Thesis (Ph. D.)--University of Hawaii at Manoa, 2003. / Includes bibliographical references (leaves 109-118).

Orientador: Adilson Fransozo / Resumo: Artemesia longinaris Spence Bate, 1888 é considerada uma espécie monotípica endêmica das zonas costeiras do Atlântico Sul Ocidental. Vem sendo recentemente explorada comercialmente devido à queda nos estoques dos camarões de maior interesse comercial. Esse estudo visou comparar a distribuição espaço temporal da A. longinaris em um intervalo de 20 anos (novembro/1988 a outubro/ 1989 e novembro/2008 a outubro/2009) na Enseada da Fortaleza, em Ubatuba, São Paulo. Em ambos os períodos os indivíduos e fatores ambientais (temperatura e salinidade da água de fundo e superfície, sedimento) foram coletados em 7 transectos. Uma RDA foi feita para relacionar os fatores ambientais com a abundância dos indivíduos. O teste de Mann-Whitney foi realizado para comparar fatores ambientais e abundância dos indivíduos entre os dois períodos. Foram coletados de 3088 espécimes no primeiro período e 1252 no segundo, não havendo diferença significativa entre os períodos (p>0,05). Apesar de não apontada estatisticamente houve uma redução do número de indivíduos entre os períodos. Segundo resultados da RDA, uma forte correlação negativa entre a abundância e a classe C (silte+argila) do sedimento, mostrou que o aumento desse tipo de sedimento no segundo período, pode ter contribuído para a redução do número de indivíduos. Aliado a isso, houve menores reflexos da massa ACAS nesta enseada, ocasionando uma redução do número de indivíduos. Esta massa de água reduz as temperaturas de fundo, sendo que a espé... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Artemesia longinaris Spence Bate, 1888 is considered a monotypic species endemic to the coastal areas of the Western South Atlantic. It has recently been commercially exploited due to the fall in stocks of shrimps of major commercial interest. This study aimed at comparing the temporal distribution of A. longinaris over a period of 20 years (November / 1988 to October / 1989 and November / 2008 to October / 2009) at Fortaleza Bay in Ubatuba, São Paulo. In both periods the individuals and environmental factors (temperature and salinity of the bottom and surface water, sediment) were collected in 7 transects. An RDA was made to relate environmental factors to the abundance of individuals. The Mann-Whitney test was performed to compare environmental factors and abundance of individuals between the two periods. There were collected 3088 specimens in the first period and 1252 specimens in the second, with no significant difference between the periods (p> 0.05). Although not statistically indicated, there was a reduction in the number of individuals between the periods. According to the results of the GDR, a strong negative correlation between the abundance and class C (silt + clay) of the sediment showed that the increase of this type of sediment in the second period may have contributed to the reduction of the number of individuals. Along with this, there were smaller reflexes of the ACAS mass in this cove, causing a reduction in the number of individuals. This body of water redu... (Complete abstract click electronic access below) / Mestre

Farm-raised marine shrimp are Thailand's most important agricultural export, earning $US 2.4 billion annually in revenues for the government. Thailand's experience with intensive shrimp culture spans almost two decades. First generation marine shrimp farms. located mostly in coastal areas. have given way to a second generation of shrimp farms located in freshwater and brackishwater areas. The success of these second generation farms is attributed to the discovery by farmers that they can successfully cultivate a marine species of shrimp under low-salinity conditions. The nature of this innovation. referred to as inland or low-salinity culture. has greatly increased the potential for establishing shrimp cultivation much further from the coast than previously believed possible. While there are still many coastal shrimp farms. the most significant industry expansion since the mid 1990s has occurred in the irrigated floodplain and delta of Thailand's central plain. The output from low-salinity shrimp culture in freshwater areas now accounts for a large and rising proportion of total Thai production. and is a significant component of world production. This dissertation investigates the development of low-salinity shrimp culture in Thailand. The key findings were the firsthand documentation of the factors contributing to the development of low-salinity shrimp farming in freshwater environments. This study documents the innovations in hatchery and farming techniques. examines the development of the saltwater infrastructure required to sustain inland shrimp ponds. and identifies the land and water management challenges associated with low-salinity culture from both the government and producer perspective. The methodology adopted to achieve the research objectives consisted of secondary data review, farm and key informant surveys utilizing semi-structured interviews. informal interviews and discussions. and statistical description and analysis. The research was completed during four separate field investigations totaling ten months over an eight-year period from 1997 to 2004. Recommendations are offered to improve the environmental management of low-salinity shrimp culture.

No description available.

No description available.

Thesis (Ph.D.) - James Cook University, 2002. / Bibliography: leaves 222-244.

The overarching aim of this research was to improve understanding of the synergies and trade-offs between economic and domestic food security benefits associated export-oriented shrimp and prawn aquaculture in a fragile developing country environmental context. The research scope covers the entire ‘seafood system’ incorporating production, distribution, trading and consumption in the south-west coastal region under greater Khulna District, Bangladesh. The primary research objective was to understand causal factors in variation of seafood nutritional quality and health outcomes, exploring correlations with seafood consumption across a range of agro-ecological, aquatic farming systems and socio-economic conditions. The study also focused on differences in intra-household allocation with a special focus on adolescent girls, being amongst the most vulnerable members of society. These objectives necessitated a highly inter-disciplinary approach to understand complex interactions between biophysical aspects (e.g. where and which species are most effective in supplying essential nutrients) and the social norms of food allocation. Fieldwork was conducted in Satkhira, Khulna, and Bagerhat Districts of Khulna Province over 17 months during 2012 to 2015. Four villages across a peak-annual surface water salinity gradient; high saline (>10 ppt), medium saline (>5<10 ppt), low saline (<5 ppt) and freshwater (<0.5 ppt) were selected for case-studies. The thesis begins with a literature review of the evolution of shrimp and prawn farming in Bangladesh and the wider region and identification of knowledge gaps. Research resolved from district to community to household level. Key informant (KI) interviews were used to establish well-being criteria (based on a range of 5 social and economic assets) at community level. In each community a census of households (n=1082 households) were derived from the same interviews and KIs asked to ranked households on the established well-being criteria. Results were validated through a short interview of all the identified households (HH). This sample-frame provided the based for two concurrent survey efforts. Stratified-random selection of 160 HH on two well-being categories (better-off and worse-off) for ‘farm level’ analysis using a semi-structured questionnaire. Key topics included inputs/outputs characteristics, economic benefits and the fate of farmed products were evaluated. Another 240 households with single adolescent girls were selected from the same frame, again with randomized-stratified sampling based on well-being categories for ‘intra-household’ analysis. This resulted in selection of 60 HH per community consisting of 30 ‘better-off’ and 30 worse-off households (further analysis was conducted on a range of secondary sampling outcomes based on livelihood options, intra-household food distribution and aquatic farming assets). A 24-hour food recall method, food frequency questionnaire, food photography and measuring cup sets were used to estimate individual members’ food consumption at the household level. Anthropometric measures (stunting, wasting, BMI, MUAC) and biomarkers (omega-3 index in RBC and LC n-3 PUFA/LC PUFA in whole blood cell) were used to assess food security outcomes of adolescent girls (n=200 subject). In an entirely separate effort, samples of shrimp/prawn and fish polyculture species (57 species and 9 by-products, 1 live feed; n=672) were collected from the major agro-ecologies (four saline gradients; HS, MS, LS and FW) and culture systems (extensive, semi-intensive, intensive, organic and pocket gher). At least 3 sites from each saline gradient (3×4=12 sites) were selected for sampling and pooled samples to represent all the culture system in the region. The major macro and micronutrients of the collected species were analysed and these datasets were used to know the nutritional distribution among the family members in household level study. Two aggregate indices of wealth (or well-being) and aquaculture were developed based on a range of quantitative (ordinal and interval) measures. Principle Component Analysis (PCA) was used to understand how aquaculture influences on wealth gain. Wealth index of the same social well-being did not differ among the agro-ecologies. However, the aquaculture index was varied in agro-ecologies. Most of the households (60-80%) were involved directly in aquaculture however, a majority portion of the households was worse-off (48-64%). Both HS and LS area had more livelihood options due to their proximity to mangrove forest Sundarbans and city amenities, respectively compared to MS and FW area. Ownership of the land did not influence any involvement in aquaculture and yields but he willingness and risk-absorbing capacity of the farmers were the main factor to get involve in aqauculture. In aquatic farming system the importance of export-oriented shellfish yield gradually decreased from HS to FW area (55-20% by volume). The intentional stocking of finfish and PLs were common across the saline areas however the wild caught juveniles and hatchery originated fingerlings were usual in higher and lower saline areas, respectively. The low priced tilapia took the place of wild recruited mangrove fishes in MS area. Diseases, especially the devastating white spot virus (WSSV), frequency were higher in higher saline areas. The indicators like wild recruitment, salinity, water productivity and water management also a vital factor to gain yield. The integration of aquatic and terrestrial crops (rice and dyke crop) in the lower saline areas provide higher yield compared to higher saline areas. However, the net economic returns were largely determined by the aquatic products. The income of ghers in FW and MS area was sensitive to the lower prices of freshwater finfish and tilapia. The protein content in shellfish was higher than the other finfish, however, lower in other essential nutrients. Species living in the higher saline areas contained higher total n-3 PUFA (in weight) and LC n-3 PUFA/LC-PUFA compared to the same species living in lower saline areas. Small Indigenous Species (SIS) and Self-Recruiting Species (SRS) were proven to provide higher micronutrients and total n-3 PUFA than larger fish. Seafood that destined for the international markets contained less n-3 PUFA and micronutrients in comparison to the domestically consumed fish. Customary intra-household food distribution disparity (mainly fish) still exists at household levels where females, especially adolescent girls, were deprived. Fish consumption (>77 g /capita/day) and fish originated protein supply (>25% of total protein intake) was higher than the other part of Bangladesh. The protein consumption of adolescents was 2-3 times higher than the Recommended Nutritional Intake (RNI). However, the energy intake was lower than the required level. High protein, low energy consumption was not reflected in body mass. Micronutrients (zinc) consumption was above the RNI level. However, iron and calcium consumption was less than the RNI. The n-3 PUFA in RBC of adolescent girls accurately reflected their access to, and availability of, oily fish. In the omega-3 index (n-3 PUFA in red blood cell) both HS and MS areas, adolescent females were in the intermediate stage (4-8%), and rest of the two areas were in the undesirable stage (<4%). The n-3 LC-PUFA was around 20-30% of total LC-PUFA content in whole blood and gradually decreased from higher saline to lower saline areas. The thesis concludes that the gher based aquatic animal farming in S-W Bangladesh is a dynamic system operated by both rich and poor. The salinity level and the presence of mangrove forest make the farming system dynamic. The holistic scenario suggested aquaculture in ghers is a family driven small scale polyculture where varieties of aquatic foods are produced both for global and local value chain. Higher amounts of valued products (both in terms of nutrition and price), less disease susceptibility, more alternative livelihood options both in HS and LS were found in better position than the other two sites, however the nutritional content of fish and its manifestation in adolescents strongly mirrors agro-ecologies irrespective of social position of households. The thesis provides an important, grounded importance of the system and the linkage of the community people for livelihoods, food production and food security. The dynamic systems were understood and effective messages formulated for the policy makers. In doing so, the thesis contributes to an understanding of how small-scale polyculture equally benefited local food security and macroeconomic growth of a developing country.

Aquatic toxicity tests are increasingly being used in water resource management worldwide, and currently in South Africa, policy and legislation are being drafted to reflect this international trend. While standard toxicity test methods and test organisms are being considered to develop and set water quality guidelines and effluent discharge limits, it is not clear whether guidelines and discharge limits set using these standard test organisms will be sufficient to protect South Africa’s scarce water resources. As part of ongoing research to investigate the use of indigenous riverine organisms as toxicity test organisms a number of potential species have been identified, including the freshwater shrimp Caridina nilotica. For much of the history of aquatic toxicological data the bulk of the data has been generated by acute toxicity testing, based on short exposures and using mortality as the response end point. There are relatively few chronic, longterm tests with sub-lethal endpoints. However, it was recognized that information about longer exposure durations and non lethal response endpoints was needed, instead of mortality. Chronic tests can provide a more environmentally realistic measure of chemical toxicity than acute toxicity tests. Caridina nilotica has been identified as a potential standard toxicity test organism, as it is widely distributed, easy to find and it occurs in flowing waters. It is an indigenous species which can be easily cultured and maintained in the laboratory and is also ecologically important. Both adults and juveniles have been used successfully in acute toxicity tests at the Institute for Water Research (Rhodes University) and the ability to rear the organisms under laboratory conditions has allowed the development of chronic toxicity tests using C. nilotica. Chronic early life stage tests include continuous exposure of the early life stages, which are presumed to be the most sensitive for aquatic organisms. This study reports on the embryonic development of C. nilotica at the culture temperature of 24⁰C. Morphological developmental stages were monitored and measured and 7 developmental stages were identified. Based on the measurements of the features that were identified, toxicity tests using the reference chemicals sodium chloride (NaCl), sodium sulphate (Na₂SO₄) and cadmium chloride (CdCl₂) were undertaken to test the suitability of C. nilotica embryonic development for chronic toxicity tests for use in water resource management. The length, width, length:width ratios and area of the features decreased in size when exposed to the chemicals. The Lowest Observed Effect Concentration (LOEC) values were 2000mg/L for Na₂SO₄, 3000mg/L for NaCl and 0.31mg/L for CdCl₂. The No Observed Effect Concentration (NOEC) values were 1000mg/L for Na₂SO₄, 2000mg/L for NaCl and <0.31mg/L for CdCl₂. Further research on the teratogenic effects of single chemicals and industrial effluent on developing C. nilotica embryos needs to be undertaken in order to evaluate the described test protocol for use in water resource management.

Copies of author's previously published articles inserted. / Bibliography : leaves 201-217. / ix, 216 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Concentrates on the settlement and nursery stages of the life history of Panaeus latisulcatus over a seven year history. Key nursery areas within the Gulf of St. Vincent were monitored between October 1989 and June 1996. It was determined that the best sampling technique was the use of a fully enclosed jet net. A mean index of abundance calculated from these trawls was used to estimate the relative abundance in the area sampled. No particular trend in post larval settlement patterns and juvenile abundance was obvious. A longer time frame may be required to observe significant changes in this species. / Thesis (Ph.D.)--University of Adelaide, Dept. of Environmental Biology, 1999

Copies of author's previously published articles inserted. / Bibliography : leaves 201-217. / ix, 216 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Concentrates on the settlement and nursery stages of the life history of Panaeus latisulcatus over a seven year history. Key nursery areas within the Gulf of St. Vincent were monitored between October 1989 and June 1996. It was determined that the best sampling technique was the use of a fully enclosed jet net. A mean index of abundance calculated from these trawls was used to estimate the relative abundance in the area sampled. No particular trend in post larval settlement patterns and juvenile abundance was obvious. A longer time frame may be required to observe significant changes in this species. / Thesis (Ph.D.)--University of Adelaide, Dept. of Environmental Biology, 1999