Field measurements in earth dams

Imperial Users onl

Productivity tradeoffs and synergies for grazing lands in central Queensland to generate carbon offsets

This paper reports research seeking to understand the economic implications for central Queensland graziers of participating in a carbon trading scheme and to measure the likely participation of graziers in an emissions trading scheme under various market design scenarios. An initial desktop study was undertaken to compare an enterprise which produced only cattle to one which produced cattle and sequestered carbon. The findings from this analysis were used to inform the design of an experimental auction to test alternative carbon trading scenarios. An experimental workshop was conducted at seven locations across central Queensland with a range of beef producers, extension officers and consultants. Participants were presented with a scenario in which they had the choice of maintaining current management practices against altering management practices to reduce beef production and enter into a carbon sequestration contract (CSC). They were asked at what price they would enter into a CSC and how that price and likelihood of participating would change under a range of alternative contract conditions. The results of the experimental auctions found significantly higher than breakeven prices for carbon would be required before landholders would offer land as a carbon offset. Participation rates were influenced by price and also the carbon contract rules. Five rule changes were trialled and all were found to have a significant impact on reducing participation and increasing required payment levels.Farm Management,

Unravelling the economic and environmental tradeoffs of reducing sediment movement from grazed pastures

An undesirable consequence of grazing activities in eastern Australia is the quantity of sediment emptying into the Great Barrier Reef Lagoon. One of the challenges to reducing sediment loads stems from the lack of private incentives to improve land management practices. There is also a poor understanding of the financial implications resulting from the adoption of sustainable management practices, and, in particular the lack of scientific and economic knowledge linking on-farm management actions to catchment scale impacts. Bio-economic modelling has been used to identify the economic and environmental trade-offs encountered when grazing strategies are altered to reduce off-farm sediment movement from a black spear grass pasture in central Queensland.bioeconomic modelling, grazing, economic and environmental, Environmental Economics and Policy,

Quasi-option values for enhanced information regarding genetically modified foods

Issues concerning the long-term environmental and health risks associated with the production of genetically modified foods remain highly topical in Australia. It is unclear how consumers values for a precautionary approach to the release of genetically modified crops compares to the opportunity costs of forgoing economic growth associated with the use of these technologies. In this paper, an application of the contingent valuation method is reported. That technique was used to estimate quasi-option values held by consumers regarding a potential five year moratorium on the use of genetic modification in Australian agriculture. The results are compared to the estimated opportunity costs of imposing such a ban o Queensland consumers.Quasi-option values, genetically modified organisms, contingent valuation, Agricultural and Food Policy, Research Methods/ Statistical Methods,

Consumer demands for organic and genetically modified foods

Issues concerning consumer demands for genetically modified and organic food remain topical. It is unclear how consumers perceive issues associated with food production such as food safety, environmental impacts or animal welfare. It is also unclear how consumers might value potential changes in those issues in regional and metropolitan centres. This paper reports on research using the choice modelling technique to estimate and compare consumer demand for genetically modified and organic foods in Australia. The case study considers tomatoes, milk and beef commodities. The results draw comparisons between the contribution of associated factors influencing consumer purchasing decisions in a regional and metropolitan city. The results are relevant to the current policy debate regarding the introduction of GM foods.Genetically modified, organic, demand, choice modelling, Crop Production/Industries, Demand and Price Analysis, Food Consumption/Nutrition/Food Safety,

The Cleavage of Alkyl Zinc Bonds by Metallic and Organometallic Halides.

The possible mechanisms by which an alkyl group may transfer from one metal to another have been reviewed, together with evidence for these mechanisms. The nature and properties of the organic derivatives of the Group II metals have been reviewed, with particular reference to the alkylmetal halides. In the present work the relative rates of reaction of dimethylzinc, diethylzinc and di-n-propylzinc with phenylmercuric chloride were found to be in the order Me<Zn (100) < Et<Zn (450) < n-Pr<Zn (1660) in refluxing diethyl ether, by competition experiments in which mixtures of two dialkyl zincs were allowed to react with a deficiency of phenylmercuric chloride. The mechanism of the reaction of a dialkylzinc with phenylmercuric chloride under these conditions is suggested as being an SEi one, involving a closed, four-membered, transition state. The same dialkylzincs reacted at the same rate with phenylmercuric chloride in tetrahydrofuran in similar competition experiments. The reaction of diethylzinc with phenylmercuric chloride was too fast to be followed kinetically, in both solvents. Similarly the reactions of phenylmercuric iodide, ethylmercuric iodide and mercuric iodide with tetrahydrofuran solutions of "ethylzinc iodide" were too fast to follow kinetically. Investigations into the nature of "ethylzinc iodide" solutions have shown that monomeric EtZnI does exist in both ethereal and tetrahydrofuran solutions. The existence of EtZnBr in tetrahydrofuran is suggested. In these studies use was made of both N.M.R. spectroscopy and the fact that it was found in the present work that N,N,N',N' tetramethylethylene-diamine forms 1 : 1 solid complexes with these ethylzinc halides

Assessing the economic impact of an emissions trading scheme on agroforestry in Australia’s northern grazing systems

Although agriculture generates a significant portion of Australia’s greenhouse gas emissions, it also has the potential to sequester large quantities of emissions through changed land use management such as agroforestry. Whilst there is an extensive amount of agroforestry literature, little has been written on the economic consequences of adopting silvopastoral systems in northern Australia. This paper reports the economic feasibility of adopting complimentary agroforestry systems in the low rainfall region of northern Australia. The analysis incorporates the dynamic tradeoffs between tree and pasture growth, carbon sequestration, cleared regrowth decomposition rates and livestock methane emissions in a bioeconomic model. The results suggest there are financial benefits for landholders who integrate complimentary agroforestry activities into existing grazing operations depending on the rules of the carbon accounting framework used.carbon sequestration, financial analysis, carbon accounting framework, Agroforestry, Resource /Energy Economics and Policy,

Distributed Mathematical Model Simulation on a Parallel Architecture

The aim of this article is to discuss the design of distributed mathematical models and suitable parallel architecture of computers. The paper summarises the author’s experience with mathematical modelling of decomposed information systems of a simulator. Conclusions are based on the theory of the design of the computer control systems. The author describes computers that create a distributed computer system of a flight simulator. Modelling of a time precision of mathematical model of the speed of a simulator system is done by describing equations. The qualities of models depend on the architecture of computer systems. Some functions of other sections of POSIX are also analysed including semaphores and scheduling functions. An important part of this article is the implementation of computation speed of aircraft in multicore processor architecture