Made available in DSpace on 2014-06-11T19:30:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-10-23Bitstream added on 2014-06-13T18:40:09Z : No. of bitstreams: 1 nirchiot_m_dr_botib.pdf: 4765215 bytes, checksum: 3816626c8d8ca5d5c260dac1dfc0f0ef (MD5) / Diploid number (2n), Karyotype formula and the fundamental number (NF) for 94 fish species, 68 marine and 26 freshwater species from 39 families contained in 18 orders revealed that the diploid number ranged between 2n = 24 in Mugil curema (Mugilidae) and 2n=60 for Pygocentrus cariba, Serrasalmus rhombeus (Characidae) and Hoplosternum littorale (Callichthyidae) with a mode of 48 chromosomes represented in 47.3% (43/92) of all studied species. The percentage of species with exclusively 48 acrocentric chromosomes was 29.67% (27/91) and the NF ranged from 33-34 in Stephanolepis setiter (Tetraodontiformes) to 110 in Pygocentrus cariba and Serrasalmus rhombeus (Characiformes). In the marine fish group the mbdal diploid number was 48 and was represented in 66.6% of all studied species, whereas in the freshwater fishes modal diploid complement was 2n=54 represented in 30% of the studied species. The median of the number of chromosomes was statistically higher in freshwater fishes than saltwater fishes. The NF was higher in the group of freshwater fishes indicating that the degree of karyotipic variation was greater in fish of inland waters in contrast with a more conserved cytogenetic pattern in the marine fishes. The proportion of species with 48 exclusively acrocentric chromosomes predominated in 36.7% of the marine fishes while it barely reached 7.7% in freshwater fishes. Comparing the Perciformes (a lineage composed mainly of marine fish and one of the most derived in the Actinoperygii phylogeny of the) against the rest of the orders, it was verified that in Perciformes 61.54% of analyzed species exhibited karyotypes with 48 chromosomes. When diploid number of chromosomes and the NF were plotted against the phylogenetic arrangement proposed by NELSON (2006) for actinopterigian fishes, both plottings revealed an inversely proportional relationship with values close to 60 in most ancestral... (Complete abstract click electronic access below) / La determinación del numero diploide (2n), la fórmula cariotípica y el Número Fundamental (NF) para 68 especies marinas y 26 dulceacuícolas pertenecientes a 39 familias contenidas en 18 ordenes reveló que el número diploide varió entre 2n=24 en Mugil curema (Mugilidae) y 2n=60 para Pygocentrus cariba, Serrasalmus rhombeus (Characidae) y Hoplosternum littorale (Callichthyidae) con una moda de 48 cromosomas representada en 47,3% (43/91) de todas las especies estudiadas. El porcentaje de especies que posee exclusivamente 48 cromosomas acrocéntricos (a) fue de 29,67% (27/91) y el NF varió entre 33/34 en Stephanolepis setifer (Tetraodontiformes) a 110 en Pygocentrus cariba y Serrasalmus rhombeus (Characiformes). En el grupo de peces marinos, el número diploide modal fue 48 y estuvo representado en 66,6% de todas las especies estudiadas, mientras que en los peces dulceacuícolas el complemento diploide modal fue 2n=54 representado en 30% de las especies estudiadas. La mediana del número de cromosomas fue estadísticamente mayor en los peces dulceacuícolas que en los marinos. EI el range medio del NF fue superior en el grupo de peces dulceacuícolas indicando que el grade de variación cariotípica, fue mayor en peces de aguas continentales en contraste con un patrón citogenético más conservado en los peces marinos. La proporción de especies con 48 cromosomas exclusivamente acrocéntricos predominó en el 36,7% de los peces marinos mientras que en los dulceacuícolas apenas alcanzó el 7,7%. Al comparar los Perciformes (linaje compuesto principalmente por peces marinos y uno de los más derivados en la filogenia de los Actinoperygii) contra el resto de los órdenes, se verificó que en aquellos, el 61,54% de las especies analizadas exhibieron cariotipos con 48 cromosomas a. AI graficar el número diploide de cromosomas y el NF contra la ordenación filogenética propuesta... (Resumen completo clicar acceso eletronico abajo)

Made available in DSpace on 2014-10-09T12:28:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:29Z (GMT). No. of bitstreams: 0 / Em outubro de 2005 a notificação de 17 casos de doença ocular de etiologia desconhecida, envolvendo, em sua maioria, a população infantil da cidade de Araguatins/TO, levou as autoridades locais a pedirem ajuda a Secretaria de Estado da Saúde do Estado do Tocantins no intuito de descobrirem sua etiologia, tratamento e prevenção. Nos pacientes acometidos, os sinais freqüentemente observados foram: intensa hiperemia conjutival, granuloma, episclerite, infiltrado corneano periférico. Na anamnese realizada nos pacientes foi observado que todos tiveram contato com as águas do Rio Araguaia. Os resultados obtidos a partir do processamento das amostras de água, sedimentos e substratos particularmente na vegetação marginal inundada, permitiram confirmar a hipótese de que deveria haver uma fauna rica de esponjas no Araguaia, no trecho fronteiro à cidade de Araguatins A presença intraocular de espícula de esponja de água doce das espécies Drulia uruguayensis e Oncosclera navicela foi confirmada em material avaliado histopatologicamente proveniente de três pacientes que haviam sido submetidos a lensectomia, sugerindo que espículas de água doce poderiam ser um surpreendente novo agente etiológico de patologia ocular. Assim, neste estudo foram realizados ensaios de citotoxicidade com amostras de duas espécies de esponjas coletadas no local. Os resultados indicam que os extratos das esponjas após filtração em filtro Millipore 0,45 μm continuaram apresentando atividade citotóxica, sugerindo haver um componente SOLÚVEL, e não somente espículas, capaz de induzir morte celular na população de células utilizadas. Os indivíduos acometidos foram na maioria do sexo masculino com idade entre 05 e 14 anos. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:50:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:03Z (GMT). No. of bitstreams: 1 00385.pdf: 917455 bytes, checksum: 170691f120f1bd5b66fa48cba02fe1f6 (MD5) / Dissertacao (Mestrado) / IEA/D / Escola Politecnica, Universidade de Sao Paulo - POLI/USP

INTRODUÇÃO: A urbanização em bacias hidrográficas contribui para a eutrofização antrópica dos seus corpos d´água, propiciando proliferações de algas tóxicas como as cianobactérias. Existe um padrão característico de sazonalidade nas florações de algas e comunidades de cianobactérias, embora estas algas possam estar presentes ou mesmo dominantes, na maior parte do ano, trazendo problemas práticos associados à elevada biomassa de cianobactérias e potenciais ameaças à saúde pelo aumento de toxinas. A hipótese desta tese é de que as variações do tempo e do clima podem influenciar a qualidade da água de abastecimento ao propiciar florações das algas tóxicas, cianobactérias, que geram toxinas dificilmente filtradas pelos mecanismos comuns, gerando um problema de saúde pública que pode ser agravado com as mudanças climáticas conjuntamente o fenômeno de urbanização crescente nos países de economia emergente. OBJETIVO: O objetivo deste estudo foi investigar qual a influência do tempo e do clima na qualidade da água de abastecimento público de bacias urbanizadas através do indicador de algas tóxicas chamadas cianobactérias. MATERIAL E MÉTODOS: Para tanto investigou-se em primeiro lugar qual o contexto das proliferações de cianobactérias em reservatório de abastecimento público e suas consequências bem como qual o estado da arte sobre a qualidade da água de reservatórios eutrofizados em bacias urbanizadas, foi elaborado um mapeamento bibliográfico para saber qual a extensão do problema e do que se sabe a respeito. E, por fim, correlacionou-se a influência do tempo e do clima na qualidade da água para abastecimento no caso da bacia urbanizada da Represa Guarapiranga, localizada ao sul da Cidade de São Paulo, com vistas à previsibilidade e prevenção do fenômeno das florações das cianobactérias. RESULTADOS E DISCUSSÃO: Chegando-se a conclusão de que a pressão antrópica e o uso do solo são um fator determinante para a eutrofização de reservatórios de abastecimento e que, por tanto, bacias hidrológicas ocupadas pelo espraiamento urbano são particularmente propensas a apresentar reservatórios de água contaminados com algas toxicas, ao mesmo tempo que são as mais visadas para abastecer a população em seu entorno. O mapeamento bibliográfico mostrou que a proliferação de cianotoxinas em reservatórios eutrofizados é prevalente em diferentes latitudes e climas. A modelagem de correlação teve sucesso em explicar de 16% à 30% das florações na Guarapiranga de acordo com episódios de Irradiação e de precipitação pluviométrica, sendo resultados coerentes com a literatura, embora sejam baixo para gerar um modelo preditivo. CONSIDERAÇÕES FINAIS: A pressão antrópica da urbanização de bacias hidrográficas sem planejamento ou infra-estrura sanitária se mostrou uma questão de Saúde Pública e Saúde Urbana. As florações de cianobactérias se apresentaram como fenômenos presentes em diferentes latitudes, climas e graus de organização do espaço, mostrando assim serem uma questão global de saúde pública. A modelagem para o caso de São Paulo resultou em valores de explicação insuficientes para gerar um modelo preditivo do fenômeno das florações, evidenciando o sistema complexo de interação ambiente-ocupação humana-uso do solo- clima, exigindo assim que sejam acrescentadas demais variáveis ao modelo. / INTRODUCTION: Urbanization in hydrographic basins contributes to the anthropic eutrophication of their water bodies, propitiating toxic algae proliferation such as cyanobacterias. There is a characteristic pattern of seasonality in algae blooms and cyanobacteria communities, although theses algae may be present or even dominant during most part of the year. They cause practical problems associated with high biomass volumes, and potential health threats by the rise of toxins. This thesis\' hypothesis is that weather and climate variations can influence the quality of drinking water supply, because toxins are hardly filtered by ordinary mechanisms. The problem can be aggravated by climate change conjointly with the rapid widespread of urbanization in low and middle income countries. OBJECTIVE: This study\'s aim was to investigate the influence of weather and climate variables on the quality of water from the public drinking water supply system of an urbanized watershed through the indicator of toxic algae - denominated cyanobacterias. MATERIALS AND METHODS: First, the cyanobacterias\' blooms in eutrophic reservoir and its\' consequences, was studied by literature review and by an exploratory analysis of monthy weather varables and cyanobacterias data. Secondly, a bibliographical mapping review was drafted in order to know the extension of the problem and what is known regarding it. Finally, data of weather and climate were correlated with the quality of supple water of the, Guarapiranga reservoir, located on the south of São Paulo metropolitan area, acknowledging predictability and prevention of the phenomenon of cyanobacteria bloom. FINDINGS AND DISCUSSION: The conclusion was that the anthropic pressure and land use are determinant factors to the eutrophication of supply reservoir and, therefore, hydrological basins occupied by urban sprawling are particularly at risk of presenting water reservoirs contaminated with toxic algae. They are the most targeted to supply water to their neighbor population. The bibliographic mapping showed that the proliferation of cyanotoxins in eutrophized reservoirs is prevalent in different latitudes and climates. The correlation modeling was successful in explaining 16% to 30% of blooms in Guarapiranga according to episodes of irradiation and low precipitation, matching results found in literature, although they are low for the creation of a predicative model. FINAL CONSIDERATIONS: The anthropic pressure of urbanization on hydrographic basins without planning or sanitary infrastructure guidelines was shown to be a matter of public and urban health. Cyanobacterias\' blooms was shown to be a phenomena present in different latitudes, climates and degrees of space organization, proving to be a matter of global public health. The modeling for the case of São Paulo has resulted in insufficient explanation values to generate a predictive model of the phenomena of flowering, indicating the complex interaction system involving environment, human occupation, land use and climate, and demanding that more variables be acknowledged in the model.

With the rising influence of digitalization and its immense penetration intoeven everyday life, the last decade of the 20th Century addressed to a critical threshold in the successive transformation process of the spatiality in its long-term run. The advanced digital technologies of ubiquitous computing and generative design, as well as the invention of smart materials in late 90’s (particularly the nano-technological materials that emerged as the programmable matters with their ability to evolve continously) have all provoked the fluid characteristics of spatiality, and strengthen the transformative capacities of the architectural space through the emergence of computer-augmented territories. Additionally, while they are becoming as the body extensions, the advent of novel apparatuses and gadgets further enhanced the inte- gration of the corporal and incorporal bodies with the spatio-temporal multiplicities, where the hyperdimensionality of the space has been triggered to its outmost range, in relation to the “soft and smart technologically augmented immanent millieu”, in Spuybroek terms. Thus, like Spuybroek points out as the “haptonomist” presence of the body merges itself with these diverse bodily extensions on one hand; and on the other hand, as the rising influence of nomadic view of the world further stimulates the unboundedness and endless fluidity of space, so that the spatiality becomes a landscape of successive transformations, a topology of emergence or a plane of becoming, which is merely defined by lines of forces, and occures as an alive territory rather than a limited space of predefined boarders. Therefore, this evolvable territory which is affectable and being affected by the lines of forces –inner and outer forces–, emerges as an animated existence, an interactive organism. So, by interacting with the Deleuzian Philosophy and their notions like lines of forces, folding, becoming, smooth space, territory, spatium, this article aims to reveal the relevance of these notions in architectural discourse, as well as the emergence of the smooth space in the contemporary architectural practice, by magnifiying one of the very initial examples of its kind; in terms of unfolding the Fresh Water Pavilion of NOX Architecture by Lars Spuybroek into question to reveal the essences of thecontemporary transformable-evolvable architectural spatiality.

The Arctic is a hotspot of global change. For example, changes caused by global warming are both amplified and are seen more rapidly in the Arctic (e.g., Serreze & Francis, 2006; Bekryaev et al., 2010; Serreze & Barry, 2011; Overland et al. 2015; Macdonald et al., 2015). Thus, the Arctic is an indicator of the state of the planet. Among the strongest changes that have been observed in the Arctic Ocean are changes in circulation regimes, hydrographic properties and freshwater content and composition. These changes have the potential of global impact through interaction with the deep-water formation regions of the North Atlantic Ocean, a major source of deep and bottom water in the global ocean. Although significant progress in understanding the signals of change in the Arctic Ocean and their causes has been made during the past decades there are still some fundamental questions unanswered. They include the stability of the circulation of the upper waters and changes in the freshwater budget and how these changes are connected to changes in the composition of the freshwater lens that covers the Arctic Ocean. In this thesis, we address these two topics using measurements of isotopes obtained during over three decades of Arctic Ocean section work.This dissertation is composed by three parts and its structure mimics the layered vertical structure of the Arctic Ocean water column. Chapter 1 is dedicated to the Atlantic waters, Chapter 2 to the halocline waters, and Chapter 3 to the freshwater sources and their distribution and variability in the surface layer. In the first two chapters, we present transient tracer (³H/³He) and hydrographic data from over 25 years of Arctic oceanographic campaign ranging from 1987 to 2013 to evaluate flow rates and circulation pathways in the Upper Halocline Water (UHW), Lower Halocline Water (LHW), and Atlantic Layer on a pan-Arctic scale. In agreement with previously established circulation schemes, tracer data show that the flow paths in the LHW and the Atlantic layer are typically topographically steered with the presence of a cyclonic boundary current along the continental shelf and separate circulation branches tracking major bathymetric features, such as the Lomonosov Ridge. Tracer data suggest that the general circulation of UHW is decoupled from the cyclonic regime observed in the deeper layer, and strongly influenced by surface stress forcing, such as the anticyclonic Beaufort Gyre. Within the limits of our method, tracer data show that the mean flow paths and spreading velocities have been more or less constant over the past three decades despite dramatic shifts in the Arctic system heat and freshwater balances from anthropogenic climate change over imposed to a high natural variability. The third and final chapter discusses the water-mass composition and the distribution of freshwater sources in Canadian Basin, the western section of the Arctic Ocean. Results are produced by performing a water-mass decomposition on the water samples collected during the 2015 Arctic GEOTRACES (GN01) oceanographic expedition. Stable isotope measurements (H₂¹⁸O/H₂¹⁶O and DHO/H₂O ratios) are used in combination with salinity and nutrients data to calculate the water-mass components for the upper 500 m Arctic Ocean (mixed layer through Atlantic Water layer). The sources of liquid freshwater into the Arctic Ocean include Pacific water, sea ice meltwater, river discharge and net precipitation. The topmost 50 meters of Canadian Basin contain the large fraction of freshwater from sea ice meltwater and meteoric water. Pacific water dominated the freshwater budget along the 2015 GN01 transects from 100 to 250 m. These depths are also characterized by a strong brine rejection signal, reflecting an enhanced annual sea ice cycle with more ice refreezing and melting each year, and an overall loss of multiyear ice. The 2015 results are compared with the overlapping 1994 and 2005 Arctic Ocean Sections (AOS94 and AOS05) and discussed in the context of regional and temporal variability of liquid freshwater and its components distribution. Our findings show significant increases in the Canadian Basin total liquid freshwater reservoir both compared to the 1994 and 2005 transects confirming a freshwater accumulation in the Canadian Basin already established by numerous observations and modeling studies (Gilles et al., 2012; Carmack et al., 2016; Proshutinsky et al. 2019; Solomon et al., 2021). The total freshwater reservoir increased by ca. 12,500 km³ from 1994 to 2015, of which ca. 5,000 km3 are within the Beaufort Gyre. Meteoric and Pacific freshwater components were the largest sources of the observed freshwater accumulation in the upper 500m of the western Arctic Ocean. An intensified Ekman transport in the Beaufort Gyre and increased availability of freshwater for accumulation are the two primary drivers for freshwater accumulation in the Canadian Basin. Within the limits of our analysis, it is not possible to quantitatively estimate the relative importance of the each forcing nor to resolve the seasonal to year‐to‐year variability. Our tracer-based analysis suggests that there is a significant variability in the freshwater components and UHL distribution while the major features of the circulation patterns and spreading velocities of the AW and the LHW have remained largely stable over the past decades. Future research should address whether in a fast changing Arctic, the dynamics of the surface layer will expand to the halocline and Atlantic layer substantially destabilizing the current Arctic Ocean water column with potentially dramatic consequences.

Large-scale circulation in the northern North Atlantic plays a crucial role in the global climate by influencing ocean storage of atmospheric heat and carbon. Temperature and salinity changes in this region can have important consequences on ocean circulation due to density stratification at sites of deep water formation. Such influences can involve feedback mechanisms related to the Atlantic Meridional Overturning Circulation, which has been shown to influence the hydrography of the northern North Atlantic on decadal timescales. Current expectations are that through increasing sea-ice melting, river discharge, an intensifying hydrological cycle and glacial melt anomalies, future climate change could disrupt North Atlantic circulation patterns with cascading effects on carbon cycling and global climate. These interactions were investigated through circulation changes associated with salinity and freshwater variability, as well as variability in temperature and heat content. Recent changes in phytoplankton concentration and biological productivity in the Labrador Sea were also examined as part of this study. Spatial and temporal patterns of salinity in the North Atlantic were examined with the help of objective analysis and reanalysis salinity products using Argo observations of the recent decade (2005 to 2015). An overall freshening trend was evident, but with clear regional differences, particularly between the western subpolar gyre and the central North Atlantic. In general, the western subpolar region exhibited high interannual variability in surface salinity compared to the central North Atlantic. The western subpolar region also revealed a seasonal pattern of salinity fluctuation related to sea ice retreat and accretion, but with some years (i.e., 2008, 2012 and 2015) showing unusually large and negative salinity anomalies which were not present in the central or eastern North Atlantic. To understand the dominant factors influencing salinity and freshwater in the northern North Atlantic, budgets for liquid freshwater content over the northern North Atlantic were derived using a state-of-the-art ocean state estimate (ECCOv4). Here the subpolar North Atlantic (between $\sim$45\oN and the Greenland Scotland ridge) is distinguished from the Nordic Seas (north of the Greenland Scotland ridge). In a separate investigation ECCOv4 was used to describe global ocean heat budgets at varying spatial and temporal resolutions. This analysis showed that anomalies in temperature tendency are driven by atmospheric forcing at short time scales, while advection is the principle term at long time scales. ECCOv4 budget analysis was then used to investigate mechanisms behind interannual freshwater content variability in the northern North Atlantic over the time period 1992-2015. From the mid-1990s to the mid-2000s warming and salinification occurred in the subpolar North Atlantic. Consistent with the upper layer analysis with Argo-observations, ECCOv4 confirmed an overall freshening since about 2005. This freshening occurs simultaneously with an overall cooling in the subpolar North Atlantic. Advective convergence has been identified as the dominant driver of liquid freshwater content and ocean heat content variability in the subpolar North Atlantic, with liquid freshwater and heat content being anti-correlated. Consistent with the global heat analysis in ECCOv4, our results revealed that forcing is only important for establishing anomalies over shorter time scales (i.e., seasonal to interannual), but advective convergence becomes more important at longer (i.e., decadal) scales. Advection is the dominant term due to changes across the southern boundary on the decadal time scale, while exchanges with the Arctic Ocean have minor impact. Changes in freshwater and heat content in the subpolar North Atlantic due to advection occur through anomalies in the circulation itself, and not by the advection of anomalies in either liquid freshwater or heat content. In contrast to the subpolar North Atlantic, in the Nordic Seas interannual changes in liquid freshwater content are predominantly driven by forcing due to sea ice melting, which is in turn strongly correlated with Arctic sea ice export through Fram Strait. The overall concurrent warming and salinification followed by cooling and freshening in the subpolar North Atlantic suggests a relationship with changes in northward heat and salt transport through the Atlantic Meridional Overturning Circulation. This is consistent with decadal variability in deep convection in the Labrador Sea. It is evident that another consequence of changes in the Labrador Sea deep convection is the potential effects on nutrient availability and thus biological productivity. The Labrador Sea has become more productive in recent years, with mean chlorophyll-a concentrations closely correlated with silicate concentrations in the upper waters, which in turn are strongly correlated with wintertime convection depth. Thus annual production in the Labrador Sea appears to be influenced by the extent of deep winter mixing, thereby linking the Atlantic Meridional Overturning Circulation and deep convection to nutrient availability and ocean productivity in the subpolar North Atlantic.

The aim of this study is to gain a better understanding of how agricultural activities in rice cultivation areas in southern Brazil’s Pampas biome in affect biodiversity. Aquatic insects and water parameters such as pH, oxidation reduction potential (ORP), dissolved oxygen and conductivity are used as bioindicators and are measured in field sampling and analyzed in laboratory studies. Research questions have been used to further discuss how water near rice cultivation areas and sustainable agriculture should be used for the future. Three different sampling points were used for the study, organic (OR) rice fields, conventional (CON) rice fields and natural wetlands (NA). Results show no significant influence of nitrogen on the insect richness or abundance, nitrite shows significant influence but not enough to draw any strong conclusions from the result. Water parameters with the highest correlation to the insect community in this study are pH, ORP, conductivity and total dissolved solids. Both the measured pH value and ORP are strongly correlated to the chemical status of the water and the insects that live there. Too high or too low pH value is not favorable for aquatic insects or the waters biodiversity, nor a too low value of ORP. Results could not show a significant difference among the aquatic insect composition between the three measured sampling sites. Although when measuring difference in insect composition, values from PERMANOA and NMDS indicates that the measured organic areas have a higher similarity to the natural areas than the conventional areas. This study is strongly linked to a sustainable development and Agenda 2030s goal 4 and 15 since biodiversity is a fundamental thing on this earth and needs to be preserved.

A shortage of shell resources for restoring reefs of the Eastern oyster, Crassostrea virginica, has led to widespread use of substitute materials. The effectiveness of such alternative substrates as habitat for reef-associated fauna other than oysters is largely unresolved. I investigated the habitat value of oyster shell, surf clam (Spisula solidissima) shell, and pelletized coal ash reefs for benthic and nektonic communities. Oyster recruitment, survival, and growth were monitored on reefs of oyster and surf clam shell near the mouth of Chesapeake Bay and York River, USA. Oyster shell supported greater oyster growth and survival and offered the highest degree of structural complexity. On the York River subtidal clam shell reef, the quality of substrate varied with reef elevation. Oysters were more abundant and larger at the reef base and less abundant and smaller on the crest. The availability of interstitial space and appropriate settlement surfaces likely accounts for observed differences in oyster abundance across reef systems. These patterns give further context to the importance of substrate selection in restoration activities. Invertebrate fauna associated with oyster shell, clam shell, and pelletized coal ash reefs were investigated. Diversity and production were greatest on oyster shell reef. Species richness was lowest on coal ash; however, total community abundance was significantly greater than on the other reef types. Clam shell reefs showed intermediate abundance and diversity patterns but had the lowest values for production. Nekton abundance, diversity, and community structure between reef types were measured. Data show differences in community structure across habitat types. Species richness was greatest on oyster shell and coal ash. Significant differences in nekton presence and abundance between oyster and clam shell reefs were detected. Clam shell reefs were similar in species composition and abundance to a beach habitat. These reef habitats are refuges, as demonstrated by the transient nekton species that dominated all habitats. Oyster shell and coal ash reefs served as habitat to many ecologically, commercially, and recreationally important species, providing food and shelter during juvenile life stages, and suggest reef habitats are of great importance as habitat to finfish communities.

Vitellogenin (VTG) is widely used as a biomarker for environmental estrogens and reproductive disruption in fish. Vitellogenesis is the process by which yolk is formed. The endpoint is most sensitive in male fish where vitellogenesis is an abnormal process. Research examining effects of environmental mixtures of chemicals (e.g. creosote) on vitellogenesis is limited. This study examines plasma VTG expression in both male and female mummichog, Fundulus heteroclitus, collected from a creosote-contaminated site and two reference sites in lower Chesapeake Bay, USA, and in wild-caught male reference fish exposed in the laboratory to creosote-contaminated sediment. Further, this study uses tissue somatic indices (gonadosomatic index, hepatosomatic index, and condition factor) as organ-level indicators of reproductive status and creosote exposure. Western blotting with an anti-vitellogenin monoclonal antibody (FY 10- 9) was used to identify an abundant (approx. 218 kDa) protein in F. heteroclitus plasma samples. Vitellogenin was not observed in any male fish collected from any of the field sites. No sitespecific differences were observed in plasma VTG of females from these sites. Overall, fish from the creosote-contaminated site appear resilient and reproductively fit. After seven days of exposure, reference fish exposed to sediment from the creosote-contaminated site suffered extensive mortality (approx. 25% ), but displayed no expression of VTG and had no alterations in other measured indices except for increased hepatosomatic index and induction of the biotransformation enzyme, cytochrome P4501A (CYPlA). Lack of response in Atlantic Wood fish could be due to: (1) physiological adaptation of the population from the creosotecontaminated site to creosote exposure (2) species-specific sensitivity (3) creosote not exerting estrogenic effects and regulating vitellogenesis. Thus, while VTG has been used successfully as a practical and reliable screening method for wildlife toxicity, results herein do not support use of this biomarker for F. heteroclitus from creosote-contaminated sites. This study does reaffirm constituents of creosote binding to the aryl hydrocarbon receptor resulting in induction of CYP IA. More attention needs to be given to developing alternative biomarkers not sensitive to aryl hydrocarbon-mediated antiestrogens if detection of weak estrogens and reproductive disruption in creosote and other complex mixtures is to be achieved.