Rozprawy doktorskie na temat „Habitats”

From the Proceedings of the 1989 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 15, 1989, University of Nevada, Las Vegas, Nevada

This is a text about a work of art, “The Room”, and about the process that brought it about. The process includes experiments in clay bodies, mixing different elements with the base clay in search of a material both suitable to work with in terms of texture and color, but also rich in less tangible qualities, as I mix in elements which carry a set of values of cultural identity. The text follows the path towards development of the final piece during the two-year course of the master program at Konstfack. During these two years, external factors such as dealing with the issues of culture shock, and searching for a place to live, interfere with my way of thinking, leading to unexpected turns in the direction of my artistic process. Searching for an apartment finds me standing in strangers' apartments as they sell their homes, their ways of life and their house rules. These sometimes awkward meetings provide a good starting point in my research of people's habits and habitats. In trying to understand some elements of Swedish culture, I become aware of the fact of my own culture and start thinking about it from an outside perspective. Eventually, the central question of the essay crystallizes: Who will carry on the traditional craft techniques of my home country? Romania is the rare place in Europe where crafts are still being practiced as they have been for hundreds of years, in the villages by crafts persons leading traditional lives. As the villages are emptied of young people, moving into cities, and as Romania as a whole is drained of a large part of its young and ambitious generation, moving to other European countries for jobs and education, a trend that I am of course part of, the traditions that I have taken for granted, growing up with my grandmother in a traditional village, become threatened. The answer to the question is a simple as it is demanding: I have to be part of the future of Romanian crafts. To document them, understand them, and incorporate them in my art. For this purpose, I undertake an investigative research trip. The text presents my findings about the crafts, and about the people working to document and preserve the traditions. The research trip is also presented in the movie “Six days in Romania”, which I include as an appendix to the essay. Over the course of two years, several short-term art projects have been completed within the master program. They are presented in the form of an interview with myself. Looking back at these projects, they become explained as necessary steps in preparation for the final piece, a viewpoint very different from the utter confusion that was the dominating feeling of at least the first year of the course. The interview tries to give insight into the non-linear process that is the creative work. Finally, in a poetic description of the final piece, I let my art speak for itself in a very literal way. In giving voice to the piece, I try to access truths hidden even to myself, in an effort to be as transparent as possible about the value of my efforts.

Virtually all marine conservation planning and management models in place or proposed have in common the need for improved scientific rigour in identifying and characterising the marine habitats encompassed. An emerging central theme in the last few years has been the concept of representativeness, or representative systems of Marine Protected Areas (MPAs). The habitat classification and mapping needed to incorporate considerations of representativeness into MPA planning must logically be carried out at the same scale at which management occurs. Management of highly protected areas occurs almost exclusively at local scales or finer, independent of the reservation model or philosophy employed. Moreton Bay, on Australia’s east coast, was selected for studies at the local scale to map and classify macrobenthic habitats. In a site scale (1 km) trial for the major habitat classification study, remote underwater videography was used to map and characterise an unusual assemblage of epibenthic invertebrates on soft sediments. The assemblage included congregations of the comatulid crinoid Zygometra cf. Z. microdiscus (Bell) at densities up to 0.88 individuals.m-2, comparable to those found in coral reef habitats. There was no correlation between the distribution of this species and commonly used abiotic surrogates depth (6 – 18 m), sediment composition and residual current. This site scale trial is the first quantitative assessment of crinoid density and distribution in shallow water soft-sediment environments. The high densities found are significant in terms of the generally accepted picture of shallow-water crinoids as essentially reefal fauna. The findings highlight the conservation benefits of an inclusive approach to marine habitat survey and mapping. Assemblages such as the one described, although they may be of scientific and ecological significance, would have been overlooked by common approaches to marine conservation planning which emphasise highly productive or aesthetically appealing habitats. Most habitat mapping studies rely solely or in part on abiotic surrogates for patterns of biodiversity. The utility of abiotic variables in predicting biological distributions at the local scale (10 km) was tested. Habitat classifications of the same set of 41 sites based on 6 abiotic variables and abundances of 89 taxa and bioturbation indicators were compared using correlation, regression and ordination analyses. The concepts of false homogeneity and false heterogeneity were defined to describe types of errors associated with using abiotic surrogates to construct habitat maps. The best prediction by abiotic surrogates explained less than 30% of the pattern of biological similarity. Errors of false homogeneity were between 20 and 62%, depending on the methods of estimation. Predictive capability of abiotic surrogates at the taxon level was poor, with only 6% of taxon / surrogate correlations significant. These results have implications for the widespread use of abiotic surrogates in marine habitat mapping to plan for, or assess, representation in Marine Protected Areas. Abiotic factors did not discriminate sufficiently between different soft bottom communities to be a reliable basis for mapping. Habitat mapping for the design of Marine Protected Areas is critically affected by the scale of the source information. The relationship between biological similarity of macrobenthos and the distance between sites was investigated at both site and local scales, and for separate biotic groups. There was a significant negative correlation between similarity and distance, in that sites further apart were less similar than sites close together. The relationship, although significant, was quite weak at the site scale. Rank correlograms showed that similarity was high at scales of 10 km or less, and declined markedly with increasing distance. There was evidence of patchiness in the distributions of some biotic groups, especially seagrass and anthozoans, at scales less than 16 km. In other biotic groups there was an essentially monotonic decline in similarity with distance. The spatial agglomeration approach to habitat mapping was valid in the study area. Site spacing of less than 10 km was necessary to capture important components of biological similarity. Site spacing of less than 2.5 km did not appear to be warranted. Macrobenthic habitat types were classified and mapped at 78 sites spaced 5 km apart. The area mapped was about 2,400 km2 and extended from estuarine shallow subtidal waters to offshore areas to the 50 m isobath. Nine habitat types were recognised, with only one on hard substrate. The habitat mapping characterised several habitat types not previously described in the area and located deepwater algal and soft coral reefs not previously reported. Seagrass beds were encountered in several locations where their occurrence was either unknown or had not previously been quantified. The representation of the derived habitat types within an existing marine protected area was assessed. Only two habitat types were represented in highly protected zones, with less than 3% of each included The study represents the most spatially comprehensive survey of epibenthos undertaken in Moreton Bay, with over 40,000 m2 surveyed. Derived habitat maps provide a robust basis for inclusion of representative examples of all habitat types in marine protected area planning in and adjacent to Moreton Bay. The utility of video data to conduct a low-cost habitat survey over a comparatively large area was also demonstrated. The method used has potentially wide application for the survey and design of marine protected areas.

Virtually all marine conservation planning and management models in place or proposed have in common the need for improved scientific rigour in identifying and characterising the marine habitats encompassed. An emerging central theme in the last few years has been the concept of representativeness, or representative systems of Marine Protected Areas (MPAs). The habitat classification and mapping needed to incorporate considerations of representativeness into MPA planning must logically be carried out at the same scale at which management occurs. Management of highly protected areas occurs almost exclusively at local scales or finer, independent of the reservation model or philosophy employed. Moreton Bay, on Australia’s east coast, was selected for studies at the local scale to map and classify macrobenthic habitats. In a site scale (1 km) trial for the major habitat classification study, remote underwater videography was used to map and characterise an unusual assemblage of epibenthic invertebrates on soft sediments. The assemblage included congregations of the comatulid crinoid Zygometra cf. Z. microdiscus (Bell) at densities up to 0.88 individuals.m-2, comparable to those found in coral reef habitats. There was no correlation between the distribution of this species and commonly used abiotic surrogates depth (6 – 18 m), sediment composition and residual current. This site scale trial is the first quantitative assessment of crinoid density and distribution in shallow water soft-sediment environments. The high densities found are significant in terms of the generally accepted picture of shallow-water crinoids as essentially reefal fauna. The findings highlight the conservation benefits of an inclusive approach to marine habitat survey and mapping. Assemblages such as the one described, although they may be of scientific and ecological significance, would have been overlooked by common approaches to marine conservation planning which emphasise highly productive or aesthetically appealing habitats. Most habitat mapping studies rely solely or in part on abiotic surrogates for patterns of biodiversity. The utility of abiotic variables in predicting biological distributions at the local scale (10 km) was tested. Habitat classifications of the same set of 41 sites based on 6 abiotic variables and abundances of 89 taxa and bioturbation indicators were compared using correlation, regression and ordination analyses. The concepts of false homogeneity and false heterogeneity were defined to describe types of errors associated with using abiotic surrogates to construct habitat maps. The best prediction by abiotic surrogates explained less than 30% of the pattern of biological similarity. Errors of false homogeneity were between 20 and 62%, depending on the methods of estimation. Predictive capability of abiotic surrogates at the taxon level was poor, with only 6% of taxon / surrogate correlations significant. These results have implications for the widespread use of abiotic surrogates in marine habitat mapping to plan for, or assess, representation in Marine Protected Areas. Abiotic factors did not discriminate sufficiently between different soft bottom communities to be a reliable basis for mapping. Habitat mapping for the design of Marine Protected Areas is critically affected by the scale of the source information. The relationship between biological similarity of macrobenthos and the distance between sites was investigated at both site and local scales, and for separate biotic groups. There was a significant negative correlation between similarity and distance, in that sites further apart were less similar than sites close together. The relationship, although significant, was quite weak at the site scale. Rank correlograms showed that similarity was high at scales of 10 km or less, and declined markedly with increasing distance. There was evidence of patchiness in the distributions of some biotic groups, especially seagrass and anthozoans, at scales less than 16 km. In other biotic groups there was an essentially monotonic decline in similarity with distance. The spatial agglomeration approach to habitat mapping was valid in the study area. Site spacing of less than 10 km was necessary to capture important components of biological similarity. Site spacing of less than 2.5 km did not appear to be warranted. Macrobenthic habitat types were classified and mapped at 78 sites spaced 5 km apart. The area mapped was about 2,400 km2 and extended from estuarine shallow subtidal waters to offshore areas to the 50 m isobath. Nine habitat types were recognised, with only one on hard substrate. The habitat mapping characterised several habitat types not previously described in the area and located deepwater algal and soft coral reefs not previously reported. Seagrass beds were encountered in several locations where their occurrence was either unknown or had not previously been quantified. The representation of the derived habitat types within an existing marine protected area was assessed. Only two habitat types were represented in highly protected zones, with less than 3% of each included The study represents the most spatially comprehensive survey of epibenthos undertaken in Moreton Bay, with over 40,000 m2 surveyed. Derived habitat maps provide a robust basis for inclusion of representative examples of all habitat types in marine protected area planning in and adjacent to Moreton Bay. The utility of video data to conduct a low-cost habitat survey over a comparatively large area was also demonstrated. The method used has potentially wide application for the survey and design of marine protected areas.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
Full Text

Two designs were developed to model and compare the effects of scale on resource utilization by moose in a managed lodgepole pine (Pinus contorta) forest. Statistical models, based on population and individual design levels (using microsite and moderate polygon habitat scales, respectively), were used to 1) test the hypotheses that moose track presence was increased i) in openings of increasing shrub cover, ii) in forests adjacent to openings of increasing shrub cover, 2) model moose utilization of forest cover, based on distance-from-nearest-opening, to determine appropriate leave strip widths adjacent to openings used by moose, 3) further understanding of how different opening and forest cover types influence moose presence and utilization and 4) compare these results from the different designs. Moose track occurrence and habitat attributes were recorded on 55 snow track transects to model moose presence as a function of distance-from- opening-edge and variation in vegetation cover. Over 15,000 UTM relocations were obtained from 15 GPS collared cow moose over two winters, in the same area. Based on track transect data, the model containing bog birch (Betula glandulosa), Salix species and mean shrub height was the best predictor of moose presence. Resource utilization functions indicated natural and forest management openings, up to 40 years old, were utilised more than older forest habitats. Modeling at both scales confirmed the use of early seral openings (natural or harvested) and indicated that forested distance-from-an-opening-edge does not influence resource utilization or presence of moose. Track presence was greater in wetlands with average shrub cover between 6 - 20% and > 20% than within adjacent forest cover but there was no difference between wetlands with shrub cover < 6% and adjacent forest cover. Tracks were more numerous in forest cover adjacent to wetlands with shrub cover > 20% than in forest cover adjacent to wetlands with shrub cover < 6% and 6 - 20%. The study implies that leave strips may have little immediate effect on the use of early seral openings by moose in winter although, this does not rule out that climate, predation or hunting pressure will influence habitat selection in the future.
Forestry, Faculty of
Graduate

This practice-led research thesis analyses and visualises central components of Authentic Movement, with particular reference to the work of Dr Janet Adler. By contextualising and comparing this improvisation method with modern, post-modern and contemporary movement practices the author describes the emergence of Authentic Movement and distinguishes it from other practices. A new and original viewpoint is adopted and the practice's aesthetic, visual and empathetic characteristics are explored in relationship to and through visual art. The author, a learned Authentic Movement practitioner, critiques, deconstructs and reframes the practice from a visual arts- and performance-based, phenomenological perspective renaming it 'the MoverWitness exchange'. Embedded aspects and skills of the MoverWitness exchange, usually only accessible to firsthand practitioners of the method, are made explicit through research processes of analysis, application and visualisation. Hereby the practice's unique capacity to contain and express binary embodied experiences and concepts is exposed. Resulting insights are crystallised in a distinctive understanding of the MoverWitness exchange that emphasises its suitability as a new learning and/or research methodology for inter- and cross-disciplinary application. Search terms: Arts based research, arts psychotherapy, arts and science, authenticity, authentic movement, binaries, blindness, body, collective body, dance, dance and movement psychotherapy, embodiment, empathy, gastrula, improvisation, interdisciplinary research, mover, MoverWitness exchange, object relation theory, observation, paradigm, performance, phenomenology, sculpture, unconscious choreography, visual art, witness. Janet Adler, James Benning, Trisha Brown, Edgar Degas, Alexander Jawlensky, Tino Sehgal.

Many species require habitats that are naturally patchily-distributed and ephemeral, but human activities fundamentally alter the rate and scale of habitat change. This thesis describes the development of a new metapopulation simulation model applicable to a broad range of species that depend on dynamic habitat. I apply the model to two' case studies, both involving butterfly species that use early-successional habitats and that are UK BiodiversIty Action Plan priority species. I describe. two methods for parameterising the model for a particular metapopulation in a particular landscape. One method uses parallel disturbance ar:d population presence data for a few consecutive years; the other derives population parameters and landscape parameters from separate data sources. In the first case study, I found that the BAP target for Heath Fritillary (Melitaea athalia) populations in the Blean Woods, Kent, could either be met by approximately doubling the coppicing effort, or by concentrating the existing effort into one of the larger woodland blocks. In the second case study, I found that the rate of heathland burning in the South Stack area of Angl~seywas not enough by itself to sustain the metapopulation of Silver-studded Blues (Plebejus argus). However, the metapopulation is probably saved from extinction by the existence of permanently-suitable habitat close to the coast. I have also elucidated an important phenomenon in metapopulations with dynamic habitat: the relationship between patch occupancy and patch connectivity can be obscured by the temporal changes in habitat. This has important implications for the debate about whether many real populations actually fit the metapopulation paradigm because the existence of metapopulation dynamics is often determined by testing the connectivity-occupancy relationship. The simulation model, 'MANAGE', is an important new tool for integrating landscape-scale information, and answering conservation questions, in a field which is relatively new and unexplored.

Micro-organisms are the most abundant and diverse form of life on Earth. Their ability to tolerate stress has enabled them to colonise many inhospitable environments. Microbial processes alter the chemistry of the environment which has left a lasting mark on the geological record. On the other hand, microbial life is heavily influenced by environmental conditions. Indeed, the history of the Earth is shaped by the co-evolution of microbial and geological processes. This thesis explores how micro-organisms are influenced by their environment, with particular reference to microbial rock habitats. Rock habitats are an interesting system to understand the inter-relationship between microbial life and it's environment as they are relatively simple and very common. Rock-dwelling communities are also exposed to numerous stresses such as surface UV exposure, desiccation, temperature fluctuations, low nutrient availability or toxicity from elements leached from the rocks themselves. Three specific aspects of microbial stress in rock environments are investigated here: 1) The use of rocks as a shield from surface UV radiation stress, 2) The microbial response to chemical changes during water-rock interactions, 3) The effect of simultaneous limitation of more than one nutrient. The first uses exposure facilities aboard the International Space Station to provide empirical evidence that colonisation of the early land masses by phototrophs was not inhibited by high surface UV radiation. The latter studies use quantitative proteomics to investigate the cellular response of a heterotrophic bacterium to nutrient deficiency and element leaching, two common stresses in rock habitats. Together these results further our understanding of the relationship between micro-organisms and rocks, both today and over geological time.

Coastal lagoons and their habitats perform an important nursery function for marine migrant (MM) fish species, which enter in these ecosystems to exploit the abundant trophic resources and the best biotic and abiotic conditions. The aim of this work is to study the nursery function carried out by shallow water habitats of the Venice lagoon, i) studying the sea-lagoon connectivity, ii) studying and characterizing the habitat preferences, iii) studying the trophic ecology of a target species (Sparus aurata). In this work: i) analyzing the distribution of eggs, larvae and juveniles, collected with a bongo net and a seine net in the whole Venice lagoon, it was possible to observe that the north sub-basin is the one where MM are more concentrated, ii) developing predictive models on distribution of juveniles MM in different habitats of the north sub-basin, it was possible to observe how preferences towards environmental parameters and habitats change with ontogeny but in general saltmarshes were positively selected iii) analyzing diet, head morphology and stable isotope of S. aurata during ontogeny it was possible to observe the importance of tidal creek for the trophic ecology of this MM species. Only through the integration of these methods it is possible to evaluate the complex nursery function of the lagoons, to direct the actions of restoration and management.

Submitted by Morgana Andrade (morgana.andrade@ufes.br) on 2016-07-04T20:10:54Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Secchin_Final.pdf: 4693409 bytes, checksum: 5679a36c3571a5915a720d1300aa6169 (MD5)
Approved for entry into archive by Patricia Barros (patricia.barros@ufes.br) on 2016-07-08T17:33:05Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Secchin_Final.pdf: 4693409 bytes, checksum: 5679a36c3571a5915a720d1300aa6169 (MD5)
Made available in DSpace on 2016-07-08T17:33:05Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação_Secchin_Final.pdf: 4693409 bytes, checksum: 5679a36c3571a5915a720d1300aa6169 (MD5)
A plataforma continental tropical é composta por um mosaico de megahabitats que suportam uma alta diversidade de habitats, e atualmente vêm sofrendo com as pressões antrópicas. O desenvolvimento e a aplicação de geotecnologias em estudos de mapeamento do substrato marinho vêm proporcionando um aumento no conhecimento dos habitats bentônicos. Importante formação coralínea do Atlântico Sul, a Plataforma dos Abrolhos, não possui informações suficientes que possibilitem uma gestão efetiva. O presente estudo tem com objetivo apresentar uma distribuição espacial e caracterização dos domínios dos principais megahabitats da Plataforma dos Abrolhos. Para tal, foram utilizados dados diretos e indiretos de investigação geológica, com uma combinação metodológica englobando levantamentos de SVL, ecobatímetro monofeixe e ROV, sendo base para uma classificação hierárquica dos megahabitats e integração com dados pretéritos levantados. Alcançando uma representação interpretativa dos tipos de fundo da região estudada (50.500km²), a aplicação metodológica possibilitou gerar uma nova visão para a Plataforma dos Abrolhos. Foram identificados os domínios de megahabitat Recifal (17%), Rodolito (51%), bem como as principais feições de cada um, ocorrendo com variações na distribuição e ocorrência em relação à disposição ao perfil batimétrico. Uma estrutura recifal que ocorre juntamente com o domínio de rodolitos, as Buracas, é um habitat particular que pode ter uma importância significativa para o ecossistema de Abrolhos. A metodologia aplicada foi satisfatória na geração de uma representação da distribuição e descrição de megahabitats marinhos para toda a Plataforma dos Abrolhos. Oferecendo, assim, uma nova abordagem em estudos de delineamento de habitats marinhos aplicados na costa brasileira, sendo importante pela área espacial representada, contida em uma região singular onde havia uma lacuna no conhecimento sobre a distribuição e caracterização deste habitat em toda a sua extensão.
The continental shelf is composed of a tropical mosaic megahabitats that support a high diversity of habitats, and now have suffered from anthropogenic pressures. The development and application of geo-mapping studies of the marine substrate has provided increased knowledge of benthic habitats. The most important coral reef formation of the South Atlantic, Abrolhos Platform, does not have sufficient information to enable effective management. The present study aims at presenting a spatial distribution and characterization of the major fields of the Platform of the Abrolhos' megahabitats. To this end, we used data from direct and indirect geological research, with a combination of surveys covering methodological SSS, and echo sounder, ROV, and the basis for a hierarchical classification of megahabitats and integration with past data collected. Reaching an interpretative representation of the types of background of the region studied (50.500km²), the methodological application was able to generate a new vision for the Platform of the Abrolhos. We identified areas of reef megahabitat (17%), Rhodolite (51%) as well as the main features of each, with variations occurring in the distribution and occurrence in relation to the available bathymetric profile. A reef structures that occurs with the domain Rhodolite, the Buracas, is a particular habitat that may have a significant importance for the ecosystem of Abrolhos. The methodology was applied to generate a satisfactory representation of the distribution and description of marine megahabitats for the entire Abrolhos Platform. Thus offering a new approach to design studies of applied marine habitats along the Brazilian coast, is important for the space represented, contained in a unique region where there was a gap in knowledge about the distribution and characterization of this habitat throughout its length.

Two widely-recognised hypotheses propose that increases in fish abundance at artificial reefs are caused by: (a) the attraction and redistribution of existing individuals; and/or (b) the addition of new individuals by production. Inadequate experimental designs compromised by a lack of sufficient replication and/or spatial interspersion of reefs with controls have prevented researchers from distinguishing between attraction and production. Infrequent sampling has also led to insufficient temporal coverage of life history-driven variations in fish abundance and biomass at reefs. Detection and resolution of these trends, together with incorporation of fish age/length data, and the use of techniques such as stable isotope analysis to infer trophic link(s) between reef residents and potential sources of epibenthic nutrition at reefs should help demonstrate mechanisms underlying attraction and/or production. Given that fish numbers tend to increase after artificial reef deployments, artificial reefs have been proposed as a means by which fish stocks could be enhanced by providing new habitat in areas where natural habitat vital for feeding, shelter and reproduction have been removed, such as residential canals. The purpose of my study was to investigate whether or not artificial reefs could be used to enhance fish production within residential canals. Five reefs were deployed into Lake Rumrunner on the Gold Coast in southeast Queensland, Australia (28°02’59”S, 153°25’19”E). Reefs were interspersed among five soft sediment (control) sites of similar depth. Fish assemblages at reefs, controls and shoreline jetties were quantitatively sampled using a modified seine pop net. Very few fish were recorded at controls, but fish abundance and biomass increased dramatically at reefs shortly after deployment, stabilising at levels above that of shoreline jetties. Reefs and jetties accommodated different fish assemblages and assemblage structure varied through time. Multivariate analyses indicated that the fish assemblage at jetties within Lake Rumrunner differed from assemblages at jetties in adjacent lakes in terms of biomass composition, accommodating numerous individuals of small-bodied species. The fish assemblage at reefs featured individuals of large-bodied species and occasional, itinerant individuals of species typical of offshore subtidal reefs. Among co-occurring (reef and jetty) fish species, strong differences in the distribution of Monodactylus argenteus (Monodactylidae) between reefs, jetties and controls suggested possible new production driven by reef deployment. Abundance and biomass of M. argenteus was significantly greater at reefs relative to controls (where no fish were caught) and jetties at all times after deployment. Individuals were consistently larger on reefs than on jetties. Analyses of length-frequency distributions through time indicated the size of individuals differed from one sampling time to the next for most sampling times at reefs, possibly representing cohort growth and movement through time...
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment
Science, Environment, Engineering and Technology
Full Text

En 1992 en Europe, grâce à la Directive Habitats-Faune-Flore, les habitats naturels sont devenus des objets à conserver au même titre que les espèces, élargissant ainsi le domaine d’actions des politiques publiques à un autre niveau d’organisation de la biodiversité. Mais la reconnaissance tardive de leur valeur de conservation, ainsi que des lacunes dans leurs définitions sont en partie responsables de l’absence de séries temporelles de données sur les habitats à l’échelle nationale. Cela limite notre capacité à surveiller et évaluer leur état de conservation, et à adapter les actions de conservation aux niveaux national et local. Les objectifs de cette thèse sont d’abord d’explorer des approches rapides et formalisées de reconnaissance des habitats forestiers afin de pouvoir ensuite étudier leur dynamique récente au regard de deux grands changements survenus au cours des dernières décennies : le réchauffement climatique et la création du réseau Natura 2000.Nous avons d’abord étudié les incertitudes liées à la reconnaissance des habitats forestiers lors du rattachement d’un relevé floristique à un type d’habitat en comparant cinq experts et trois programmes automatiques de classement. Nous avons mis en évidence la forte variabilité de classement entre experts, et l’efficacité des programmes automatiques qui est comparable à celle des experts. Nous avons également montré que pour la reconnaissance des habitats forestiers, un nombre limité d’espèces est suffisant, et qu’il est possible d’utiliser des relevés réalisés en hiver. Ainsi, nous avons pu créer des séries temporelles de données standardisées sur les habitats forestiers à partir de différentes sources d’inventaires floristiques, rattachés ou non à un type d’habitat.Dans un second temps, la création de 5701 couples de relevés floristiques historiques (avant 1987) et récents (après 1997) a permis de mettre en évidence, en montagne, un changement de 11% des couples vers des habitats forestiers caractéristiques de conditions climatiques plus chaudes. L’augmentation de la dominance de ces habitats nous permet de conclure à une thermophilisation des habitats forestiers en montagne. Cependant, aucun changement significatif n’a été observé en plaine, ce qui conduit à un décalage important entre les exigences thermiques des communautés végétales et les températures actuelles : une dette climatique se développe. Face à des impacts différenciés, nous concluons que les politiques publiques pourraient être mises en place et priorisées de façon différente en montagne et en plaine pour être plus efficaces.Enfin, en étudiant 155 sites Natura 2000 français répartis sur tout le territoire métropolitain tempéré et montagnard, nous avons montré que, depuis la mise en place du réseau, l’augmentation de la quantité des très gros bois sur les zones où ils sont présents est significativement plus forte à l’intérieur du réseau Natura 2000 qu’à l’extérieur. Ainsi, nous avons mis en évidence que les actions de conservation mises en place dans les forêts au sein du réseau Natura 2000, qui sont gérées et exploitées, ont déjà eu des effets positifs sur les très gros bois, considérés comme une caractéristique de vieilles forêts, et utilisés aussi comme indicateur de biodiversité et du bon état de conservation des habitats forestiers.Ce travail de thèse était nécessaire pour compléter les nombreuses études déjà disponibles à l’échelle des espèces et des communautés végétales, car pour être efficace il est indispensable de travailler à la conservation de tous les niveaux d’organisation de la biodiversité simultanément. Connaitre les domaines de validité des moyens de reconnaissance des habitats forestiers, mais aussi comprendre leur dynamique récente et les facteurs qui l’influencent permettent de fournir des éléments pour mettre en place un suivi des habitats forestiers et adapter les politiques publiques et les actions de gestion afin d’en améliorer l’efficacité
In 1992, European natural habitats became items to be conserved in the same way as species were, thanks to the Habitats Directive. This enlarged the scope of action of nature protection public policies to a new level of biodiversity organisation. But the late recognition of the conservation value of habitats and the gaps in their definitions partly explain the absence of time series data at the national scale. This limits our capacity to monitor and assess their conservation status and to adapt conservation measures at the national and local levels. The present thesis work first investigates rapid, formalised approaches for identifying forest habitats. Then, these approaches are used to study the recent dynamics of forest habitats in relation to two substantial changes that occurred in the past decades, i.e., climate warming and the creation of the Natura 2000 network.We first studied the uncertainties linked to the identification of forest habitats when assigning floristic surveys to habitat types by comparing five expert’s judgements with three automatic classification programs. We highlighted high variability among expert judgements, and comparable efficiency between automatic classification programs and expert judgements. We also demonstrated that a limited number of species was sufficient to identify forest habitats, and that surveys carried out in winter could be used too. We thus created time series of standardised data on forest habitats based on different floristic survey sources, whether assigned to a habitat type or not.Secondly, we created 5,701 pairs of historical (before 1987) and recent (after 1997) floristic surveys, and highlighted that 11% of the pairs located in highlands had shifted towards forest habitats characteristic of warmer climate conditions. The increased dominance of these habitats led us to conclude that thermophilisation was underway in highlands. However, no significant shift was observed in lowlands, hence a substantial difference between the thermal requirements of plant communities and current temperatures: a climatic debt is developing. In the face of these different impacts, we proposed that nature protection public policies could be more efficient if they were implemented and prioritised differently in highlands vs. lowlands.Finally, we studied 155 Natura 2000 sites distributed across mainland temperate and mountainous France, and showed that the number of very large trees in the plots where they were observed had increased significantly more inside the network than outside it since its implementation. We thus evidenced that the conservation measures implemented in Natura 2000 forests, which are managed and exploited, have already had positive effects on very large trees – considered as a characteristic of old-growth forests and also used as biodiversity and conservation status indicators of forest habitats.This thesis work was necessary to complement the numerous studies already available at the species and plant community scales, for it is indispensable to aim for the simultaneous conservation of all the levels of organisation of biodiversity to be efficient. Knowing the scope of validity of the tools used to identify forest habitats, but also understanding the recent dynamics of forest habitats and its influencing factors provide useful data to implement surveillance and adapt public policies and management actions, and thereby reach greater efficiency

This project develops a collaborative telecommunications project called Habitats Online. Review of the literature indicates that collaborative telecomunication projects, like Habitats Online, engage students in rich learning experiences and establish a network of future citizens who have a greater understanding of our environment and global communications. This master's project specifically addresses these issues.

The Mediterranean sea, just like the rest of the world seas, is facing a whole new variety of pressures related to human activities; vulnerable species and habitats are already being altered by such pressures. Among Mediterranean biocenoses, the coralligenous reefs, mid-water calcareous bioconstructions, are especially vulnerable. For these reasons it is needed to build a solid knowledge about the relations that underlie climate and biological organisms. A convenient way to address these issues is trough numerical models becausse they allow for generality to emerge and are suitable tools for predictive purposes. This thesis presents a collection of contributions focused on marine calcifiers from Mediterranean coralligenous habitats. Various aspects of ecology and phisiology are addressed at various scales in both time and space trough numerical applications.

Riparian systems are important for breeding bird communities and are highly used as migratory corridors; however, their importance for wintering birds has not been assessed systematically. In order to assess the value of riparian areas for birds wintering in Sonora, data from 1,816 standard point counts were collected from 87 locations during January and February 2004-2006. A total of 253 species were detected across 14 vegetation types, including nine categories of riparian vegetation. The mean number of species and individuals detected per count was significantly higher in riparian vegetation than in non-riparian vegetation for migratory species, but not for residents. Riparian bird communities are different from those in non-riparian habitats, and contribute 22% of the regional avifauna's species.
Anthropogenic disturbance has imposed significant changes in riparian habitats, and is known to have negative effects on biological communities. To assess the effects of human induced disturbance on wintering bird communities, I recorded community composition, relative abundance of species, and three indicators of bird condition in relatively undisturbed and highly disturbed sites at three river systems in Sonora. There is, in general, little effect of disturbance on the composition of wintering communities, with less than 20% of the most common species having significant differences in their abundances between relatively undisturbed and highly disturbed sites. Condition indicators were similar in the two disturbance levels, but the mean heterophil/lymphocyte ratio in the blood of sampled birds showed increased levels of physiological stress in disturbed sites. A more experimental approach is needed to determine the specific cause of the stress expression in leucocytes.
Modification of natural flooding regimes has modified riparian areas, as has been the case in the Colorado River Delta. I present a summary of the changes experienced by riparian systems and some of the measures implemented for riparian restoration in the southwestern United States, and then I compare the scenario with that in central Sonora, where some of the same stressors exist on riparian systems, but where traditional management practices have also mitigated some of the negative consequences of flow control along mid-sized river systems.

The deep sea represents the largest biome on earth, and for most of it, no maps of resolutions comparable to terrestrial environments are available. As new species continue to be discovered, it is clear that our knowledge of species spatial patterns is insufficient to properly inform marine spatial planning, and for complex habitats, high-resolution surveys are crucial for understanding species-environment relationships. This thesis examined two deep-sea areas of the NE Atlantic, Rockall Bank and Whittard Canyon. By linking acoustic maps to benthic imagery datasets, environmental variables describing the spatial arrangement of different substratum types and topographic variability were found to be good predictors of species composition and biodiversity. Employing an ensemble of statistical techniques provided a more robust approach for the creation of biological full-coverage predictive maps and allowed for the identification of areas with high biodiversity. With these maps, it was possible to demonstrate that biological spatial patterns in Whittard Canyon required mapping resolutions of 20-50m while the more heterogeneous Rockall Bank area needed to be mapped at <5m. The continued sparse availability of biological datasets in the deep-sea remains a significant limiting factor in informing conservation needs, but the work carried out shows improvements over previous approaches, and can be applied to identify biodiversity hotpots and assess habitat suitability for vulnerable marine ecosystems, such as cold-water corals. Through such hierarchical multi-disciplinary studies, the currently available biological information can be employed to increase our understanding of the relationships between habitat heterogeneity and biodiversity as well as help establish the baseline state of these ecosystems in order to effectively monitor potential impacts.

The following four broad aims were addressed in this study. (1) To ascertain whether the characteristics of the benthic macroinvertebrate assemblages within the different nearshore marine habitat types identified by Valesini et al. (2003) on the lower west coast of Australia differ significantly, and whether the pattern of those spatial differences matches those among the environmental characteristics that were used to distinguish those habitat types; (2) To develop a quantitative approach for classifying nearshore habitats in estuarine waters that employs readily-available data for a range of enduring environmental characteristics, and to use that approach to classify the various habitat types present in nearshore waters of the Swan-Canning Estuary on the lower west coast of Australia; (3) To test the hypothesis that the characteristics of the benthic macroinvertebrate assemblages in the in the Swan-Canning Estuary differ significantly among nearshore habitat types, and that the pattern of those differences matches that among the environmental characteristics used to distinguish those habitat types and (4) To test the hypothesis that, as a result of environmental changes in the Swan-Canning Estuary, the characteristics of the benthic macroinvertebrate assemblages at various habitats in this estuary in 1986/7 differ from those in 2003/4. To address the first aim, benthic macroinvertebrates were sampled seasonally for one year in the subtidal waters and intertidal zone (upper and lower swash zones) at the six nearshore habitat types that were identified by Valesini et al. (2003) on the lower west coast of Australia. The habitat types, which differed mainly in the extent of their exposure to wave activity and whether seagrass and/or nearshore reefs were present, had been distinguished quantitatively using values for a suite of seven statistically-selected enduring environmental characteristics. The faunal samples yielded a total of 121 species representing eight phyla, among which the Polychaeta, Malacostraca and Bivalvia were the most speciose classes and contributed ~ 38, 23 and 10%, respectively, to the total number of individuals. The total number of species and mean density of macroinvertebrates was far greater at the most protected habitat type (1), which also contained dense beds of seagrass, than at any other habitat type, i.e. 70 species and 209.2 individuals 0.1 m-2, compared to 32 species and 36.9 individuals 0.1 m-2 at the most exposed habitat type (6), which had a substrate comprised only of sand. Differences among habitat type influenced the benthic macroinvertebrate species composition to a greater extent than differences among either zones or seasons. Significantly different faunal compositions were detected among those latter two factors only at the most protected habitat type. The faunal assemblage at habitat type 1 was clearly the most distinct from those at the other five habitat types, particularly in the subtidal zone (R-statistics=0.642-0.831, p=0.1%), and was typified by five abundant polychaete species that were adapted to deposit-feeding. In contrast, the fauna at habitat type 6 was typified by four crustacean species and a species of bivalve and polychaete, whose mobility and tough external surface facilitated their survival and feeding in those turbulent waters. The extents of the differences in species composition among the six habitat types was significantly matched with that among the suite of enduring environmental characteristics that distinguished those habitat types, particularly in the case of the subtidal zone (Rho=0.676). Such results indicated that the environmental variables used to distinguish the nearshore habitat types could be used to reliably predict the types of benthic macroinvertebrate species likely to occur at any site along the lower west coast of Australia. The above biological validation of the nearshore marine habitat classification scheme developed by Valesini et al. (2003) provided the justification for the approach to the second broad aim of this study, namely to develop a quantitative scheme for classifying habitat types in the Swan-Canning Estuary. This approach was similar to that employed by Valesini et al. (2003) in that it considers that differences among habitat types are well reflected by differences in a suite of enduring environmental variables. However, it improves on that earlier method by employing a completely objective and quantitative approach. Thus, a large number of environmentally-diverse nearshore sites (102) were initially selected throughout the Swan-Canning Estuary and a suite of 13 enduring environmental variables quantified at each using remotely-sensed images of the estuary in a Geographic Information System. Such variables were chosen to reflect either (i) the type of substrate and submerged vegetation present, (ii) the extent of exposure to wave action or (iii) the location of the site within the estuary with respect to its vicinity to marine and fresh water sources. These data were then subjected to the CLUSTER routine and associated SIMPROF procedure in the PRIMER v6 multivariate statistical package to quantitatively identify those groups of sites that did not differ significantly in their environmental characteristics, and thus represented habitat types. Eighteen habitat types were identified, which were shown to well reflect spatial differences in a suite of non-enduring water quality and sediment characteristics that were measured in situ at a range of estuarine sites during both summer and winter in 2005 (Rho=0.683 and 0.740, respectively, p=0.1%). However, those latter environmental characteristics required far more time in the field and laboratory to quantify than the enduring variables used to identify the habitat types. Benthic macroinvertebrates were sampled during summer and winter in 2005 in the shallow subtidal regions (~1 m depth) at sites representing eight of the habitat types identified in the Swan-Canning Estuary. These samples contained a total of 51 and 36 species during summer and winter, respectively, and, in both seasons, represented nine phyla, namely Annelida, Crustacea, Mollusca, Sipuncula, Nematoda, Platyhelminthes, Cnidaria, Uniramia and Nemertea. The compositions of the benthic macroinvertebrate assemblages differed significantly among habitat types and, to a similar extent, between seasons (Global R-statistic=0.408 and 0.409, respectively, p=0.1%). However, the spatial differences were considerable greater in winter than in summer (Global R-statistic=0.536 vs 0.280, p=0.1%), presumably due to the greater spatial variation in particular non-enduring in situ environmental characteristics, such as redox depth and salinity. While the number of species, overall density and taxonomic distinctness of benthic macroinvertebrates also differed significantly among habitats, those variables differed to a greater extent between seasons, being greater in winter than in summer. While the measures of taxonomic distinctness tended to be greater at habitat types located in the lower to middle reaches, i.e. habitat types 6, 7, 9, 10, 13 and 18, than the upper reaches i.e. habitat types 1 and 3, the number of species and overall density reflected this trend only during winter. During summer, the mean numbers of species at habitat types 1, 3, 6 and 10 (3.4-6.0) were significantly lower than those at habitat types 7, 13, and 18 (8.8-10.9), whereas the overall density of benthic macroinvertebrates was far greater at habitat type 7 (32260 individuals 0.1 m-2)than at any other habitat type in this season (3135-18552 individuals 0.1 m-2). Overall, the greatest differences in assemblage composition occurred between those at habitat types 1 and 18 (R-statistic=0.669, p=0.1%), which were located in the uppermost region of the estuary and the lower reaches of the basin, respectively, and differed to the greatest extent in their enduring environmental characteristics. The assemblage at habitat type 1, and also that at habitat type 3, located just downstream, were relatively distinct from those at all other habitat types, particularly during winter (R-statistics=0.666-0.993, p=0.1%). The fauna at the first of these habitat types was relatively depauperate, containing low numbers of species and densities, and was characterised by the polychaetes Leitoscoloplos normalis and Ceratonereis aequisetis and the bivalve Arthritica semen. The assemblage at habitat type 3 was also characterised by those three species and the amphipod Paracorophium minor and the polychaete Boccardiella limnicola. In contrast, the assemblage at habitat type 18 was characterised by a more diverse assemblage, i.e. the polychaetes Capitella capitata, C. aequisetis, L. normalis and Pseudopolydora kempi, the amphipods, Grandidierella propodentata and Corophium minor and the bivalve Sanguinolaria biradiata. The number of species was among the highest at this habitat type during both seasons, which was also reflected in the high taxonomic diversity, and the overall density was the highest in winter and second highest in summer. Despite the above faunal differences, those between assemblages at habitat types 7 and 9, which were both located in the basin of the Swan-Canning Estuary, were similar in magnitude to those that occurred between pairs of habitat types located in two different regions of the estuary. Although both habitat types 7 and 9 were characterised by a similar suite of species, i.e. Oligochaete spp., C. aequisetis, C. capitata, C. minor, G. propodentata, L. normalis, and S. biradiata, the substantial differences in assemblage composition between these habitat types in both summer and winter (R-statistics=0.570 and 0.725, respectively) was due to marked differences in the relative contributions of each of these species. Significant and strong correlations were shown to exist in both summer and winter between the pattern of differences in the benthic macroinvertebrate assemblages among habitat types and that among the enduring environmental characteristics used to identify those habitat types (Rho=0.625 and 0.825, respectively, p=0.1%). Furthermore, these correlations were greater than those obtained between the benthic macroinvertebrate fauna and any combination of the non-enduring environmental characteristics (i.e. water quality and sediment parameters) recorded in situ at each habitat type (Rho=0.508 and 0.824, in summer and winter, respectively, p=o.1%). This demonstrates the greater capacity of surrogate enduring environmental characteristics to account for differences in the range of variables that may influence the distribution of benthic invertebrate fauna. Thus, the lists of characteristic benthic macroinvertebrate taxa produced for each of the eight habitat types studied in the Swan-Canning Estuary provide a reliable benchmark by which to gauge any future changes in those fauna. Moreover, these results indicate that the above habitat classification scheme can be used to reliably predict the types of benthic macroinvertebrate fauna that are likely to occur at any nearshore site of interest in this estuarine system. The final component of this study showed that the benthic macroinvertebrate assemblages at four sites in the middle reaches of the Swan-Canning Estuary in 2003/4 differed significantly from those recorded at the same sites in 1986/7. Such differences were reflected in (1) changes in the relative densities of a suite of ten species that were responsible for distinguishing the faunas in these two periods, (2) the absence of 22 rare species in 2003/4 (i.e. 42% of the number of species recorded in 1986/7), (3) the presence of 17 new species in 2003/4, including an abundant polychaete that is likely to have been introduced and (4) a far greater extent of seasonal variation in the number of species and densities of benthic macroinvertebrates in 2003/4. Such changes are likely to be related to lower sediment oxygen levels in certain seasons in 2003/4, as well as an altered hydrological regime due to increased temperatures and decreased rainfall in that more recent period. The fact that these changes have occurred within the Swan-Canning Estuary highlights the need for effective management tools, such as the habitat classification scheme and associated faunal survey undertaken in this study. Such data will provide a sound basis by which to examine the ways in which fauna vary spatially within the system, and allow for the establishment of comprehensive benchmarks for detecting future changes.

In this dissertation, I experimentally examine predation-induced mortality upon juvenile queen conch, Strombus gigas, and assess the importance of select habitat predator and conch characteristics affecting predation intensity. Experiments were conducted during the summer and early fall of 1987, 1988, 1990 and 1991 in seagrass beds and adjacent sand flats near Lee Stocking Island, Exuma Cays, Bahamas. These experiments indicate that various factors act interactively to produce habitat-specific mortality rates in queen conch due to predation. These include (1) habitat type, whereby seagrass beds offer some protection; (2) local population dynamics, such that populated seagrass beds appear to enhance conch survival; (3) population density in some seagrass beds, such that mortality is inversely density-dependent; (4) conch size, such that larger conch have higher survival rates, depending on the specific type of habitat; and (5) predation intensity and predator guilds, which likely differ across habitats, producing habitat-specific mortality rates. When integrated with complementary studies of queen conch trophodynamics, these results provide critical information regarding key ecological factors affecting conch survival. In particular, results from the hatchery-reared experiments demonstrate the potential use of hatchery-reared stocks in natural habitats, and hence a valuable option for enhancement of fishery stocks throughout the Caribbean. In general, the integration of results obtained in this dissertation, with complementary studies of queen conch trophodynamics, should provide valuable suggestions of queen conch habitats, densities and scales of patchiness producing highest survivorship and growth rates in nature.

Thesis (MSc (Conservation Ecology and Entomology))--University of Stellenbosc, 2005.
Biodiversity is under enormous pressure from an increasing human population. Urbanisation, agriculture, and mining are just some of the factors responsible for the continuous degradation of the natural environment. Of these, urbanisation is one of the leading factors of diversity loss. To address this problem, it is necessary to understand the relationship between biodiversity and urban areas, as well as the relationship between society and biodiversity. This study focuses on these relationships and suggest ways in which urban biodiversity can be maximised without compromising on development. In order to create an urban environment that successfully supports maximised biodiversity, new methods and ideas must be developed to promote the protection of urban ecosystems. The Cape Floristic Region in South Africa is a good example of an area that requires immediate action in order to prevent enormous losses in biodiversity. Data have shown drastic decreases in natural vegetation cover in this area, and with its close to 9000 species, of which approximately 60% occurs nowhere else in the world. This state of affairs should be regarded as a serious crisis. This study consists of three main parts, the first being a literature review on the current relationships between the urban environment, society, and biodiversity. The second and third parts report on two empirical investigations on the campus of the Faculty of Health Sciences at the University of Stellenbosch in the City of Cape Town. The first of these investigates the possibility of using spirituality connected to nature as a promotional tool for conservation through rehabilitation or restoration of damaged urban vegetation habitats. For this purpose students’ and staff members’ opinions of the urban nature at the campus were tested. In the second investigation the options of restoring biodiversity to the campus was considered by exploring the best options available for rehabilitation while taking the current biodiversity status on and around the premises into account. This was carried out through three smaller projects that included the physical reintroduction of plant species, vegetation analysis, and bird identification and attraction. The response of employees and students at the Faculty of Health Sciences was found to be in favour of restoring vegetation and animal life to the campus. This is supported by a belief that their attitude towards their work would improve with improved natural surroundings. Initial rehabilitation attempts highlighted the complexity of rehabilitation practices by bringing forward challenges and problems experienced with the reintroduction of plant species. Despite these problems, increased plant diversity in experimental areas showed the possibility of successfully completing the project. Biodiversity analysis showed that methods of controlling vegetation used by the university are doing more harm than good, as it results in indigenous vegetation being displaced by exotic vegetation. This study introduces a number of questions regarding the relationship between urbanisation and biodiversity and to what extent the two should be linked. Hopefully it is a step in the direction towards marrying the urban and natural environment, and to create a sustainable urban environment where society no longer sees nature as something outside the city boundaries.

Dimethylsulphoniopropionate (DMSP) is a dimethylated sulphur compound that appears to be produced by most marine algae and is a major component of the marine sulphur cycle. The majority of research to date has focused on the production of DMSP and its major breakdown product, the climatically important gas dimethylsulphide (DMS) (collectively DMS/P), by phytoplankton in the open ocean. A number of functions for intracellular DMSP (DMSPi) in phytoplankton have been identified and the cycling of DMS/P appears to be critical for ecosystem function. However, mechanisms for the production and release of DMS/P in the coastal ocean are poorly understood, despite the region’s economic and ecological importance. Coralline algal habitats (e.g. maerl beds, coral reefs, seagrass meadows, kelp forests) are distributed throughout the coastal oceans worldwide. Their three-dimensional structure supports high biodiversity and provides numerous services, generating considerable economic wealth. DMSPi in coralline algae is known to be high, thus coralline algal habitats may be critical components of the coastal sulphur cycle. This research aimed to improve our understanding of the production of DMS/P by coralline algal habitats by investigating (1) natural spatiotemporal variation and (2) the influence of environmental pressures. This was achieved through a number of laboratory and field-based studies, utilising modern and well-established techniques. The first objective of this research was to better understand the photosynthesis of red coralline algae (Chapter 3), as the algal precursor to DMSPi is methionine, a product of photosynthesis. The photosynthetic characteristics of coralline algae exhibited acclimation to changing light conditions (e.g. over a diurnal cycle or between natural and static lighting conditions). Further, for the species tested, coralline algae are often subjected to light-saturating natural conditions, therefore requiring efficient photo-protective mechanisms, which may include DMSPi regulation. On a global scale, DMSPi in coralline algae may decline with latitude, reinforcing the role of DMSPi as an antioxidant (Chapter 4). At smaller spatial scales, DMS/P production, release and recycling mechanisms were apparent in a number of habitat types (Chapter 4). A strong seasonal trend in DMS/P was also observed at a Scottish maerl bed, driven by water temperature and cloud cover (Chapter 5). Annually averaged DMS and DMSP concentrations were 230% and 700% respectively higher than the open ocean, highlighting the potential importance of the coastal ocean in the marine sulphur cycle (Chapter 5). The influence of environmental pressures (decreased salinity, variable pH and grazing) on DMS/P production by coralline algal habitats was examined (Chapters 6 – 8). In agreement with the phytoplankton literature, a chronic, but not acute, reduction in salinity led to a significant decline in coralline algal DMSPi concentrations and a sinking of the surface epithelial cells but no apparent impact on photosynthesis (Chapter 6). In the naturally variable tropical reef environment, calcifying algae continually regulated DMSPi concentrations in response to the diurnal cycling of carbonate saturation state (Chapter 7), suggesting that DMSPi may be enhanced under low pH regimes to compensate for enhanced oxidant production. Under low pH conditions, cracks were observed between the surface epithelial cells of coralline algae, potentially allowing DMSPi to leak from the cells (Chapter 7). In the field, grazing by urchins appeared to facilitate the release of DMS/P from kelp in coralline algal habitats (Chapter 8). In the laboratory, DMSPi in coralline algae increased in response to chemical cues from grazers rather than direct grazing activity, as had been previously proposed. Prior to this research, little information was available on DMS/P concentrations in coralline algal habitats. The marine sulphur cycle may impact climate regulation and ecosystem function on a global scale. This research provides a comprehensive source of information on the importance of coralline algal habitats in the marine sulphur cycle by examining natural variability and potential changes in response to environmental perturbations. This work will form a baseline for continued research in this field, investigating, for example, the impact of multiple stressors on DMS/P production, release and recycling in coastal marine habitats.

Cold-water corals are found globally but little is known about energy flows associated with these habitats. The degree to which the benthic ecosystems containing cold-water corals are linked to the overlying pelagic ecosystems is also poorly understood. Observational studies have indicated that fish abundance is greater in the waters surrounding coldwater coral reefs compared to nearby waters over barren seafloor, implying enhanced productivity in the cold-water coral ecosystems. Support for this hypothesis is tested in this study using a customised Ecopath with Ecosim model. The model is applied to Childs Bank, a region on the west coast of South Africa located in the southern Benguela eastern boundary ecosystem. A previously constructed Ecopath model of the southern Benguela was modified to represent the main groups of organisms found on Childs Bank and additional groups were added to better represent the main groups associated with cold-water coral. In total, including the additional compartments, the model ecosystem consisted of 34 living compartments and three non-living compartments. Three novel living compartments were considered in the model: Cold-water corals, Sponges and Tube-worms. Two additional non-living compartments comprised Coral skeleton and Coral mucus. The Ecopath model was balanced by assuming that the three additional living groups had the same production to biomass ratios as the Macrobenthos group. The production to consumption ratio of Sponges and Cold-water corals were sourced from literature. An unconstrained non-linear minimisation function was used to solve for the biomass of the Sponge and Cold-water coral groups as their production was needed for the Ecopath model to balance; thus a biomass estimate was required for both these groups. The balanced Ecopath model was used in an Ecosim model, which was applied to three scenarios designed to investigate whether trophic links in the cold-water coral ecosystems could account for increased fish abundance: scenario 1, the removal of both cold-water coral and cold-water coral skeleton; scenario 2, changes in fishing pressure on small pelagic fish; scenario 3, the removal of coldwater coral skeleton without damage to the living coral. Scenario 3 is an artificial scenario designed to isolate the effects of cold-water coral skeleton loss from the trophic interactions from the living cold-water corals. None of the scenarios produced results with notable changes in biomasses of groups in the wider ecosystem. It is thus hypothesised that enhanced fish production results from cold-water corals changing the local oceanographic conditions through their physical structure rather than primarily by their trophic interactions.

Mestrado em Ecologia Aplicada
O crescimento da população humana tem levado a alterações globais pela transformação de habitats naturais em explorações agrícolas, florestais e áreas urbanizadas. V arias espécies, nomeadamente Carnívoros, encontraram uma forma de se adaptarem a zonas urbanas. Com este estudo pretendemos perceber se os habitats antropogénicos podem ser ameaças ou oportunidades para duas espécies de carnívoros, raposa vermelha (Vulpes vulpes) e gineta comum (Genetta genetta). Para tal, foram recolhidos dados de fatores ambientais dentro de duas áreas circulares de diâmetros fixos, correspondendo á área vital mínima e média de cada espécie e divididos em quatro hipóteses. A influência das variáveis ambientais sobre as duas espécies de carnívoros foi avaliada com base nos dados de abundância relativa e presenç - ausência de raposa e gineta. Os carnívoros foram amostrados com armadilhagem fotográfica. Os resultados mostram que o modelo de perturbação o que melhor explica os padrões de abundância das raposas, e que o modelo híbrido melhor explica a abundância relativa das ginetas. Foram também incluídas variáveis temporais para testar os padrões de atividade das espécies. A nossa hipótese de que a disponibilidade de recursos iria afetar positivamente as espécies foi refutada por não termos considerados os hábitos generalistas destas espécies. A nossa previsão de que zonas de eucalipto e folhosas iriam oferecer refúgio foi contrariada pela escolha de zonas urbanas pela raposa, possivelmente relacionada com a disponibilidade de refúgio e alimento, e a escolha de zonas próximas a eucalipto pela gineta, o que pode ser um falso positivo uma vez que pelo seu comportamento arborícola podem não ser tão facilmente registadas em locais com maior complexidade vegetal. Nós esperávamos que as variáveis antropogénicas tivessem um influência negativa na abundância relativa das espécies. No entanto, os nossos resultados mostram uma associação da raposa a zonas urbanas. A gineta está menos ativa durante o pôr do sol quando há maior atividade humana. A altitude teve um efeito significativo na abundância e presença de ginetas, talvez por estes animais estarem a usar vales, associados a cursos de água. No geral, a raposa parece ser menos afetada por habitats antropogénicos do que a gineta, provavelmente devido a sua capacidade de adaptação. Os habitats antropogénicos podem funcionar como ameaças mas podem ser melhorados para minimizar o seu efeito na vida selvagem e tornarem-se oportunidades. A amostragem de vida selvagem deve ser feita regularmente para a correta implementação de medidas de mitigação, que podem passar por passagens superiores e inferiores nas rodovias, reconfiguração da oresta e educação ambiental.
Human population growth is leading to global changes as natural habitat is transformed into farmlands, industrial forestry stands and urban areas with a negative impact on biodiversity. Several species, including carnivores, found a way to adapt to urban areas. This study aims to understand if anthropogenic habitat are threats or opportunities for two carnivore species: red foxes (Vulpes vulpes) and common genet (Genetta genetta). Data on environmental factor was collected within the average and minimum core area bu er of each species and pertaining to four hypothesis. The in uence of these environmental drivers on the two carnivore species was evaluated using the relative abundance and presence-absence data of red foxes and genets. Carnivores were sampled using camera-trap. Our results show that within both bu ers, the best model in the disturbance category best explains the relative abundance patterns of red foxes, while the the hybrid model (which comprises all best models of all categories) best explained the relative abundance of genets. A category including temporal variables was added to test species activity patterns. This category explained more of the deviance to the null model than spatial variables. We hypothesised that resources availability would have a positive e ect on species but failed to consider red foxes' and genets' generalists feeding behaviour. We predicted that both eucalyptus and broadleaf tree areas would provide refuge for both species. However,red foxes seem to explore urban areas, which can o er food, as genets chose eucalyptus areas as refuge. The latter can be a misleading results as the arboreal behaviour of this species can in uence records. We expected that anthropogenic variables would negatively in uence species' relative abundance and presence. Genets are less active during higher human activity periods, showing higher activity around dawn than around dusk, during most of the year. Altitude had a signi cant e ect on genets' relative abundance and presence. Perhaps because these animals are using river valleys. In general, red foxes seem to be less a ect by anthropogenic habitats then genets, probably because of this species high adaptability. Anthropogenic habitats can work as both threats and opportunities but can be improved in order to minimize its e ect on wildlife. Wildlife surveys should happen frequently in order to implement mitigation measures, such as under or over road passages, forest recon guration and environmental education. With these and other policies, habitats can become opportunities for wildlife.

A push for a more evidence based approach to management has resulted in the need for robust evidence of fisheries impacts (or lack thereof), including further research into fine-scale impacts of potting for which little evidence is available. The present work focusses on the inshore pot fishery in Northumberland, UK. Potting effort distribution maps - a combination of fishing vessel sightings recorded during routine patrols and fishing effort by the Northumberland Inshore Fisheries and Conservation Authority (NIFCA) – showed changes in potting effort across large sections of the study area between years (2004 – 2014). Temporal changes in fishers’ habitat selection were investigated using recently collected habitat data. Space-time clustering suggested fishers were actively targeting habitats of interest. Compositional analysis of habitat, showed that fishers preferred rocky habitats over sediment habitats when using both EUNIS level 3 and 6 habitat maps. Information on habitat use and fishing pressure provided the basis for investigation of long-term impacts of parlour potting on epibenthos and habitat within the Berwickshire & North Northumberland Coast European Marine Site (BNNC EMS) through analysis of historical videographic monitoring data between 2002 – 2011. Analysis of biotope change between years (a method recommended for monitoring purposes) showed that at the scales investigated here, change had not occurred. Weaknesses of this analysis for the use in robust ecological research are discussed. A more detailed analysis of community composition and diversity change between years showed that there was little evidence of change. However, changes in species composition and richness of ‘Faunal and algal crusts on exposed to moderately wave-exposed circalittoral rock’ were observed between years, in most models and between fishing pressures. Finally, quantification of direct impacts through in-situ experimental fishing was investigated using a BACI design. The high experimental fishing intensity, in small experimental areas, coupled with high levels of sampling and replication, provided iii robust evidence that current levels of potting are unlikely to have a direct physical impact on epibenthos in Faunal and algal crust, and Laminaria spp dominated habitats in Northumberland.

La biodiversità marina regola il funzionamento ecosistemico, responsabile della produzione di beni e servizi importanti per la biosfera ed il benessere umano. I cambiamenti climatici globali e le attività umane stanno alterando la biodiversità degli oceani ed il funzionamento ecosistemico. Al momento, partendo dalla consapevolezza che le sole misure di conservazione non sono sufficienti a invertire la degradazione degli ecosistemi, è riconosciuto che il restauro ambientale è una azione di cruciale importanza per far fronte a questa minaccia. Tuttavia, è necessaria una maggiore conoscenza scientifica per rendere efficaci azioni di restauro, specialmente negli ambienti profondi che sono largamente sconosciuti. Tra le maggiori attività che avranno impatti sugli habitat marini vi sono lo sfruttamento di risorse minerarie e la pesca a strascico, le quali, risospendendo particelle polimetalliche e sedimenti, avranno effetti principalmente sulle specie bentoniche. In questa tesi, il Corallium rubrum, specie strutturante di elevata valenza ecologica, è stato esposto a questi due tipi di particolato. Dopo la rimozione della fonte di impatto, questo organismo è in grado di recuperare parzialmente tassi di alimentazione e la sua integrità tissutale. Questo esperimento fornisce utili informazioni non solo per meglio comprendere gli effetti di tali attività su organismi bentonici, ma anche per definire possibili misure di mitigazione attraverso una modulazione appropriata della loro intensità e durata. Allevare in acquario specie di corallo minacciate potrà essere utile per futuri progetti di restauro che prevedono il trapianto di colonie donatrici. Una dieta appropriata da somministrare durante l’allevamento può avere effetti benefici sulla loro crescita ed il loro successo riproduttivo. In questa tesi, è stata studiata la selezione di cibo da parte di alcuni coralli profondi (Desmophyllum pertusum, Madrepora oculata and Dendrophyllia cornigera), i quali hanno mostrato una preferenza per il crostaceo Mysis relicta. I risultati ottenuti dalle analisi condotte sugli isotopi stabili hanno inoltre fornito nuove informazioni sulle nicchie trofiche occupate nel Mar Mediterraneo da queste specie. Una volta ampliate le conoscenze sugli habitat e le specie da restaurare, è necessario valutare l’efficacia delle procedure di rispristino che si vogliono applicare. In questa tesi, sono stati studiati gli effetti di due esperimenti pilota di trapianto della fanerogama Cymodocea nodosa e della gorgonia Eunicella singularis su attributi di funzionamento ecosistemico. I risultati ottenuti indicano che il trapianto di tali organismi, se opportunamente pianificato, non solo garantisce la loro sopravvivenza, ma può anche avere effetti positivi su processi ecosistemici chiave. Tuttavia, sono necessari ulteriori studi per valutare la possibile estensione di queste azioni per affrontare l'attuale scala spaziale di perdita di specie/habitat. Questo lavoro fornisce nuovi elementi per la comprensione dei potenziali benefici ecologici derivanti dal restauro ambientale e delle sue ricadute per la conservazione del capitale naturale.
Marine biodiversity regulates ecosystem functions, which are responsible for the production of goods and services for the biosphere and human well-being. Global changes and human activities are altering ocean biodiversity and ecosystem functioning. At present, stemming from the awareness that conservation and management are often not enough to halt and revert the degradation of threatened ecosystems, it has been recognized that active restoration is crucial to cope with this issue. More knowledge is needed to make restoration actions effective, especially for the largely unknown deep ocean. Two of the main activities that will alter marine habitats are ore exploitation and bottom trawling that, resuspending polymetallic and sediment particles, will affect benthic species. In this thesis, the habitat-forming species Corallium rubrum was exposed to these types of particles. After the removal of the disturbance, its feeding rates and tissue integrity partially recovered. This experiment provides new insights on the consequences of these activities as well as on potential mitigation strategies by properly modulating their intensity and duration. Rearing endangered corals in aquaria can be useful for future projects that aim to restore degraded reefs by transplanting healthy colonies. An appropriate diet may positively impinge on their growth or reproduction success. In this perspective, I studied the food selection of cold-water corals (Desmophyllum pertusum, Madrepora oculata and Dendrophyllia cornigera) was studied and these species showed a preference for the crustacean Mysis relicta. Stable isotope analyses provided also novel information on the trophic niches occupied by these coral species in the Mediterranean Sea. After expanding the knowledge on the habitat or the species to be restored, it is necessary to evaluate the effectiveness of the restoration actions that it might be applied. In this thesis, the effects of two pilot transplantation experiments of the seagrass Cymodocea nodosa and the gorgonian Eunicella singularis on ecosystem functioning of surrounding sediments have been studied. The results showed that transplantation can be effective and that it can have also positive effects on key-ecological processes. However, further studies are needed to assess the potential of scaling-up these actions addressing the present scale of species/habitat loss. This work provides new elements for a better understanding of the potential ecological benefits that can contribute to the conservation of the natural capital.

Nos connaissances sur les temps protohistoriques au maroc ont nettement evolue. Jusqu'a recemment, on niait purement et simplement l'usage des metaux par les paleoberberes avant l'arrivee des commercants pheniciens. Les donnees disponibles actuellement permettent d'affirmer que le maghreb occidental a connu un age du cuivre et un age du bronze. Ces deux epoques sont tres sensibles aux influences venues de la peninsule iberique. Il existe cependant des documents qui militent en faveur d'une metallurgie locale. L'age du fer au maroc est caracterise par l'essor des habitats de hauteur a caractere defensif et par la multiplication et la diversification des monuments funeraires. Ceux-ci tiennent leur prototype soit de la peninsule iberique soit du sahara. Mais il existe egalement des types de monuments propres au maroc. En l'absence de mobilier caracteristique, ces divers monuments se refusent, pour la plupart, a toute tentative de datation
Our knowledge about protohistoric times in morocco has greatly evolved. Until lately, the scientific community has always denied simply and purely, the use of metals by paleoberber populations before the arrival of the phoenician traders. The data available today allow us to say that the western maghreb knew a cooper age and a bronze age. The two ages are very sensitive to the influences coming from the iberic peninsula. However, documents in favour of a local metallurgical industry exist. The iron age in morocco is characterized by the development of the high habitat with a defensive aspect and the multiplication and the diversification of funerary monuments. These funerary monuments get their prototype either from the iberic peninsula or from the sahara. But there exist also some types of monuments which are characteristic of morocco. Since characteristic documents are not yet found, it is difficult to put a date on the majority of these monuments

Nesta dissertação investigamos o papel dos mamíferos em cascatas tróficas nas florestas tropicais, e os efeitos da configuração espacial e qualidade do habitat assim como das atividades humanas atuais sobre a distribuição de mamíferos de maior porte em uma paisagem rural de Mata Atlântica. No primeiro capítulo, através de uma revisão da literatura sumarizamos e avaliamos a evidência empírica de que mamíferos estão envolvidos em cascatas tróficas em florestas tropicais com o objetivo de indicar os avanços, os problemas e os desafios nessa área. Poucos estudos empíricos e conceituais foram encontrados na literatura, todos realizados nas últimas três décadas, enquanto que a maioria dos estudos empíricos foi realizada nos Neotrópicos. Grande parte das hipóteses relacionadas a cascatas tróficas foi apenas proposta, e considera o homem como predador de topo. Além da maior parte das variáveis quantificadas não serem adequadas para demonstrar efeitos em cascata, a escala temporal da maioria dos estudos revisados foi curta para acessar estes efeitos sobre a comunidade de plantas que contém espécies longevas. Nenhuma hipótese abordou o efeito dos predadores de topo sobre as populações de presas pequenas via o controle da densidade e distribuição de mesopredadores. A maioria das hipóteses que encontramos na literatura se refere a outros efeitos indiretos causados por mamíferos, em particular através da dispersão de sementes e da disponibilização de nutrientes via fezes. Dessa maneira, demonstramos que o termo \"cascata trófica\" tem sido utilizado amplamente, englobando outros efeitos indiretos que se propagam via outras interações que não tróficas, e que a evidência empírica disponível até o momento de que mamíferos desencadeiam cascatas tróficas em florestas tropicais é pequena. No segundo capítulo, através da amostragem de 23 remanescentes florestais e do uso de modelos de ocupação e da abordagem de seleção de modelos, investigamos como fatores associados à configuração espacial e qualidade do habitat e a outras atividades humanas em andamento interagem e condicionam a distribuição de mamíferos terrestres de maior porte em paisagens intensamente modificadas pelo homem. A assembléia de mamíferos de maior porte encontrada na paisagem estudada é simplificada e dominada por mamíferos silvestres generalistas de médio porte, sugerindo que o controle de mesopredadores e a regeneração das florestas podem estar comprometidos. Os resultados também sugerem que: (1) a distribuição de mamíferos de maior porte deve ser condicionada mais por fatores associados à configuração espacial do que à qualidade do habitat florestal; (2) as atividades humanas atuais são tão ou mais importantes que a configuração espacial e a qualidade do habitat para a maioria das espécies. O tamanho dos fragmentos e a distância a rodovias, entre os fatores associados à configuração espacial, e a caça e a presença do cachorro doméstico, entre as atividades humanas atuais, foram particularmente importantes para a distribuição das espécies de mamíferos de maior porte. A relevância das atividades humanas em andamento sugere que estratégias de manejo que foquem em mudanças na atitude da população humana, através de programas de conscientização e educação, podem ter resultados significativos em termos da persistência de populações de mamíferos em paisagens rurais.
In this dissertation we investigated the role of large mammals in trophic cascades in tropical forests, and the effects of habitat configuration and quality as well as of current human activities on the distribution of large mammals in a rural Atlantic forest landscape. In the first chapter, through a literature review we summarized and evaluated the empirical evidence that mammals are involved in trophic cascades in tropical forest, with the aim of highlighting the progress, problems and challenges in this area. Few conceptual and empirical studies were found in the literature, all of which were performed in the last three decades, while most of the empirical studies were developed in the Neotropics. Most of the hypotheses related to trophic cascades were only proposed and not tested, and considered humans as top predators. Not only most of the quantified variables were not appropriate to demonstrate cascading effects, but also the temporal scale of most studies was short to detect these effects on plant communities composed of long-lived species. We did not find hypotheses addressing the effect of top predators on the populations of small prey through the control of mesopredator density and distribution. Most hypotheses in the reviewed literature refer to other indirect effects played by mammals, especially through seed dispersal and nutrient allocation via feaces. Thus, we demonstrate that the term \"trophic cascade\" has been used widely, encompassing other indirect effects that propagate through other, non-throphic interactions, and that the empirical evidence available so far that mammals are drivers of trophic cascades in tropical forest is weak. In the second chapter, through the sampling of 23 forest fragments and using occupancy models and a model selection approach, we investigated how factors associated with habitat configuration and quality and with other current human activities interact to define the distribution of terrestrial large mammals in human-modified landscapes. The large mammal assemblage from the studied landscape is impoverished and dominated by medium-sized generalist species, suggesting that both the control of mesopredators and forest regeneration may be compromised. Our results also suggest that: (1) the distribution of large mammals is determined mainly by aspects of habitat configuration rather than by aspects of habitat quality, and (2) current human activities are equally or more important than habitat configuration and quality for most of the species. Fragment size and distance to roads, among the factors associated with habitat configuration, and hunting pressure and domestic dog presence, among those associated with current human activities, were particularly important to the distribution of large mammal species. The relevance of current human activities suggests that management strategies that focus on changing people attitudes, through programs of education, can have significant results in terms of the persistence of mammal populations in rural landscapes.

Bobtail lizards, Tiliqua rugosa, have been studied extensively in South Australia, with the majority of studies focusing on the population near Mt Mary. There is a substantial lack of literature from other localities, including Perth, Western Australia, as well as on the impact urbanization is having on this species. This study aimed to gain an insight on the spatial ecology and habitat use of bobtails local to the Perth region. Lizards held small home ranges (mean 1.4ha) that did not differ between urban and peri-urban locations. There was no significant correlation between home range size and remnant bushland patch size nor were there any associations between home range and lizard morphometrics. Home range did overlap between individuals inhabiting the same reserve. Several lizards were preferentially selecting microhabitat composition at locations where they were observed inactive and using these habitat as a refuge. However there was not one particular variable that was responsible for this significant difference but cover at several levels; namely leaf litter, canopy, low shrub, and grass trees were important. This represents their flexibility in utilizing a range of different microhabitat structures, both for refuge and when active. The bobtail lizards were recorded reaching their optimum body temperature between 12pm to 3pm for most of the year regardless of the season. Flexibility in microhabitat use as well as their ability to maintain small home ranges while rarely moving beyond the bushland patch boundary is likely why they are adapted to urban living. Due to their flexibility and ability to maintain their home range within small reserves it is important to ensure a variety of vegetation and habitat structures are available for the lizards to seek shelter under. Given that the lizards were rarely moving outside of their reserve boundaries, in order to prevent them crossing roads and potentially getting struck by cars, leaving a border around the edge of the reserve with no vegetation to encourage them to stay with the sheltered reserve.

The diet and feeding habits of the southern stingray, Dasyatis americana, were investigated through aerial surveys, land-based observations, and quantitative analysis of stomach contents. The field research was conducted in the Exuma Cays Land and Sea Park, central Bahamas. Systematic aerial surveys and the land-based observations were made to determine population density and feeding periodicity in terms of time or tidal phase. In August, 1989, systematic surveys were flown over two cays in the Park; a 12 km2 area around Waderick Wells Cay and a 21km2 area around Shroud Cay. Both survey areas were flown three times over different times of the day. Over the large area covered by the aerial surveys the population varied over time of day. A significantly higher density occurred in the morning for both grids and was lowest in the afternoon for both grids suggesting that the stingrays prefer to feed early in the day in the summer. The peak density was 2.07 stingrays per km2 for the Waderick Wells survey area and 1.87 per km2 for the Shroud survey area. A total of 117 hours of land-based observations were made over 4 months; with 28 to 31 hours of observations in April and May 1990 and January and July, 1991. The land-based observations indicated that the stingrays were actively feeding throughout the day, but showed some increase in feeding activity during the high tidal phase. The habitat utilization was recorded during the land-based observations and showed that the stingrays spent most of their time feeding in the soft sediment habitats, thus taking advantage of the soft sediment algal turf and sandy shoal habitats that dominate the shallow marine environments within the Park. Eighteen stingrays were collected in January, 1991 for stomach content analysis. Decapod crustaceans were the most important prey category, but the large number of prey types found in all of the stomachs indicates that the southern stingray is a generalist feeder. There were no empty stomachs and 77% of the stomachs had more than 20 prey items. Stomach fullness measures did not indicate any feeding periodicity. The southern stingray is a generalist feeder taking advantage of a broad range of prey types and opportunistic in its feeding habits, showing no strong feeding periodicity.

Coastal infrastructure has replaced many vital fish nursery habitats with structures designed without fully mitigating for the loss of the natural ecosystems. This thesis details research focused on the use of small, inexpensive, artificial reef modules as replacement juvenile fish habitat within marinas. My research hypothesis was that the placement of small, structurally complex artificial reef modules would increase fish abundance and species richness relative to unmodified marina seawalls. Non-destructive visual surveys of fishes were completed monthly for 14 months for 12 artificial reef sites and 12 control (unmodified) sites within the Nova Southeastern University Guy Harvey Oceanographic Center (NSU-GHOC) marina. Divers recorded species, abundance, and size class (0-2 cm, >2-5 cm, >5-10 cm, >10-20 cm, >20-30 cm, >30-50 cm, >50 cm) for all sites. Data was statistically analyzed using analysis of variance (ANOVA) and post-hoc Student Newman-Keuls (SNK) tests to explore differences in mean abundance, mean species richness, and mean abundance and species richness by size class and month. Total mean fish abundance and mean species richness (all months and sizes combined) were both significantly higher at artificial reef sites than at control sites. Artificial reef sites were consistently higher in total abundance and species richness when analyzed by month. Analysis of mean abundance by size class found the >2-5 cm, >5-10 cm, >10-20 cm and >20-30 cm classes were significantly higher for artificial reef sites. Species richness analysis by size class found classes >2-5 cm, >5-10 cm, >10-20 cm, and >20-30 cm were significantly higher at artificial reef sites. Fishes from the grunt (Haemulidae) and snapper (Lutjanidae) families contributed the most to the total abundance for both types of sites. These results support my hypothesis and have important implications for mitigating ecological impact to coastal fish nursery areas with the use of artificial structure.

The world-wide intensification of agriculture has led to a decline in species richness due to land use change, isolation, and fragmentation of natural and semi-natural habitats in agricultural and forestry landscapes. As a consequence, there is a current landscape management focus on the importance of green infrastructure to mitigate biodiversity decline and preserve ecosystem functions e.g. pollination services and pest control. Even though intensification in agriculture has been ongoing for several hundreds of years, remnant habitats from earlier management practices may still be remaining with a surprisingly high plant richness. Preserving these habitats could help conserving plant species richness in agricultural landscapes, as well as other organisms that are dependent on plants for food and shelter. In this thesis I focus on two small remnant habitats; midfield islets and borders between managed forest and crop field in southeastern Sweden. In the past, both habitats were included in the grazing system and therefore often still have remnant population of grassland specialist species left today. I have used these two remnant habitats as model habitats to investigate the effect of landscape factors and local factors on species richness of plants, flower morphologies and plants with fleshy fruits. Additively, I analysed the effect of surrounding landscape and local openness on the functions; pollination success, biological pest control of aphids and seed predation on midfield islets. One of my studies showed that spatial distribution and size of the habitat affected plant species richness. Larger habitat size and higher connectivity between habitats increased species richness of plants in the habitats. Openness of the habitats was shown to be an important factor to increase species richness and richness of flower morphologies, both on midfield islets and in forest borders. Even though midfield islets had the highest species and morphology richness, both habitat types are needed for habitat complementary as forest borders have more plants with fleshy fruits and a higher richness of plant species that flowers in spring/early summer. It was also shown that a more complex forest border, not just with gaps in the canopy, but also with high variation in tree stem sizes increases plant species richness in the field layer. The conclusion is that by managing small remnant habitats to remain or become more semi-open and complex in their structure, would increase species richness of plants, grassland specialist species, and flower morphologies. It would also increase some ecosystem functions as seed predation and biologic pest control of aphids are more effective close to trees. If both midfield islets and forest borders would be managed to be semi-open, the area and connectivity of semi-open habitat would increase in the agricultural landscape, which may also improve pollination success as the connectivity between populations has a possibility to increase. Grassland specialist species are clearly abundant in the small remnant habitats. As the decline of semi-natural grasslands is causing a decline in grassland specialists’ species, not only plants, I recommend that small remnant habitats are included in conservation and management plans and strategies to improve habitat availability and connectivity for grassland species in agricultural landscapes.

Research funder Ekoklim. Project:4339602.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.

This research demonstrates the utility of repeat acoustic and photographic surveys for monitoring biotopes and hard-substratum communities in temperate waters. Kappa analysis of results derived from time-lapse backscatter surveys conducted at Church Bay, Rathlin Island (1999,2008 and 2009) indicate that the spatial distribution of biotopes is highly similar between each biotope map, possibly due to the stability of bedforms shaped by the local tidal regime. Maximum change is represented by seasonal and annual changes in the growth of Zostera marina. Changes induced by kelp harvesting are not detected in backscatter data. Low-cost photo-mosaics derived from stills and video imagery of fixed quadrats (1 OO-x-l 00 cm) are compared. Although video-collection is quicker, more species and less-conspicuous taxa are identified from stills imagery. Data extraction using point-intercepts proves efficient and generates data sensitive to 10% community change (N=16), but detects fewer species than the visual estimation measure. Frequency-of-occurrence extraction measures significantly over-estimate benthic cover. Seasonal growth, recruitment and mortality of Caryophyllia smithii, Hymeniacidon perleve and Plocamium cartilagineum are estimated to nearest 0.04 ern? month-l using digitisation. The presence of algal canopies reduce the accuracy of sessile-invertebrate cover estimates in spring and summer. Exploratory analysis of results from photoquadrat surveys conducted at Damicornis Bay, Rathlin Island (2009 and 2010), identifies six distinct sub-communities on a boulder slope. Community variability obscures detection of change. However, analysis of the most dominant sub-community indicates that boulder-slope community shifted, possibly due to local erosion of sediment. Optimal balance between precision, efficiency and species-detection ability for photoquadrats (25-x-25 cm) is 50 points-per-image. Functional groups retain structural relevance of communities, while improving precision, sensitivity and efficiency of data extraction and community-representation measures relative to full-species compositions. Continued monitoring of hard-substratum communities using high-resolution photoquadrats and fixed-photomosaics is recommended.

The abundance and diversity of moths and their larvae are compared in various woodland habitats within Bernwood Forest in lowland England to assess the impact of large-scale planting of introduced conifers and of conservation measures including coppicing and ride-side management. Light trap catches of moths in conifer plantations and in a recently coppiced site contained significantly fewer individuals and fewer species over the year compared with sites in adjacent overgrown coppice, but species diversity, measured by Fisher's index 0<. , was higher because cat ches in the latter were dominated by some very abundant species. Only 14 of the 431 species of macro-moths recorded from Bernwood Forest have larvae which feed on conifers but 138 species were found breeding on native weed species in the conifer plantations. Densities of larvae on individual native shrubs in conifer plantations were not significantly different from those in broadleaved stands. Mark and recapture of adult moths demonstrated considerable movement between habitats. More moths of more species were caught in rides than in adj acent woodland stands using Robinson traps. Heath traps in rides frequently did not catch more species or more moths than within woodland stands. Catches in Heath traps were generally largest in overgrown coppice. Catches at all sites were related to the abundance of larval host-plants but were also influenced by the distance over which the trap was visible and the amount of canopy shade. Three methods of cornpensat ing for differences in shade between trap-sites are explored. Heath traps at ride intersects captured on average 55% of the species at a Robinson trap per night; in woodland stands catches averaged 68% of the species. At least thirteen nationally rare species have disappeared from Bernwood since timber clearance prior to conifer planting. The implications for biological survey work and for nature conservation are discussed,