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>Magister Scientiae - MSc / Pelargonium capitatum is a plant that is popular in essential oils. The isolated essential oil constituents from the flowers and leaves of the plant were obtained by hydrodistillation followed by GC-MS analysis. The following essential constituents were obtained in abundance from flowers and leaves 8, 11-octadecadienoic acid and citronellol, caryophyllen, α-cubebene, copaene, azulene, pentacosane, 9, 12- octadecadienoic acid. Crude extracts from Pelargonium capitatum were fractionated through various chromatographic techniques in order to achieve satisfactory separations. Four compounds were characterized and the structural elucidation were unambiguously confirmed by spectroscopic methods including one and two-dimensional nuclear magnetic resonance and high resolution mass spectroscopy. The compounds were isolated from the ethyl acetate (2) and hexane (2) extracts, respectively. The four isolates were identified as quercetin, quercetin xylopyranoside, β-sitosterol and undecaprenol. The isolate and the different extracts were tested for cytotoxicity using brine shrimp lethality test. The results showed that quercetin and the extracts were active with hexane extract showed the highest cytotoxicity level of 1.5μg/ml. To the best of our knowledge quercetin xylopyranoside, β-sitesterol and undecaprenol compounds are reported for the first time from Pelargonium capitatum.

Questions relating to economic performance, biological conservation and variation in resource abundance and harvest of ocean shrimp have led to increasing pressure for management action. Developing effective management policies for this highly variable resource requires a comprehensive understanding of the fishery and marine processes. Important factors in understanding the fishery include oceanographic influences on shrimp distribution, abundance, and fishery and market dynamics. Fishery regulations for Oregon ocean shrimp, Pandalus jordani, are designed to protect age one shrimp from overharvest and sustain long-term fishery benefits. The research presented in this dissertation describes the development and analysis of analytical models ranging from classical, biological based yield-per-recruit management approaches to optimization models that incorporate economic variables and environmental recruitment relationships. This research is composed of three separate but complimentary papers regarding management of the ocean shrimp fishery. In the first paper, a yield-per-recruit analysis found that high natural mortality rates lead to yield maximization by selecting relatively young shrimp. The revenue-per-recruit analysis found that by delaying the season opening date, shrimp revenue would generate higher total revenues, while decreasing total fishing mortality and harvest. The second paper utilized a nonlinear optimization model with cost and market information to compare harvest strategies on fishery yield, gross revenue and discounted net present value (NPV). A key extension modeled a vertically integrated fishery from harvest through processing and compared harvest strategies based on wholesale prices, shrimp quality and processing yields. The optimization model that generated high yields exhibited high levels of effort and landings but low profits and NPV. The revenue policy maximization resulted in allocation of seasonal effort that produced high value older shrimp. NPV maximization generated high value shrimp landings with lower seasonal effort. Variability in shrimp recruitment and the impact on fishery utilization, income and efficiency was analyzed in the third paper. The optimization model that incorporated a stock recruit relationship and effects of environmental variables indicated an optimal harvest strategy that protects the spawning stock within a season and closes the fishery in years of poor recruitment. The results of this research highlight the complexity of management decisions when environmental forces and economic factors are jointly considered. / Graduation date: 2005

The purpose of this research was to explore the impact of finfish bycatch on the ocean shrimp Pandalus jordani fishery using two methods. One method looked at the breakage of the shrimp by finfish bycatch in the nets. The other looked at the impact of bycatch on fishing decisions. At-sea research found that finfish bycatch contributes to the breakage of ocean shrimp. However, the impact is small relative to breakage caused by other handling procedures. Bycatch was measured from each net of a double-rigged shrimp vessel, where one side employed a Nordmore grate bycatch reduction device (BRD) and the other served as a control. Shrimp catch was controlled for BRD use and catch day, and sampled throughout processing to evaluate breakage. At greater than 50% bycatch there was a significantly higher percentage of broken shrimp in the control side than in the BRD side for samples taken at the first and third sampling point (p<0.05). After this point the differences became non-significant. The percent breakage increased from a mean 2.4% broken before placement in the hold to a mean 18.0% broken in the final product. The impact of bycatch on fishing decisions was evaluated by distributing an expanded logbook to volunteer Oregon shrimp vessels in 1998. Logbook questions addressed the reasons and time involved for running to initial fishing grounds, relocating overnight, relocating between tows, dumping tows, and modifying gear. Completed logbooks were collected from 20 vessels representing 263 trips, 1043 fishing days, and 4727 tows. A soft mesh BRD was used at some point by 25% of vessels on 8.7% of trips and 3.3% of tows. Bycatch did not figure prominently in reasons given for choice of initial fishing grounds, relocating between fishing days, or relocating between tows. Bycatch was the main reason cited for dumping tows. In total, 430 (9%) tows were dumped. The estimated weight of fish and shrimp dumped equaled 11.3% and 0.3%, respectively, of the landed shrimp catch. Pacific whiting Merluccius productus caused 81.4% of the tows dumped due to bycatch. Opportunity costs attributed to bycatch alone were equivalent to net revenue resulting from 12.3 tows or $3,203 per study vessel. At the fleet level, opportunity costs due to dumped tows totaled 1,227 effort hours, 32.4 trips, or $155,070. This equates to a 4.6% loss in gross ex-vessel revenue. / Graduation date: 2002

This study aims to analysis the seasonal fluctuation fisheries assemblages and fishing yield by weight and amount of per unit effort using commercial shrimp beam trawlers at the waters off Yunlin, southwestern Taiwan during 1997-2007. In total, 47 sampling cruises, 320 taxa belonging to 205 genera and 102 families were identified. Among these, twelve species occurred greater than 80%. The species number of teleost fish were the most in each sampling. The total fish yield were 3032.9 kg and 304,680 individuals in the sampling period. Shrimps, the target species of the commercial beam trawler, were collected 945.7kg (31.2% of the total fish yield) and 181,050 individuals (59.4% of the total fish yield) , both are the most dominant fish yield among the fishing communities. The teleost fish (865.2 kg, 31.2%) and snails (73,868 individuals, 24.2%) were with the most fish yield in terms of weight and amount, respectively. The dominant species presented a seasonal pattern with a highly oscillation yield in both weight and biomass of the species in the same season each year. Thirteen species were recognized as the mainly harvested animals in of seasonal the commercial shrimp beam trawler. This study also showed that the shrimp, Parapenaeopsis hardiwckii, from February to May, and the portunid crab, Portunus sanguinolentus, from August to November in each year had the most production by cluster analysis. Since, the coastal zone at Yunlin were selected for constructing as an industrial park from May, 1998. Therefore in related to the development of the industrial park, to compare the production of 13 mainly harvest animals individually between three industrial developmental stages (pre-development: 1997.1-1998.2, development: 1998.5-2004.12 and post-development: 2005.2-2007.12). The results showed that the production of 3 species, Tanea lineate, Glossaulax didyma and Parapenaeopsis hardiwckii, decreased significantly (p< 0.05), where as of 2 fish species, Arius maculates and Chrysochir aureus, increased. By in large the other species was not remained the same after the construction.

Ecophysiological responses of Litopenaeus vannamei were evaluated as functions of 1) salinity and animal size, 2) temperature and the animal's nutritive state, and 3) dissolved-oxygen concentration and animal size. Growth rate, routine metabolic rate, limiting oxygen concentration for routine metabolism, and marginal metabolic scope were determined for L. vannamei maintained and tested at salinities of 2, 10, and 28 ppt, all at 28 C. Routine metabolic rate (RMR) was not demonstrably dependent on salinity but decreased with increasing shrimp weight. Limiting oxygen concentration for routine metabolism (LOCr) was independent of shrimp weight up to 9 g; but, for larger shrimp, decreased with increasing weight. Marginal metabolic scope (MMS = RMR/LOCr) also decreased with increasing shrimp weight and was independent of salinity for shrimp weighing up to 9 g; but, like LOCr, MMS was dependent on salinity for larger shrimp. Growth rate was significantly less at 2 ppt than at 10 or 28 ppt, which gave similar growth rates. The effects of four temperatures (20, 24, 28, and 32 C) on growth, RMR, LOCr, and MMS were examined for fed and starved L. vannamei. Routine metabolic rate increased with increased temperature both for fed and starved shrimp. Marginal metabolic scope and growth appeared to be positively related and, at 20 C, seemed to induce a state of metabolic torpor. Data from the study of chronic effects of hypoxia (~2 mg O2 L-1) vs. normoxia (> 5 mg O2 L-1) on ecophysiological responses indicated that although low-DO environments can depress RMR and growth in L. vannamei, animals grown under hypoxic and normoxic conditions did not differ in their metabolic responses upon acute exposure to hypoxia, providing no evidence of acclimation to hypoxia in L. vannamei. Data from the above experiments were used to parameterize Ecophys.Shrimp, a computer simulation model of shrimp growth in time-varying environmental regimes. One unified model was able to simulate all my experiments; and, with only minimal adjustment of the model parameter MMSO, it also adequately simulated studies taken from the literature. Thus, Ecophys.Shrimp seems capable of realistically representing the ecophysiological dynamics of shrimp metabolism and growth in various culture systems.

The Leslie¡¦s method was employed for the estimation of stock size and catchability coefficient of Sakura shrimp on the southwestern coast of Taiwan from Nov 2002 to May 2004. After analyzing the stock size and catchability coefficient and then applying those estimated value for the optimal conduction of open-access and bioeconomic optimum, the evaluation of the variation under both conductions were available and simulations run by the catch data also can be obtained and useful in comparing with the real situation. By assuming all bioeconomic parameters varied within a reasonable range, we did the comparative static analysis and expected to shed the light on the impact those parameters brought to the stock size.

This study focused on the spatial and temporal variation of water qualities and the phytoplankton and zooplankton standing crop of southwestern Taiwan. Data were collected from 30 cruises of research and fishermen vessels between August 1999 and December 2002. The yield of sergestid shrimp in this area was also analyzed for possible relationship with physical environment. Concentrations of phosphate and ammonia in the study area were highest in autumn, while the concentration of dissolved silicon peaked in winter; In spring, the concentration of all three nutrients similarly dropped to their lowest level. Regardless of seasonal variation, the concentration of dissolved silicon positively correlated with the water depth around the year. Positive correlation was found between phosphate and river discharge rates of Kao-Ping River in autumn. Negative correlation was found in spring, summer and autumn for ammonia, negative correlation in spring and autumn for dissolved silicon, respectively. Variations of phytoplankton in seasons and locations were also studied. Chlorophyll a blooms in winter but was at lowest level in summer. Concentration of total-chlorophyll a decreased with distance from the shoreline. Concentration of total-chlorophyll a negatively correlated with the river discharge rate in summer, but was positively correlated in winter. Nanophytoplankton (< 10 £gm) appeared to be the major component of phytoplankton. High standing crop of copepods was found at regions near the Liu-Chiu Yu, the estuary of Kao-Ping River, and near the coast. Significant positive correlation between phytoplankton and Copepoda standing crop indicates possible feeding and grazing relationship between them. Changes of the concentration of chlorophyll a corresponds with relative levels of phosphate and ammonia in some seasons. The period with the highest phytoplanktonic standing crop also coincides with the high yield season of sergestid shrimp (from November to March). Variation of Copepoda standing crop does not follow seasonal changes of phytoplankton. Based on the results from General Linear Model analysis, lunar phases, river discharge rates of Kao-Ping River, and the Fishing Effort (hrs/haul-boat) have significant effects on the yield (kgs/haul-boat) of sergestid shrimp respectively. The yield of sergestid shrimp in the full moon period and the last quarter of a lunar month is higher than other periods. The occurrence of thick thermocline water layer matched with the period of high CPUE of sergestid shrimp.

Thesis (M.S.)--University of Tennessee, Knoxville, 2003. / Title from title page screen (viewed Mar. 22, 2004). Thesis advisor: J. Larry Wilson. Document formatted into pages (viii, 54 p. : col. ill.). Vita. Includes bibliographical references (p. 50-53).