterization of P species in environmental samples. However, these are commonly made alkaline (pH?>?13) to facilitate sample comparison and ease peak identification, but this may cause hydrolysis of some compounds. This study examined the chemical shift of known P compounds and supplemented this with published data to determine the viability of examining samples at their native pH, thereby minimizing sample disturbance. A 31P NMR pH titration of known P compounds resulted in chemical shifts ranging from about ?22 to 8 ppm in the pH range 5–13. Categorization and calculation of chemical shifts for over 100 naturally occurring compounds indicated that good distinction between orthophosphate diesters, orthophosphate monoesters, nucleotides, phosphonates, and phosphagens was best at ≥pH 7, but unlikely below this pH. Analysis of several water extracts of soil and dung, overland flow samples, and lake water indicated a wide variety of well-defined peaks that were assigned to orthophosphate, orthophosphate monoesters, orthophosphate diesters, pyrophosphate, polyphosphate, or phosphonates. Changing the sample pH to >13 caused many species (such as phosphonates, orthophosphate diesters, and polyphosphates) to decrease either by hydrolysis or precipitation. Hence, it is recommended that samples be analysed at their native pH but, if poorly resolved, should have their pH raised to ≥7.  相似文献   
276.
Tailfat samples were collected from 56 platypuses, 38 male and 18 female in Tasmania. No statistically significant, nor apparent, differences between the sexes were found for tailfat lipid levels and DDT and its metabolites. Lindane and PCB concentrations in tailfat lipid. Apparently--but not statistically--significantly different levels of DDT and its metabolites. Lindane and PCB concentrations were found in animals from different geographic regions of the State. Higher concentrations of DDT and its metabolites and Lindane were related to the intensity of agricultural activity and elevated PCB levels were mainly found in animals from zones with industrial and hydroelectric developments.  相似文献   
277.
Powell BA  Mercer SW  Harte C 《Disasters》2002,26(2):175-191
The present study aimed to measure the quality of life (QOL) of disabled people in Cambodia and the impact of rehabilitation services. The categories of services were: physical rehabilitation (prosthetics/orthotics with physiotherapy); community-based rehabilitation; and (3) labour market assistance. The 164 respondents were from a range of urban and rural settings. The results suggest that QOL was substantially lower among disabled Cambodians who had received no rehabilitation services compared to those who had received one of the three categories of rehabilitation services. QOL scores tended to be highest, however, among those who had received a combination of all three services. The results also highlighted the vulnerability of certain sub-groups who may need specific provision in planning, policy-making and service delivery. The present study suggests that an integrated approach may be the best way to maximise the impact of individual rehabilitation services in Cambodia.  相似文献   
278.
This study examines the use of spatial optimization techniques for multi-site land-use allocation problems (MLUA). 'Multi-site' refers to the problem of allocating more than one land-use type in an area, which are difficult problems as they involve multiple stakeholders with conflicting goals and objectives. Spatial optimization methods consist of (1) an optimization model and (2) an algorithm to solve the model. This study demonstrates a goal-programming model to solve the MLUA problem. The model is solved using both simulated annealing and genetic algorithms. Special attention has been given to introduce a spatial compactness objective in the model. It is shown that the compactness objectives in the optimization model generate compact patches of the same land use for using both the simulated annealing procedure and the genetic algorithm. In addition, it appears that using the proper settings of the compactness objectives, connectivity between patches of land use is promoted. The method is tested for a fictive study and then demonstrated for a real case study, both measuring 20 × 20 cells. The genetic algorithm generally performs better than simulated annealing in terms of solution time and achieving compactness.  相似文献   
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Book reviews     
Traffic Mix Model

(TRRU Research Report No. 30).

A Methodology for Estimating Recreation Traffic Flows.

August 1977, University of Edinburgh. 144 pps.

“Recreation in the Highlands and Islands”

Tourism and Recreation Research Unit, University of Edinburgh, December 1976.

Research Report No. 22, 411pp with tables and diagrame; Research Report No. 31, 145 with tables and diagrams.

Tourism and Recreation in the Chichester Area: a basis for planning

Tourism and Recreation Research Unit, Research Report No. 35, University of Edinburgh.

The Real Wealth of Nations

S. R. Eyre

Arnold, London, 1978. £7.95.

Landscape Construction

M. F. Downing

E. & F. N. Spon, London, 1977

Planning and Organizing for Social Change. Action Principles from Social Science Research.

Jack Rothman

Columbia University Press. 628 p.p.

Models and Cities and Regions

A. G. Wilson, P. H. Rees, C. M. Leigh (editors) 1977

Wiley, £12.75.

Ecology and Ekistics

C. A. Doxiadis Edited by Gerald Dix

Paul Elek, London 1977. Environmental Studies Series. 91 p.p. Paperback. £3.75.

Tackling Urban Deprivation : The Contribution of Area‐Based Management

T. Mason, K. Spencer, C. Vielba and B. Webster

Institute of Local Government Studies, University of Birmingham, Dec. 1977. 93p.p. No price stated.

Marketing Geography : with special reference to retailing

R. L. Davies

Methuen, 1976. £3.45.

“Public Participation in Planning”

Edited by W. R. D. Sewell and J. T. Coppock

J. Wiley & Sons Ltd., Chichester, 1977. 208 p.p. £9.00.

“The Individual Citizen and Public Participation”

William Hampton and Raymond Walker

Linked Research Project into Structure Planning, Interim Research Paper. 13, 1978. 24 p.p. £1.00.

A Future for Planning Science Fiction Cities

Town Planning discussion paper No. 27. Stephen Wood

U.C.L. 1977.

“The Bicycle Planning Book “

Mike Hudson (editor)

Open Books Publishing Ltd. and Friends of the Earth, 1978. Paperback, £1.95.

Residential Location and Urban Housing Markets

G. K. Ingram (1977) (ed.)

Cambridge, Mass : Ballinger Publishing Co., for the National Bureau of Economic Research.  相似文献   

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