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Macroinvertebrados bentônicos como indicadores da integridade de ecossistemas de água doce costeiros. Estudo de caso: lagoas do Parque das Dunas, Salvador, BA / Benthic macroinvertebrates as indicators of the health of coastal freshwater ecosystems. Case study: lakes of Parque das Dunas, Salvador, BASchiavone, Daniele Cristina 01 September 2014 (has links)
Lagoas costeiras, são corpos de água doce numerosos ao longo da costa brasileira, destacam-se principalmente como habitats para organismos aquáticos. São no entanto acossistemas sujeitos a grandes impactos antrópicos. No presente trabalho foram estudadas quatro lagoas costeiras da Área de Proteção Ambiental Parque das Dunas, em Salvador, Bahia, em dois períodos sazonais, chuvoso e seco, nos quais as lagoas foram comparadas. A comunidade de macroinvertebrados bentônicos foi utilizada como bioindicadora da qualidade ambiental. Dentre os organismos bentônicos, as larvas da família Chironomidae foram as mais frequentes e abundantes, sendo também estudada a dieta das mesmas com o objetivo de conhecer o papel desses organismos na estrutura e dinâmica trófica destas comunidades, através da observação de itens alimentares presentes no conteúdo de seus tubos digestivos. Os resultados da obtidos evidenciaram que as lagoas Vitória, Junco e Camarão tiveram águas com pH ácido, relativamente bem oxigenadas e de condutividade elétrica moderada em ambos os períodos amostrados. A riqueza de táxons foi moderada nas lagoas Vitória e Junco, variando de 13 a 21 táxons, e baixa nas lagoas do Camarão e Negra variando entre 8 e 14 táxons. Em relação à similaridade na composição das comunidades, as lagoas Vitória e do Camarão foram as mais semelhantes (50%), e a lagoa Negra a mais dissimilar (20%). Os indicadores utilizados evidenciaram que todas as lagoas estão perturbadas e necessitando ações de manejo, porém a Lagoa Negra deve ser priorizada quanto a ações de restauração. Em relação à ecologia trófica das larvas da família Chironomidae, os resultados evidenciaram o consumo de diversos itens alimentares como: algas, pequenos invertebrados, matéria orgânica amorfa e detrito particulado inorgânico. De acordo com o modo de alimentação e os itens consumidos, os diferentes táxons foram classificados em quatro grupos tróficos funcionais distintos: os Coletores - catadores detritívoros, o qual abrangeu a maioria dos gêneros de quironomídeos registrados nas lagoas; os Coletores- catadores herbívoros e os Predadores-onívoros, o qual abrangeu todos os gêneros de Tanypodinae e os Fragmentadores. Pode-se concluir que a onivoria é a provável estratégia que permite a coexistência de organismos de diferentes táxons aumentando assim a riqueza das larvas de Chironomidae nas lagoas costeiras avaliadas. / Coastal lakes are numerous freshwater bodies along Brazilian coast, being principally as habitats for the aquatic biota. They are nevertheless subject to great anthropogenic impacts. In the present work four coastal lakes located in the Protection Area of Parque das Dunas, in Salvador, Bahia, in two contrasting seasonal periods, the dry and the rainy periods, in which the lakes were compared. The benthic macro-invertebrates community was used as bio-indicator of environmental quality. Among the benthic organisms the dipteran larvae of the Chironomidae family were the most frequent and abundant. Their diet was also studied aiming to know the role of these organisms in the structure and trophic-dynamics of theses community by the analysis of the food items in their digestive tube. The results obtained have shown that lakes Vitória, Junco and Camarão had acidic, relatively well oxygenated and of moderate electrical conductivity waters in both periods sampled. The richness of taxa was moderate in lakes Vitória and Junco, varying from13 to 21 taxa, and low in lakes Camarão and Negra, varying between 8 and 14 taxa. Regarding the similarity among communities composition, lakes Vitória and Camarão were the most similar (50%), and Lake Negra the most different (20%). The indicators used evidenced that all lakes are under disturbances and require management actions, however, Lake Negra should be the priority for restauration actions. In relation to the trophic ecology of the Chironomidae larvae, the results evidenced the consumption of many food items as: algae, small invertebrates, decomposing organic matter, and particulate inorganic detritus. According to their feeding modes and consumed items the different taxa were classified in four distinct functional trophic groups: Collector-gatherer-detritivores, that comprised most chironomid taxa recorded in the coastal lakes; the Collector-gatherer-herbivores, the Predator-omnivores comprising all genera of the sub-family Tanypodinae and the Shredders. We concluded that probably omnivory is the strategy allowing the co-existence of organisms from many different taxa, being responsible for the richness of Chironomidae in the benthic communities of the studied coastal lakes.
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Paleolimnological Investigations From Modern Coastal Lakes On Thrace And Black Sea Coast Of Turkey During The Mid-late HoloceneSekeryapan, Ceran 01 September 2011 (has links) (PDF)
Here, we provide results of mid/late Holocene fresh water Ostracoda analyses from coastal modern lake basins in the Thrace region of Istanbul and Sarikum Lake, on the Black Sea coast near Sinop. While neither diatoms nor Cladocera are abundant in the sediments, Podocopian (fresh water) ostracods preserved well, but with discontinuous occurences during the mid/late Holocene. Un-noded forms of Cyprideis torosa, along with other Podocopian ostracods, dominated the sediments of all three lakes. Studying these three lagoonal basins along the Black Sea and Thracian coasts of Turkey allows reconstruction of long term, regional environmental histories, using the following methods. Loss-on-ignition (LOI) analyses at 1 cm intervals of short and long cores provide stratigraphic cross-correlation and calculations of organic matter, carbonate and mineral weight. At 5 cm intervals, spectrally-inferred chlorophyll-a contents by visible reflectance spectroscopy (Michelutti et al., 2010), provide estimates of algal production. Trace element analysis (Mg/Ca and Sr/Ca) using ICP-AES (coupled plasma atomic emission spectroscopy) is applied to fully calcified adult
specimens of un-noded forms of Cyprideis torosa shells (which dominate the uppermost 145 cm of Terkos Lake). 210Pb and 137Cs dating of short cores, and AMS 14C dating of long cores, are used to infer sediment accumulation rates and to place specific ages on inferred environmental changes. Benthic foraminifers, gastropods, bivalves, single valves of fossil Glochidia, and Charophyte seeds are the other biological indicators observed within the sediment archive. Based on these data: 1. Terkos Lake sediments contain records of multiple, sub-millennial scale marine incursion events, over the last 2.8 ka, inferred to be the result of severe storms or tsunami on the Black Sea, including the tsunami in AD 1598 and AD 557-543 / 2. short core sediments from Sarikum Lake reveal sharp decreases in organic matter, carbonate, and increases in algal production and sand amount that suggest a storm or more recent earthquake / such as the Great Erzincan Earthquake (26 December, 1939) or the Bartin earthquake (3 September, 1968) while four more such events appear in the undated sediments of the Sarikum Lake long core / and 3. a large earthquake in AD 447 that affected the entire Sea of Marmara (Leroy et al., 2002) does not appear in the Bü / yü / kç / ekmece Lake sediment record, but there is evidence for a significant hiatus in these deposits before the development of the dam (AD 1989) and after the youngest AMS date (2400 cal yrs BP). This suggests that Bü / yü / kç / ekmece Lagoon was an environment of net erosion prior to its artificial impoundment, either from gradual processes or from scouring by one or more tsunami.
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A mtDNA study of aspects of the recent evolutionary history and phylogeographic structure of selected teleosts in coastal environments of south-western Australiarhoddell@central.murdoch.edu.au, Richard James Hoddell January 2003 (has links)
At present, there is a general lack of information regarding the spatial genetic
architecture and genetic diversity of estuarine and coastal freshwater fish in
Australia or about the interacting intrinsic, extrinsic and historical influences
responsible for sculpting these patterns. This thesis represented the first
investigation of the phylogeographic structure and recent evolutionary histories
of teleost fishes from the coastal and estuarine environments of south-western
Australia, using the resolution afforded by mtDNA sequence data. Available
evidence indicated that, to different degrees, these species have limited
potential for dispersal amongst local assemblages from different water bodies.
As this theoretically reduces the confounding effects of recent gene flow on
extant genetic structure, these fishes were well suited to studying the
influences of historical factors. Historical influences were expected to be
particularly profound, given that these coastal environments underwent
massive modifications during Late Quaternary eustatic fluctuations.
The thesis consists of four major components, which explored different
aspects of interspecific and intraspecific phylogeny and p hylogeograp hy of
three teleost species, based on mtDNA control region and cytochrome b
fragments. First, the relationship between the endemic, 'strictly estuarine'
Leptatherina wallacei (Atherinidae) and the more widespread, 'estuarine &
marine' 6. presbyteroides was examined, with a view to establishing whether
6. wallacei represents a monophyletic or polyphyletic lineage and whether this
species was derived recently (i.e. in Holocene estuaries). Second, the
phylogeographic structure and genetic diversity of L. wallacei were investigated and compared with data from L. presbyteroides, with a view to
using this information to interpret the recent evolutionary histories of each
congener. Third, the divergence between assemblages of L. wallacei
inhabiting two isolated coastal lakes was used to estimate a maximal
substitution rate for the control region, which was then used to infer general
time frames for the divergence between the two Leptatherina species and
between the major phylogeographic partitions within each species. Fourth,
investigations were initiated into phylogeographic patterns and levels of
genetic diversity within and among assemblages of Pseudogobius olorum
(Gobiidae) from several coastal lakes and an estuary.
Phylogenetic analyses indicated that the two Leptatherina species were
characterised by exclusive and reciprocally-monophyletic lineages of
haplotypes from both mtDNA regions, supporting the monophyletic origins of
L. wallacei. Both 6. wallacei and 6. presbyteroides exhibited high levels of
genetic diversity and extensive overall subdivision (e.g. Qsr = 0.691 & 0.644
respectively for control region data). There was a profound phylogeographic
break in both species between all conspecific assemblages from the lower
west coast (LWC phylogroup) and all those from the south coast (SC
phylogroup), which suggested the influences of shared extrinsic and/or
historical factors. There was limited genetic structuring within the two major
phylogroups of either Leptatherina species, apparently reflecting recent
connectivity amongst local assemblages, with subsequent fragmentation and
insufficient time for lineage sorting. However, two major phylogeographic
breaks distinguished monophyletic control region phylogroups of L. wallacei from the isolated coastal Lake Clifton and Lake Walyungup, consistent with
their independent evolution following lacustrine entrapment during the
Holocene.
The divergence between these two isolated lacustrine assemblages of
Leptatherina wallaceiformed the basis for an estimate of the maximal
substitution rate of the control region. While these data were unable to
provide a precise estimate of the actual rate of molecular evolution, all the
evidence suggested that it was proceeding very rapidly. The maximal rate
estimate of 172.3% lineage-' MY-' was among the fastest ever reported.
Based on this rate, the two Leptatherina species diverged at least 1 SKya, thus
rejecting a Holocene origin for L. wallacei. The divergence between the LWC
and SC phylogroups of L. wallacei has been ongoing for at least GKya, while
the equivalent divergence in L. presbyteroides has been ongoing for at least
11 Kya. As the time frames of these divergences were consistent with periods
of massive environmental modifications associated with the end-Pleistocene
fall in sea level and the HMT, it was likely that these factors have played
important roles in sculpting the species' divergence and intra-specific genetic
structure. Although useful in temporally scaling genetic divergences within
and between the two Leptatherina species, wider application of this rate
estimate to questions regarding other taxa was limited. For example, evident
rate heterogeneity between the genera precluded its use with even the
relatively closely-related atherinid Atherinosoma elongafa.
Phylogeographic analyses identified high levels of genetic diversity and
extensive genetic subdivision (e.g. st = 0.652 for control region) amongst an
estuarine and several lacustrine assemblages of Pseudogobius olorum,
although phylogeographic structure was shallower than in either Leptatherina
species. There was increased divergence between three assemblages from
the lower west coast and two from the south coast, consistent with the
profound break evident in the Leptatherina. One lacustrine assemblage
appeared to represent a distinct lineage and a preliminary maximal rate
estimate (~61.4% lineage-1 MY-1) was calculated based on the minimum
divergence of this assemblage from its nearest conspecifics. Although slower
than the rate calculated for L. wallacei, this was still high for teleost fishes.
Overall, this study indicated that historical environmental factors, especially
those related to Quaternary eustatic changes, have played important roles in
sculpting the phylogeography and evolution of three teleost species from
south-western Australia. Moreover, as these species have differential
dependencies on estuarine environments (is. 'strictly estuarine' vs 'estuarine
& marine') and represented two different taxonomic groups (i.e. Atherinoidei &
Gobioidei), historical environmental factors may have exerted similar
influences on other coastal species in the region.
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Macroinvertebrados bentônicos como indicadores da integridade de ecossistemas de água doce costeiros. Estudo de caso: lagoas do Parque das Dunas, Salvador, BA / Benthic macroinvertebrates as indicators of the health of coastal freshwater ecosystems. Case study: lakes of Parque das Dunas, Salvador, BADaniele Cristina Schiavone 01 September 2014 (has links)
Lagoas costeiras, são corpos de água doce numerosos ao longo da costa brasileira, destacam-se principalmente como habitats para organismos aquáticos. São no entanto acossistemas sujeitos a grandes impactos antrópicos. No presente trabalho foram estudadas quatro lagoas costeiras da Área de Proteção Ambiental Parque das Dunas, em Salvador, Bahia, em dois períodos sazonais, chuvoso e seco, nos quais as lagoas foram comparadas. A comunidade de macroinvertebrados bentônicos foi utilizada como bioindicadora da qualidade ambiental. Dentre os organismos bentônicos, as larvas da família Chironomidae foram as mais frequentes e abundantes, sendo também estudada a dieta das mesmas com o objetivo de conhecer o papel desses organismos na estrutura e dinâmica trófica destas comunidades, através da observação de itens alimentares presentes no conteúdo de seus tubos digestivos. Os resultados da obtidos evidenciaram que as lagoas Vitória, Junco e Camarão tiveram águas com pH ácido, relativamente bem oxigenadas e de condutividade elétrica moderada em ambos os períodos amostrados. A riqueza de táxons foi moderada nas lagoas Vitória e Junco, variando de 13 a 21 táxons, e baixa nas lagoas do Camarão e Negra variando entre 8 e 14 táxons. Em relação à similaridade na composição das comunidades, as lagoas Vitória e do Camarão foram as mais semelhantes (50%), e a lagoa Negra a mais dissimilar (20%). Os indicadores utilizados evidenciaram que todas as lagoas estão perturbadas e necessitando ações de manejo, porém a Lagoa Negra deve ser priorizada quanto a ações de restauração. Em relação à ecologia trófica das larvas da família Chironomidae, os resultados evidenciaram o consumo de diversos itens alimentares como: algas, pequenos invertebrados, matéria orgânica amorfa e detrito particulado inorgânico. De acordo com o modo de alimentação e os itens consumidos, os diferentes táxons foram classificados em quatro grupos tróficos funcionais distintos: os Coletores - catadores detritívoros, o qual abrangeu a maioria dos gêneros de quironomídeos registrados nas lagoas; os Coletores- catadores herbívoros e os Predadores-onívoros, o qual abrangeu todos os gêneros de Tanypodinae e os Fragmentadores. Pode-se concluir que a onivoria é a provável estratégia que permite a coexistência de organismos de diferentes táxons aumentando assim a riqueza das larvas de Chironomidae nas lagoas costeiras avaliadas. / Coastal lakes are numerous freshwater bodies along Brazilian coast, being principally as habitats for the aquatic biota. They are nevertheless subject to great anthropogenic impacts. In the present work four coastal lakes located in the Protection Area of Parque das Dunas, in Salvador, Bahia, in two contrasting seasonal periods, the dry and the rainy periods, in which the lakes were compared. The benthic macro-invertebrates community was used as bio-indicator of environmental quality. Among the benthic organisms the dipteran larvae of the Chironomidae family were the most frequent and abundant. Their diet was also studied aiming to know the role of these organisms in the structure and trophic-dynamics of theses community by the analysis of the food items in their digestive tube. The results obtained have shown that lakes Vitória, Junco and Camarão had acidic, relatively well oxygenated and of moderate electrical conductivity waters in both periods sampled. The richness of taxa was moderate in lakes Vitória and Junco, varying from13 to 21 taxa, and low in lakes Camarão and Negra, varying between 8 and 14 taxa. Regarding the similarity among communities composition, lakes Vitória and Camarão were the most similar (50%), and Lake Negra the most different (20%). The indicators used evidenced that all lakes are under disturbances and require management actions, however, Lake Negra should be the priority for restauration actions. In relation to the trophic ecology of the Chironomidae larvae, the results evidenced the consumption of many food items as: algae, small invertebrates, decomposing organic matter, and particulate inorganic detritus. According to their feeding modes and consumed items the different taxa were classified in four distinct functional trophic groups: Collector-gatherer-detritivores, that comprised most chironomid taxa recorded in the coastal lakes; the Collector-gatherer-herbivores, the Predator-omnivores comprising all genera of the sub-family Tanypodinae and the Shredders. We concluded that probably omnivory is the strategy allowing the co-existence of organisms from many different taxa, being responsible for the richness of Chironomidae in the benthic communities of the studied coastal lakes.
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Numerical Study on Hydrodynamics and Sediment Transport of Shallow Coastal Lagoons / 浅い沿岸ラグーンの水理現象と土砂輸送に関する数値解析的研究Mohamed Reda Mohamed Mahmoud Soliman 24 September 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第17865号 / 工博第3774号 / 新制||工||1577(附属図書館) / 30685 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 牛島 省, 教授 角 哲也, 准教授 米山 望 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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AlteraÃÃes morfolÃgicas e capacidade de suporte ambiental da lagoa costeira do catÃ, Aquiraz, CearÃ, Brasil / Morphological changes and environmental support capacity of the coastal lagoon CatÃ, Aquiraz, CearÃ, BrazilLysandra Guedes Fontenele 06 January 2014 (has links)
A utilizaÃÃo dos recursos hÃdricos em suas mais distintas formas vem acarretando sÃrios impactos negativos para os reservatÃrios, tanto na exploraÃÃo de suas Ãguas quanto na ocupaÃÃo dos seus entornos. A lagoa costeira do Catà està localizada no municÃpio de Aquiraz-CE, caracteriza-se pela elevada beleza cÃnica, pelos atrativos turÃsticos e pela crescente especulaÃÃo imobiliÃria. A ocupaÃÃo indevida das Ãreas de ProteÃÃo Permanente (APPs) vem acarretando uma sÃrie de impactos ambientais negativos para a lagoa. O presente estudo teve por base estudar as alteraÃÃes morfolÃgicas e sedimentolÃgicas associadas aos impactos ambientais da Lagoa do CatÃ, em decorrÃncia do uso e ocupaÃÃo da sua bacia de contribuiÃÃo, verificando as mudanÃas ao longo dos Ãltimos 10 (dez) anos (2003 - 2013). Para tanto, utilizou-se mapeamento de imagens dos anos de 2007 e 2012 para a identificaÃÃo das atividades de uso e ocupaÃÃo da lagoa e de sua bacia de contribuiÃÃo direta, estimativas de contribuiÃÃo de sedimento das diversas atividades econÃmicas e da cobertura do solo e procedimentos de batimetria atual e comparativa ao ano de 2003, caracterizaÃÃo sedimentolÃgica de 49 amostras do fundo lacustre e relacionamento dos dados de contribuiÃÃo de sedimento com a ocupaÃÃo das APPs. Verificou-se que a bacia de contribuiÃÃo da lagoa à uma Ãrea fortemente influenciada pelos fatores naturais, a exemplo do Ãndice pluviomÃtrico da regiÃo e das atividades exercidas no seu entorno. Quanto a comparaÃÃo do relevo submerso atual com o ano de 2003, observou-se a variaÃÃo do nÃvel das profundidades, identificando um decrÃscimo de 2 metros, assim como a pontualizaÃÃo das maiores profundidades na porÃÃo ao norte da lagoa e das menores na dimensÃo mÃdia e nas suas margens, fato explicado pela constante movimentaÃÃo de sedimentos provenientes das mais diversas atividades. Por meio do mapeamento da regiÃo em anos distintos verificou-se o acrÃscimo e decrÃscimo de diversas classes de usos a nÃvel de Ãrea. Para as estimativas de sedimento as principais atividades que contribuem sÃo: Ãrea descampada, Dunas-paleodunas-planÃcie de deflaÃÃo, faixa de praia e Ãrea urbana. Quanto as caracterÃsticas sedimentolÃgicas hà uma predominÃncia da classe arenosa, principalmente de sedimentos finos e em seguida pela fraÃÃo lamosa. O sistema lagunar possui baixa energia ao norte, e de sul à porÃÃo mÃdia da lagoa hà considerÃvel energia. A geoquÃmica para o ambiente indicou valores baixos de carbonato de cÃlcio no geral, com picos em Ãreas com atividades urbanas intensas. Para os Ãndices de matÃria orgÃnica foram encontradas as maiores quantidades na porÃÃo ao sul, regiÃo caracterizada pela forte aÃÃo antrÃpica. Notou-se a supressÃo de grande parte da APP, sendo possÃvel relacionar os pontos com mais contribuiÃÃes de sedimentos e cargas
geoquÃmicas em Ãreas desprovidas de vegetaÃÃo peculiar. AlÃm das vulnerabilidades sujeitas ao ambiente, como as ameaÃas de cheias quando em perÃodos chuvosos, assoreamento em diversas porÃÃes dado as atividades urbanas com contribuiÃÃes para os processos erosivos por meio das diversas construÃÃes e aterramentos. / Hydric resources using in it most different ways have been causing serious negative impacts for its depots, not only in its water exploration, but also in its borders occupation. Catà coastal lake is located in the city of Aquiraz, CearÃ, and itâs characterized by elevated scenic beauty, touristic attractives and increasing real estate speculation. The incorrect occupation of the Permanent Protection Areas (PPAs) is causing a series of serious negative impacts to the lake. This research has in its base the study of the morphological alterations in Catà coastal lake in recurrence of its contribution bay using and occupation, and also verifies its environmental support capacity by using its invested sediment cargo, verifying its changes by the last ten years (2003 â 2013), by image mapping of years 2007 and 2012 for identification of using and occupation activities of the lake and its direct contribution bay, sediment contribution estimation of various economical activities and soil covering and actual and comparative bathymetry procedures in the year of 2003, sediment characterization of 49 samples of lacustrine soil, and data relation of sediment contribution and with PPAs occupation. The identified characteristics belong to the bay as a natural factor influenced area, as instanced by the region pluviometric index and the man-made activities by the borders. As for the comparing of the actual submerged relief with the year of 2003, the biggest observed alteration was the deep level with the decreasing of 2 centimeters, as well as the pointing of the deepest areas in the north of the lake, and the smallest in the medium dimension and its borders, fact explained by the constant sediment moving originated from the most different activities. By the region mapping in different years, it was verified the increasing and decreasing of several using classes in an area level. For the sediment estimate, the most contributing activities are: wildness area, deflation-planed-paleaodunic Dunes, Beach Stripe and Urban Area. As for the sediment characteristics, there is a dominance of sandy class,
mostly thin sediments, followed by muddy fraction. The estuarine system has low energy by the downstream, and upward at medium portion thereâs a considerable high energy. Geochemistry for the ambient has indicated low calcium carbonate values in general, with peaks in intense urban activities areas. For organic material index, the highest quantities were found by the south portion, a region with strong man-made action. It was noted the suppression of a biggest area of the PPA, being able to determine the points with more sediment contribution and geochemical cargos in areas without peculiar vegetation. Aside the environment vulnerabilities, like the floods in rainy periods, aggradations in different portions caused by urban activities with contributions for erosive process by different buildings and aggradations.
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