School of Agriculture, Food and Ecosystem Sciences - Research Publications
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ItemOn assessing some of the net effects of IPM(Australian Agricultural and Resource Economics Society, 1996)The potential costs and benefits, private and external, of a shift to Integrated Pest Management (IPM) are considered. A method is developed to estimate the private net returns of IPM in particular farm situations. This method is then applied to compare the financial characteristics of IPM and conventional systems in apple and grain legume production in Victoria. A key finding is that in a 'typical year' of a 'typical operation' the annual net returns of a shift to IPM, in both crops, could be positive. Externalities associated with IPM may be positive or negative depending on the circumstances.
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ItemAn economic evaluation of alternative pest management strategies in Northern Victorian peach orchards(Australian Agricultural Economics Society, 1994)
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ItemThe tax Australia has to have(Australian Agricultural Economics Society, 1994)
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ItemThe decision to invest in lime for acid soils(Australian Agricultural Economics Society, 1994)This study is about how to make long-term farm management decisions effectively when the amount of information available is extremely limited. Long-term decisions rely on judgements of input responses and outcomes which are uncertain or unknown. This is the reality of farm management decision-making. Complex decisions have to be based, in part, on some very ‘soft’ data. Therefore, good decision-making relies on good judgement. Judgement derives from lessons from experience (old information), and from the assimilation of new information generated by analysis of all the available information. In this study, information about liming acid soils in north-eastern Victoria is used, along with farm management information, to generate further information, and thus facilitate the making of some judgements about the economic merit of investing in lime on a particular farm. Soil acidity is a physical phenomenon which has the potential to lower agricultural production and reduce farm profitability. The potential of soil acidity to lower agricultural production has led to it being described as a serious problem for agricultural activities in south-eastern Australia (Coventry 1985; Coventry et. al. 1987a; Cregan 1980; Ellington 1984b; Evans 1991; Helyar et. al. 1990; Reeves and Ellington 1985; and Williams 1980). Making long-term farm management decisions with the limited information which is available requires finding a way to analyse and assimilate the available and new information, and then presenting it in such a way that sound judgements can be made about the likelihood of the possible outcomes actually eventuating. In this study, the standard farm management investment technique discounted cash flow analysis is used. To facilitate making sound judgements about the likelihood of outcomes, a break-even method is developed and applied to the major unknown parameter. The break-even level of the critical factor in the investment provides the decision-maker, who is looking ahead in a world of very uncertain input responses and outcomes, with something concrete on which to focus. Judgements can be formed about the likelihood of this critical level of the critical variable being achieved. The analysis of liming as an investment provides information on the yields required for an investment in lime on the case study farm to break-even, that is, to cover all costs, including the opportunity cost of capital. The judgement made as to whether such yields are achievable will determine whether liming is a worthwhile investment on the case study farm and, implicitly, whether soil acidity is a problem requiring action by the case study farmer at this stage.
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ItemNo Preview AvailableUsing local knowledge to identify drivers of historic native vegetation change(Modelling and Simulation Society of Australia and New Zealand Inc, 2009-07-17)Research underway with three Catchment Management Authorities in Victoria (Goulburn Broken, North Central and North East) is examining the impacts these bodies have had, and could potentially have, on native vegetation extent and quality (condition) on private land. This paper outlines how local knowledge together with spatial data and ecological information is being used to develop Bayesian Networks (BNs) that show historic changes in native vegetation quality and extent in three regions of northern Victoria since the 1880's. The research is being focused on three case study areas, one located in each partner CMA (Figure 1). Comparison of aerial photography from 1946/7 with contemporary modelled tree canopy cover identified that native vegetation extent has increased or decreased to varying degrees over time and space in each case study areas. Local knowledge elicited from the regional workshops has identified the catalysts of change over time as including episodic events, the viability of the farming industry, demand for 'lifestyle' properties, rabbit control, NRM and Landcare initiatives and policy instruments. Changes in extent and quality of native vegetation varied spatially and temporally across the landscape depending on the presence of remnant native vegetation, land tenure, agronomic potential of the land, historic events (e.g. bushfires), characteristics of the local population and targeted policy instruments. Expansion and intensification of farming between the mid-1950s and the late 1970s was matched by a general decline in the extent of woody native vegetation on private land. A decline in farm profitability from the 1980s to 2006 was associated with declines in farm employment, the number of farmers, population, and businesses and services in small rural towns dependent on agriculture and increases in 'lifestyle' farming around rural towns and regional centres. A general increase in the extent of woody native vegetation on private land was noted over this period by workshop participants. BNs are being used to integrate local knowledge on historic land cover and vegetation change, and its drivers, with analysis of spatial data to capture changes in condition over time (60+ years). The regional workshops have been crucial in developing conceptual understanding of the relationships between external drivers (e.g. climate, market forces), actions (e.g. land clearing, de-stocking, revegetation) and outcomes (e.g. vegetation change). The knowledge and understanding of changes in land use and management and their drivers that was gained from the workshops have been used to refine the influence diagram for the historic vegetation extent and quality BNs, define the details of each variable (e.g. states, key assumptions) and identify key decades to represent in the models.
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ItemNo Preview AvailableRiparian tree water use by eucalyptus coolabah in the Lake Eyre Basin(Conference Organising Committee, 2006)The Lake Eyre Basin (LEB) is characterised by enormous stream flow variability, low rainfall, saline groundwater and at times saline surface water; conditions that demand flexible tree water use strategies in the riparian zone. In the lower reaches of the Diamantina River, the water sources and extraction patterns of Eucalyptus coolabah were examined using isotope data from xylem, soil water, groundwater and surface water. Additionally, soil chloride and matric potential data were used to infer zones of water availability for root uptake. It was found that despite their elevated salinity, groundwater and soil water formed a large proportion of the transpiration flux, with little contribution from standing pools of surface water. At two sites located on the dry floodplain, the data indicated E. coolabah relied substantially on groundwater with a salinity exceeding 30,000 mgL-1Cl. However, some dilution with fresher soil water was evident at most sites, highlighting the importance of flooding in replenishing soil water. Water extraction primarily occurred in the unsaturated zone where a compromise between salinity and source reliability was required. However, E. coolabah was found to have higher salinity tolerances than previously reported for Eucalyptus species.
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ItemDharma as Man : A Myth of Jesus in Buddhist Lands(Uni-Verity Press, 2009)A rendering of the combined Christian gospels into Buddhist concepts and language in a setting consistent with the India of today and 200 years ago.
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ItemTowards the Next Generation of Rural Water Demand Modelling(MODELLING & SIMULATION SOC AUSTRALIA & NEW ZEALAND INC, 2007)
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ItemMicrowave Treatment Accelerates Solar Timber Drying(American Society of Agricultural and Biological Engineers, 2006)
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ItemMicrowave preconditioning to accelerate solar drying of timber(The Microwave Working Group, 2004-12-01)