Dissertations / Theses: 'Faunal assemblages'

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Marshall, Jonathan Coid, and n/a. "Factors Influencing the Composition of Faunal Assemblages in Rainforest Stream Pools." Griffith University. Australian School of Environmental Studies, 2001. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040218.150407.

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Previous research has shown that a range of physical and biological drivers can influence the composition of faunal assemblages occupying localities within streams. There is much debate in the literature about which of these is more important. Descriptive and experimental field studies were conducted in two relatively undisturbed, second order rainforest streams in southeast Queensland, Australia. The principal objectives were to describe spatial and temporal patterns in pool fauna and explore relationships between these patterns and physical attributes of habitat, disturbance and biotic interactions. The macroinvertebrate and vertebrate fauna of 12 small stream pools were sampled approximately monthly over a period of 15 months. Samples were collected from all major within-pool habitat types and concurrent measurements of potentially important environmental parameters were made at landscape scales of stream, pool and habitat patch. Faunal assemblages were consistently different between the two streams and between the various within-pool habitat types, although the latter may partially be explained by differences in sampling protocols applied in the different habitat types. However, spatial and temporal variation in faunal assemblages within habitat types was large at the scales of whole pools and within-pool habitats, and this variation occurred apparently independently of variation in physical habitat attributes. These results indicated that very little of the local scale faunal variation could be explained by abiotic drivers and that some other factors must be responsible for the observed faunal patterns. Previous research had indicated that atyid shrimps can play a significant ecological role in rainforest streams, where they act as 'ecosystem engineers' by removing fine sediment from hard surfaces. This subsequently alters algal dynamics and faunal composition in streams. A pool-scale manipulative experiment was conducted to investigate the role of the atyid Paratya australiensis, which is an abundant and conspicuous component of the fauna. Removal of shrimp from pools had no effect on sediment accrual on hard surfaces and consequently did not affect algal biomass or faunal assemblages. The lack of effect on sediment accumulation was attributed to the low rate of deposition in these streams, which was an order of magnitude lower than in streams where atyids have been demonstrated to play a keystone role. The fish Mogurnda adspersa was found to be the primary predator of pool fauna in the study streams, where it preyed on a wide variety of taxa. Dietary analyses revealed that an ontogenetic shift occurred in both diet and the within-pool habitat where fish fed. Within this general framework, individual fish had strong individual prey preferences. Significant correlations were found between the natural abundance of Mogurnda in pools and faunal assemblage patterns in both gravel habitat and pools in general, indicating that predation had an effect on pool fauna. The nature of this effect varied between habitats. A direct density dependent response was observed in gravel habitat. In contrast, the response in pools varied considerably between individual pools, perhaps reflecting the differing prey preferences of individual fish. Despite these correlations, an experimental manipulation of the density of Mogurnda at a whole-pool scale did not conclusively identify a predation effect. This may have been due to problems with fish moving between treatments, despite attempts to constrain them, and low experimental power due to the inherent high variability of pool fauna. Overall, the results of the study indicated that there was considerable spatial and temporal variation in pool fauna despite similarities in the physical attributes of pools and their close proximity. This variation appeared to occur at random and could not be explained by abiotic or biotic factors. Predation had a small effect, but could not explain the overall patterns, whereas disturbance by spates had very little effect at all. Stochastic processes associated with low level random recruitment were identified as a possible and plausible explanation for observed patterns. These conclusions are discussed in terms of their implications for our understanding of the ecology and management of streams.

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Marshall, Jonathan Coid. "Factors Influencing the Composition of Faunal Assemblages in Rainforest Stream Pools." Thesis, Griffith University, 2003. http://hdl.handle.net/10072/366983.

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Previous research has shown that a range of physical and biological drivers can influence the composition of faunal assemblages occupying localities within streams. There is much debate in the literature about which of these is more important. Descriptive and experimental field studies were conducted in two relatively undisturbed, second order rainforest streams in southeast Queensland, Australia. The principal objectives were to describe spatial and temporal patterns in pool fauna and explore relationships between these patterns and physical attributes of habitat, disturbance and biotic interactions. The macroinvertebrate and vertebrate fauna of 12 small stream pools were sampled approximately monthly over a period of 15 months. Samples were collected from all major within-pool habitat types and concurrent measurements of potentially important environmental parameters were made at landscape scales of stream, pool and habitat patch. Faunal assemblages were consistently different between the two streams and between the various within-pool habitat types, although the latter may partially be explained by differences in sampling protocols applied in the different habitat types. However, spatial and temporal variation in faunal assemblages within habitat types was large at the scales of whole pools and within-pool habitats, and this variation occurred apparently independently of variation in physical habitat attributes. These results indicated that very little of the local scale faunal variation could be explained by abiotic drivers and that some other factors must be responsible for the observed faunal patterns. Previous research had indicated that atyid shrimps can play a significant ecological role in rainforest streams, where they act as 'ecosystem engineers' by removing fine sediment from hard surfaces. This subsequently alters algal dynamics and faunal composition in streams. A pool-scale manipulative experiment was conducted to investigate the role of the atyid Paratya australiensis, which is an abundant and conspicuous component of the fauna. Removal of shrimp from pools had no effect on sediment accrual on hard surfaces and consequently did not affect algal biomass or faunal assemblages. The lack of effect on sediment accumulation was attributed to the low rate of deposition in these streams, which was an order of magnitude lower than in streams where atyids have been demonstrated to play a keystone role. The fish Mogurnda adspersa was found to be the primary predator of pool fauna in the study streams, where it preyed on a wide variety of taxa. Dietary analyses revealed that an ontogenetic shift occurred in both diet and the within-pool habitat where fish fed. Within this general framework, individual fish had strong individual prey preferences. Significant correlations were found between the natural abundance of Mogurnda in pools and faunal assemblage patterns in both gravel habitat and pools in general, indicating that predation had an effect on pool fauna. The nature of this effect varied between habitats. A direct density dependent response was observed in gravel habitat. In contrast, the response in pools varied considerably between individual pools, perhaps reflecting the differing prey preferences of individual fish. Despite these correlations, an experimental manipulation of the density of Mogurnda at a whole-pool scale did not conclusively identify a predation effect. This may have been due to problems with fish moving between treatments, despite attempts to constrain them, and low experimental power due to the inherent high variability of pool fauna. Overall, the results of the study indicated that there was considerable spatial and temporal variation in pool fauna despite similarities in the physical attributes of pools and their close proximity. This variation appeared to occur at random and could not be explained by abiotic or biotic factors. Predation had a small effect, but could not explain the overall patterns, whereas disturbance by spates had very little effect at all. Stochastic processes associated with low level random recruitment were identified as a possible and plausible explanation for observed patterns. These conclusions are discussed in terms of their implications for our understanding of the ecology and management of streams. Thesis (PhD Doctorate) Doctor of Philosophy (PhD) Australian School of Environmental Studies Full Text

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Palmer, Denise D. "Late Holocene planktic foraminiferal assemblages from Orca Basin : effects of dissolution on faunal assemblages." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001693.

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Scott, K. "British bone caves : a taphonomic study of Devensian faunal assemblages." Thesis, University of Cambridge, 1986. https://www.repository.cam.ac.uk/handle/1810/273094.

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Hambleton, Ellen. "A comparative study of faunal assemblages from British Iron Age sites." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4646/.

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The broad aim of this thesis is to further understanding of British Iron Age animal husbandry regimes by undertaking a comparative study of faunal assemblages. More specifically, this involves development of a uniform methodology for comparing published faunal data in order to recognise inter and intra-regional patterns of animal husbandry. Lack of uniformity in methods of recording and presenting faunal data, together with variation in the quality and quantity of information published in reports, serves as a barrier to systematic quantitative comparison. This thesis therefore seeks to develop methods of comparison which utilise the most commonly available forms of faunal data, or convert different forms of data into a single comparable format, in order that inter and intra-regional analyses of the widest possible dataset can be undertaken. To ensure viable comparisons unaffected by small sample bias, only those sites with total cattle, sheep and pig assemblages of NISP>300 or MNI>30 are included in this study. Analyses concentrate on the three main domestic species (cattle, sheep, and pig) which comprise the bulk of all faunal remains recovered from excavations of British Iron Age sites, and utilise three main types of information: Firstly, representation of different skeletal elements is examined in order to recognise the effects of taphonomic and human alteration on each assemblage. Secondly, quantification data for cattle, sheep, and pig is compared, using tripolar graphs to establish the relative importance of different species in each assemblage. Thirdly, mandibular tooth wear data is used for the composition of mortality profiles to compare herd management strategies. Both species proportions and mortality profiles from different faunal assemblages are compared, and examined for any inter and intra-regional similarities. Subsequently assemblages are examined for relationships between patterns of species proportions and/or mortality profiles and particular site characteristics (topographical location, underlying geology, settlement type, and date). Finally, using the results of these analyses, suggestions are made as to the nature of animal husbandry regimes in different regions, and the factors influencing choice of husbandry strategy in Iron Age Britain.

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Tweedley, James. "Relationships between faunal assemblages and habitat types in Broke Inlet, Western Australia." Thesis, Tweedley, James ORCID: 0000-0002-2749-1060 (2010) Relationships between faunal assemblages and habitat types in Broke Inlet, Western Australia. PhD thesis, Murdoch University, 2010. https://researchrepository.murdoch.edu.au/id/eprint/9363/.

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The work for this thesis was undertaken in Broke Inlet, a seasonally-open estuary on the south coast of Western Australia and the only estuary in that region which is regarded as “near-pristine” (Commonwealth of Australia, 2002). The only previous seasonal studies of the environmental and biotic characteristics of this estuary involved broad-based descriptions of the trends in salinity, temperature and ichthyofaunal characteristics at a limited number of sites. Furthermore, no attempt has been made to identify statistically the range of habitats present in the nearshore and offshore waters of this system, and the extents to which the characteristics of the fish and benthic invertebrate faunas are related to habitat type. These types of data provide not only reliable inventories of the habitat and faunal characteristics of Broke Inlet, but also a potential basis for predicting the likely impact of anthropogenic and climatic changes in Broke Inlet in the future. The main aims of this thesis were as follows. (1) To use the method of Valesini et al. (2010), which employs enduring environmental characteristics, to identify quantitatively the range of habitats present throughout the nearshore and offshore waters of Broke Inlet. The enduring environmental characteristics represent three broad categories, i.e. the location of any site in terms of its proximity to marine and freshwater sources, the degree of exposure to wave activity and the type of substrate and/or submerged vegetation. (2) To test the hypothesis that the species richness, density, diversity and species compositions of the fish and benthic macroinvertebrate faunas differ among habitat types, seasons and, in the case of the fish fauna, also years. (3) To test the hypothesis that the pattern of relative differences among habitat types, as exhibited by their faunal compositions, is correlated with that defined by their (i) enduring environmental characteristics and (ii) non-enduring environmental characteristics (water physico-chemical variables and sediment characteristics). A high resolution satellite image and a digital elevation model of Broke Inlet were used to measure the enduring environmental characteristics at 104 and 36 widely-distributed sites in nearshore and offshore waters, respectively. These data were used to construct separate Manhattan distance matrices for nearshore and offshore waters, which were then subjected to the CLUSTER and SIMPROF routines in PRIMER v6 to identify the various groups of sites that did not differ significantly in their environmental characteristics and which were thus considered to represent habitat types. Twelve and four distinct habitat types were identified in nearshore and offshore waters, respectively. The ichthyofaunas at sites representing 11 nearshore (A-K) and three offshore (A-C) habitat types were sampled seasonally for two consecutive years using seine and gill nets, respectively. A total of 83,047 fish was collected from nearshore waters, representing 27 species from 19 families, with 99.6% of those fish belonging to six species which represent the Atherinidae (Atherinosoma elongata, Leptatherina wallacei and Leptatherina presbyteroides) or Gobiidae (Afurcagobius suppositus, Pseudogobius olorum and Favonigobius lateralis) and complete their life cycles within the estuary. Each of these species were found at each nearshore habitat type, except for P. olorum, which was not caught at habitat A. The species richness, density and diversity of the nearshore fish fauna differed significantly among habitats, seasons and years, with habitat being the most influential factor. Generally, mean species richness and density were greatest at habitat types located in the entrance channel (B, G and H) and/or on the southern shore of the basin (C and G), while the fish assemblages were most depauperate at habitats near freshwater sources (A and J). The nearshore ichthyofaunal composition of Broke Inlet differed significantly among habitats, seasons and years, with the first again being the most influential. However, the extents of the overall differences in composition during each sampling occasion were moderate. The lack of very pronounced ichthyofaunal differences among the various habitat types reflects the widespread distributions and high abundances of the above atherinid and gobiid species, and particularly of A. elongata and L. wallacei, which typified the fish fauna of each habitat type on almost all sampling occasions. The most distinctive of the faunas were those at habitat types in the entrance channel, where L. presbyteroides and F. lateralis, which are typically found in higher salinities, were in their greatest densities, and where several marine straggler species, such as the labrids Notolabrus parilus and Achoerodus gouldii, were occasionally caught. Seasonal and inter-annual changes in ichthyofaunal composition were small and often not consistent across habitats. The pattern of relative differences among nearshore habitats in terms of their ichthyofaunal composition was correlated at a moderate level with that defined by their enduring environmental characteristics in all but one of the eight seasons. Such indicate that the ichthyofaunal composition likely to be found at any site in the nearshore waters of Broke Inlet at any time of year can be predicted, simply by assigning that site to its most appropriate habitat type on the basis of its enduring environmental characteristics. Differences in ichthyofaunal composition among habitat types were also correlated, but to a slightly greater extent, with those among the suite of non-enduring water physico-chemical variables, with salinity and the biomass of macrophytes being particularly relevant. Gill netting in the three offshore habitats yielded 1,050 fish representing 31 species. Species richness, catch rates and diversity all varied significantly among habitats, with the values for each of these biotic characteristics always being greatest at habitat A in the entrance channel and lowest at habitat B near the Shannon River mouth. These biotic variables did not always vary, however, among seasons and/or years. In contrast to the situation in nearshore waters, the offshore ichthyofauna comprised mainly marine estuarine-opportunists and marine stragglers, which contributed 84% to the number of species and 80% to the total number of fishes. The contribution of individuals belonging to the marine straggler guild was only 5% and no estuarine resident species were caught. Ichthyofaunal composition in offshore waters differed significantly among habitats, seasons and years, with habitat being the most influential factor. Faunal composition only differed among habitats in spring and autumn, and even then the extent of those differences was low. During those seasons, habitat B contained the most distinct and depauperate fauna, which was typified mainly by Mugil cephalus and Aldrichetta forsteri. In contrast, the fish assemblages at habitats A and C were also typified by Arripis georgianus, Arripis truttaceus, Rhabdosargus sarba, Pagrus auratus, Pseudocaranx dentex and Engraulis australis. The pattern of relative differences among offshore sites in terms of their ichthyofaunal composition was significantly correlated with that defined by their enduring environmental characteristics only in autumn, but was moderately correlated with that exhibited by the suite of non-enduring water physico-chemical variables in each season except summer. Seasonal sampling of benthic macroinvertebrates at six of the nearshore habitat types (A, C, D, F, H and K) for a year yielded 7,485 individuals representing 28 species and seven phyla and, at the three offshore habitat types (A-C), 2,459 individuals representing 26 species and eight phyla. Polychaetes (64 and 57%) and crustaceans (24 and 34%) were the most abundant taxa in nearshore and offshore waters, respectively. The mean density of invertebrates in the nearshore waters did not differ significantly among habitats, but did vary significantly among seasons, and was greatest in summer. The mean densities of invertebrates in offshore waters did not differ significantly, however, among habitats or seasons. The compositions of nearshore benthic macroinvertebrate assemblages differed significantly among habitats and, less conspicuously, seasons. Comparisons between the faunal compositions in each pair of habitats in spring and summer were almost invariably significantly different and to a moderate extent. However, such pairwise comparisons were rarely significant in autumn and winter. Habitats A and K contained the most distinct and depauperate invertebrate fauna, comprising mainly the polychaete Capitella capitata and amphipod Corophium minor, whereas the other habitats also contained large numbers of the polychaete Ceratonereis aequisetis. In offshore waters, the composition of the benthic macroinvertebrate assemblages differed to a low to moderate degree among habitats, with habitat B containing the most distinct fauna due to large densities of C. minor. The extent of seasonal differences in these faunal compositions was small. The pattern of relative differences among nearshore habitats in terms of their benthic macroinvertebrate composition was highly correlated with that defined by both their (i) enduring environmental characteristics and (ii) non-enduring water physico-chemical and sediment characteristics in spring and/or summer. Although the faunal and enduring environmental data were not correlated at offshore sites, the fauna and non-enduring environmental variables at those sites were correlated to a moderate extent. In summary, the composition of the nearshore fish fauna at any site in Broke Inlet at any time of year can now be predicted by allocating that site to a particular habitat type on the basis of its enduring environmental characteristics. The less consistent spatial correlations between the compositions of the offshore fish fauna and benthic macroinvertebrate faunas and the enduring environmental variables largely reflected the ubiquitous nature of the majority of the abundant species representing those faunas, i.e. they are typically at least moderately abundant in all habitats and thus have no strong preferences for a particular habitat type.

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Street, Martin John. "Analysis of Late Palaeolithic and Mesolithic faunal assemblages in the northern Rhineland, Germany." Thesis, University of Birmingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544001.

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The thesis presents an analysis of faunal assemblages from late glacial and early postglacial sites in the northern Rhineland, Germany, and examines changes in environmental conditions and material culture between 13,000 - 9,000 BP. After a summary of research history into the Palaeolithic and Mesolithic of the region, the geographical, stratigraphical and absolute chronological framework is examined, and the archaeological terminology is described in its northern European context. Methods used by the study are discussed. these include quantification, spatial patterning and detailed study of the evidence for butchering methods. The main part of the thesis is provided by the study of three faunal assemblages from the sites Andernach-Martinsberg (Central Rhineland) and Bedburg-Königshoven (Lower Rhineland). Two distinct faunal complexes from the former site date to the earlier and later parts of the late glacial interstadial ("Bolling" and "Alleröd"), the Bedburg fauna dates to the Preboreal. The eruption of the Laacher see volcano (11,000 BP) has conserved late glacial sites in the Central Rhineland below deep pumice layers, giving generally excellent preservation of faunal remains. At the site Andernach-Martinsberg, two distinct faunal complexes are associated with lithic assemblages of the Magdalenian (13,000 BP) and Federmessergruppen (12,000 BP) traditions. The criteria for distinguishing the two faunal elements are first discussed. The Magdalenian fauna is characterized by species typical of arctic-continental conditions; horse, reindeer and arctic fox are the commonest species. The Final Palaeolithic (Alleröd) fauna is composed of species associated with temperate, forested conditionsred deer, elk, aurochs. The discovery of the site Bedburg-Königshoven revealed the existence of a new category of valley-bottom site previously unknown in the region. Pollen analysis and radiocarbon dating assign the archaeological level to the Preboreal. The lithic assemblage is typical for the northern European early mesolithic tradition; the fauna is dominated by the aurochs, associated with other species characterizing temperate, forested conditions. The final part of the study looks at two small late glacial faunal assemblages from the Central Rhineland. The sites Miesenheim 2 and Miesenheim 4 illustrate how human and non-human activity can be studied in detail under the excellent conditions of preservation due to the Laacher see pumice, and illustrate the potential for investigation of human subsistence activity and environmental background away from the larger sites examined by the previous part of the study. For my parents, who never objected to my becoming an archaeologist

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Clarkin, P. E. "The ecology of macroalgal rafts and their associated faunal assemblages in the northeast Atlantic." Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.557305.

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SUMMARY This study describes some of the processes of macroalgal rafting important for the dispersal of benthic marine invertebrates and structuring intertidal species assemblages in Irish coastal : waters, using a combination of fieldwork and laboratory analyses. A novel method for assessing the density and distribution of seaweed rafts, which takes into consideration sea state was devised as a cost effective approach for surveying drifting algae in coastal and offshore marine environments. During the development of this surver .;, metaodotegy macroalgal rafts. were collected at various locations around the lrish coastlineand species assemblages were characterised. Species richness and abundance relationships were apparentiwhen factoring in.algal carrying capacity, and analysis indicated that rafts are most likely and opportunistic platform for species for survival and potential dispersal, rather than " assemblages where.species-specific responses to raft composition will occur. The abundance of drilling rafts in the offshore environment along with the presence of intertidal invertebrates highlights· the potential importance of such drifting habitats for the survival and movement of intertidal species across large expanses of ocean. The colonisation of Idotea species onto seaweed rafts was investigated to elucidate some of the initial smaller scale processes involved with rafting organisms and to understand some potential: behavioural associations. This was especially important, for species with direct development as they are considered to have low dispersal potential. Results indicate an activ~ colonisation of rafts by Idoteaindividuals from the surrounding water column as supposed to[ust a passive marooning along with algae detaching from the shore. Finally a comparative.analysis of shores that receive high and low levels of drift material from the ocean was undertaken to compare intertidal species assemblages, to expose anr biodiversity signatures of species colonising the shore from 1he arrival of macroalgal rafts. Abundance effects of species were clearly seen in this investigation, with some species displaying significantly higher abundances on high drift shores. These along with species richness effects indicate that.the arrival of rafts to a shore may have some effect .on . intertidal , species assemblages, although exposing any consequences of drift is difficult in such a dynamic and-complex marine environment.

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Lui, Tak-hang, and 呂德恒. "Macrobenthic faunal assemblages of a traditional tidal shrimp pond at Mai Po Marshes Nature Reserve, Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B29775346.

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Lui, Tak-hang. "Macrobenthic faunal assemblages of a traditional tidal shrimp pond at Mai Po Marshes Nature Reserve, Hong Kong /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20897455.

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Nicholson, Rebecca Anne. "An investigation into variability within archaeologically recovered assemblages of faunal remains the influence of pre-depositional taphonomic processes /." Thesis, Online version, 1991. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.292504.

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Rule, Beau Brenton. "Ediacaran biodiversity : palaeoecological assessment of successive latest Proterozoic (Neoproterozoic) faunal assemblages in the Western Flinders Ranges, South Australia /." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09SB/09sbr9352.pdf.

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Smith, G. M. "A contextual approach to the study of faunal assemblages from Lower and Middle Palaeolithic sites in the UK." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/646235/.

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This thesis represents a site-specific, holistic analysis of faunal assemblage formation at four key Palaeolithic sites (Boxgrove, Swanscombe, Hoxne and Lynford). Principally this research tests the a priori assumption that lithic tools and modified large to medium-sized fauna recovered from Pleistocene deposits represent a cultural accumulation and direct evidence of past hominin meat-procurement behaviour. Frequently, the association of lithics and modified fauna at a site has been used to support either active large-mammal hunting by hominins or a scavenging strategy. Hominin bone surface modification (cut marks, deliberate fracturing) highlight an input at the site but cannot be used in isolation from all other taphonomic modifiers as evidence for cultural accumulation. To understand the role of hominins in faunal assemblage accumulation all other taphonomic factors at a site must first be considered. A site-specific framework was established by using data on the depositional environment and palaeoecology. This provided a context for the primary zooarchaeological data (faunal material: all elements and bone surface modification) and helped explain the impact and importance of faunal accumulators and modifiers identified during analysis. This data was synthesized with information on predator and prey behavioural ecology to assess potential conflict and competition within the site palaeoenvironment. Results indicate that association of lithics and modified fauna are not sufficient evidence of a cultural accumulation; two sites (Swanscombe, Hoxne) demonstrate evidence of fluvial accumulation and disturbance. Whereas at Boxgrove, hominins had primary access to all fauna, fully exploiting carcasses. At Lynford, the mammoth remains were not modified by hominins, whilst other species only indicated exploitation for marrow, which conflicts with existing interpretations. I argue that hunting and scavenging are a continuum of behaviour, not necessarily represented at each site.

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WEBBER, ANDREW JULIAN. "METHODOLOGICAL ADVANCES IN THE USE OF FAUNAL GRADIENT ANALYSIS FOR REGIONAL PALEOECOLOGICAL INVESTIGATIONS IN THE TYPE CINCINNATIAN SERIES (UPPER ORDOVICIAN)." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1047068270.

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Alfaro, Lucas Joan Manel. "Influence of hydrothermal activity and substrata nature on faunal colonization processes in the deep sea." Thesis, Brest, 2019. http://www.theses.fr/2019BRES0089.

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Quatre décennies après leur découverte, nous savons maintenant que les sources hydrothermales sont répandues, diversifiées et dynamiques et qu’elles interagissent avec d’autres écosystèmes des grands fonds marins. Face aux potentiels impacts anthropiques qui pèsent sur les environnements hydrothermaux, il devient essentiel d’avoir une meilleure compréhension des processus qui façonnent la biodiversité de ces écosystèmes et de leurs interactions avec d’autres écosystèmes. Les processus structurant l'élaboration des communautés et contrôlant les interactions entre les habitats actifs, la périphérie et les communautés liées aux bois, ont été étudiés grâce à une vaste expérience de colonisation à 1700 m de profondeur sur le champ hydrothermal Lucky Strike (nord de la dorsale médio-Atlantique). Un cadre d’analyse moderne et multifacettes, basé sur la richesse spécifique, les traits fonctionnels et les isotopes stables, a été appliqué. Les résultats ont montré que les sites actifs supportent une richesse fonctionnelle plus élevée que les habitats périphériques.En outre, la diversité spécifique et fonctionnelle des habitats périphériques était très hétérogène, ce qui suggère qu’ils pourraient être particulièrement vulnérables aux impacts liés à l'exploitation minière. Les redondances fauniques et les liens énergétiques observés suggèrent que, plutôt que d'être des entités séparées, les habitats actifs et périphériques semblent être interconnectés. Les conditions environnementales et la présence de différentes ressources ont été identifiées comme étant les principaux facteurs influençant la biodiversité et la structure des communautés. Le rôle des bois en tant que potentielles « pierres de gué » pour la dispersion de la méio- et la macrofaune, non seulement pour les habitants des sources hydrothermales mais aussi pour ceux de la périphérie, est validé. Les résultats de cette thèse améliorent significativement notre compréhension des processus qui structurent les communautés associées aux sources hydrothermales et aux autres écosystèmes chimiosynthétiques dans les grands fonds marins et pourraient avoir des implications importantes dans l’élaboration de stratégies de protection dans le cadre d’éventuelles activités industrielles Four decades after their discovery, we know now that deep-sea hydrothermal vents are widespread, diverse and dynamic, and interact with other chemosynthetic-based and background ecosystems. In the face of potential imminent anthropogenic impacts, more than ever the understanding of the processes that shape vent biodiversity, in its multiple facets, and the interactions with other systems is of paramount importance. The early processes driving community assembly and interactions between hydrothermally active habitats, vent periphery and cognate communities, namely wood falls, were investigated with an extensive colonizing experiment at 1700 m depth onthe Lucky Strike vent field (northern Mid-Atlantic Ridge). A modern multifaceted framework of community assembly based on species richness, functional traits and stable isotopes was applied. Results showed that vent ecosystems support higher functional richness that background peripheral habitats.The latter were highly heterogeneous and unique in species and functions suggesting that they may be especially vulnerable to impacts, such as deep-sea mining. The observed faunal overlap and energy links suggest that rather than being separate entities, active and peripheral habitats may be considered as interconnected. Environmental conditions and the presence of different resources at vent, periphery and wood habitats, were identified as main drivers of biodiversity patterns and community structure. The roleof woods in the deep-sea as potential stepping stones for meio- and macrofauna, not only for “vent” but for periphery inhabitants, is validated. The results of this thesis significantly improve our understanding of vent and chemosynthetic communities and may haveimplications for their protection from industrial activities

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Cridland, Jennifer. "Late prehistoric Indian subsistence in northeastern Newfoundland : faunal analysis of Little Passage Complex assemblages from the Beaches and Inspector Island sites /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ34174.pdf.

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Trevarthen, Susan Michelle. "Who Went to Market?: An Urban and Rural, Late Eighteenth-Century Perspective Based on Faunal Assemblages from Curles Neck Plantation and the Everard Site." W&M ScholarWorks, 1993. https://scholarworks.wm.edu/etd/1539625800.

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Piculjan, Leda. "Morphometric and taphonomic analysis of the upper pleistocene faunal assemblage from Hijenska Pecina, Croatia." Master's thesis, Instituto Politécnico de Tomar. Universidade de Trás-os-Montes e Alto Douro, 2012. http://hdl.handle.net/10400.26/6021.

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Master Erasmus Mundus em Quaternário e Pré-História Hijenska pećina, an Upper Pleistocene cave site, is located in the Plovunija quarry, north of Buje in Istria, Croatia. A detailed taxonomic, metric and taphonomic analysis of the faunal assemblage is presented in this work. Material consists of about 453 bones, bone fragments and teeth. A big portion of the remains belong to cave hyena (Crocuta crocuta spelaea) and the thesis will try to answer the question if Hijena cave was a hyena den or a natural trap as suggested in earlier works.

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Pegg, Brian Peter. "The taphonomic history of the vertebrate faunal assemblage from British Camp, San Juan Islands, Washington." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51445.pdf.

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Cruaud, Perrine. "Influence des communautés microbiennes sédimentaires sur la répartition faunistique dans les sites hydrothermaux et les zones d'émissions de fluides froids du bassin de Guaymas." Thesis, Brest, 2014. http://www.theses.fr/2014BRES0059/document.

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Au niveau des fonds océaniques, souvent considérés comme des déserts aux conditions de vie extrêmes, des oasis luxuriants de vie existent pourtant. Les sources hydrothermales et les suintements froids, principalement localisés au niveau des dorsales océaniques et des marges continentales, vont permettre le développement de communautés microbiennes et animales très particulières. Le Bassin de Guaymas, situé dans le Golfe de Californie (Mexique) présente la particularité de regrouper à la fois une zone de sources hydrothermales et une zone de suintements froids, situées à une soixantaine de kilomètres l’une de l’autre, et toutes deux recouvertes par une épaisse couche sédimentaire. Ces deux zones sont également colonisées par des étendues de bivalves, des buissons de vers tubicoles ainsi que de tapis microbiens blancs ou colorés comparables. Afin de mieux comprendre le fonctionnement global de ces deux types d’écosystèmes et notamment le rôle structurant des communautés microbiennes sédimentaires sur la répartition des différents assemblages de surface, les travaux entrepris dans cette thèse se proposaient d’étudier les communautés microbiennes sédimentaires associés à la zone de suintements froids (Marge de Sonora) et la zone de sources hydrothermales (Southern Trough) du Bassin de Guaymas. Pour cela, la diversité des communautés microbiennes (Bacteria et Archaea) de différents habitats caractérisés par une faune et des profils géochimiques particuliers, a été étudiée grâce à l’utilisation d’une technique de séquençage haut-débit, le pyroséquençage par la technique du 454, combinée à d’autres techniques comme le FISH ou la PCR quantitative. Cette étude a permis de déterminer que la structure et la diversité des communautés microbiennes dans ces sédiments étaient très spécifiques de ces environnements. Par ailleurs, les colonisateurs présents en surface des sédiments reflétaient des profils géochimiques et des communautés microbiennes très différentes au sein des sédiments. Dans les sédiments colonisés par les tapis microbiens, riches en méthane, les communautés microbiennes dominantes (ANME, Deltaproteobacteria…) utiliseraient notamment les émissions de méthane des couches sédimentaires profondes et produiraient d'importantes concentrations de sulfures, nécessaires à l’installation des communautés microbiennes thiotrophes de surface formant les tapis. Ces fortes concentrations en sulfure excluraient en revanche les communautés animales de ce périmètre. A contrario, dans les sédiments présentant de faibles concentrations en méthane et en sulfure, permettant l'installation d’assemblages faunistiques variés, les communautés microbiennes méthanotrophes anaérobies et productrices de sulfure étaient minoritaires. L'activité et le métabolisme de ces colonisateurs de surface pourraient par ailleurs permettre le développement des lignées microbiennes détectées dans ces habitats (MBG-D, Chloroflexi…). L'analyse des larges jeux de données obtenus au cours de cette étude nous a donc permis de mettre en évidence un système dynamique complexe fonctionnant en équilibre entre les communautés microbiennes sédimentaires, les organismes colonisant la surface du sédiment et la composition géochimique des eaux interstitielles Whereas the deep-sea environment is often considered to be a desert, hydrothermal vents andcold seeps provide “oases” of biological activity on the ocean floor. Vent and seep ecosystems support complex food webs based on microbial chemoautotrophic primary production. These hydrothermal vent and cold seeps ecosystems both release hydrocarbon- and sulfide-rich fluids,fueling various surface assemblages such as mat-forming giant bacteria or symbiont-bearinginvertebrates (e.g. bivalves, tubeworms). In the Guaymas Basin, the nearby presence at a few tens of kilometers of cold seeps and hydrothermal vents coupled with comparable sedimentary settings and depths offer a unique opportunity to assess and compare the microbial community composition of these ecosystems. Tobetter understand their overall functioning, we studied sedimentary microbial communities associated with cold seep and hydrothermal vent areas in the Guaymas Basin. The diversity of microbial communities inhabiting sediments was studied using high throughput sequencing (454pyrosequencing), combined with complementary approaches, such as FISH and quantitative PCR. This study reveals that sediments found in the Guaymas Basin were colonized by microbial communities typically found in these types of ecosystems. Our results revealed a high similarity between microbial communities composition associated with the cold seep and hydrothermal vent areas as a probable consequence of the sedimentary context. Nonetheless, thermophilic and hyperthermophilic lineages (e.g.: Thermodesulfobacteria, Desulfurococcales, etc) were exclusively identified in hydrothermally influenced sediments highlighting the strong influence of temperature gradients and other hydrothermally-related factors on microbial community composition. Furthermore, sediments populated by different surface assemblages show distinct porewater geochemistry features and are associated with distinct microbial communities. Indeed, in the sediments underlying microbial mats characterized by high methane porewater concentrations,microbial communities were dominated by anaerobic methane oxidizers (ANME), known to produce sulfide which provides high fluxes of sulfide to the seafloor. In contrast, sediment associated microbial communities underlying faunal assemblages were characterized by a lower biomass and lower methane porewater concentrations in sediments, limiting porewater sulfide concentrations. Without elevated and toxic sulfide concentrations, faunal assemblages can colonize the surface. Together, geochemical and microbial surveys indicate that porewater methane concentrations play an important role in the microbial community structure and subsequently in the establishment of the surface colonizers. Furthermore, presence and activity of the surface colonizers influence the underlying microbial communities probably because of modification of energy source availabilities. Finally, the existence of similar microbial populations between the two ecosystems also raises the question of their dispersal mechanisms. Our results support the hypothesis of a potential continuity among deep-sea ecosystems. In absence of physical borders, environmental conditions (temperature, specific compounds associated withhydrothermal fluids) might select specific and highly adapted microorganisms from the pool of microorganisms dispersed globally across the seafloor

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Atzori, Clarissa. "Influence of port breakwaters on surrounding polychaete fauna." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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Harbours represent unique, complex and vulnerable environments from many points of view. Macrobenthic communities are important components of the harbour biota and polychaetes are the assemblage that best represents their state of well-being and can be used as indicators of environmental quality. The structure of the macrobenthic community and of the population of polychaete annelids that characterize the softbottom habitats of two ports of the Comunidad Valenciana (port of Sagunto, port of Calpe) was analysed and compared to verify the existence of a relationship between the variation in the species composition of the populations of polychaetes and the variation in the abiotic variables (granulometric classes of fine and medium sands, mud and the content of organic matter) in force in the two environments and at the two depths (2-3 m and 8-9 m). Sampling took place on 19 May in Sagunto and 20 May 2021 in Calpe and 24 replicates were obtained for each site: 12 for each depth interval (6 were necessary for the taxonomic study and 6 for the others analysis). The analysis of the polychaete fauna carried out in the sediment samples of the port of Sagunto made it possible to identify 303 individuals distributed in 76 taxa among 26 families, while those carried out for the port of Calpe allowed to identify 221 individuals distributed in 52 taxa between 17 families. The communities of the two ports differ in terms of abundance of individuals, species composition and presence / absence of Phyla Plantae, Sipuncula, Bryozoa, Chordata. All the abiotic variables above together with the depth had influenced the structure of the communities and polychaete assemblages, as demonstrated by the correlation existing between them. These last were characterized by low specific richness, diversity and a majority of species with low abundances that can be attributed to anthropogenic stress, especially pollution and / or other environmental stress factors, which act synergistically or not.

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Nakamura, Akihiro. "Development of Soil and Litter Arthropod Assemblages in Rainforest Restoration." Thesis, Griffith University, 2008. http://hdl.handle.net/10072/367553.

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Broadscale forest clearance is a major human-induced disturbance with devastating consequences for biodiversity. With a rise in public awareness of biodiversity, the last few decades have seen an increasing number of reforestation activities aimed at recreating natural habitat. To date, research on the outcomes of reforestation for biodiversity have mostly focused upon the recovery of vegetation structure and composition, with relatively little attention being paid to the recovery of fauna, especially invertebrates. Arthropods inhabiting soil and leaf litter constitute a considerable proportion of the biomass and diversity of a given faunal community, and exhibit strong associations with ecological functioning (i.e. soil formation, decomposition). The recovery of soil and litter arthropods in restored landscapes is therefore important, not only for the recovery of biodiversity but also for the re-development of a functioning ecosystem, a goal of most types of reforestation programs. However, we know little about the patterns of development of arthropod assemblages in reforested landscapes or the mechanisms underpinning any such patterns. The broad objective of this study was to investigate the effects of selected factors on the colonisation patterns of restored rainforest patches by soil and leaf litter arthropods. Criteria for selecting factors for study included their potential influence on the development of arthropod assemblages and their potential for manipulation by restoration practitioners. The study was conducted on the Blackall Range near Maleny, a mid-elevation (250-530 m a.s.l.) basaltic plateau in subtropical eastern Australia (26°S, 152°E). The plateau supported subtropical rainforest until European settlement in the 19th century, when most of the rainforest was cleared for pasture. The factors selected for study, in relation to the colonisation of restored habitat patches by soil and litter arthropods, were as follows: 1. the isolation of restored habitat patches from remnant forest; 2. the efficacy of inoculation (re-introduction of rainforest soil and litter arthropods) to restored habitat patches; 3. the quality and quantity of substrate (i.e. mulch) used during the initial stages of rainforest restoration; 4. the degree of shading and depth of substrate, and their interaction; and, 5. the short- and longer-term impacts of glyphosate herbicide on arthropod assemblages. To test explicitly the effects of these factors on arthropod colonisation of restored habitat patches, an experimental approach was adopted in this study. The first four factors were addressed by means of a manipulative field experiment. Small-scale habitat patches were created by adding sterilised mulch to an area previously treated with glyphosate herbicide, and covered with shadecloth, to simulate various conditions of forest restoration which may be experienced by colonising arthropods. In order to test for the impacts of a glyphosate herbicide on rainforest arthropods, I carried out a separate field experiment in which experimental patches were established within remnant rainforests. The experimental approach adopted in this study allowed for the construction of replicated units, while controlling for extraneous factors (e.g. heterogeneity of litter composition, habitat area, age of restoration), to enable robust examination of the effects of selected factors. To monitor assemblage composition, arthropods were collected using two methods: pitfall traps and extraction from litter. Responses of arthropods were analysed at two main levels of taxonomic resolution: ‘coarse’ arthropods (all arthropods sorted to Order/Class) and ants, identified to species. Before the field experiments, a survey was carried out to collect reference information on the distribution of soil and litter arthropods in remnant rainforests (undisturbed reference sites) and cleared pasture (disturbed reference sites) in the study region. Regardless of the sampling method (pitfall or litter extraction) or taxonomic resolution employed (coarse arthropods or ant species), the composition of arthropod assemblages clearly differed between rainforest and pasture. The information obtained from this survey generated potential bio-indicators of forested and cleared habitats, assisting interpretation of the data obtained from the field experiments. The effects of habitat isolation and inoculation were tested using ‘restored’ habitat patches which were established within cleared pasture at increasing distances (0, 15, 100 and ca. 400 m) from the edges of rainforest remnants. After nine months, rainforest-dependent taxa were found to have only colonised the habitat patches closely adjacent to rainforest remnants. Attempts to increase the extent of arthropod establishment by inoculation were unsuccessful: the majority of rainforest arthropods from the raw inoculum failed to persist within the isolated plots. The results indicated that many forest-dependent soil and litter arthropods may have a limited capacity to colonise isolated restoration sites, and/ or small experimental plots in the short term. Inference from the experiment was potentially limited by the relatively small temporal and spatial scales of restoration treatments. Avoiding these limitations in future research may require controlled and replicated efforts in experimental restoration over larger areas, based on collaborations between researchers and practitioners. To test the effects of quality and quantity of substrate on arthropod colonisation, habitat patches were established by adding either sterilised hay (a conventionally used mulching material in restoration projects) or woodchip mulch (a structurally more complex alternative), each at two depths (3-5 cm, 10-15 cm). Habitat patches were positioned within pasture adjacent to the edges of rainforest remnants to minimise the effect of isolation, and were all unshaded to create conditions similar to those during the initial stages of rainforest restoration. Despite its simple composition, hay performed better than woodchips in facilitating colonisation by arthropods characteristic of rainforest. However, neither hay nor woodchip mulch inhibited arthropods invading from the surrounding pasture. Shallow hay was favoured by ants characteristic of rainforest, but other groups of arthropods (e.g. Coleoptera, Isopoda) were associated with deep hay (10-15 cm). The optimum amount of hay may therefore vary among different groups of arthropods. The effects of shading and mulch depth, and potential interactions between them, were tested using habitat patches created with varying degrees of shading (none, 50% or 90% shading) and two depths of woodchip mulch (3-5 cm or 10-15 cm deep). The presence of shading, at both 50% and 90%, encouraged colonisation of habitat patches by arthropods characteristic of rainforest. However, only the more complete shading treatment (90%) inhibited re-invasion of restored patches by arthropods from the surrounding pasture habitat. Effects of mulch depth were significant only for rainforest-associated ant species which responded positively to shallow mulch within shaded plots. These results suggest that moderate levels of canopy closure, as produced by tree spacings typical of timber plantations, may be sufficient to facilitate colonisation of reforested land by rainforest arthropods. However, greater canopy shading (90%) is likely to be needed to inhibit re-invasion of arthropods from surrounding pasture habitat. Using deeper woodchip mulch does not necessarily create more suitable conditions for rainforest arthropods or offset the deleterious effects of the lower levels of shading. Paired herbicide-treated and control plots were created within rainforest remnants to test the short- (approximately three days) and long-term (approximately three months) impacts of herbicide application on soil and litter arthropod assemblages on the floor of the remnant rainforests. The results found no deleterious effects of glyphosate herbicide formulated as Roundup® Biactive™ on rainforest soil and litter arthropods; hence, this herbicide appears suitable for the control of unwanted plants in rainforest restoration projects, from the perspective of arthropod biodiversity. The outcomes of this study also have a number of important implications for the monitoring of the development of soil and litter arthropod assemblages in restored rainforests. First, pitfall traps (a commonly used sampling technique) can provide sufficient information on the state of arthropod assemblages in the context of subtropical rainforest restoration projects, although samples collected by this method alone do not necessarily represent the whole suite of soil and litter arthropods (e.g. cryptic arthropods that live in soil and litter). Second, a combination of higher-taxon sorting of all arthropods, together with species-level sorting of a significant major taxon (ants), provides a feasible compromise between comprehensiveness and detail in monitoring responses of arthropods. Third, ‘composite habitat indices’, such as those developed in this study to quantify the extent to which a site resembles rainforest or pasture in terms of its arthropod assemblage, can help alleviate problems associated with the patchy distribution of arthropod taxa in monitoring samples. The experimental approach adopted in this study provided information that would otherwise have been limited by post-hoc empirical studies alone. This study’s results demonstrated that the selected aspects of different restoration techniques and management affect the colonisation of soil and litter arthropod assemblages in rainforest restoration of old fields. Thesis (PhD Doctorate) Doctor of Philosophy (PhD) Griffith School of Environment Faculty of Science, Environment, Engineering and Technology Full Text

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Bito, Darren. "Structure and Dynamics of Herbivore Assemblages Along an Altitudinal Gradient: Indicators of Climate Change." Thesis, Griffith University, 2011. http://hdl.handle.net/10072/366400.

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Herbivory is one of the major ecosystem processes, as are pollination and seed dispersal, which drives ecological changes in both the phytophagous fauna and their host plant assemblages. The amount of herbivory damage on a host species represents not only the amount of herbivory pressure due to phytophagous insects but also the predatory pressure due to predators at higher trophic levels. Furthermore, additional interactions of climate and environmental factors determine the conditions of the host species and subsequently the assemblage of herbivorous insects that colonize them. All these direct and indirect, positive and negative influence of climate and environmental factors combined with the requirement to propagate themselves cascades to through the higher trophic levels down to assemblage of herbivorous insects and their host species at the lower trophic levels. This study considered the host specificity of caterpillars, herbivory pressure and herbivory damage on trees and shrubs along an altitudinal gradient within subtropical and temperate rainforest. The work has attempted to show how a selected ecological process (herbivory) is being influenced by various factors including altitude, ant predation pressure and host plant species, canopy strata and physical properties of leaves. Thesis (PhD Doctorate) Doctor of Philosophy (PhD) Griffith School of Environment Arts, Education and Law Science, Environment, Engineering and Technology Full Text

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Burel, Thomas. "Effet de l'hydrodynamisme sur la structure des communautés macroalgales et sur les interactions macroflore / macrofaune en zone intertidale." Thesis, Brest, 2020. http://www.theses.fr/2020BRES0019.

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Cette thèse vise à quantifier et à expliciter les effets de l’hydrodynamisme sur les biocénoses des estrans rocheux du Nord-Est Atlantique. Dans cette optique, plusieurs études ont été menées sur 14 sites de la pointe bretonne, à différentes échelles spatiales, de quelques mètres à une centaine de kilomètres. Pour étudier les variations de la structure des communautés de macroalgues et des assemblages à dominance macroalgale, deux méthodes d’échantillonnage biologique ont été utilisées pour la macroflore et la macrofaune. Un nouveau proxy de l’hydrodynamisme à petite échelle a été développé, la hauteur de vague in situ. La hauteur de vague in situ apparaît comme le facteur physique le plus important dans la structure interne des communautés macroalgales. En étudiant la différentiation de six communautés de macroalgues étagées sur l’estran, le rôle de l’hydrodynamisme semble mineur par rapport à l’élévation et à la durée moyenne d’émersion. Le passage des assemblages intertidaux d’une dominance macroflore à une dominance macrofaune est essentiellement expliqué par la hauteur de vague in situ. Les organismes sessiles répondent de façon différente à l’hydrodynamisme. De plus, l’existence de seuils de tolérance à l’hydrodynamisme a été mis en évidence. Au sein des assemblages dominés par les macroalgues, la hauteur de vague in situ module de façon significative les interactions faune-flore, fortes en haut et au milieu d’estran, et flore-flore, plus importantes en bas de la zone intertidale. L’étude de l’effet de l’hydrodynamisme sur une communauté macroalgale de milieu d’estran à l’aide de sept estimateurs (proxys) a révélé des réponses de la communauté différant selon l’estimateur. Les hauteurs de vague mesurées in situ et calculées selon le modèle SWAN semblent complémentaires pour évaluer le rôle de l’hydrodynamisme dans la structure des écosystèmes intertidaux rocheux à dominance macroalgale This thesis aims at quantifying and explaining the effects of hydrodynamics on the communities of the North-East Atlantic rocky shores. In that prospect, several studies were carried out in 14 sites at the western head of Brittany, at different spatial scales, from a few metres to a hundred kilometres. Two biological sampling methods were used for macroflora and macrofauna to study variations in the structure of macroalgal communities and seaweed dominated assemblages. A new proxy for small-scale hydrodynamics has been developed, in situ wave height.In situ wave height appears to be the most important physical factor in the internal structuring of macroalgal communities. By studying the differentiation of six macroalgal communities vertically distributed on the shore, the role of hydrodynamics seems to be minor compared to the elevation and the average duration of emersion.The shift in intertidal dominance from macroflora to macrofauna is mainly explained by in situ wave height. Sessile organisms respond differently to hydrodynamics. Interestingly, the existence of tolerance thresholds for hydrodynamics was highlighted. Within the communities dominated by macroalgae, the in situ wave height significantly modulates both the fauna-flora interactions, strong at the top and middle of the shore, and the flora-flora interactions, more important at the bottom of the intertidal zone.Studying the effect of hydrodynamics on a midintertidal macroalgal community using seven proxies revealed different community responses. The wave heights measured in situ and calculated using theSWAN model appear to be complementary in assessing the role of hydrodynamics in the structuring of macroalgal-dominated rocky intertidal ecosystems

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Moon, Mike. "Hydroacoustic Substrate Classification Accuracy and Faunal Assemblage Variation Between Artificial and Natural Rock Regions: Bear Lake, Utah/Idaho." DigitalCommons@USU, 2007. https://digitalcommons.usu.edu/etd/7682.

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Research designed to elucidate artificial reef efficacy in attraction and production is lacking. Delineation of the rock reef habitat, coupled with faunal patterns of substrate use within artificial and natural reef regions, will allow elucidation of the potential of artificial reefs to attract sport fishes, and function as surrogate natural habitat for the conservation of endemic fish species. We compared faunal assemblages and habitat complexity between artificial and natural reefs to access the efficacy of artificial reefs in conservation of the native community, and attraction of sport fishes. We used hydroacoustics to map artificial and natural rock reefs within Bear Lake. We compared the accuracy of Visual Bottom Typer (VBT, BioSonics, Seattle, WA) software to observed substrate in three regions of varying slope and rock complexity within Bear Lake. VBT demonstrated an ability to distinguish substrates regardless of rock complexity and slope, although inaccuracies were present. VBT biased classification towards predominant substrate in the survey regions. We compared benthic invertebrate and fish catch in natural and artificial reef regions to assess the utility of artificial reefs in fisheries management. We assessed the potential of artificial reefs to function as foraging habitat for endemic fishes within Bear Lake. We compared benthic invertebrate taxa abundances and diversity between one region of artificial reefs, and two natural reefs in spring and summer. The artificial reefs hosted prey consumed by endemic Bonneville whitefish and Bear Lake sculpin. We assessed the potential of artificial reefs to function in attraction of sport fishes, and conservation of endemic fishes. We compared differences in fish catch per unit effort (CPUE) and diversity on rock and soft substrate between one artificial and two natural reef regions. Sport fishes attraction to the artificial reefs was minimal. Winter cisco and whitefish used the artificial reefs similarly to natural reefs. Fall lake trout, crayfish, and yellow perch used artificial and natural reefs dissimilarly.

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Patterson, Molly O’Rourke. "FORAMINIFERA FAUNA RECOVERED FROM ANDRILL’S (ANtarctica geological DRILLing program) SOUTHERN MCMURDO SOUND (SMS) PROJECT." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/411.

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During the Austral Spring of 2007-2008 the ANtarctic geological DRILLing program (ANDRILL) recovered a 1,138 meter long sediment core AND-2A from the western side of the Victoria Land Basin for the Southern McMurdo Sound Project. The main goal of the project is to help establish a Neogene (~24 to 1.6 Mya) ice volume and climate record of Antarctica. This study focuses on the foraminifera record of AND-2A for paleoenvironmental and biostratigraphic purposes.AND-2A is unique in that it contains a Middle Miocene record (~17 to ~11 Mya) that includes the Middle Miocene transition of warm climatic conditions favoring polythermal ice sheets to major cooling into polar conditions resulting in the quasi-permanent formation of the East Antarctic Ice Sheet. This Middle Miocene transition has not been previously recovered from the Antarctic continental margin.The foraminifer record is not abundant; however, three assemblage zones are identified throughout AND-2A. Calcareous benthic taxa dominate every assemblage, as well as displaying similarities between modern shallow shelf assemblages around Antarctica and assemblages from previous drilling projects in the Ross Sea sector. The foraminifera record displays a dynamic environmental record and is supported by both the sedimentologic and other paleontologic findings.

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Thorpe, Teresa Mary. "The shark faunal assemblage of North Carolina, USA and assessment of a gillnet modification intended to reduce shark bycatch." Thesis, University of London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.536785.

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Kimball, Vaughn R. "Variability in late prehistoric prey-use strategies of the southeastern Columbia Plateau a test using the Harder Site faunal assemblage /." Online access for everyone, 2005. http://www.dissertations.wsu.edu/Thesis/Spring2005/v%5Fkimball%5F050505.pdf.

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Alves, Paula Rute Pereira Matono. "Fish assemblages as biological indicators of ecological quality in portuguese rivers." Doctoral thesis, Universidade de Évora, 2012. http://hdl.handle.net/10174/16172.

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No contexto da aplicação da Directiva-Quadro da Água, a ictiofauna é considerada como um relevante elemento biológico. Pela primeira vez foi desenvolvido um sistema de classificação para avaliação do estado ecológico dos ecossistemas aquáticos em Portugal, apesar dos constrangimentos impostos pela variedade e ubiquidade das pressões humanas e pelas peculiaridades dos agrupamentos piscícolas. Foram definidos grupos piscícolas para posterior estabelecimento de uma tipologia nacional de rios, foram seleccionadas métricas responsivas ás pressões humanas e foi desenvolvido um índice biótico piscícola. Os resultados evidenciam a necessidade de diferenciar correctamente a resposta da ictiofauna ás perturbações naturais e antropogénicas, considerando quer a variabilidade espacial, quer temporal dos agrupamentos piscícolas, típica dos cursos de tipo Mediterrânico. O uso de solo tem fortes consequências na degradação dos rios e na integridade da ictiofauna, sendo importante que a avaliação dos impactos considere a interacção entre diferentes pressões. A compreensão da influência relativa dos factores ambientais e humanos na ocorrência e abundância das espécies não nativas permitiu evidenciar o potencial papel das mesmas como indicadores biológicos. Esta tese contribuiu para o desenvolvimento e aperfeiçoamento de ferramentas de avaliação ecológica em Portugal, permitindo igualmente um aumento do conhecimento sobre a ecologia das comunidades piscícolas e funcionamento dos ecossistemas em rios de tipo Mediterrânico, com vista à sua conservação e reabilitação; ABSTRACT:Under the implementation of the Water Framework Directive fish fauna is considered a useful biological element. For the first time a Portuguese classification system to assess the ecological status of aquatic ecosystems was established, despite several constrains posed by the variety and ubiquity of human pressures and by the peculiarities of the fish assemblages. It was possible to define fish-based geographical groups for the subsequent establishment of a national river typology, to select metrics responsive to human pressures and to develop a fish biotic index. Results underline the needs for accurately differentiate between fish responses to natural and anthropogenic disturbances by accounting for the spatial and temporal variability of fish assemblages. Land use may lead to strong impacts on stream degradation and fish assemblages integrity and this evaluation must consider the interaction of different pressures. Understanding the influence of environmental and human factors in the occurrence and abundance of non-native species enlightened their role as a reliable tool in the ecological assessment of rivers. This thesis represents an important contribution to improve the ecological assessment tools in Portugal, while increasing knowledge on the ecology of fish communities and ecosystem functioning in Mediterranean climate rivers in view of their urgent conservation.

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Gardner, Neville P. "Small-scale distribution of two modern land snail faunas : islands and boundaries of relevance to the interpretation of subfossil assemblages." Thesis, Cardiff University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315293.

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Clague, Christopher Ian. "An investigation into the assemblage structure of the microchiropteran fauna of the Queensland tropical upland wet sclerophyll zone/." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18310.pdf.

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Manthi, Fredrick Kyalo. "The taphonomy of a micromammalian faunal assemblage from the Saldanha Bay Yacht Club : a contribution to the study of the South African west coast palaeoenvironments." Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/7710.

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Bibliography: leaves 129-146. This thesis provides a broad outline of the effect of taphonomic and ecological processes on the accumulation and transformation of micromammalian faunal assemblages, and the importance of the signatures left behind by these processes in the reconstruction of ancient ecosystems. Micromammalian remains recovered from a rich Terminal Pleistocene site near the Saldanha Bay Yacht Club (SBYC) along the South African west coast have been examined following Andrews' (1990a) procedures. In the investigation of the effect of taphonomy on the SBYC faunal remains, murids (rodents) and soricids (shrews) have been examined separately and in as much detail as possible. The analyses have shown that the long bones of the soricids exhibit a relatively higher degree of completeness than those of the murids, suggesting preferential preservation of the former. Additionally, soricid jaws have yielded higher minimum number of individuals (MNIs) than long bone counts whereas for murids the opposite is the case. These observations have indicated the need for more taxonomically resolved analyses on the effect of taphonomic processes on micromammalian remains. Three micromammalian species represented in the SBYC faunal samples (Tatera afra, Myosorex varius and Suncus varilla) yielded much higher MNI counts than did other species. This reflects the intermediate selective behaviour of the inferred accumulator of the fauna, the barn owl, although the spotted eagle owl has not been completely ruled out. The study of the SBYC micromammalian fauna has underscored the need to integrate both taphonomic and ecological factors in the attempts to infer potential predators that might have been responsible for the accumulation of microanalytic occurrences. This is also necessary for understanding the environmental contexts in which the fauna was accumulated and/or derived. The micromammalian species represented at SBYC have suggested that in the SBYC area some 15,000 years ago, there was a mosaic of microhabitats including well-vegetated and moist microhabitats, and an admixture of bush and sandveld. Overall, climatic conditions in the SBYC area when the microfauna accumulated were moderate, and generally not different from the conditions prevailing today.

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Kurchevski, Gregório [UNESP]. "As assembléias de peixes da represa de Jurumirim (alto rio Paranapanema, SP): status atual e mudanças históricas." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/99410.

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Made available in DSpace on 2014-06-11T19:30:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-29Bitstream added on 2014-06-13T20:39:51Z : No. of bitstreams: 1 kurchevski_g_me_botib.pdf: 972112 bytes, checksum: 5ba514fc94cea9053e0327b1bda69630 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Diversos fatores são responsáveis pela estruturação das assembléias de peixes em ecossistemas aquáticos artificiais. As relações entre o ambiente e os padrões de abundância e composição são provenientes das escalas temporais e espaciais avaliadas. Nesse sentido, as construções de reservatórios modificam o ambiente de tal forma que ocorre uma reorganização das assembleias de peixes. Com esse enfoque, o presente estudo objetivou caracterizar a distribuição espaço-temporal da fauna de peixes do reservatório de Jurumirim, avaliar o status de conservação e as interferências da represa nos atributos dessas assembleias. Três compartimentos do reservatório foram amostrados (lótico, transição e lêntico), além de duas lagoas na região de desembocadura do rio Paranapanema na represa. Foram registrados 52 táxons, sendo 14 deles considerados novos registros para a área de influência do reservatório. Desses novos registros, quatro espécies são de origem não nativa (alóctone): Triphorteus nematurus, Hyphessobrycon eques, Metynnis maculatus, e Cichla monoculus e uma exótica: Tilapia rendalli. As análises dos atributos ecológicos demonstraram, mesmo que incipiente, existe influência das condições impostas pelo barramento nas estruturas das assembléias. Dos atributos analisado, apenas o comprimento padrão médios e riqueza de espécies apresentaram diferenças estatísticas entre os trechos e os meses estudados. O padrão de distribuição longitudinal de riqueza específica parece ser atribuído às características peculiares desse sistema: baixa frequência de espécies introduzidas, presença de importantes tributários e condição trófica. O reservatório de Jurumirim apresenta filtros ecológicos que promovem certa resistência à invasões biológicas. Ainda, pela idade... Many factors are responsable for the structure of fish assemblages in artificial aquatic ecosystems. The relation between the environment and the patterns of abundance and composition come from temporal and spatial scales evaluated. Therefore, the constructions of reservoirs modify the environment leading to a reorganization of fish communities. The present study aimed to characterize the spatial-temporal distribution of fish fauna in Jurumirim Reservoir, determining the interferences of the dam in the fish community attributes, as well as evaluating the conservation status of fish assemblages in this artificial system. Three compartments of the reservoir were sampled (lotic, transition, lentic), as well as two lagoons in the mouth zone of Paranapanema River into the reservoir. 52 taxons were found, 14 of which considered new records. Of the new records, 4 species are alloctone species: Triphorteus nematurus, Hyphessobrycon eques, Metynnis maculatus and Cichla monoculus. The analysis of ecological attributes showed low influence of the conditions imposed by the dam in the fish assemblages. Only the average standard length and the species richness presented statistical differences between stretches and months. The pattern of longitudinal distribution of specific richness seems to happen due to the peculiar characteristics of that system: low frequency of introduced species, presence of the important tributaries and trophic condition. Jurumirim Reservoir presents ecological filters that promote some resistance to the progress of operational aspects of the invasions. Furthermore, because of reservoir’s age... (Complete abstract click electronic access below)

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Frizzera, Gabriela Linhares. "Limnologia, distribuição e composição da fauna de Oligochaeta (Annelida: Clitellata) e larvas de Chironomidae (Diptera) do Lago dos Manacás, município de Juiz de Fora, MG." Universidade Federal de Juiz de Fora, 2011. https://repositorio.ufjf.br/jspui/handle/ufjf/2156.

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Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-20T15:04:35Z No. of bitstreams: 1 gabrielalinharesfrizzera.pdf: 2367263 bytes, checksum: e04246423d57d883b86913ca2ec968e4 (MD5) Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-22T15:21:36Z (GMT) No. of bitstreams: 1 gabrielalinharesfrizzera.pdf: 2367263 bytes, checksum: e04246423d57d883b86913ca2ec968e4 (MD5) Made available in DSpace on 2016-07-22T15:21:36Z (GMT). No. of bitstreams: 1 gabrielalinharesfrizzera.pdf: 2367263 bytes, checksum: e04246423d57d883b86913ca2ec968e4 (MD5) Previous issue date: 2011-03-28 CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior O objetivo do presente estudo foi verificar a existência de variação espacial e temporal das variáveis abióticas e conhecer a estrutura da assembléia de Chironomidae e Oligochaeta do lago dos Manacás em meses que compõe o período seco e chuvoso e, a partir destas variáveis avaliar a qualidade da água deste ambiente. Foram realizadas três coletas, duas no período seco (agosto/09 e julho/10) e uma no chuvoso (fevereiro/10), em dois transectos, cada um com cinco pontos de coleta. As amostras de sedimento foram obtidas com draga do tipo Petersen em tréplicas, também foram obtidas amostras para a análise da granulometria e matéria orgânica. As amostras de água foram obtidas do fundo com uma garrafa de Van Dorn. Para analisar o estado trófico do ambiente foi calculado o índice de estado trófico (TSI) de Carlson e foi avaliada a presença e abundância de táxons indicadores de poluição. As variáveis limnológicas não apresentaram variações significativas entre os pontos de coleta e entre os transectos. Entretanto foram detectadas diferenças significativas entre as coletas realizadas, com exceção das variáveis oxigênio, carbono orgânico dissolvido e pH. A granulometria foi composta principalmente por sedimento fino e com alta porcentagem de matéria orgânica. A assembléia encontrada foi composta por 25 táxons e 1007 organismos. A maior riqueza e diversidade foi obtida na primeira coleta em agosto de 2009 e as menores densidade número de táxons foi encontrada no período chuvoso em fevereiro de 2010. Os quironomídeos foram os organismos mais abundantes em todo o período de coletas. Os pontos marginais (I e V) diferiram significativamente em relação à assembléia somente em um transecto na primeira coleta, nas demais, as margens foram consideradas iguais. Em agosto de 2009 pode ser observada uma grande quantidade de táxons adominantes. Neste período Caladomyia ortoni foi o principal táxon dominante. Em 2010 não foram observados táxons adominantes e Polypedilum foi dominante neste período. O índice calculado para determinar o estado trófico do lago dos Manacás classificou este ambiente como oligotrófico, mesotrófico e eutrófico ao longo do período de coletas. As variáveis abióticas diferiram temporalmente modificando as condições do ambiente e a estrutura da assembléia de Chironomidae e Oligochaeta. As concentrações de nutrientes aumentaram bastante demonstrando que o lago passa por um processo de alteração da qualidade da água. A baixa abundância de organismos encontrados no lago foi considerada comum, visto que também foi observado em outros locais. Apesar do índice de estado trófico mostrar que a qualidade da água do lago dos Manacás apresenta-se em más condições, a ausência e/ou a baixa densidade dos táxons considerados como indicadores de poluição não confirmam estes dados. The aim of this study was to verify the existence of the spatial and temporal variation of abiotic variables and know the structure of Chironomidae and Oligochaeta assembléia of the Manacás lake in months that compound the dry and rainy period and from this variable to evaluate the water quality of the environment. Three collects have been done, two in dry season (august/09 and july/10) and one in the wet season (february/10) in two transects each with five sampling points., Sediment samples has been collected by a bottom sampler Petersen. Three replicates have been made in each sample point for analysis of macroinvertebrates. Sediment samples were also obtained for analysis of particle size and organic matter. Water samples were obtained from the bottom with a bottle of Van Dorn. To analyse of the environment trofic status was calculated the trofic status index (TSI) of the Carlson and the presence and abundance of the pollution indicators taxa. Limnological parameters showed no significant variations among the sampling sites and among transects. However significant differences were detected between samples collected, with the exception of oxygen, dissolved organic carbon and pH. The particle size was mainly composed of fine sediment with a high percentage of organic matter. The assembléia found was composed of 25 taxa and 1007 organisms. The higher richness and diversity was obtained in the first collection in August 2009 and the lower density and number of taxa was found to the rainy season. Chironomids were the most abundant organisms during all period of collection. The marginal points (I and V) differed significantly with respect the assemblage only in transect A in the first collection in the others, the margins were considered equal. In August 2009 could be seen a large number of taxa adominantes. During this period the main dominant taxa was Caladomyia ortoni. In 2010 adominantes taxa were not observed, and Polypedilum were dominant in this period. The index to determine the trophic status of Manacás Lake rated this environment as oligotrophic, mesotrophic and eutrophic during the period of collection. The abiotic variables varied temporally changing environmental conditions and structure of the assembléia of Chironomidae and Oligochaeta. The concentrations of nutrients increased significantly showing that the lake goes through a process of change in water quality. The low abundance of the organisms found in the lake was considered common, already observed on others places. Although the trofic status index to show the water quality of Manacás lake is in bad conditions the absence and/or the low density of taxa considered how pollution indicators do not confirm this data.

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35

Stroppa, Gustavo Martins. "Composição da fauna de lagartos e anfisbenídeos (Squamata) em um fragmento de Mata Atlântica na Zona da Mata de Minas Gerais, Brasil." Universidade Federal de Juiz de Fora, 2012. https://repositorio.ufjf.br/jspui/handle/ufjf/1673.

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Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-06-01T14:33:12Z No. of bitstreams: 1 gustavomartinsstroppa.pdf: 1222382 bytes, checksum: 4ef99b2b99f409674d64468fbebf599f (MD5) Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-02T12:59:41Z (GMT) No. of bitstreams: 1 gustavomartinsstroppa.pdf: 1222382 bytes, checksum: 4ef99b2b99f409674d64468fbebf599f (MD5) Made available in DSpace on 2016-07-02T12:59:41Z (GMT). No. of bitstreams: 1 gustavomartinsstroppa.pdf: 1222382 bytes, checksum: 4ef99b2b99f409674d64468fbebf599f (MD5) Previous issue date: 2012-02-27 A ocupação das paisagens naturais por atividades humanas é uma das maiores ameaças à biodiversidade local. As consequências desta ocupação são a remoção dos habitats naturais e a formação de fragmentos isolados e menores que aquele original. Estudos sobre a composição e padrões de distribuição da fauna de lagartos e anfisbenídeos em ambientes de Mata Atlântica no estado de Minas Gerais são escassos. O presente trabalho teve como objetivo realizar um inventário faunístico de lagartos e anfisbenídeos na Fazenda Fortaleza de Sant’Anna, na Zona da Mata mineira, e fornecer informações a fim de ampliar o conhecimento da distribuição e composição da fauna de répteis Squamata do estado de Minas Gerais. A região onde o estudo foi realizado está inserida em uma das áreas prioritárias para a conservação da herpetofauna do Estado. As amostragens foram feitas no período entre fevereiro e dezembro de 2011, totalizando 28475 dias/balde e 56950 dias/funil. Foram instalados conjuntos de armadilhas de interceptação e queda, e armadilhas de funil em nove pontos do fragmento, três localizados na matriz no entorno da mata, três na borda da mata e três em áreas centrais do fragmento. Foram registrados 47 espécimes pertencentes a 12 espécies, distribuídas em 10 famílias: Amphisbaenidae, Anguidae, Diploglossidae, Gekkonidae, Gymnophthalmidae, Leiosauridae, Phyllodactylidae, Scincidae, Teiidae e Tropiduridae, sendo que o filodactilídeo Gymnodactylus darwinii foi a espécie mais abundante (n = 15) e a única encontrada em todas as áreas de amostragem com armadilhas. A espécie que se destacou dentre as menos abundantes foi Diploglossus fasciatus (n = 1), pois seus hábitos solitários e a baixa densidade em suas populações tornam seu registro mais raro. Entre as 12 espécies registradas, as exclusivas do ambiente “Matriz” foram Amphisbaena microcephala, Diploglossus fasciatus e Ophiodes striatus, no de “borda” foram Mabuya dorsivittata e Placosoma glabellum e na “Central” foi Heterodactylus imbricatus. Não houve diferença significativa na frequência de ocorrência entre as áreas de matriz, borda e centro do fragmento (t = 0,1955; p= 0,8989). A análise de variância mostrou que não houve diferença significativa no número de espécimes amostrados por cada área (t = 0,5937; p = 0,6717). A curva de acumulação de espécies dos pontos de coleta indicou que não houve estabilização no acréscimo de espécies de lagartos e anfisbenídeos para a região, indicando a necessidade de continuidade do trabalho. The occupation of the natural landscape by human activities is the major threat to local biodiversity. Its consequences are the removal of natural habitats and formation of isolated fragments smaller than the original ones. Studies on composition and distribution patterns of the lizards and amphisbaenians in environments of the Atlantic Forest in Minas Gerais state are scarce. This study conducted an inventory of lizards and amphisbaenians fauna at Fortaleza de Sant'Anna farm in Zona da Mata of Minas Gerais, and provided information to expand knowledge of the distribution and composition of Squamata reptile fauna of the state of Minas general. The region of study is one of the priority areas for conservation of the herpetofauna in the state. The samples were taken in the period between February and December 2011, totaling 28475 days / bucket and 56950 days / funnel. Were installed sets of pitfall traps, funnel and drop in nine points of the fragment, three located in the matrix surrounding the forest, three in the forest edge and three in central areas of the fragment. We recorded 47 specimens belonging to 12 species were registered, distributed in 10 families: Amphisbaenidae, Anguidae, Diploglossidae, Gekkonidae, Gymnophthalmidae, Leiosauridae, Phyllodactylidae, Scincidae, Teiidae and Tropiduridae, and the filodactilídeo Gymnodactylus darwinii was the most abundant species (n = 15) and the only found in all of the sampling areas with traps. The species that stood out among the least abundant ones was Diploglossus fasciatus (n = 1), because their lonely habits and the low density in their populations turn his/her rarer registration. Among the 12 registered species, the exclusive of the "Matriz" atmosphere were Amphisbaena microcephala, Diploglossus fasciatus and Ophiodes striatus, in the one of "border" they were Mabuya dorsivittata and Placosoma glabellum and in the "Centro" it was Heterodactylus imbricatus. There was not significant difference in the occurrence frequency among the head office areas, it embroiders and center of the fragment (t = 0,1955; p = 08989). The variance analysis showed that there was not significant difference in the number of specimens for each area (t = 0,5937; p = 06717). The curve of accumulation of species of the collection points indicated that there was not stabilization in the increment of species of lizards and anfisbenídeos for the area, indicating the need of continuity of the work.

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36

Johnson, Zane B. "Submerged wood inhabiting macoinvertebrates of the Elm Fork of the Trinity River, Texas: Assemblage analyses, comparisons to the benthic fauna, and a study of Cyrnellus fraternus (Trichoptera: Polycentropodidae)." Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc2843/.

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Taxonomic composition and spatio-temporal variability of macroinvertebrates inhabiting snags were examined from an 8-km segment of the Elm Fork of the Trinity River. Seventy-seven macroinvertebrate taxa were collected from submerged wood during the study. Assemblages were highly variable spatially and temporally, especially among seasons. An ordination of species and environment did not find snag taxa to have striking correlations with many of the selected environmental variables, although there were some trends in flow-mediated species distributions. There were significant seasonal differences in the abundances of some taxa, particularly among the Chironomidae (Diptera). The Tribe Orthocladiini was numerically abundant during the winter, while the Tribes Chironomini and Tanytarsini dominated the summer and autumn. Additionally, this study included a secondary production and microdistribution analysis of a population of the caddisfly Cyrnellus fraternus. Distributions of C. fraternus were restricted to snags, the most stable substratum for retreat building and for resisting periodic high waters. Larvae were not found in the soft sand and mud benthic habitats near submerged wood. The insects were multivoltine with a minimum of three generations per year. Pupae were collected July through September and adults emerged from May through October. The population overwintered as larvae. Estimated annual production was 1,015.4 mg/m2/yr. Mean standing stock biomass was 61.24 mg/m2, the cohort production/biomass ratio was 4.59, and the annual production/biomass rate was 16.58/yr for this population. Standing stock biomass ranged from 1.6 to 349.1 mg/m2 during the year and was significantly higher in autumn and summer than winter. Larvae were more abundant in the lower portions of the study area where flow was reduced for much of the year, than in the upper reaches, characterized by higher current velocities. C. fraternus larvae were found in their highest numbers on snags with dense deposits of silt and sand.

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Abgrall, Corentin. "Réponse de la flore, de la faune du sol et de leur substrat à l'introduction d'espèces exotiques envahissantes végétales." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR056/document.

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Les espèces exotiques envahissantes végétales sont des plantes introduites et naturalisées hors de leur aire de répartition native et capables de maintenir et d’accroitre leur population. Certaines sont considérées comme transformatrices de par leur effet sur les écosystèmes : leur structure, leur fonctionnement ainsi que leur communauté végétale et animale. Ces transformations peuvent rendre certaines de ces espèces nuisibles de par leurs impacts écologiques et économiques important. Les travaux réalisés dans le cadre de cette thèse et présentés ici ont pour objectif d’approfondir les connaissances sur l’impact des invasions biologiques. La faune du sol, la végétation native et leur substrat ainsi que son fonctionnement ont été étudiés à différentes échelles spatiales. Deux espèces exotiques, envahissantes en Europe, ont été considérées comme modèles pour ces travaux : le robinier faux-acacia (Robinia pseudoacacia) et la renouée du japon (Reynoutria japonica). Premièrement, une méta-analyse globale a permis de démontrer l’effet positif des invasions biologiques végétales sur l’abondance de certains groupes de la faune du sol, notamment les consommateurs primaires, en fonction de la structure de l’habitat (ouvert ou fermé). Ensuite, une étude à large échelle sur le robinier faux-acacia a permis d’illustrer les différences qui peuvent exister dans la réponse des écosystèmes forestiers aux invasions le long d’un gradient latitudinal. Ce gradient, composé de quatre régions distinctes en Europe de l’Ouest présente des différences de climat et de végétation dominante, ces différences modifiant l’impact du robinier faux-acacia. Une étude approfondie sur le robinier faux-acacia en Normandie a permis de mieux comprendre l’effet du robinier faux-acacia sur les communautés animales et végétales ainsi que sur le fonctionnement des écosystèmes par comparaison avec deux essences natives dominantes. Finalement, une manipulation expérimentale en laboratoire a démontré l’impact des composés allélopathiques de la renouée du Japon sur une partie de la faune du sol. Cette étude a montré que certaines espèces exotiques envahissantes sont susceptibles d’influencer la faune, et les réseaux trophiques, du sol par leur métabolisme secondaire. Ces travaux illustrent l’intérêt, dans le contexte des invasions biologiques végétales, de l’étude simultanée des compartiments aériens et souterrains à différentes échelles spatiales Invasive alien plants are species introduced and naturalized outside of their native distribution range and which have the capacity to maintain and expand their population. Some of these species are considered to be ecosystem transformers by altering their structure, functioning as well as resident animal and plant communities. These induced alterations make some of these species undesirable through their ecological and economical impacts. The work presented in this thesis aimed at a better understanding of the impact of biological invasions by alien plants. The soil fauna, native vegetation and their substrate, as well as ecosystem functioning, were studied at different spatial scales. Two exotic alien species, invasive in Europe, were considered as biological models for this work: the black locust (Robinia pseudoacacia) and the Japanese knotweed (Reynoutria japonica). Firstly, a global meta-analysis demonstrated the positive impact that plant invasions can exert on the abundance of some groups within the soil fauna, notably primary consumers, within different types of habitats (open or closed). Then, a large-scale study on the black locust revealed the differences that can can occur in the response of forest ecosystems to invasions along a latitudinal gradient. Study sites along this gradient, distributed amog four distinct regions in western Europe, exhibit differences in climate and dominant native vegetation which can alter the impact of the black locust. A detailed study on black locust impact in Normandy demonstrated the impact of R. pseudoacacia on native plant and soil fauna communities, as well as some ecosystem functions, in comparison to two native tree species. Finally, a laboraty experiment demonstrated the impact that allelopathic compounds extracted from Japanese knotweed rhizomes can have on some organisms within the soil fauna. This study showed that some invasive alient plants can influence the soil fauna, and soil food webs, through their secondary metabolism. This thesis illustrates that simultaneous study of both aboveground and belowground ecosystem compartments at different spatial scales is of interest in the context of biological invasions

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(9810980), Richard Knight. "Structure of faunal assemblages on rehabilitated land." Thesis, 2002. https://figshare.com/articles/thesis/Structure_of_faunal_assemblages_on_rehabilitated_land/13424549.

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"The present study had three objectives : firstly to examine the success of rehabilitation efforts on post mining substrates by analysis of trappable small vertebrates recolonising rehabilitated areas compared to control unmined areas ; secondly to examine the relationship between small vertebrates and the availability of appropriate microclimates in the environment by assessing a series of vegetation and habitat variables ; and thirdly to provide a comprehensive non-avian vertebrate species for the Blair Athol Coal Mine Lease." -- abstract. The present study had three objectives: firstly to examine the success of rehabilitation efforts on post mining substrates by analysis oftrappable small vertebrates recolonising rehabilitated areas compared to control unmined areas; secondly to examine the relationship between small vertebrates and theavailability of appropriate microclimates in the environment by assessing a series of vegetation and habitat variables; and thirdly to provide a comprehensive non-avian vertebrate species list for the Blair Athol Coal Mine Lease. A total of76 native species were identified on the mining lease, including 17 species of frogs, 27 species oflizards, 11 species of snakes, 2 species ofturtles and 19 mammals. as well as 8 introduced species. This study recorded six vertebrate species not previously known from the Clermont region: Cyclorana platycephala, Limnodynastes convexiusculus, L. sa/mini. {Jperolia mimula. Varanus acanthurus, and lsoodon macrourus. Surveys were performed at 21 sites over four sampling periods, including 12 reference sites, and nine rehabilitation sites. Rehabilitation sites of various ages were comparable in terms of vegetation and abiotic factors, and were significantly different from control sites, however the 1984 rehabilitation area had species diversity, relative abundance of species and guild structure similar to control sites. A remnant patch ofvegetation was similar to control sites in terms of vegetation and abiotic factors, but had lower species diversity and different relative abundances of species; suggesting that assessment of an ecosystem on the basis ofstructural components of the vegetation and abiotic environment alone may not adequately reflect the presence ofa functional ecosystem because ofthe confounding problem ofecosystem fragmentation. As a consequence. studies based on vegetation or physical attributes may not be sufficient to judge the success ofrehabilitation with respect to vertebrate fauna. The results produced by analysis ofabundance and diversity of insectivorous reptiles was found to reflect the pattern produced by analysis of all data, and as such this group is considered an appropriate indicator of ecosystem health in this community.

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Giguere, Thomas. "Characterization of hydrothermal vent faunal assemblages in the Mariana Back-Arc Spreading Centre." Thesis, 2020. http://hdl.handle.net/1828/11712.

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Researchers have learned much about the biological assemblages that form around hydrothermal vents. However, identities of species in these assemblages and their basic ecological features are often lacking. In 2015, the first leg of the Hydrothermal Hunt expedition identified likely new vent sites in the Mariana Back-arc Spreading Center (BASC). In 2016, the second leg of the expedition used a remotely operated vehicle (ROV) to confirm and sample two new sites and two previously known sites. My first objective is to identify the animals collected from these four vent sites. In these samples, I identify 42 animal taxa, including the discovery of four new vent-associated species, five potentially new species and six taxa not previously reported in the Mariana BASC vents. My second objective is to combine these new data with previous studies and examine the species distributions among all known vent sites in the Mariana BASC using the α-, β-, and γ-diversity framework. I present updated species absence-presence lists for all eight Mariana BASC vent sites, which begin to resolve some of the issues with species identification. In this thesis, my approach to assessing β-diversity is novel in the field of hydrothermal vent ecology. My work also provides the first intra-regional scale assessments of β-diversity that include all sites known in a vent system. My third objective is to explore environmental factors driving these species distribution patterns. The α-diversity of BASC vent sites gradually increases with latitude, and the β-diversity calculated using the Raup-Crick index correlates with distance to nearby vent sites. Stochastic assembly processes likely shape the diversity patterns throughout the Mariana BASC as few environmental variables are known to correlate with these patterns. My fourth objective is to compare the β-diversity patterns between the Mariana BASC vent sites and those in two other vent systems: the Mariana Arc and the Juan de Fuca Ridge. The γ- and average α-diversity values for the BASC vents are relatively low compared to the other two systems. The Jaccard index revealed that the average number of shared species among the Arc vent sites is much lower than those of the BASC and the Juan de Fuca Ridge. The Raup-Crick index indicates that stochastic processes explain the average β-diversity of the Mariana BASC vents better than those of the Mariana Arc and Juan de Fuca Ridge. Graduate 2021-04-17

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Steffen, Martina Lianne. "Early Holocene hearth features and burnt faunal assemblages at the Richardson Island Archaeological Site, Haida Gwaii, British Columbia." Thesis, 2006. http://hdl.handle.net/1828/1891.

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Hearth features are often central to hunter-gatherer campsite organization and activities and have long been a focus of study for archaeologists. Among these studies, few have undertaken analysis of calcined faunal remains contained within these features. This thesis investigates human subsistence and occupation at the Richardson Island site, Haida Gwaii, B.C., through examination of the hearth-derived fauna. This is one of very few faunal assemblages from the early Holocene on the northern Northwest Coast and dates to between 9300 and 9100 BP. Description of the taxa in the assemblages is followed by discussion of human technological adaptations for procurement. Hearth replications and a controlled burning experiment demonstrate the complex taphonomic trajectory of burnt fish bone assemblages. Cluster analysis showed weak hearth groupings based largely on taxonomic richness. Chi-squared tests showed that some Kinggi Complex artifact types vary in frequency when in close proximity to hearths. Overall, hearths and surrounding deposits show maritime capacities in the early Holocene.

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Willerton, Ila Moana. "Subsistence at Si•čǝ’nǝł: the Willows Beach site and the culture history of southeastern Vancouver Island." Thesis, 2009. http://hdl.handle.net/1828/1723.

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Culture types in Pacific Northwest archaeology are characteristic artifact assemblages distinguishing different prehistoric periods. Assemblages indicate a culture type transition during the 2,630 BP–270 BP occupation of Willows Beach (DcRt-10), southeastern Vancouver Island. Faunal remains could reveal links to subsistence patterns, following Croes’s theory that culture type change reflects subsistence intensification. Five dated DcRt-10 faunal assemblages underwent taxonomic and size classification, weighing and MNI calculation. Vertebrate weight and NISP percentages were compared between stratigraphic units associated with the later Gulf of Georgia and earlier Locarno Beach culture types. The youngest assemblage contains a smaller proportion of land mammal bone, suggesting increased sea mammal, fish, and bird procurement. Faunal remains also suggest a greater variety of taxa exploited over time. Faunal assemblages suggest that culture type change at DcRt-10 is the product of subsistence change, increasing knowledge of the culture historic sequence of this region.

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Bountalis, Alexandra Clare. "Cave usage and the implications of multiple taphonomic agents on a faunal assemblage." Thesis, 2013. http://hdl.handle.net/10539/12363.

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The means in which fossil accumulations in the caves of southern Africa have formed is of great importance. One method of accumulation is via the collecting behaviours of a variety of mammalian species. The core of said behaviour is in the use of caves by these species. This project was designed to give insight to the way that animals in the Cradle of Humankind, South Africa are using caves today. The objective of this research is to give a new understanding to the amount that caves are used by various taxa in South African cave systems, with particular regard to taphonomic agents and potential taphonomic agents. This study was accomplished over a 20-month period by setting up motion sensor cameras outside of cave entrances at the Malapa Nature Reserve. Results have shown that animals use caves at high frequencies, crucial to recognize when examining fossil accumulations.

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Thompson, Andrea. "A zooarchaeological analysis of a late Dorset faunal assemblage from the KcFs-2 site (Nunavik, Quebec)." Thèse, 2011. http://hdl.handle.net/1866/5144.

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Ce mémoire consiste en une analyse zooarchéologique d’un assemblage faunique provenant d’un site Dorsétien des Îles Nuvuk dans l’Arctique canadien. Les données fauniques ont été analysées statistiquement en appliquant des indices d’utilité économique et des indices de densité des os. Une étude concernant le niveau de conservation de l’assemblage a révélé peu d’évidence de modification taphonomique des spécimens. Les analyses fauniques ont permis d’identifier une stratégie de subsistance de type généraliste et basée sur l’exploitation de mammifères marins, surtout des phoques annelés, pratiquée par les occupants du site de KcFs-2. Une prédominance d’individus immatures (phoques annelés) dans l’assemblage indique une abondance de ressources marines dans les régions du nord de la Baie d’Hudson et du détroit d’Hudson au moment de l’occupation, ce qui est aussi manifeste dans des études antérieures concernant les économies des peuples du Paléoesquimau tardif pour la période donnée. L’occupation du site de KcFs-2 s’est produite durant la période du Dorsétien récent au Nunavik (1500-800 B.P.), et la séquence est définie comme ayant été multi-saisonnière (de l’hiver à l’été). L’analyse des produits de l’industrie osseuse (têtes de harpons et sculptures en ivoire) a permis de confirmer l’affiliation culturelle des occupants. This thesis presents a zooarchaeological analysis of a faunal assemblage from a Dorset site (KcFs-2) on the Nuvuk Islands in the Canadian Arctic. The faunal data was analyzed through the application of bone density and economic utility indices and bivariate statistical tests. A brief taphonomic study was also undertaken, showing that the assemblage was not heavily affected taphonomically. The faunal analysis revealed a generalized subsistence strategy with an intensified focus on marine mammal exploitation, specifically ringed seals. The predominance of immature ringed seals exposed through the study indicates an abundance of marine resources in the northern Hudson Bay and Hudson Strait regions during the period under study, which correlates well with existing studies concerning Late Palaeoeskimo economy. Occupation of the KcFs-2 site occurred in the Late Dorset period of Nunavik (1500-800 B.P.) and is defined on a multi-seasonal level, from late winter through summer. Analyses of the organic artefact assemblage (harpoon heads and sculpted objects) served to confirm the relative dating of the site and aided in the definition of the cultural affiliation of the inhabitants of the KcFs-2 site.

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YEN, WAN-TING, and 言婉婷. "Marine Paleo-Primary Production Variability Estimated by Planktic Foraminifer Fauna Assemblages in the Tropical Pacific." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/89614486567159914841.

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碩士 國立臺灣海洋大學 應用地球科學研究所 99 Marine primary production variability plays an essential role in modulating global carbon cycle that is a key component in regional/global climate changes. Estimating late Quaternary primary production by the uses of faunal-based transfer functions with modern satellite primary production data derived from chlorophyll a concentration has been successfully applied for the northern Indian Ocean and equatorial Pacific. However, few studies have been conducted for the western Pacific warm pool. Here we attempt to establish a paleo-productivity transfer function for estimating paleo-primary production in the tropical Indian and Pacific. We have compiled western Pacific and Indian coretop fauna data from the MARGO project (Multiproxy Approach for the Reconstruction of the Glacial Ocean Surface) and calibrated the fauna data by SeaWiFS data of chlorophyll a concentrations (1998-2007) for each coretop. In order to understand the sensitivities and accuracies of different methods for primary production estimates, we applied Imbrie-Kipp transfer function (IKTF) and Modern Analogus Technique (MAT) with different species abundance data of planktic foraminifer assemblages, or with different geographic subsets of coretop data. Our results indicate that the transfer function using 28 species abundance data is obviously better than that of 11 species. However, using different inputs of geographic subsets of coretops shows minor, insignificant differences in the performance of transfer function estimates. Therefore we consider the geographic distribution of coretops is not important and the whole western Pacific and Indian coretop data for calibration would be an optimum choice. We applied this transfer function applied to a western Pacific warm pool core MD052928, and found primary productivity changes on glacial to interglacial time scales are controlled regional current and upwelling, which are in response to changes in sea-levels.

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張詠斌. "Late Quaternary High-Resolution Planktonic Foraminifer Stable Isotope and Faunal Assemblage Record of the Southern Benguela Current." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/20180528822389787630.

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Moura, Viviane Andrade Fernandes dos Santos. "Taphonomic approach to the faunal assemblage of the Lower Paleolithic site of Visogliano (MIS 13 and 10), trieste, Italy." Master's thesis, 2021. http://hdl.handle.net/10400.26/39300.

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Taphonomy is a tool widely used by zooarchaeologists to understand the strategies of prehistoric human subsistence. In assemblages where the preservation of the bone surface is poor, it is necessary to apply different types of methods and analysis to better understand and interpret data. The archaeological site of Visogliano has one of these assemblages. The site is a Middle Pleistocene shelter located in Trieste Karst, north-eastern Italy, that can be dated to the 350–500 kyr time span. Human remains, lithic industry and an extensive faunal assemblage have been excavated in the past. This is the first taphonomic approach carried out on faunal remains from this archaeological site. From an exploratory work, a selection of three layers was studied and analysis were carried out. Our results demonstrate that the bone surface is greatly altered, mostly due to concretions and the action of water. And finally, corroborates positively in the hypothesis of an involvement between hominins and faunal remains, through possible butchery marks

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Alghaled, Huda. "An Upper Ordovician faunal assemblage from the Neuville Formation of Québec, including an exceptionally preserved soft bodied sea anemone, Paleocerianthus neuvillii n. sp." Thèse, 2019. http://hdl.handle.net/1866/22740.

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Peck, Helene. "The application of ecological models and trophic analyses to archaeological marine fauna assemblages: towards improved understanding of prehistoric marine fisheries and ecosystems in tropical Australia." Thesis, 2016. https://researchonline.jcu.edu.au/48929/1/48929-peck-2016-thesis.pdf.

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This project focuses on the high-resolution analysis of archaeological marine fauna assemblages, using methodologies situated in an evolutionary ecology theoretical framework. These assemblages come from eight Kaiadilt archaeological sites across the South Wellesley Archipelago, which are a valuable dataset to examine not just dietary composition of foragers in the islands but also long-term patterns in the temporal and spatial availability of subsistence resources. This study also represents the first Australian investigation that applies trophic level analysis to archaeological marine fauna assemblages in order to explore anthropogenic effects on prehistoric fisheries (e.g. Bourque et al. 2008; Reitz et al. 2009; Quitmyer and Reitz 2006). Located in the southern Gulf of Carpentaria, in the central north of Australia the study area for this project focuses on Bentinck, Sweers and Fowler Islands, three of the largest islands in the South Wellesley Archipelago and the traditional home of Kaiadilt people. A three phase cultural chronology spanning the past c. 3,500 years is suggested for the study area, based on a comprehensive suite of 128 radiocarbon dates collected from cultural deposits, combined with results from linguistic studies (see Memmott et al. 2016). This archaeological research undertaken in collaboration with the Kaiadilt Aboriginal community has resulted in the recording of cultural places on their lands. Community engagement has been an integral part of this research and ultimately has contributed to the success of the project. At a regional level this thesis contributes to the discourse about Aboriginal subsistence practices in northern Australia for the late Holocene. The project provides a large dataset similar with those of other studies conducted internationally, and is therefore able to inform other research based within an ecological theory framework. This research aims to (1) identify evidence for human subsistence strategies, in particular the diversity of marine species types exploited (diet-breadth) and patterns of habitat (patch) exploitation through time; (2) characterise temporal changes in the biomass contribution and population structure of particular species through development of taxa size/age profiles, which identifies, for example, declining efficiencies in marine exploitation and human harvest pressure on resources; and (3) identify and assess changes in marine trophic levels exploited and explore potential evidence of trophic cascades in the local ecosystem in order to determine anthropogenic impacts on local ecologies. The project addresses these aims using methodologies based within an evolutionary ecology framework including the Diet-Breadth Prey Choice Model (MacArthur and Pianka 1966), the Patch Choice Model (Charnov and Orians 1973) and the Central-Place Forager Model (Metcalfe and Barlow 1992). All data are grouped into chronological units of 250-year intervals. While these units offer a broad temporal resolution that may obscure some fine-grained variances in individual datasets, they provide a method for characterising local assemblages in a way that they can be compared across the region (e.g. Ulm 2006). Archaeological evidence indicates that marine shellfish, fish and invertebrates substantially contributed to diet in the South Wellesley Islands. A total of 124.3kg of marine faunal remains are examined for this study. People's foraging strategies were broad-based in terms of both range of habitats accessed and diversity of species collected. 62 molluscan taxa were identified in the study. Hiant venus clam (Marcia hiantina), rock oyster (Saccostrea glomerata), turban snails (Lunella cinerea) and longbums (Telescopium telescopium) were the main molluscs consumed. There is evidence for a long-term trend in changing habitat preferences that could reflect changing cultural preferences and/or changing environments affecting resource availability. From two locations on Bentinck Island we have signals that clearly imply changes in diet-breadth c. 500 cal BP, which were likely a response to an environmental event impacting mangrove habitats and therefore changing taxa abundances available for exploitation. The study characterises the population structure of M. hiantina (the dominant species) through development of the taxon's profile and reviews temporal changes in densities and sizes. Although M. hiantina specimens exhibit some short-term reductions in mean size during seasonal bouts of intensive foraging, temporal patterns indicate that foraging efficiency was not compromised in the long-term. A minimum of 15 species of fish, 1 species of shark and 1 species of turtle were identified from skeletal remains. There is also evidence throughout most periods at most sites of crustacea being foraged although it is difficult to determine numbers. Based on known habitats for the specimens identified (e.g. catfish, grass sweetlip, rockcod, mullet, longtom, whiting, wrasse) much of the fish would have been obtained from hunting in nearshore waters, either from around rocky/coral reefs, intertidal mangroves, estuaries or in the numerous constructed stonewalled intertidal fishtraps. The Central-Place Forager Model was used to explain disparity between ethnographic reports of fishing and hunting activities and the low quantities of fish and vertebrate bones identified in the analysed materials. I contend it is likely dugong, turtle and some fish were processed and consumed at the beach closer to the location of procurement, rather than returned to residential camps (see Tindale 1960:48, 71). Trophic level analysis was used to establish the average trophic level for each 250-year period's marine biomass catch. Faunal data suggest that people targeted primarily the low trophic level shellfish during the early periods of occupation, before shifting their economic focus to a broader-based diet-breadth incorporating more fish, which in turn raised the mean trophic level of all site assemblages. A review of temporal changes in the mean trophic level of exploited resources indicates that hunter-gatherers had little long-term impacts on the overall fishery of the South Wellesley Islands.

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Schäffler, Livia. "Determinants of population structure in the world's smallest primate, Microcebus berthae, across its global range in Menabe Central, Western Madagascar." Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B3B8-1.

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Dissertations / Theses on the topic 'Faunal assemblages'

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