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Biologia populacional do poliqueta exogone (exogone) breviantennata Hartmann-Schröder, 1959 (Syllidae: Exogoninae) / Population biology of the polychaete exogone (exogone) breviantennata Hartmann-Schröder, 1959 (Syllidae: Exogoninae)Nagai, Micael Eiji, 1983- 20 August 2018 (has links)
Orientador: Antonia Cecília Zacagnini Amaral / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T07:27:07Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: O estudo do silídeo Exogone (Exogone) breviantennata foi realizado em dois bancos de Mytella charruana (sururu) nas praias do Camaroeiro e da Cidade, localizadas na enseada de Caraguatatuba, Litoral Norte de São Paulo. Para caracterizar as áreas de estudo foram realizadas amostragens mensais, entre fevereiro de 2006 e fevereiro de 2007, no Camaroeiro, e entre abril de 2006 e março de 2007, na Cidade, e avaliados os parâmetros ambientais: perfil praial, granulometria, temperaturas do ar e do sedimento, salinidade da água intersticial e teores de calcário e matéria orgânica. O perfil praial do Camaroeiro apresentou uma declividade acentuada desde o supralitoral, terminando em uma pequena planície no nível d'água; a praia da Cidade apresentou um extenso platô na região superior e em seguida um declive contínuo. A composição granulométrica dos dois bancos foi semelhante, com predominância de areia fina, pobre a moderadamente selecionada. As temperaturas médias do ar e do sedimento no banco do Camaroeiro foram de 23,08°C e 23,73°C, respectivamente, e na Cidade de 22,55°C e 23,98°C, respectivamente. As áreas médias dos bancos do Camaroeiro e da Cidade foram de 586,73 m2 e de 464,48 m2, respectivamente. Em ambos os bancos houve uma diminuição gradual na área. No banco do Camaroeiro a salinidade da água intersticial variou de 22 a 34, enquanto na Cidade de 25 a 34. O teor médio de calcário no banco do Camaroeiro apresentou uma variação de 3,74 a 11,99%, já na Cidade foi de 5,55 a 14,30%. O teor médio de matéria orgânica apresentou valor mínimo de 0,74 % e máximo de 8,40% no Camaroeiro, enquanto na Cidade foi de 2,62% e 7,98% / Abstract: The study of the syllid Exogone (Exogone) breviantennata was conducted in two soft bottom beds of the mytilid Mytella charruana at Camaroeiro and Cidade beaches, located on the northern coast of São Paulo. To characterize the study areas, samples were taken monthly between february 2006 and february 2007 at Camaroeiro, and between april 2006 and april 2007 at Cidade, where the following environmental parameters were analyzed: beach slope, granulometry, air and sediment temperatures, interstitial salinity and levels of calcareous and organic matter. The beach slope of Camaroeiro showed a sharp decline from the supralitoral, ending with a narrow flat at water level, with processes of deposition and erosion; the Cidade beach presented an extensive plateau at the upper region and then a sharp decline, with erosion as the main process. The granulometric composition of the two beds was very similar, with a predominance of fine sand, with low to moderate selection. The average air and sediment temperatures at Camaroeiro were 23.08°C and 23.73°C, respectively, while in the Cidade was 22.55°C and 23.98°C, respectively. The mean areas of the Camaroeiro and Cidade beds were 586.73 m² and 464.48 m², respectively. On both beds there were gradual decreases in these areas. At Camaroeiro the interstitial salinity ranged from 22 to 34, while at Cidade from 25 to 34. The average percentage of calcareous on the Camaroeiro bed showed a variation from 3.74 to 11.99%, while on the Cidade bed it ranged from 5.55 to 14.30%. The average percentage of organic matter presented minimum and maximum of 0.74% to 8.40% at Camaroeiro, while the Cidade bed presented 2.62% and 7.98% / Mestrado / Ecologia / Mestre em Ecologia
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Benthic assemblage structure, and the feeding biology of sixteen macroinvertebrate taxa from the Buffalo River, Eastern Cape, South AfricaPalmer, C G (Carolyn Gay) January 1992 (has links)
The River continuum concept (RCC) (Vannote et al. 1980) attempted to provide a unifying theory of river function. The Functional Feeding Group (FFG) concept (Cummins 1973, 1974) became a major component of the RCC. The FFG concept provides testable hypotheses about the changes in proportions of FFGs along a downstream gradient in a river, in response to the changing nature of food resources. The following short-comings of the FFG concept have been identified: 1) the variability of macroinvertebrate feeding, 2) problems with gut analysis as a method for assigning taxa to FFGs, and 3) inconsistent criteria defining FFGs. The objective of this study was to investigate the macroinvertebrate fauna of the Buffalo River in order to assess the applicability of aspects of the RCC and the FFG concept. The specific aims of the study were: 1) to describe the distribution of macroinvertebrate assemblages in the Buffalo River; 2) to clarify aspects of the FFG concept listed above; 3) to establish whether selected taxa could be assigned to FFGs; 4) to assess whether the proportions of different FFGs in successive reaches of a southern African river conformed to the predictions of the RCC; and 5) to test whether a functional classification is a useful alternative to a taxonomic classification. Macroinvertebrates were collected seasonally from a variety of biotopes at three sites, one each in the upper, middle and lower reaches. Riffles were sampled in summer at 16 sites. Over 100 taxa were identified and an hierarchical classification was prepared using two-way indicator species analysis. Invertebrate assemblages in the narrow headwater stream were taxonomically distinct from those of the middle/lower reaches and were not positively associated with subjectively identified biotopes. Biotopes were characterised by distinct assemblages in the wider middle/lower reaches. Sixteen abundant taxa whose feeding had not been previously investigated were selected for feeding studies, four from the headwaters and 12 from the middle/lower reaches. Methods used included gut content analysis, behavioural observations, food choice experiments and morphological studies using scanning electron microscopy. Three aspects of the functional feeding group concept were clarified. 1) Dietary variability was assessed using gut contents as an index of diet. The gut contents of both early (small) and late (large) instar larvae of all 16 taxa collected from different sites and biotopes, and in different seasons were compared using a multifactor analysis of variance. For all taxa the most consistently significant differences in gut contents were between large and small larvae. These were due to differences in the amount of material in the gut and in varying amounts of rarer dietary items. Dietary variability did not prevent taxa from being assigned to FFGs. 2) Gut content analysis satisfactorily provided basic information about the feeding biology of taxa but proved to be an inadequate single method for positively assigning taxa to FFGs. 3) Before taxa could be assigned to FFGs the definitions for some FFG categories had to be described clearly. It is suggested that the term shredder be based on the observation of shredding and a predominance of leaf fragments in the foregut. The presence of algae was not diagnostic of scrapers and a morphological basis is suggested. A morphological basis for the brusher FFG is described for the first time. All 16 taxa were assigned to FFGs. Three headwater taxa were shredders ((Goerodes caffrariae (Lepidostomatidae), Dyschimus ensifer (Pisulidae), Afronemoura spp. (Notonemouridae)) and one was a collector:brusher (Adenophlebia auriculata (Leptophlebiidae). These results were consistent with RCC predictions. All 12 of the taxa from the middle/lower reaches were filterers or collectors and this result was also consistent with RCC predictions. The Hydropsychidae, Cheumtopsyche afra and Macrostemum capense, were passive net filterers; Neurocaenis reticulatus (Tricorythidae) was a passive setal filterer; Caenidae sp. Band Pseudocloeon maculosum (Baetidae) were active filterers; caenidae sp. A, and the Baetidae, Baetis harrisoni, Centroptilum excisum and Cloeon africanum, were collector: gatherers; the Leptophlebiidae, Choroterpes elegans and Choroterpes nigrescens, were collector:brushers; and Afronurus harrisoni (Heptageniidae) was a scraper. Gut content analyses alone were insufficient to assign taxa to FFGs, but when augmented by morphological and/or behavioural data, taxa could be assigned to FFGs with confidence. In all cases the FFG designation referred to the most frequent style of feeding. N. reticulatus, A. harrisoni and A. auriculata were particularly flexible in their feeding behaviour. A functional classification of macro invertebrates in the Buffalo River was compared with a taxonomic classification. In both cases similar groups were identified, but their taxonomic and functional descriptions yielded different information. It is suggested that functional and taxonomic classifications should be viewed as complementary rather than alternative options.
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Mesozooplankton dynamics in a biogeographical transition zone estuaryDeyzel, (Shaun) Herklaas Phillipus January 2012 (has links)
This thesis presents the first intensive community-level investigation of the mesozooplankton from a biogeographical transition zone estuary. The Mgazana Estuary is located along a rural, semi-undeveloped part of South Africa’s east coast, believed to represent a transition zone between the subtropical and warm-temperate biogeographical zones. The research represented in this thesis involves data collected over a five year period between 2002 and 2006, with additional data collection made in 2008. The study focussed on five areas of investigation, the first of which investigated the physico-chemical dynamics of the Mgazana Estuary. The Mgazana Estuary exhibited marked vertical, horizontal and regional structures in the hydrological environment. Prominent vertical and horizontal stratification characterised summer months. A substantial turbidity front was observed in the lower estuary during summer and winter. The upper estuary was marked by considerable variation in multiple variables but especially salinity. These structures appeared to have shifted in position over the horizontal plane, which was attributed to variation in freshwater flow. The second study focused on the spatial dynamics of mesozooplankton in the Mgazana Estuary. The zooplankton was rich and in terms of composition typical of mangrove systems. The Copepoda were dominant, numerically and in terms of taxonomic representation. Calanoids Acartiella natalensis and Pseudodiaptomus hessei characterised middle and upper reaches in summer and mostly upper reaches in winter. On community level, a highly structured assemblage arrangement was observed during summer and winter months. These trends were further scrutinised under the theoretical framework of ecological boundaries. In so doing, an agreeable spatial association emerged between specific assemblages and their environments. These trends were concluded to reflect ecoclinal as well as ecotonal properties, the latter describing interactions over narrow spatial bands of marked changes in turbidity. The third study investigated flooding events as short-lived extreme meteorological events and the influence on zooplankton. Within this regard, second-stage multivariate statistics was used to assess year-to-year variability in assemblage structures on whole-system and regional scales. The impact of two major flooding events that flushed the estuary some days prior to sampling could clearly be elucidated. Flooding emerged as a significant source of inter-annual variability in the zooplankton of the Mgazana Estuary. Second-stage multivariate analysis proved to be an effective analytical strategy for investigating inter-annual variability in species assemblage structures. Results from the preceding study prompted a detailed investigation into the spatio-temporal dynamics of Acartiella natalensis, the most important zooplankton species of the system aimed at elucidating flood responses. Acartiella natalensis showed indication of temporal arrest in association with flooding events in a similar fashion as is observed in seasonal variation trends in estuaries towards its geographical distribution limit south of the study area. It was concluded that A. natalensis was severely affected by floods and the possibility exist for entrainment of entire populations from the estuary during flooding events. The final study tested the hypothesis of post-flood propagation from a resting egg bank in the sediments of the Mgazana Estuary. Preliminary data revealed that numerous eggs were present in the sediments. Nauplii hatched from eggs under laboratory conditions were identified as belonging to the family Acartiidae. The preliminary mode of diapause is presented as a schematic model, emphasising the role of freshwater flow and specific environmental variables. This was the first discovery of resting eggs from a subtropical estuary from South Africa. It is hoped that the findings of this study would give rise to new research initiatives investigating the importance of resting stages in estuarine and coastal Copepoda species and the role such reproductive strategies may play in estuarine functioning.
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Biodiversidade dos Echinodermata da Baía do Araçá, São Sebastião, SP / Biodiversity of Echinoderms from Araçá Bay, São Sebastião, SPAlitto, Renata Aparecida dos Santos, 1986- 27 August 2018 (has links)
Orientador: Michela Borges / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T05:03:51Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015 / Resumo: Com o propósito de estudar a biodiversidade dos Echinodermata da Baía do Araçá, São Sebastião (SP), foi analisado o material procedente do Projeto Biota/FAPESP- "Biodiversidade e funcionamento de um ecossistema costeiro subtropical: subsídios para gestão integrada", Proc. nº 2011/50317-5. Para avaliação da diversidade e densidade desses organismos foram realizados: (i) inventário dos Echinodermata; (ii) estudos taxonômicos morfológicos com descrições detalhadas e discussões específicas para Ophiuroidea, incluindo ilustrações e fotomicrografias das espécies e ampliação das descrições já existentes e (iii) estudo dos fatores que influenciam a riqueza e abundância desses animais em microescala. Os equinodermos foram amostrados na região entremarés até 23 m de profundidade, costões rochosos, e como fauna associada a esponjas. Dos 863 exemplares coletados, foram identificadas quatro classes, 13 famílias, 19 gêneros e 25 espécies, o que corresponde a 8,3 % dos equinodermos registrados para o litoral brasileiro. A classe Ophiuroidea foi a mais diversa com 16 espécies e duas delas representam novos registros para a Baía: Amphiura kinbergi e Ophiothela danae. Para as espécies de ofiuróides, foi realizado um estudo taxonômico mais aprofundado com descrições da morfologia externa e interna (ossículos braquiais), o que enriqueceu as descrições já existentes. A maior riqueza e abundância deste grupo foi verificada no infralitoral quando coletado com draga. Amphiuridae e Ophiactidae foram as famílias mais representativas e corresponderam a aproximadamente 80 % do total de ofiuróides amostrado. Os resultados obtidos com esse trabalho contribuirão de forma consistente para o conhecimento da biodiversidade dos equinodermos no Estado de São Paulo, será a base para futuros monitoramentos sobre o impacto das atividades humanas na baía e seu entorno e contribuirá para implementações de ações de conservação deste rico ambiente / Abstract: The aim of the present work is to study the biodiversity of Echinodermata from Araçá Bay, São Sebastião (SP). We analyzed the material from Biota Project / FAPESP - "Biodiversity and functioning of a subtropical coastal ecosystem: a contribution to integrated management", Proc. No 2011 / 50317-5. Diversity and density avaliations of these organisms were performed to: (i) build an inventory of Echinodermata; (ii) morphological taxonomic studies with detailed descriptions and specific discussions to Ophiuroidea, including illustrations and photomicrographs of species and expansion of existing descriptions and (iii) study the factors that influence the richness and abundance in microscale. The echinoderms were sampled in the intertidal zone to 23 m deep, rocky shores, and as associated fauna of sponges. The 863 specimens collected were classified into four classes, 13 families, 19 genera and 25 species, corresponding to 8.3 % of echinoderms registered for the Brazilian coast. The Ophiuroidea was the most diverse with 16, with two being are new records for the Araçá Bay: Amphiura kinbergi and Ophiothela danae. For species of brittle stars, there was a further taxonomic study with descriptions of external and internal morphology (arm ossicles), that enriched the existing descriptions. The highest richness and diversity of this group was observed in infralitoral when collected with a dredge. Amphiuridae and Ophiactidae were the most representative brittle stars families and accounted for approximately 80 % of brittle stars sampled. The results of this work will contribute consistently to the knowledge of the echinoderms diversity in São Paulo, will be the basis for future monitoring of the human activities impact on the bay will contribute to this rich conservation actions implementations environment / Mestrado / Biodiversidade Animal / Mestra em Biologia Animal
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Bottom Fauna of Lake WorthJenkins, Jesse Denney 08 1900 (has links)
This thesis describes the vertical distribution, quality, and quantity of the fauna found at the bottom of Lake Worth in Texas.
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Experimental studies of interactions between Zostera marina and the associated benthic faunaPenny, David Marshall 01 January 1978 (has links)
The objectives of the present study are to: (1) Describe the macro-invertebrate species composition and seasonal changes in abundance of the benthic infauna within an eelgrass bed; (2) Observe what immediate effects occur to the benthic community as a result of experimental removal of eelgrass plants from plants within the Zostera bed; (3) Measure the seasonal variation of eelgrass turion length over an annual cycle and determine its correlation to biomass (dry weight); (4) Examine, by means of field experiments, the importance of incident solar irradiation in affecting the seasonal growth of Zostera; and (5) Determine the relationship, if any, between the abundance of major invertebrate species and the abundance of eelgrass as determined by mean turion length.
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Responses of macrobenthic communities to pollution control and fisheries management measures in Hong KongWang, Zhi 30 August 2019 (has links)
Benthic animals have been widely used as health indicators of the marine benthic ecosystems in temperate regions. My PhD thesis mainly aimed to understand the responses of benthic ecosystem in tropical Hong Kong waters to the two management measures - pollution control and trawling ban. My study was based on sediment grab samples collected from 28 stations in three territory-wide surveys conducted in 2001, 2012 and 2015 in Hong Kong waters. I compared the spatial and temporal changes in macrobenthic community structure as well as physical and chemical characteristics of benthic habitats between surveys conducted before and after the pollution control measures in 2001 and 2012, as well as surveys before and after the fishery management measure in 2012 and 2015. The impacts of sewage pollution to benthic ecosystems had been noted in many studies, which included deteriorated water quality and bottom sediment, and disturbed, less diverse macrobenthic community dominated by opportunistic small-sized species. Therefore, sewage treatment and cessation of sewage effluent discharge were expected to lead to notable improvement in benthic habitats, biodiversity and macrobenthic communities; besides, responses of benthic ecosystems to pollution control may be hydrologically varied. In Hong Kong, a series of sewage treatment schemes, e.g. Stage 1 of Harbour Area Treatment Scheme (HATS), Tolo Harbour Action Plan (THAP), Tolo Harbour Effluent Export Scheme (THEES) and a number of sewage treatment works had been conducted in different areas of Hong Kong. Changes in the community structure were noted in the three focal areas with pollution control measures, i.e. Victoria Harbour, Deep Bay and Tolo Harbour; while apparent recoveries were noted inside the Victoria Harbour, the changes in benthic communities inside the Tolo Harbour and Deep Bay could not be attributed to the pollution control measures. Specifically, a decline in nutrient input to the eastern part of Victoria Harbour due to the implementation of HATS might have led to declined sedimentary total organic matter and the disappearance of the opportunistic species, and hence a recovery of benthic ecosystem therein. But in the sheltered Tolo Harbour and Deep Bay, neither improvement in sediment quality nor biodiversity were noted, thus indicating a longer duration is needed for the recovery of benthic ecosystems to take place in these land-locked bays. Degraded marine fishery resources and destruction in marine ecosystems had been noted since the introduction of modern trawling vessels had into Hong Kong since the 1950s and 1960s. Currently, most reports of benthic ecosystem responses to cessation of trawling originate from temperate regions, while it is not well understood for the situation in tropical areas. The territory-wide trawling ban in tropical Hong Kong waters was implemented by the Hong Kong government since December 31, 2012. Although improvement in benthic ecosystems was anticipated after the ban, it was unknown when this would happen and how different parts of the Hong Kong waters would respond to the trawling ban. My study showed that, around 3 years after the trawling ban, sedimentary organic matter content had increased significantly, and bottom water suspended solid loads had decreased in most of the survey stations, indicating territory-wide improvement in the benthic environment. Moreover, significant increases in richness, abundance and functional diversity of macrobenthos, as well as a more aggregated, fewer but larger station groups of macrobenthic communities were also detected after the trawling ban, indicating rapid recovery of the benthic communities. In conclusion, my study indicates that benthic communities in tropical Hong Kong can be used as bioindicators of environmental changes. Due to their restricted mobility, benthic organisms should be an integral part of the ecosystem monitoring aiming to detect the consequences of management measures to the marine environment. Environmental data including habitat complexity and hydrology are also required to fully understand the spatial and temporal dynamics of benthic ecosystems. Besides, my study has provided two territory-wide baseline data on the biodiversity and macrobenthic community structure in the tropical Hong Kong waters, which will be valuable for detecting future changes in the benthic ecosystems. My benthic ecology studies have resulted in a published paper and a manuscript ready for submission for publication. Besides focusing on benthic ecology, I have conducted taxonomic studies on benthic polychaetes, resulting in two published papers. As good taxonomy is the basis of high-quality data in benthic ecology, the training I received from studying these benthic polychaetes has enhanced my understanding of the biology of benthos, which is also important for my career development. However, since these papers do not fall into the main theme of my thesis, they are included in the thesis as appendixes only.
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An assessment of electrofishing at different conductivities as a collection method for stream invertebrates / En bedömning av elfiske vid olika konduktiviteter som en insamlingsmetod för ryggradslösa djurBorgiel, Björn January 2020 (has links)
Electrofishing is a commonly used method to capture fish, but not as frequently used for collecting invertebrates, so-called “electrobugging”. It is well known that electrofishing has a negative effect on some organismss, but not many studies have investigated how invertebrates, e.g. invertebrate larvae are affected. There is no knowledge of whether the larva is damaged or killed by electrofishing. Some larvae can be used assess water quality. A measurement of how polluted freshwater is, the three orders Ephemeroptera, Plecoptera and Trichoptera (EPT) are used, which are very sensitive to pollution and eutrophication in running water. When electrofishing you need to adapt the method due to the water, where an important parameter is the conductivity. In this study, an investigation on how EPT is affected by two different conductivities 15.7 and 25.0 mS/m. How EPT is affected by the catching methods kick sampling and electrobugging. As well as whether there is a difference in catch efficiency between electrobugging and kick sampling depending on the different orders being captured. In this study, the conductivity tests were conducted in a laboratory and the comparison of the two catch methods and catch efficiency were conducted in field. It was 12.5 % of EPT which died in control and 2.5 % died of electrobugging in the two different conductivities. In kick samples, the delayed mortality was higher in the order Trichoptera (31%) than in Ephemeroptera (21%). Water conductivity has no effect on the extent to which EPT is affected by electrobugging at 400V. Only Ephemeroptera is more adversely affected by electrobugging than by kick sampling as a collection method. There is a difference in catch efficiency between electrobugging and kick sampling regarding the order that is caught. / Elfiske är en vanlig metod för att samla in fiskar, men används inte lika ofta för att samla in evertebrater, så kallad ”electrobugging”. Att elfiske påverkar en del organismer negativt är känt men det är inte så många studier som undersökt hur evertebrater t.ex. sländor, påverkas. Det saknas kunskap om huruvida sländorna skadas eller dör till följd av elfisket. Några sländeordningar kan användas för att tala om hur vattnet mår. Ett mått på hur förorenat sötvatten är så används de tre ordningarna Ephemeroptera, Plecoptera, och Trichoptera (EPT) vilka är väldigt känsliga för föroreningar och övergödning i rinnandevatten. När man elfiskar behöver man anpassa metoden efter vattnet, där en viktig parameter är konduktiviteten. I denna studie undersöktes hur EPT påverkas av två olika konduktiviteter 15,7 och 25,0 mS/m. Hur EPT påverkas av fångstmetoderna sparkprov och electrobugging. Samt om det finns en skillnad i fångsteffektivitet mellan electrobugging och sparkprover beroende på vilka olika ordningar som fångas. I denna studie gjordes test på konduktivitet i labb och jämförelsen av de två fångstmetoderna och fångsteffektiviteten i fält. Det var 12,5 % av EPT som dog i kontroll och 2,5 % dog av electrobugging i de två olika konduktiviteterna. I sparkprover var den fördröjda dödligheten högre hos Trichoptera (31%) än hos Ephemeroptera (21 %). Vattnets konduktivitet har inte någon betydelse i för i vilken utsträckning EPT påverkas av electrobugging vid 400V. Det är endast Ephemeroptera som påverkas mer negativt av electrobugging än av sparkprover som insamlingsmetod. Det finns en skillnad i fångsteffektivitet mellan electrobugging och sparkprover gällande vilka ordningar man fångar.
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THE ROLE OF WAVE DISTURBANCE ON LENTIC, BENTHIC ALGAL COMMUNITY STRUCTURE AND DIVERSITYThomas, Evan William 04 May 2007 (has links)
No description available.
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RELATIONSHIP BETWEEN LAND USE, HABITAT, AND AQUATIC BENTHIC INVERTEBRATE COMMUNITIES IN TROPICAL MONTANE FORESTSJustus, Savannah 16 May 2017 (has links)
No description available.
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