Temporal and spatial variability of the sediments budget of the subaerial beach at Warilla, New South Wales

1982 ◽  
Vol 33 (6) ◽  
pp. 945 ◽  
Author(s):  
IG Eliot ◽  
DJ Clarke

A 5-year set of profile data from Warilla Beach, N.S.W., measured fortnightly, has been statistically analysed by using Fourier transform, least-squares, and empirical orthogonal function (eigenfunction or EOF) techniques to identify characteristic patterns of temporal and spatial variation in the sediment volume of the subaerial beach. Least-squares analysis enabled separation of the variation in the subaerial beach at Warilla into a 5-year trend, periodic fluctuations and aperiodic events. The periodic fluctuations are dominated by biennial and annual components. The biennial component accounts for 40% of the sediment budget of the subaerial beach, the annual component 30%, 13% is due to the long-term trend over the 5 years, and about 20% is estimated as aperiodic fluctuations mainly related to changes in the wave regime. Phase differences were identified for periodic oscillations on adjacent beach segments and a chronology of change in sediment volume deduced from the phase differences. The results show that variation in the sediment volume of the subaerial beach is determined by interaction between the biennial and seasonal exchanges although the resulting pattern of exchange may be obscured by higher-frequency beach changes. In alternate years the focus of onshore-offshore sediment exchange shifts from the centre of the beach to the exposed, northern sector. The major depositional zone associated with this exchange is located on the southern+entral sector of the beach and the major erosion zone is on the northern part of the beach. The pattern of alongshore sediment exchange was more closely investigated by EOF analysis. The method facilitated separation of onshore-offshore and alongshore modes of sediment transfer and identification of the patterns of alongshore sediment exchange. The first four EOF's for the data on the subaerial beach at Warilla contain 95.3% of the total variance. The fundamental pattern of sediment movement identified in the EOF analysis involves an onshore-offshore transfer of sediment in biennial, seasonal and 6-monthly cycles. The transfer accounts for 61.7% of the variance for the sediment store of the subaerial beach. The amplitude spectrum of the associated time series for this eigenfunction mode shows that the biennial component is dominant. This result supports the results from the least-squares analysis. It could not have been anticipated from previous studies of beach change from New South Wales or elsewhere and is the subject of ongoing investigation. Subsequent eigenfunction modes identify alongshore movements, with three patterns accounting for a further 33.8% of the remaining variance. They are associated with the prevailing system of inshore water circulation and identify major, recurrent rip and bar locations. Time series associated with the eigenfunction modes confirm the dominance of biennial, annual, and biannual sediment transfers occurring on Warilla Beach.

1978 ◽  
Vol 29 (2) ◽  
pp. 373
Author(s):  
R Barlow ◽  
EB Dettmann

Weaning weight (WW) and conformation score (CS) records on Angus calves from four New South Wales herds were analysed by least-squares procedures. Paternal half-sib components of variance and covariance were used to obtain estimates of heritabilities of various measures of growth and cs, as well as genetic, phenotypic and environmental correlations. Estimates of the heritabilities of measures of growth ranged from 0.20 (all data) to 0.24 when derived from heifer data only. The heritability of cs was 0.24 when the data were adjusted for ww, and 0.19 when no covariate was included in the analysis. All correlations among different measures of growth were positive and close to unity. There were small positive phenotypic and environmental correlations (0.19 to 0.36) and small negative genetic correlations between ww and cs (–0.02 to –0.41).


2009 ◽  
Vol 33 (4) ◽  
pp. 601 ◽  
Author(s):  
Andrew Gibbs ◽  
James E Pearse ◽  
Neill Jones ◽  
Jennifer A Sheehan ◽  
Kathleen T Meleady ◽  
...  

We describe the development of a method for estimating and modelling future demand for sub- and non-acute inpatient activity across New South Wales, Australia to 2016. A time series linear regression equation was used, which is consistent with projection models found in the literature. Results of the modelling indicated an increase in rehabilitation, palliative care and maintenance episodes and bed-days. Projections for other categories of care are problematic due to smaller levels of activity and data quality issues. This project indicated a need for ongoing monitoring of type-changing by facilities and management of data quality. Local planners will need to consider a range of factors when considering the applicability activity projections at a local level, particularly within the specific age and clinical groupings.


Soil Research ◽  
2014 ◽  
Vol 52 (3) ◽  
pp. 253 ◽  
Author(s):  
Xihua Yang

Soil loss due to water erosion, in particular hillslope erosion, can be estimated using predictive models such as the Revised Universal Soil Loss Equation (RUSLE). One of the important and dynamic elements in the RUSLE model is the cover and management factor (C-factor), which represents effects of vegetation canopy and ground cover in reducing soil loss. This study explores the potential for using fractional vegetation cover, rather than traditional green vegetation indices (e.g. NDVI), to estimate C-factor and consequently hillslope erosion hazard across New South Wales (NSW), Australia. Values of the C-factor were estimated from the emerging time-series fractional cover products derived from Moderate Resolution Imaging Spectroradiometer (MODIS). Time-series C-factor and hillslope erosion maps were produced for NSW on monthly and annual bases for a 13-year period from 2000 to 2012 using automated scripts in a geographic information system. The estimated C-factor time-series values were compared with previous study and field measurements in NSW revealing good consistency in both spatial and temporal contexts. Using these time-series maps, the relationship was analysed between ground cover and hillslope erosion and their temporal variation across NSW. Outcomes from this time-series study are being used to assess hillslope erosion hazard, sediment and water quality (particularly after severe bushfires) across NSW at local, catchment and regional scales.


2021 ◽  
Author(s):  
Harry F. Recher

ABSTRACT In Australia’s eucalypt forests and woodlands, co-habiting birds differ in the foraging manoeuvres or methods used to search for and take prey, the substrates and plants on which prey are found, and the heights at which foraging takes place. On the Southern Tablelands of New South Wales, eucalypt forest and woodland birds foraged on different substrates between study plots, seasons, and years. As a result, the proportions of foraging manoeuvres differed in space and time as different foraging methods were used to obtain food from different substrates. Of the 32 species tested for the summer of 1980/81, 24 foraged differently between one or more of the three plots studied. In winter, nine of 15 species on two plots foraged differently between plots. Differences in foraging were found between seasons and/or years for 20 species, including when data from individual plots were combined to test for differences in foraging between summer and winter. Of 70 comparisons of foraging behaviour for individual plots, that is, excluding combined plot data, 50 differed between seasons and/or years. Significant spatial and temporal differences in foraging were recorded for all foraging guilds. Bark and foliage foragers differed most frequently between pairs of plots in all seasons and years, with aerial foragers showing the fewest differences. Between seasons and years differences were greatest among ground-foragers and foliage-foragers where respectively 76% and 80% of intraspecies comparisons on individual plots differed. The differences were the result of temporal and spatial differences in the types and abundances of foraging substrates and the prey available to foraging birds. Each species has its own unique requirements and management targeted at one or a few species will disadvantage others. Consequently temporal and spatial habitat heterogeneity is necessary for the conservation of avian biodiversity.


Sign in / Sign up

Export Citation Format

Share Document