ORCID Profile
0000-0001-7214-4319
Current Organisations
University of the Sunshine Coast
,
John Curtin School of Medical Research
,
NSW Department of Primary Industries
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Publisher: CSIRO Publishing
Date: 2013
DOI: 10.1071/AN11248
Abstract: On the New South Wales Northern Tablelands, sheep, wool and beef cattle production account for most agricultural output. The industries have been challenged in recent years by environmental and economic factors and are therefore looking for modified or alternative livestock management systems that are capable of sustaining profitability. The Cicerone Project aimed to address these issues by comparing three different grazing and pasture improvement systems. Some recent livestock industry analyses have been based on gross margins which do not include overhead costs. This is an important limitation economic analysis needs to report key whole-farm business performance measures since overhead costs can differ significantly between livestock management systems. A representative farm approach was used to compare the profitability of the three different livestock management systems. Commercial-scale whole-farm and cash flow analyses over a 5-year period were used to evaluate profitability. No particular system could be recommended to graziers because the test period was not sufficiently representative of the long-term climate to make an adequate assessment about their long-term profitability. Nevertheless, it is apparent that whole-farm level budgets are essential for comparing the overall profitability of different livestock management systems. It is concluded that analysts, consultants and graziers should use whole-farm and cash flow analyses to gauge profitability of different livestock management systems particularly where sustainability issues are important.
Publisher: CSIRO Publishing
Date: 2013
DOI: 10.1071/AN11249
Abstract: The Cicerone farmlet experiment, conducted on the Northern Tablelands of New South Wales, Australia, explored aspects of profitability and sustainability under three different whole-farmlet management regimes. The 5-year period over which the treatments were measured occurred over a period of generally below-average rainfall, hence responses to management treatments were limited. A modelling approach was used to estimate profitability over a longer period representing the variable climate of the region. A stochastic discounted cash flow model was developed to estimate economic returns of two of the Cicerone management system treatments scaled up from the farmlet scale (53 ha) to the size of a typical commercial farm in the region (920 ha) over a 20-year period. Several scenarios were used to estimate the commercial-scale returns under different rates of pasture improvement and stocking rates. Over the long-term, Farm A was found to be more profitable but also more risky (in terms of variation around the mean of cumulative discounted cash flow) than the ‘typical’ Farm B management system. If livestock managers choose to adopt a pasture improvement strategy based on renovating pastures and increasing soil fertility, they are more likely to achieve higher net worth with more moderate rates of pasture improvement than those explored on Farm A where a high rate of pasture improvement had been implemented in order to quickly differentiate treatments.
Publisher: CSIRO Publishing
Date: 2000
DOI: 10.1071/EA98016
Abstract: Poor persistence of sown pastures, trends of low pasture resowing rates and a substantial decline in carrying capacity of non-crop areas bring into question the basis of the philosophy of pasture improvement by sowing pasture species. If graziers are to adopt grazing strategies or stocking rates that are more ecologically sustainable, then clearly they must also be cost-effective in either increasing income or reducing costs so that they are economically sustainable. This paper describes the use of an interactive spreadsheet model developed to assist graziers and their advisers with assessing the long-term profitability of pasture management and/or improvement (and therefore pasture persistence). The model provides a comparative cash flow for different levels of inputs (fertiliser, herbicides and feed supplements) over a 15-year period. Results clearly show that at the same stocking rate, different animal enterprises have markedly different profitabilities over a 15-year period. Further, for native, improved and sown pastures, the most profitable pastures are those that can sustain increased stocking rates for long periods of time, without the need for resowing.
Publisher: Elsevier BV
Date: 11-2016
DOI: 10.1016/J.JENVMAN.2016.07.039
Abstract: While climate change is confirmed to have serious impacts on agricultural production in many regions worldwide, researchers have proposed various measures that farmers can apply to cope with and adapt to those changes. However, it is often the case that not every adaptation measure would be practical and adoptable in a specific region. Farmers may have their own ways of managing and adapting to climate change that need to be taken into account when considering interventions. This study aimed to engage with farmers to: (1) better understand small-holder knowledge, attitudes and practices in relation to perceived or expected climate change and (2) document cropping practices, climate change perceptions, constraints to crop production, and coping and adaptation options with existing climate variability and expected climate change. This study was conducted in 2015 in Sala Krau village near Pailin (12°52'N, 102°45'E) and Samlout (12°39'N, 102°36'E) of North-West Cambodia. The methods used were a combination of focus group discussions and one-on-one interviews where 132 farming households were randomly selected. We found that farmers were conscious of changes in climate over recent years, and had a good understanding of likely future changes. While farmers are aware of some practices that can be modified to minimize risk and cope with anticipated changes, they are reluctant to apply them. Furthermore there are no government agricultural extension services provided at the village level and farmers have relied on each other and other actors in the value chain network for information to support their decision-making. There is a lack of knowledge of the principles of conservation agriculture that urgently require agricultural extension services in the region to build farmer ability to better cope and adapt to climate change.
Publisher: Elsevier BV
Date: 04-2017
Publisher: CSIRO Publishing
Date: 2008
DOI: 10.1071/SR07077
Abstract: In agricultural systems, soil quality is thought of in terms of productive land that can maintain or increase farm profitability, as well as conserving soil resources so that future farming generations can make a living. Management practices which can modify soil quality include tillage systems and crop rotations. A major proportion of Australian cotton (Gossypium hirsutum L.) is grown on Vertosols (~75%), of which almost 80% is irrigated. These soils have high clay contents (40–80 g/100 g) and strong shrink–swell capacities, but are frequently sodic at depth and prone to deterioration in soil physical quality if incorrectly managed. Due to extensive yield losses caused by widespread deterioration of soil structure and declining fertility associated with tillage, trafficking, and picking under wet conditions during the middle and late 1970s, a major research program was initiated with the objective of developing soil management systems which could improve cotton yields while concurrently ameliorating and maintaining soil structure and fertility. An outcome of this research was the identification of cotton–winter crop sequences sown in a 1 : 1 rotation as being able to sustain lint yields while at the same time maintaining soil physical quality and minimising fertility decline. Consequently, today, a large proportion (~75%) of Australian cotton is grown in rotation with winter cereals such as wheat (Triticum aestivum L.), or legumes such as faba bean (Vicia faba L.). A second phase of research on cotton rotations in Vertosols was initiated during the early 1990s with the main objective of identifying sustainable cotton–rotation crop sequences viz. crop sequences which maintained and improved soil quality, minimised disease incidence, facilitated soil organic carbon sequestration, and maximised economic returns and cotton water use efficiency in the major commercial cotton-growing regions of Australia. The objective of this review was to summarise the key findings of both these phases of Australian research with respect to soil quality and profitability, and identify future areas of for research. Wheat rotation crops under irrigated and dryland conditions and in a range of climates where cotton is grown can improve soil quality indicators such as subsoil structure, salinity, and sodicity under irrigated and dryland conditions, while leguminous crops can increase available nitrogen by fixing atmospheric nitrogen, and by reducing N volatilisation and leaching losses. Soil organic carbon in most locations has decreased with time, although the rate of decrease may be reduced by sowing crop sequences that return about 2 kg/m2.crop cycle of residues to the soil, minimising tillage and optimising N inputs. Although the beneficial effects of soil bio ersity on quality of soil are claimed to be many, except for a few studies on soil macrofauna such as ants, conclusive field-based evidence to demonstrate this has not been forthcoming with respect to cotton rotations. In general, lowest average lint yields per hectare were with cotton monoculture. The cotton–wheat systems generally returned higher average gross margins/ML irrigation water than cotton monoculture and other rotation crops. This indicates that where irrigation water, rather than land, is the limiting resource, cotton–wheat systems would be more profitable. Recently, the addition of vetch (Vicia villosa Roth.) to the cotton–wheat system has further improved average cotton yields and profitability. Profitability of cotton–wheat sequences varies with the relative price of cotton to wheat. In comparison with cotton monoculture, cotton–rotation crop sequences may be more resilient to price increases in fuel and fertiliser due to lower overall input costs. The profitability of cotton–rotation crop sequences such as cotton–wheat, where cotton is not sown in the same field every year, is more resilient to fluctuations in the price of cotton lint, fuel and nitrogen fertiliser. This review identified several issues with respect to cotton–rotation crop sequences where knowledge is lacking or very limited. These are: research into ‘new’ crop rotations comparative soil quality effects of managing rotation crop stubble machinery attachments for managing rotation crop stubble in situ in permanent bed systems the minimum amount of crop stubble which needs to be returned per cropping cycle to increase SOC levels from present values the relative efficacy of C3 and C4 rotation crops in relation to carbon sequestration the interactions between soil bio ersity and soil physical and chemical quality indicators, and cotton yields and the effects of sowing rotation crops after cotton on farm and cotton industry economic indicators such as the economic incentives for adopting new cotton rotations, farm level impacts of research and extension investments, and industry- and community/catchment-wide economic modelling of the impact of cotton research and extension activities.
Publisher: Informa UK Limited
Date: 09-03-2005
Publisher: CSIRO Publishing
Date: 2001
DOI: 10.1071/SR00035
Abstract: Many cotton growers sow rotation crops after irrigated cotton (Gossypium hirsutum L.), assuming that they will improve soil quality and maintain profitability of cotton. Wheat (Triticum aestivum L.) is the most common rotation crop, although more recently, legumes such as faba bean (Vicia Faba L.) and chickpea (Cicer arietinum L.) have come into favour. This paper reports data on soil quality (organic C, nitrate-N, soil structure), yield (cotton lint and rotation crop grain yield, fibre quality), economic returns (gross margins/ha, gross margins/ML irrigation water), and management constraints from an experiment conducted from 1993 to 1998 near Wee Waa, north-western New South Wales, Australia. The soil is a medium-fine, self-mulching, grey Vertosol. The cropping sequences used were cotton followed by N-fertilised wheat (urea at 140 kg N/ha in 1993 120 kg N/ha thereafter), unfertilised wheat, and unfertilised grain legumes (chickpea in 1993 faba bean thereafter), which were either harvested or the grain incorporated during land preparation. Soil organic C in the 0—0.6 m depth was not affected by the rotation crop, although variations occurred between times of s ling. Regression analysis indicated that there had been no net gain or loss of organic C between June 1993 and October 1998. Sowing leguminous rotation crops increased nitrate-N values. A net increase in root-zone nitrate-N reserves occurred with time (from June 1993 to October 1998) with all rotation crops. Soil compaction (measured as specific volume of oven-dried soil) was lower with wheat by October 1998. A net decrease in soil compaction occurred in the surface 0.15 m with all rotation crops between 1993 and 1998, whereas it increased in the 0.15–0.60 m depth. Cotton lint yield and quality, and gross margins/ha and gross margins/ML, were always higher where wheat was sown, with highest gross margins occurring when N fertiliser was applied. Applying N fertiliser to wheat did not significantly increase cotton lint yield and fibre quality, but increased gross margins of the cotton–wheat sequence due to higher wheat yield and protein percentage. Lint yield and fibre quality were decreased by sowing leguminous rotation crops. Management constraints such as lack of effective herbicides, insect damage, harvesting damage, and availability of suitable marketing options were greater with legumes than with wheat. Overall, wheat was a better rotation crop than grain legumes for irrigated cotton.
Publisher: CSIRO Publishing
Date: 2002
DOI: 10.1071/EA00118
Abstract: An experiment was established in 1993 on a sodic Vertosol (Vertisol, Typic Haplustert) at Merah North, north–western New South Wales, to evaluate the sustainability of selected irrigated cotton (Gossypium hirsutum L.)–rotation crop sequences. Crop sequences were selected following discussions with local cotton growers. The indices used to evaluate sustainability included soil quality, microbiology, yield and profitability. This paper presents data on soil properties [soil organic C, structure as air–filled porosity of oven–dried soil, exchangeable Ca, Mg, K and Na, pH, electrical conductivity (EC1:5) and EC1:5/exchangeable Na in the 0–0.6 m depth], lint yield and profitability (as gross margins/ha and gross margins/ML of irrigation water). The 6 cropping systems sown after minimum tillage were: continuous cotton (R1), long–fallow cotton (R2), cotton–green manured faba bean (Vicia faba L.) (R3), cotton–dolichos (Lablab purpureus L.)–green manured faba bean in the first year followed by cotton–wheat (Triticum aestivum L.) (R4), cotton–dolichos (R5), cotton–fertilised dolichos (with P and K removed by cotton replaced as fertiliser) (R6). In 1996, air–filled porosity of oven–dried soil was highest with R4 at the surface but lowest with R1 in the 0.15–0.30 m depth. In subsequent years, air–filled porosity of oven–dried soil was higher with R2 and R4 in the deeper depths, although differences between cropping sequences were small. Air–filled porosity of oven–dried soil increased between 1996 and 1998 in all treatments, and was probably caused by the change from intensive to minimum tillage in 1993, irrigation with moderately saline water and application of gypsum resulting in an increase in EC1:5/exchangeable Na. In general, differences in soil properties such as soil organic C, exchangeable Ca, Mg, K and Na, pH, electrical conductivity (EC1:5) and EC1:5/exchangeable Na between cropping sequences were far less than those which occurred with time. The key changes were decreases in pH, exchangeable sodium percentage, exchangeable cations and organic C between 1994 and 1996, and increases in air–filled porosity of oven–dried soil, EC1:5 and EC1:5/exchangeable Na between 1996 and 1998. A decrease in air–filled porosity of oven–dried soil occurred between 1998 and 1999 as a consequence of preparing land and sowing cotton under very wet conditions. R1 had the highest cumulative gross margin/ha and R3 had the lowest. R2 had the highest cumulative gross margin/ML of irrigation water and R3 again the lowest. Among crop sequences, R2 and R4 gave the best returns with respect to both land and water resources.
Publisher: Springer Science and Business Media LLC
Date: 06-2017
Publisher: CSIRO Publishing
Date: 1999
DOI: 10.1071/SR98109
Abstract: The effects of green manured field pea (Pisum sativum L.), low-input (LI) wheat (Triticum aestivum L.) (seeding rate of 40 kg/ha and 85 kg/ha of diammonium phosphate), and high-input (HI) wheat (seeding rate of 100 kg/ha, 85 kg/ha of diammonium phosphate, and 180 kg/ha of urea) sown as rotation crops after cotton on soil quality cotton growth, yield and nutrient uptake and gross margins ($AU/ha and $AU/ML of irrigation water) were evaluated from 1993 to 1998 in an irrigated Vertosol in the central-west of New South Wales. Soil quality indicators monitored were aggregate stability (dispersion index), compaction (air-filled porosity), soil resilience to structural destruction (as geometric mean diameter of soil aggregates formed after puddling and drying of soil), exchangeable cations, calcium carbonate, nitrate-N, pH, organic C, development of arbuscular mycorrhiza (AM), and incidence of cotton root diseases (black root rot). In comparison with wheat, field pea increased soil nitrate-N levels during the early stages of the experiment and formed smaller aggregates after puddling and drying, but it was ineffective in ameliorating soil compaction. In contrast wheat was very effective in ameliorating soil compaction. Nitrate-N values under wheat–cotton rotations increased with time such that after 4 years they were similar to that under the field pea–cotton rotation. Soil chemical fertility indicators such as organic C, pH, EC, and exchangeable cations were not affected consistently by either wheat or field pea, whereas minimum tillage, retention of crop residues, and cropping phase (i.e. rotation crop or cotton) affected them more. A net decrease in organic C and an increase in EC was observed with time in all treatments. By sowing either field pea or wheat, the mycorrhizal colonisation of cotton roots was improved. Black root rot incidence was increased 3-fold by sowing field pea, but was not significantly affected by wheat. Cotton lint yield was unaffected by rotation crop, although profitability shown as gross margins/ha and gross margins/ML irrigation water were greater with wheat compared with field pea. Gross margins/ha were in the order HI wheat LI wheat field pea, and gross margins/ML irrigation water were in the order LI wheat HI wheat field pea. In terms of ameliorating soil compaction, minimising black root incidence, and maximising returns to the cotton grower, wheat is a better rotation crop than field pea. The decision to apply fertiliser and sow wheat at a higher seeding rate will depend on whether land or water is the major limiting factor.
Start Date: 2009
End Date: 2010
Funder: New Zealand Lotteries Health Research
View Funded ActivityStart Date: 2011
End Date: 2012
Funder: Cancer Society of New Zealand
View Funded ActivityStart Date: 2012
End Date: 2013
Funder: Wellington Medical Research Foundation
View Funded Activity