Elizabeth H. Petersen

The impacts of greenhouse gas abatement policies on the predominantly grazing systems of south-western Australia

Three policy options for greenhouse gas abatement in the predominantly grazing systems of Western Australia are analysed. The two taxation policies (a tax on total emissions, and a tax on methane emissions only) are only effective at extreme tax rates (

Bioeconomic Analysis of extensive mud crab farming in Vietnam and analysis of improved diets

85/t CO2 equivalents)where farming systems are no longer economically viable. The third policy option, emission restrictions, allows farms to remain profitable at approximately four times greater abatement levels than the taxation policies, and is found to be the most effective and efficient policy option studied. However, it is concluded that the introduction of any farm-level policy for greenhouse gas abatement would be politically unpopular and, in the absence of swift and innovative technological change, would cause the current farming systems to fail and be replaced by alternative land-uses.

Greenhouse Gas and Groundwater Recharge Abatement Benefits of Tree Crops in South-Western Australian Farming Systems

The aim of this analysis is to conduct bioeconomic analysis of mud crab growout farming in Vietnam and to analyze the cost-effectiveness of potential manufactured feed diets for these farms. Profitability of these farming systems is found to be moderate compared with other seafood growout operations in the country, but return to investment is relatively high. Costs are dominated by seed and labor. Feed and other input costs are low indicating the low input, extensive nature of current mud crab farming systems. It is found that forthcoming pelleted diets are likely to increase a farmers net revenue by up to 24%, depending on the region. As mud crab farming systems intensify, it is likely that farmers will be increasingly better off with the introduction of pelleted diets, especially if they have the benefit of reducing mortality (through the inclusion of vitamins and other additives).

Bioeconomics of reservoir aquaculture in Vietnam

The indirect benefits of a commercial tree crop for greenhouse gas and groundwater recharge abatement are analysed. Oil mallees are introduced into a whole-farm linear programming model as a source of income, an offset to greenhouse gas emissions from the mixed sheep and cropping enterprises and as a source of groundwater recharge abatement. The profitability of oil mallees is found to be very sensitive to the discount rate, yield and price assumptions and the relative profitability of other farm enterprises (especially the wool enterprise). Under standard assumptions where oil mallees are profitable, the trees significantly reduced greenhouse gas emissions and groundwater recharge and the farm remains profitable. If farm-level policies are introduced for greenhouse gas abatement, without tree crops or some other technological change, the current farming systems would fail and be replaced by alternative land uses.

Institutional Economics and Fisheries Management

Reservoir aquaculture has developed in an ad hoc manner in Vietnam to date. A bioeconomic model of reservoir aquaculture in northern Vietnam is presented in this paper to highlight issues of developmental importance of reservoir aquaculture in Vietnam. The biological model is based on a conventional von Bertalanffy growth function and the economic model is a net revenue function. The greatest source of costs for the operation are restocking costs (75%) and contract labor costs (18 percent). Benchmark net revenue is approximately 8.7 million VND (approximately US

THE IMPACT OF PRICE AND YIELD RISK ON THE BIOECONOMICS OF RESERVOIR AQUACULTURE IN NORTHERN VIETNAM

539). The stocking density, length of time between stocking and harvest and harvesting efficiency have the largest impact on net revenue. The inclusion of aquaculture into government fisheries development plans with research focused on development of fingerling production, preparation of flooded land for aquaculture production and strengthening institutional arrangements for reservoir leasing and credit arrangements, is likely to lead to increased capitalization and investment, and therefore greater revenues for local fishing populations.

Potential Benefits from Alternative Areas of Agricultural Research for Dryland Farming in Northern Syria

Elizabeth H. Petersen argues that economists and other social scientists are increasingly focusing their attention towards institutions (defined as humanly-devised rules) as critical determinants of economic, social and political growth and development. Institutions responsible for the governance of fishery resources have experienced dramatic reforms over the last few decades, stimulated by increased competition for access and exploitation of resources, leading to emerging scarcity of these very resources. This book aims to contribute to the biological and economic sustainability of fish resources worldwide by providing an analysis of fisheries management in the context of new institutional economics.

Recent changes in the bioeconomic of finfish mariculture in Vietnam.

A bioeconomic model of reservoir aquaculture in northern Vietnam is used to investigate the impacts of fish price and yield variability on the level and riskiness of expected net revenue. Net revenue is volatile compared with similar enterprises in other countries, mainly due to high yield variability. This reflects the nascent nature of the industry in Vietnam and the potential for efficiency and productivity improvements. Increasing production intensiveness, as well as reservoir size, was found to increase profits and decrease revenue risk. Among the management parameters studied, expected net revenue was found to be most sensitive to the length of the production cycle and to the harvest rate, while revenue risk was most sensitive to cycle length. Reservoir size was found to affect net revenue less than anticipated. Although common carp monoculture was found to maximize expected profit, the current species mix minimizes risk, thereby suggesting high risk aversion by northern Vietnams poor farmers.

Bioeconomics of cobia, Rachycentron canadum, culture in Vietnam

This study is intended to contribute to the setting of priorities for agricultural research in two regions of northern Syria. A whole-farm economic model based on production data from 8-year field trials, and market and farmer surveys for the same years, is used for each region. The models are run with 10% increases in approximately 30 parameters of the farming system, and the parameters are ranked according to their effect on whole-farm profit. Results indicate that improvements in wheat grain yields have the greatest effect on income, with improvements in lentil grain yields ranking second. Other parameters rate considerably below these two. The lower-ranked parameters include the energy content of barley grain, the lambing percentage, the energy content of lentil straw, and milk production. Extensive sensitivity analysis with plausible economic and environmental changes found that this ranking is robust under all changes for both regions studied.

Bioeconomics of Grouper, Serranidae: Epinephelinae, Culture in Vietnam

Finfish mariculture farmers in Vietnam are making careful practice change decisions in reaction to a number of economic drivers. These economic drivers are centred on trends of increasing input costs and decreasing output prices. In general, mariculture farmers are adapting to the cost-price squeeze in a number of ways, including increasing stocking densities and area, and by adopting risk-reducing strategies (decreasing grow-out periods and using a larger number of smaller ponds to spread mortality risk). However, there is still a shortage of good quality low-cost fingerlings which is constraining farmers’ ability to adapt to the cost-price squeeze. The dominant input cost source is feed. Most farmers are still reliant on trash-fish feeds. With low and decreasing feed conversion ratios for trash-fish, there is decreasing incentive for these farmers to change to pelleted diets. Southern Asian seabass farmers have made the practice change to pellets, but feed conversion ratios are high preventing significant economic gains from making the change. This research highlights two key areas where policy, research and extension initiatives can have a significant impact on the long-term economic and environmental viability of mariculture operations in Vietnam while protecting fish stocks: firstly, ensuring the widespread availability of low-cost hatchery-produced fingerlings, and secondly, encouraging practice change from trash-fish diets to the well-managed use of manufactured pelleted diets.