Data Analysis Australia Pty Ltd

Nedlands, Australia

Data Analysis Australia Pty Ltd

Nedlands, Australia
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Chapman T.F.,Bentley Delivery Center | Chapman T.F.,Data Analysis Australia Pty Ltd | McCaw W.L.,Locked Bag
Pacific Conservation Biology | Year: 2017

The aim of this study was to quantify the relative effort for biodiversity surveys across the public forest estate in the south-west of Western Australia. We collated information on historical surveys into a metadatabase and recorded locations where surveys had been conducted in a spatial geodatabase. We then used multicriteria modelling to rank land conservation units on the basis of relative survey effort. The results indicated that the western, particularly the south-western, parts of the study area were relatively well surveyed while eastern parts were relatively poorly surveyed. This is likely to reflect greater habitat loss and fragmentation of vegetation on the eastern margins of the forest estate where it adjoins the extensively cleared Western Australian wheatbelt. There was also an emphasis on monitoring biodiversity in forest habitats closer to the main population centres of the south-west. The results of this analysis provide a basis for assessing future survey needs for the region, which should also consider: patterns of distribution in species richness; the extent, connectivity and conservation status of native vegetation; and the relative risks posed to biodiversity by infrastructure and industrial land uses. We discuss the potential limitations of the multicriteria modelling approach in the context of our study. © CSIRO 2017.

Milne A.E.,Rothamsted Research | Haskard K.A.,Data Analysis Australia Pty Ltd | Webster C.P.,Rothamsted Research | Truan I.A.,Rothamsted Research | And 2 more authors.
Journal of Environmental Quality | Year: 2013

We analyzed data on nitrous oxide emissions and on soil properties that were collected on a 7.5-km transect across an agricultural landscape in eastern England using the discrete wavelet packet transform. We identified a wavelet packet "best basis" for the emission data. Wavelet packet basis functions are used to decompose the data into a set of coefficients that represent the variation in the data at different spatial frequencies and locations. The "best basis" for a set of data is adapted to the variability in the data by ensuring that the spatial resolution of local features is good at those spatial frequencies where variation is particularly intermittent. The best basis was shown to be adapted to represent such intermittent variation, most markedly at wavelengths of 100 m or less. Variation at these wavelengths was shown to be correlated particularly with chemical properties of the soil, such as nitrate content. Variation at larger wavelengths showed less evidence of intermittency and was found to be correlated with soil chemical and physical constraints on emission rates. In addition to frequency-dependent intermittent variation, it was found that the variance of emission rates at some wavelengths changed at particular locations along the transect. One factor causing this appeared to be contrasts in parent material. The complex variation in emission rates identified by these analyses has implications for how emission rates are estimated ©American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

Manning R.,Western Australian Department of Agriculture and Food | Sakai H.,Data Analysis Australia Pty Ltd | Eaton L.,Data Analysis Australia Pty Ltd
Australian Journal of Entomology | Year: 2010

Langstroth hives fitted with a modified lid with an entrance lined with soft felt or steel or plastic pollen traps or hives fitted with plastic pollen traps and sugar-fed significantly increased the pollen count on the bodies of exiting honey bees. In terms of utilising the research findings in contract pollination service where costs can determine profitability, the recommendation is for a trial in a commercial orchard (e.g. almond, apple, avocado, plum) of sugar-fed single hives fitted with plastic pollen traps. Despite the bees' destruction of the felts lining the modified lid entrances, the soft felt liner might be a worthwhile inclusion into any field trial. © 2010 The Authors. Journal compilation © 2010 Australian Entomological Society.

Whitford K.R.,Science Division | Stoneman G.,Sustainable Forest Management Division | Seymour A.,Forest Products Commission | Murray P.,Forest Management Branch | And 2 more authors.
Australian Forestry | Year: 2012

Timber harvesting with heavy machinery can cause long-lasting compaction of forest soils, adversely affecting soil processes such as infiltration and respiration that are fundamental to forest health. This study examined the effectiveness of corduroying as a means of reducing soil compaction on log extraction tracks during timber harvesting under moist soil conditions in the forests of south-western Western Australia. The effects of the weight of logs removed from the stand, soil gravel content and initial bulk density, were also considered. Timber harvesting under moist soil conditions lead to significant compaction of surface soil on primary and secondary extraction tracks. This compaction was significantly related to four factors: timber load, initial soil bulk density and gravel content, and the use of cording. Compaction increased as the total load of timber hauled over the tracks increased. Soils with a high initial bulk density were less compacted during timber harvesting than soils with a low initial bulk density. On soils with initial bulk densities greater than about 0.55 g cm-3, compaction decreased as gravel content of the soil increased. Cording also significantly reduced soil compaction, but this reduction was small and may not justify the cost or the associated negative environmental impacts of routinely using corduroying while harvesting timber on moist soil. While reducing the load of timber hauled over an extraction track reduces soil compaction, this does not provide a practical solution for reducing soil damage in timber harvesting. Rather than dispersing traffic across many extraction tracks to reduce the load on individual tracks, the impact of soil compaction is best minimised by focusing all traffic onto as few tracks as possible; thus minimising the area of forest soil that is compacted by harvesting machinery. In addition, reusing compacted extraction tracks that remain from any previous harvesting is one of the most effective means of reducing the impact of timber harvesting on forest soils.

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