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Jai Vaze Paul Barnett Geoffrey Beale Warrick Dawes Ray Evans Narendra Kumar Tuteja Brian Murphy Guy Geeves Michelle Miller 《水文研究》2004,18(9):1613-1637
A comprehensive framework for the assessment of water and salt balance for large catchments affected by dryland salinity is applied to the Boorowa River catchment (1550 km2), located in south‐eastern Australia. The framework comprised two models, each focusing on a different aspect and operating on a different scale. A quasi‐physical semi‐distributed model CATSALT was used to estimate runoff and salt fluxes from different source areas within the catchment. The effects of land use, climate, topography, soils and geology are included. A groundwater model FLOWTUBE was used to estimate the long‐term effects of land‐use change on groundwater discharge. Unlike conventional salinity studies that focus on groundwater alone, this study makes use of a new approach to explore surface and groundwater interactions with salt stores and the stream. Land‐use change scenarios based on increased perennial pasture and tree‐cover content of the vegetation, aimed at high leakage and saline discharge areas, are investigated. Likely downstream impacts of the reduction in flow and salt export are estimated. The water balance model was able to simulate both the daily observed stream flow and salt load at the catchment outlet for high and low flow conditions satisfactorily. Mean leakage rate of about 23·2 mm year?1 under current land use for the Boorowa catchment was estimated. The corresponding mean runoff and salt export from the catchment were 89 382 ML year?1 and 38 938 t year?1, respectively. Investigation of various land‐use change scenarios indicates that changing annual pastures and cropping areas to perennial pastures is not likely to result in substantial improvement of water quality in the Boorowa River. A land‐use change of about 20% tree‐cover, specifically targeting high recharge and the saline discharge areas, would be needed to decrease stream salinity by 150 µS cm?1 from its current level. Stream salinity reductions of about 20 µS cm?1 in the main Lachlan River downstream of the confluence of the Boorowa River is predicted. The FLOWTUBE modelling within the Boorowa River catchment indicated that discharge areas under increased recharge conditions could re‐equilibrate in around 20 years for the catchment, and around 15 years for individual hillslopes. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Movement patterns of individual migrating western rock lobster,Panulirus cygnus,in Western Australia
Abstract Migrating and pre‐migrating western rock lobster Panulirus cygnus were tagged with datastorage tags that recorded temperature and pressure, which was converted to depth (Pressure (kPa) — surface pressure (kPa)/10)) at Dongara and Jurien Bay in Western Australia between December 2005 and December 2007. All lobsters were fitted with tag flotation devices, and returns were made by either commercial fishers or beachcombers who located detached tags. A total of 135 lobsters were released with “backpack” flotation tags, but only 84 (62.2%) of the backpacks carried data‐storage tags. Depths of release ranged from 5 to 113 m. Of the tagged lobsters released, commercial fishers recaptured 52 (38.5%), whereas 11 tags (8.1%) were found by beachcombers. At least 33%, and possibly up to 63%, of animals identified by their pale coloration as pre‐migrating individuals, failed to migrate. Those that did migrate (n = 11) were at liberty from 1 to 94 days and showed generally similar movement patterns in that they migrated only at night from darkness (after 2000 h) until after moonrise. However, their movement patterns were less constrained by the rising of the moon in deep water. Only 27% migrated nightly, compared with 73% that skipped migrating on one or more nights, to restart some days later. This latter proportion would likely have been considerably greater, but some migrating animals were only at large for short periods before recapture, and therefore had little time to show any variation to the nocturnal migration pattern. Individual speeds of migration during periods of activity were estimated for nine lobsters as 0.20 to 0.68 km h?1, with a mean speed of 0.44 km h?1, or 7.4 m min?1. Improved knowledge of daily movement patterns resulting from this study provides a potentially important input into technological improvements in bait and pot design. 相似文献
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Current methods for estimating the incidence and prevalence of non‐legal drug use tend to be retrospective and are not capable of forecasting spatial characteristics. This paper details the development of a GIS model for forecasting and displaying spatio‐temporal trends in non‐legal drug use. It builds upon a current model that estimates levels of drug use, using GIS to develop and visualise the spatial dimension and to predict levels of use for unknown locations using radial basis functions with a thin spline interpolator. The model is calibrated against known data for the onset and spread of heroin use. Results of validation and cross validation of the interpolated surfaces give some confidence to the accuracy of the method. It provides a first stage in a process to develop more complex models that might be used to examine the introduction of new drug use practices, socio‐economic characteristics of different drug use habits, harm reduction measures or to further examine the role of space in the spread of drug use. 相似文献
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Access and mobility are important dimensions of quality of life. For wheelchair users, everyday trips are often fraught with problems, with many barriers imperceptible to the able-bodied, hindering or totally restricting movement. This paper describes a project undertaken with wheelchair users, which has developed, tested and applied a Geographic Information System model. This model acts both as a navigational device for wheelchairs users – enabling them to make informed route choices through urban places – and as a decision support and planning tool for urban planners – making visible the ways in which built environments are often distorted and hostile spaces for wheelchair users. 相似文献
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Jacquez Geoffrey M. Essex Aleksander Curtis Andrew Kohler Betsy Sherman Recinda El Emam Khaled Shi Chen Kaufmann Andy Beale Linda Cusick Thomas Goldberg Daniel Goovaerts Pierre 《Journal of Geographical Systems》2017,19(3):197-220
Journal of Geographical Systems - As the volume, accuracy and precision of digital geographic information have increased, concerns regarding individual privacy and confidentiality have come to the... 相似文献
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This paper develops a reading of the wardrobe which emphasises the wardrobe's location within the consumption practices of tidying, sorting and the displacement of clothing. Its emphasis is on the circulation of clothing matter and the transience of clothing consumption, not––as recent accounts have stressed––the accumulation, collection and wearing of clothing. Using primarily the example of maternity wear, the paper outlines how clothing matter circulates amongst and between women (between siblings, between friends and amongst neighbours and acquaintances) and accounts for this practice. It argues that maternity wear circulation is both an embodied divestment/recovery ritual and about the making of mothers, through its appeal to thrift, sacrifice and making-do. The paper concludes by reflecting on the significance of the absence of maternity wear from women's wardrobes and by suggesting that wardrobes need to be thought of not just as containers of memory, but as temporary holding places in the lives of clothes, and as pivotally positioned as a fulcrum for clothing movement, between wearing, storage and displacement. 相似文献
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Le Bas T.P. Somers M.L. Campbell J.M. Beale R. 《Oceanic Engineering, IEEE Journal of》1996,21(4):545-553
For many years, GLORIA has been producing sonar images of the deep ocean floor. In the mid-1980's, the SeaMARC II system came to prominence producing depth values as well as sonar images. The basic method compares the phases of the signals returning from the seafloor to two rows of transducers. The phase differences are converted into angles of arrival and together with the arrival times converted into range and depth values. This capability has now been added to the GLORIA system. The fact that GLORIA uses a 2s FM pulse means the backscattered reverberation can come from a strip of seafloor up to 1.5 km wide. To accommodate this, overlapping complex FFT's are used to produce a time-frequency matrix for the returning signals. In this matrix, a constant range feature appears as a diagonal. Phases are then calculated using a least-mean-squares estimate along diagonals. The main source of error and bias is due to surface reflection, and this is taken into account. The GLORIA swath bathymetry system was tested on two cruises and it was possible to produce depth contours with a good level of confidence. The total swath width was over eight water depths and would have been greater with a more favorable velocity profile. Comparison with other bathymetry data (such as multibeam systems) showed excellent correlation, having a standard deviation of only 4% of total water depth 相似文献
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