Thermoluminescenge and Uranium‐Thorium chronologies of pleistocene coastal landforms of the Illawarra region,New South Wales     

E. A. Bryant  R. W. Young  D. M. Price  S. A. Short 《The Australian geographer》1990,21(2):101-112

TL determinations of the ages of aeolian sands and U/Th determinations of the ages of crusts on rock platforms in the Illawarra region, especially at Red Point, indicate that these techniques give considerable promise of a major advance in deciphering the Pleistocene coastal record in Australia. The methods of dating are outlined, and problems of laboratory and field interpretation are considered. The longstanding debate as to whether the +2 m level of platforms is modern or is a Pleistocene relict has been resolved for the Illawarra coast, where these platforms can be shown to have been formed during the Last Interglacial high stand of the sea. By inference, the +4 m level must be of at least the same age. The +6 to 7 m level was cut by about 300Ka and may be as old as Pliocene. Four aeolian units at Red Point reworked from nearby barrier beach complexes date from c. 25Ka, 45Ka, 125Ka, and 300 to >400Ka. Reconnaissance surveys and dating indicate that aeolian sands of similar ages occur elsewhere along the New South Wales coast.  相似文献   

The disturbing case of the concentration of power in human geography     

John Rennie Short 《Area》2002,34(3):323-324

The increasing concentration of power in academic disciplines with the introduction of Research Assessment Exercises is noted. The case of human geography in the UK is discussed.  相似文献   

THE CALIBRATION OF A 35mm NON-METRIC CAMERA AND THE INVESTIGATION OF ITS POTENTIAL USE IN PHOTOGRAMMETRY     

T. Short 《The Photogrammetric Record》1992,14(80):313-322

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The influence of natural variation in discharge on juvenile brown trout population dynamics in a nursery tributary of the Motueka River,New Zealand     

JW Hayes  DA Olsen  J Hay 《新西兰海洋与淡水研究杂志》2013,47(4):247-269

The effects of natural flow variation on juvenile brown trout population dynamics were investigated by biannual sampling over 5.5 years in the Rainy River, a tributary of the Motueka River. A large flood in late March (50-year return period) substantially reduced the density (by 66%) and biomass (by 73%) of 0+ trout over autumn–spring, but the cohort responded with compensatory survival to achieve similar density and biomass by spring as in other years. A low-flow event in February–April (return period >8.4 years), when 7-day low flows fell to 56% of the 7-day mean annual low flow (MALF) and were less than the MALF for 46 days, had no adverse affect on the population. We found no evidence for density-dependent growth. However, there was strong evidence for a two-phase self-thinning response in density, with no self-thinning occurring over summer (i.e. the 0+ population remained below carrying capacity) until a threshold mass of 22.08 g (length=123.7 mm) was attained in autumn after which severe self-thinning took place over autumn to spring. The results indicate that over spring–autumn the population is insensitive to flow reduction and that over autumn–spring the effects of high (and probably low) flow events on local abundance and biomass are offset by compensatory (density-dependent) survival. However, effects on the contribution of migrants to the downstream population remain unknown. The study identified ecological redundancy, which could be exploited for flow allocation. Significantly, it has shown that minimum flows equivalent to the MALF (often advocated by New Zealand conservation and fisheries management organisations) are not always necessary for sustaining juvenile trout populations.  相似文献