ix, 119 leaves : ill., maps ; 28 cm Notes Typescript Thesis (Ph. D.)--University of Oregon, 1985 Includes vita and abstract Bibliography: leaves 108-119 Another copy on microfilm is located in Archives

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-05-25T17:17:49Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Amanda Yumi Otsuka.pdf: 1257140 bytes, checksum: 4ae2b3d501e90eaac61afd7db72c977e (MD5) / Made available in DSpace on 2017-05-25T17:17:49Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Amanda Yumi Otsuka.pdf: 1257140 bytes, checksum: 4ae2b3d501e90eaac61afd7db72c977e (MD5) Previous issue date: 2014-02-11 / A plataforma continental de Pernambuco caracteriza-se por possuir um declive suave, ser estreita, rasa, com águas relativamente quentes, elevada salinidade e por apresentar- se quase inteiramente coberta por sedimentos carbonáticos biogênicos. Esse ambiente é afetado pelo aporte continental, atuando como um receptor final de água, materiais e substâncias, que são transportados pelas descargas dos rios. Desta forma, as regiões costeiras são as mais afetadas pela ação antrópica. O presente trabalho apresentou como objetivo analisar a dinâmica da clorofila-a e parâmetros hidrológicos na plataforma continental de Pernambuco adjacente aos rios Jaboatão e Capibaribe. Foram realizadas coletas bimestrais, abrangendo período chuvoso e de estiagem, em um ponto situado na zona estuarina e quatro outros pontos distribuídos na plataforma. Foram analisados vários parâmetros ambientais como clorofila a, profundidade, salinidade, temperatura, oxigênio dissolvido, taxa de saturação do oxigênio, pH, nutrientes inorgânicos (N- amoniacal, nitrito, nitrato, fosfato e silicato), material particulado em suspensão. A pluviosidade foi a forçante física que mais influenciou na maioria dos parâmetros. No rio Jaboatão, a clorofila-a no estuário variou de 2,89 à 34,71 mg.m-3 e na plataforma de 0,21 à 9,67 mg.m-3 . De acordo com a ACP, a clorofila a esteve diretamente relacionada temperatura, taxa de saturação do oxigênio e inversamente com o pH, transparência da água e salinidade. No porto do Recife, a clorofila a variou entre 13,48 à 145,09 mg.m-3 no estuário e na plataforma a de 0,24 à 19,29 mg.m-3 . A ACP mostrou uma relação direta da clorofila-a com o N-amoniacal, fosfato, transparência e inversa com nitrato e material particulado em suspensão. Nas duas áreas estudadas, houve um aumento da biomassa no período de estiagem. Os pontos da plataforma que mais sofreram influência do deságue foram os mais centrais (P3 e P4), devido ao predomínio dos ventos alísios de sudeste. Após análise das duas áreas, observou-se que os estuários encontram-se poluídos e que no porto do Recife a carga de matéria orgânica é bem mais elevada do que o Jaboatão, provocando maior efeito na plataforma adjacente. Em termo de dispersão de pluma dos rios, no porto do Recife a presença do dique de proteção provoca uma certa perturbação no sentido da corrente, limitando esta pluma, para a parte mais costeira, o que não foi observado na área do Jaboatão. / The continental shelf of Pernambuco is characterized by a gentle slope, it is narrow, shallow, almost entirely covered by biogenic carbonate sediments; the water in the area is warm and has a high salinity. This environment is affected by continental input, and acts as a final receptor of water, materials and other substances that are transported by river discharge. Thus, the coastal regions are the most affected by human action. This study aims to analyze the dynamics of chlorophyll-a and hydrological parameters on the inner shelf of Pernambuco adjacent to the Jaboatão and Capibaribe rivers. The samplings were performed bimonthly at one research site on the estuarine zone and four additional sites distributed on the platform, covering the dry and rainy seasons. Various environmental parameters such as chlorophyll-a, depth, salinity, temperature, dissolved oxygen, oxygen saturation rate, pH, inorganic nutrients (ammonia, nitrite, nitrate, phosphate and silicate), and suspended particulate matter were analyzed. Rainfall was the most influent physical forcing to most parameters. In the Jaboatão River, chlorophyll-a ranged from 2.89 to 34.71 mg.m–3 in the estuary; and from 0.21 to 9,67 mg.m-3 at the platform. According to the PCA , the chlorophyll-a was directly related to temperature, oxygen saturation rate and inversely with the pH, water transparency and salinity. In the Port of Recife, chlorophyll-a ranged from 13.48 to 145.09 mg.m-3 in the estuary and from 0.24 to 19.29 mg.m-3 in the inner shelf. The PCA showed a direct relationship of chlorophyll-a with ammonia, phosphate and water transparency an inverse relationship with nitrate and suspended particulate matter. In both studied areas, there was an increase in biomass in the dry season. In the inner platform , The most central sites (P3 and P4) were the most influenced by river discharge, due to the dominance of trade winds from the southeast. After analysis of the two areas, it was observed that the estuaries are polluted and that, in the Port of Recife, the load organic matter is much higher than in Jaboatão causing greater effect on the adjacent platform. In regarding the river’s plume dispersion in the Port of Recife, the presence of the dike causes some disturbance in the direction of the current. The plume is then limited to the most coastal area. This fact was not observed in the Jaboatão area.

Submitted by Israel Vieira Neto (israel.vieiraneto@ufpe.br) on 2015-03-04T17:48:21Z No. of bitstreams: 2 DISSERTAÇÃO Natália Gomes Alves de Souza.pdf: 8365159 bytes, checksum: 4d043b551c4e12fa6c5ec2cfcf5660d9 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-04T17:48:21Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO Natália Gomes Alves de Souza.pdf: 8365159 bytes, checksum: 4d043b551c4e12fa6c5ec2cfcf5660d9 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2013-03-19 / O sistema estuarino Goiana-Megaó abriga flora e fauna variadas, sendo importante fonte de sustento das comunidades circunvizinhas. Este ecossistema tem sido impactado por diversas atividades agrícolas, industriais e aquicultura. Além disso, existe a previsão de grande desenvolvimento econômico nesta região em um futuro próximo (implementação de um polo farmacoquímico e um polo automotivo). Deste modo, o objetivo deste trabalho foi realizar um diagnóstico atual e a avaliação histórica das concentrações totais e potencialmente biodisponíveis de elementos maiores e traços, através de três testemunhos com distribuição espacial estratégica ao longo do estuário. Também se objetivou determinar a taxa de sedimentação desse sistema através da datação geocronológica pelo método 210Pb em cinco testemunhos ao longo do sistema estuarino. As concentrações de background local considerados neste trabalho para o sistema estuarino estudado foram obtidos a partir do testemunho a montante do estuário no rio Goiana, pelo fato deste ter alcançado as camadas mais antigas, depositadas a 98 anos atrás. Os elementos químicos As, Cr, Ni e Cu encontraram-se em concentrações acima dos limites estabelecidos pela legislação brasileira nos testemunhos T-2 e T-3, com valores máximos de 3,0 ppm, 102,0 ppm, 42,2 ppm e 39,6 ppm, respectivamente. As, Mo, S e Sb apresentaram fator de enriquecimento elevado em relação ao background (FE > 2), tendo sido obtido nos testemunhos à jusante do estuário principalmente entre 1915 e 1975. As concentrações de As tem provável origem geogênica (rochas vulcânicas e mineralização de Ba e Pb localizada a aproximadamente 50 km montante da área estudada), porém, assim como Mo, S e Sb, pode também ter origem antrópica (cultivo de cana-de-açúcar). Quanto à taxa de sedimentação do sistema estuarino estudado, houve uma tendência ao aumento com o passar dos anos e com o ano de 1966 como principal marco destas mudanças, sendo relacionados ao aumento da ocupação do município de Goiana e ao intenso cultivo de cana-de-açúcar na região. Apesar de todos estes fatores, este sistema estuarino ainda se encontra relativamente preservado, porém é notória a interferência antrópica na área, comprovada pelos dados geoquímicos aqui descritos, tornando necessário um monitoramento contínuo destes contaminantes ao longo dos próximos anos.

Master of Science / Department of Geology / Allen W. Archer / The Morrowan middle Bloyd sandstone of northwest Arkansas records a fluvial to estuarine transition in a drowned incised valley system. Lower portions of outcrops contain fluvially deposited, planar-tabular cross-stratified sandstone with a uni-directional southwest paleoflow. Intervals with dune scale, intricately interwoven trough cross-stratification with northeastern paleoflow is attributed to strong tidal and wave influence in the outer estuary. Upwards the middle Bloyd changes into a muddy mid-estuarine interval with heterolithic bedding and a bi-directional northeast-southwest paleoflow. Overlying this interval a marine sand about one meter in thickness can be found containing bryozoan and crinoid fossils. Overlying the middle Bloyd, the marine Dye Shale member of the Bloyd Formation marks the transition to a dominantly marine setting.

M.Sc. / Estuaries are regarded as South Africa's most productive ecosystems due to the important functions that they perform, such as providing nursery areas and feeding sites for juvenile macro-invertebrate and fish species. Furthermore, ecologically healthy estuaries are not only of critical importance since they facilitate the provision and recirculation of nutrients, they also provide conduits for catadromous or anadromous fish and act as buffers during floods. In South Africa these functions are continuously threatened by residential and/or industrial developments. It is thus essential to determine the ecological integrity (structure and function) of these systems. An ecological integrity study was carried out on the Mvoti Estuary, KwaZulu-Natal during 2004/2005. An ecological integrity study was also carried out on the Amatigulu/Nyoni Estuary, KwaZulu–Natal during the same period and was used as a reference study. The ecological integrity of the Mvoti Estuary was assessed in terms of the effects of selected abiotic drivers on specific biological responses. The study was carried out according to the guidelines of the ecological reserve determination methodologies and the resource directed measures for aquatic resources as set out by the Department of Water Affairs and Forestry. Surveys were carried out during low flow (September 2004) and high flow (March 2005) periods. Abiotic and biotic monitoring was carried out at four sites on the Mvoti Estuary and five sites on the Amatigulu/Nyoni Estuary. The abiotic components, such as the substrate composition and physico-chemical properties of the water and sediment, was analysed using standard methods. Biological monitoring included the study of the benthic macro-invertebrate-, ichthyofaunal- and avifaunal communities. The biotic and abiotic components were analysed using various indices, where applicable. The ecological integrity of a system can be assessed on the basis of its ability to carry out its natural functions. Results show that various anthropogenic activities in the upper reaches of the Mvoti River contributed to the highly modified state of the Mvoti Estuary. The abiotic drivers of the aquatic system that contributed to the modified state of the Mvoti Estuary is unacceptable water quality, a loss and/or modification of habitat and an altered hydrological pattern. As a result of the abiotic drivers, results show that the xi ichthyofaunal-, macro-invertebrate- and, to a lesser degree, the avifaunal communities also reside in a modified state. Physico-chemical, geomorphological and hydrological changes in this system resulted in the Mvoti Estuary suffering a loss in both its biological and ecological function as well as aesthetic value. It is apparent from the above that there is not only a need for rehabilitation, but also a need for an effective and continuous management strategy. This management strategy can only be successful if the biomonitoring of the system includes the effects at both economical and social levels.

Estuarine ecosystems are among the most biologically productive areas and they provide important ecosystem services such as erosion control, habitat and refugia for several species. These environments are characterized by the presence of a variety of organic matter sources due to their transitional position between rivers and the sea. The biotic compositions can undergo spatial and seasonal changes along the estuary due to the spatial and temporal fluctuations of environmental factors such as salinity, temperature and seston loads. Therefore, the different combinations of biotic and abiotic factors make each estuary a unique ecosystem. Because of this spatial and temporal complexity, the understanding of estuarine food web structure and which factors affect the trophic relationships within the ecosystem through space and time represent challenging tasks. Furthermore, estuaries are under an increasing number of anthropogenic perturbations because of the growing concentration of human populations in coastal areas. Knowledge of ecosystem structure and functioning is essential for effective conservation and management planning of coastal areas.In this dissertation, I combine the utilization of biological tracers to examine spatial and temporal variability in the food web structure within a small temperate and microtidal estuary located in South Africa. To this end, fatty acid profiles and stable isotope signatures were measured in several primary organic matter sources and consumers (including zooplankton, fishes and benthic invertebrates) during four consecutive seasons and in three different estuarine regions: upper, middle, and lower reaches. The three reaches had distinct habitat features of vegetation type and morphology, and in particular the lower reaches were colonized by the marsh grass Spartina maritima. Isotopic mixing models were used to estimate the relative contribution of each food source to the diets of invertebrates and fishes within the estuarine food web. The isotopic and fatty acid data showed similar results. In general, the lower reaches of the estuary were characterized by a higher deposition and assimilation by brachyuran crabs of carbon derived from marsh grass detritus, whiletowards the upper reaches a mixture of microphytobenthos and particulate organic matter (phytoplankton and detritus) was deposited and sustained the pelagic and benthic fauna. The highest deposition and assimilation of marsh grass detritus in the lower reaches of the estuary occurred during periods of low freshwater discharge (autumn and winter). In the upper reaches, microphytobenthos and suspended particulate organic matter were dominant basal food resources for the food web during all seasons. These results indicated that benthic consumers incorporated mainly local carbon sources from their local habitat.To clarify isotopic and fatty acid patterns I examined the trophic behaviour of the sesarmid crab Sesarma catenata through laboratory feeding experiments. Results from these experiments validated that decomposed leaves of riparian trees and the salt marsh plant S. maritima were the preferred food of the sesarmid crabs, potentially due to high bacterial loads. The remaining leaf material not assimilated by crabs, together with faecal material, are likely important subsidies for adjacent environments, hence representing an important energy pathway involving the microbial food chain. Furthermore, this dissertation showed the importance of mobile top predators as vectors energetically connecting distinct food chains within the estuary (i.e. littoral, benthic and pelagic). I concluded that a combination of physical (i.e. patterns of freshwater discharge and estuary morphology) and biological factors (i.e. organism feeding behaviour, mobility, primary productivity, the local vegetation type) influence the pattern of dominant primary organic matter sources, and therefore the food web structure along the estuarine environment. In particular, marsh grass detritus contributed substantially to the diets of estuarine fauna during periods of low freshwater discharge. Given the importance of the salt marsh habitat in providing trophic resources, it is important to preserve this environment to sustain the natural biota and ecosystem functioning.

There is a paucity of published information on fish utilization of salt marshes outside North America. This dissertation represents the first intensive examination of the ichthyofauna associated with salt marshes in southern Africa and examines the species composition, diversity, size structure, distribution and estuarine dependence of fishes that utilize salt marshes in the Kariega Estuary. The research was concentrated on Taylor's salt marsh, with comparative studies being conducted on other salt marshes and habitats within the marine dominated Kariega Estuary. The possible importance of salt marshes as feeding and refuge areas for fishes was examined, as was the role of salt marshes in the food web of the estuary. The fishes frequenting salt marshes in the Kariega Estuary were predominantly the juveniles of marine species, with Mugilidae being the dominant family. The ichthyofauna was distributed primarily in the intertidal creeks with very few specimens captured on the vegetated Spartina maritima and Sarcocomia perennis flats. The different reaches of the intertidal creek were characterised by distinct fish assemblages. The fish assemblages associated with the intertidal salt marsh creeks were significantly different from those found in the eelgrass beds, the other dominant intertidal habitat in the Kariega Estuary. The eelgrass beds were dominated by estuarine fish species and had a higher density and standing stock of fishes when compared to the salt marsh creeks. The diversity of fishes in the two habitats was however similar. The intertidal salt marsh creek ichthyofauna also differed significantly from that found in the main estuary channel. The creek ichthyofauna was dominated by 0+ juveniles while the main channel had many subadult and adult fishes. The channel habitat also had numerous large piscivorous fishes which were absent from the salt marsh creeks. The low number of piscivorous fishes, together with limited fish predation from other sources, may be the reason why salt marshes provide a refuge for juvenile fishes that frequent these habitats. Unlike previous studies on North American, Australian and European salt marshes, the dominant fish species that frequented Taylor's marsh were not recorded feeding extensively on the marsh, and those that did had a limited distribution. The role of fishes in the transfer of energy off the Kariega salt marshes is therefore likely to be minimal. A stable carbon isotope study on the dominant primary producers and consumers within the Kariega Estuary revealed that detritus originating from the high lying salt marsh plants Sarcocornia perennis and Chenolea diffusa was not utilized by fishes in the Kariega Estuary. Preliminary results indicated that the cord grass Spartina maritima may be an important energy source to the fishes in the Kariega Estuary, but further research is needed to confirm this.

Changes in the fish communities of the Breede and Mbashe estuaries were investigated in relation to the environmental variables that influence the fish assemblages in these systems. The Breede Estuary (34° 24’21.6”S, 20° 51’ 08.2”E) occurs within the warm-temperate/cool-temperate transition-zone, while the Mbashe Estuary (32o 14' 55.4"S, 28o 54' 03.7"E) falls within the subtropical/warm-temperate transition-zone along the South African coastline. The Breede Estuary was sampled (seine and gill nets) during summer (January-March) over a period of 10 years (2002-2012), while the Mbashe Estuary was sampled (seine net) during spring (October) over a period of three years (2010-2012). The proportion of tropical fish species was higher in the Mbashe Estuary compared to the Breede Estuary, while the Breede Estuary contained a higher proportion of temperate species than the Mbashe Estuary. Although the abundance of individual species in both estuaries varied, the ranking of species in the Breede Estuary was stable over the 10 year period. Multivariate analysis showed that the fish communities within each reach (upper, middle, lower) of the Breede Estuary remained similar, regardless of year. In contrast, species composition in the Mbashe Estuary differed significantly between years mainly due to differences in the river flow regime during the study period. Environmental variables responsible for structuring the fish assemblage in each estuary differed. Salinity significantly impacted the spatial fish assemblage structure of the Breede Estuary, with most of the species recorded being associated with the more saline lower reaches. The abundance of tropical species near their distributional limit in the Breede Estuary appeared to be impacted by sea surface temperature (SST) as peak total abundance of these species coincided with the warmest SST, while the lowest total abundance coincided with the coldest annual SST during the study period. The fish assemblage structure in the Mbashe Estuary was impacted by differing freshwater input prior to sampling, with flooding negatively impacting the mean total abundance, species composition and diversity in this system. The variables that influenced the fish assemblage structure of both transition-zone estuaries will be affected by climate change in the future. These variables will, in turn, determine the composition, abundance and diversity of species within these important estuarine systems. In order to measure these impacts with any degree of understanding, long-term studies on the abiotic and biotic (including the ichthyofauna) features of these estuaries are required to interpret climate change trends.

The primary production of Spartina maritima, the dominant macrophyte of the intertidal salt marshes of the Swartkops estuary, was determined for inclusion into the proposed ecosystem model. Several methods for measuring net production devised for North temperate Spartina species were used, as no single method was considered reliable for the local species. In addition, a new method was devised to take into account the aseasonal growth behaviour of S. maritima . Most energy for growth appears to be directed into leaf production, rather than shoot growth. Live net production values were 523-680 g m⁻²‚ yr ⁻¹, which are generally lower than estimates of N. American Spartina species. Total Live production of S. maritima for the whole Swartkops estuary was 495,6 x I0³kg yr ⁻¹, which is an estimation of potential food resources. Formation of S. maritima detritus by decomposition was significantly related to air and water temperatures. Thus detritus production showed a wide seasonal variation about a mean of 374 g m⁻² yr⁻¹. The total S. maritima detritus production of 307,5 x I0³kg for the whole Swartkops estuary was determined as an estimate of available food resources. Export of detrital material from Spartina marshes to estuarine waters was negligible. Even during a maximal Equinoctial tide, only 6,26 dry g m⁻² detritus was exported from the creek catchment area of Spartina stands. This study has shown that concepts evolved for North temperate estuaries should be carefully considered before being applied to local situations, particularly in view of the relatively low, aseasonal production of S. maritima and the negligible contribution of its detritus to estuarine waters. Furthermore, it is essential that utilisation of primary production by secondary producers be determined before the function of the estuarine ecosystem may be understood

This study investigated the response of macrophytes to physico-chemical factors in seven South African estuaries and showed that dominant salt marsh species that occur in different estuaries respond to the same environmental factors. The most important variables influencing distribution were elevation, water level, sediment- and groundwater electrical conductivity and depth to the water table. In permanently open estuaries (Kromme and Olifants) transect surveys identified three distinct vegetation zones i.e. submerged macrophytes, intertidal salt marsh and supratidal salt marsh. In the Kromme Estuary intertidal salt marsh (81.2 ha) covered extensive areas, whereas supratidal (143 ha) and floodplain (797.1 ha) salt marsh were dominant in the Olifants Estuary. Transect surveys identified four distinct vegetation zones (submerged macrophytes, intertidal salt marsh, supratidal salt marsh and reeds and sedges) in the temporarily open/closed estuaries (Mngazi, Great Brak, East Kleinemonde and Seekoei estuaries), although all zones did not occur in all of the estuaries sampled. In the Mngazi Estuary reeds and sedges (1.09 ha) covered extensive areas (no submerged or salt marsh vegetation was present), whereas salt marsh (Great Brak 24.45 ha, East Kleinemonde 17.44 ha and Seekoei 12.9 ha) vegetation was dominant in the other estuaries. Despite the geographic differences, environmental factors influencing macrophyte distribution were similar in all estuaries. Canonical Correspondence Analysis showed that vegetation distribution was significantly affected by elevation, groundwater and sediment electrical conductivity and depth to groundwater. Supratidal species were associated with a greater depth to groundwater (1.2 ± 0.04 m; n = 153) compared to intertidal species (0.5 ± 0.01 m; n = 361). Correlation analysis showed that water level and rainfall were correlated with groundwater electrical conductivity in the lower and upper intertidal zones for all the estuaries sampled. These data indicate the influence of the estuary channel on the physico-chemical conditions of the salt marsh. Low rainfall (16 ± 3.3 mm per annum) in the Olifants Estuary (30-100 mS cm-1) and lack of freshwater flooding in the Kromme Estuary (42-115 mS cm-1) have resulted in high sediment electrical conductivity by comparison with the other estuaries sampled. In the Orange River Estuary approximately 70 ha of salt marsh have been lost through the building of a causeway and flood control levees. Even though salt marsh vegetation can tolerate hypersaline sediments by using the less saline water table, the groundwater at the Orange River Estuary was too saline (avg. of 90.3 ± 6.55 mS cm-1, n = 38) to be of use to the dominant floodplain species, Sarcocornia pillansii. Freshwater inflow to estuaries is important in maintaining longitudinal salinity gradients and reducing hypersaline conditions. In the Olifants Estuary and the Orange River Estuary where supratidal salt marsh is dominant, freshwater inflow is important in raising the water level and maintaining the depth to groundwater and salinity. Lack of freshwater inflow to the Kromme Estuary has highlighted the importance of rainfall in maintaining sediment salinity within acceptable ranges for the salt marsh. Macrophytes are relatively good indicators of physico-chemical factors in estuaries. From an understanding of the response of specific species to environmental variables, ecological water requirements can be set and sensitive areas can be rehabilitated.