Browsing by Author "Kauffman, Daniel E."

Now showing 1 - 3 of 3
  • Thumbnail Image
    An Economic Evaluation of the Nutrient Assimilation Potential for Commercial Oyster Aquaculture in the Chesapeake Bay
    Miller, Alexander Louis (Virginia Tech, 2009-01-08)
    The Chesapeake Bay states continue to struggle to achieve the water quality goals set out in the Chesapeake Bay Agreement. While policy efforts to combat eutrophication tend to focus on reducing nutrient loads at point and nonpoint sources, waters of the Bay can be improved through an increase in the assimilative capacity of the ecosystem, which would remove nutrients (called nutrient assimilation services) from ambient waters. The filtering capacity of the native oyster, C.virginica, is a widely recognized means to enhance water quality. With an increase in the number of oysters in the Bay, and no decrease in wild stocks, oyster aquaculture has the potential to also increase the nutrient assimilation capacity of the ambient environment. Yet the expansion of commercial aquaculture in the Bay has been limited by financial constraints. Increased water quality services might be forthcoming if oyster aquaculturists received financial compensation for the nutrient removal services they provide. Based on previous research, this study develops a procedure for estimating annual nutrient removal from a given size oyster aquaculture facility. Next, a firm level bio-economic simulation model was constructed to estimate the amount of compensation needed by a commercial oyster aquaculture firm to make a new investment in oyster aquaculture. The amount of compensation needed is interpreted as the cost of providing nutrient removal by oyster aquaculture. Results indicate that under many circumstances, nutrient removal services can be provided by oyster aquaculture facilities at a per unit cost comparable with some non-point and point source nutrient removal technologies. Finally, a select number of funding resources were identified as potential outlets for creating payments and demand for nutrient assimilation services.
  • Thumbnail Image
    Sensory and Chemical Characteristics of Eastern Oysters(Crassostrea virginica)
    Chen, Luman (Virginia Tech, 2011-06-22)
    Eastern Oysters, or Crassostrea virginica, are an important dietary component in the Chesapeake region and have supported a major fishery in the Chesapeake for more than 100 years. Virginia oysters do not always receive attention in up-scale markets. It is possible that the lack of information on sensory characteristics of Chesapeake oysters may contribute to this problem. In order to differentiate Chesapeake oysters from other oysters, a descriptive sensory test (n=8) was conducted and chemical composition attributes were measured, including glycogen content, proximate analysis, sodium chloride content, and fatty acid analysis. Statistical differences were found for the attributes: volume of liquor, gray/brown and tan colors, roundness of shell, plumpness and salty taste when comparing eastern oysters from Chesapeake to oysters from Rhode Island and New Brunswick, Canada. The glycogen contents in eastern oysters followed the reproductive cycle and glycogen increased from September to December, and started to decrease by April. There were small but significant (p<.05) differences in the contents of moisture, ash, protein and fat of oysters from Chesapeake and other areas. Oysters from Chesapeake had higher percentages of long-chain n-3 fatty acids, which were about 4 times higher than Beau Soleil, an oyster from New Brunswick, Canada. The high percentage of long chain n-3 fatty acids in Chesapeake oysters may be valuable for marketing.
  • Thumbnail Image
    Three Essays on Price Analysis of Summer Flounder and China's Soybean Imports
    Chen, Wei (Virginia Tech, 2009-07-09)
    This dissertation contains three papers from two projects. The first two papers (Chapter Two and Chapter Three) are from a project entitled “Managing Flounder Openings for Maximum Revenue.” The objective of this project is to (1) estimate the monthly dockside price of summer flounder and identify seasonality in this price; and (2) set up a mathematical programming model to maximize the landing revenue by allocating the federal government quota on summer flounder across twelve months. In the first paper (Chapter Two), various forms of inverse demand equations are used to estimate the dockside price of summer flounder. These models are evaluated based on their out-of-sample forecasting performance. A structural functional form is selected. In the second paper (Chapter Three), the selected price equation for summer flounder is applied into a revenue maximization model with both the federal government quota constraint and biological constraints from twelve months. The model is solved using CONPOT Solver of GAMS 21.5. The results of the scenarios indicate that the industry should move the landing effort from the period of October – February to the period of March – August. Comparing with historical data, this method can increase $44.73 million for the industry of landing summer flounder from 1991 to 2005. The third paper (Chapter Four) investigates how China's soybean import prices and domestic prices of soybeans and soybean products affect China's soybean imports. Since 2000, soybeans have been the U.S. leading agricultural exports for bulk commodities. China is the largest importer of U.S. soybean exports. For China's soybean crushing industry, imported soybeans are inputs rather than final products and used to produce soybean meal and oil. A differential production model, which is derived from a two-stage profit maximization model in producer theory, is adopted in this research. Estimates are used to calculate conditional and unconditional price elasticities for China's soybean imports from its major source countries – the United States, Argentina, and Brazil. In addition, the Divisia index and unconditional output price elasticities are obtained for China's soybean imports. Estimation results support the hypothesis that China's soybean imports are determined by its domestic demand for soybean meal, rather than soybean oil. This implies that U.S. agribusinesses should pay attention to the dominant role of China's demand for soybean meal and animal feed. U.S. agribusinesses can also use results in this research to evaluate how China's soybean imports from different source countries will change when either international market prices or China's domestic market prices change.