Please read the abstract before the references of this document. / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted

Surrounded by the ocean, Taiwan is geographically positioned along the rim of the continental shelf and Deep Ocean. Owing to the terrain distribution and geological characteristics of this island, the coastline possesses abundant sand dune resources, which is considered priceless not only as the last natural defense system of the coast but also for the functions it performs in various aspects including tourism attractions, academic contributions, and biological environment. Since the scarcity of ground in Taiwan, high demand of land usage often endangers coastal dunes. Consequently, coastal dunes are facing serious issues regarding rubbish dumping, wastewater accumulation, manmade misuse, development of industrial estate, and barrier flat exploitation. Currently, Taiwanese government has not yet established an ordinance; neither have we advanced policy of coastal dunes protections, nor have we adopted the Seashore Pact. Barely a few enactments scattered in assorted pacts. The argument in this research is primarily centering on Taiwanese coastal dunes, ranging from the functions and values of sand dunes resources to international trends of sand dunes reservations. Furthermore, the purpose of this study is to deliberate real conditions and contemporary management mishaps of coastal dunes in Taiwan, in order to further strategize the sustainability and managerial implications.

This dissertation presents the results of a multi-year interdisciplinary study of a dynamic coastal dune ecosystem restoration effort in Pacific Rim National Park Reserve in British Columbia, Canada. The research is the result of a collaboration with Parks Canada Agency (PCA) who, under the Species at Risk Act (SARA), are mandated to restore habitat for SARA listed species within the dune complex. In response, PCA committed to, and implemented, a dynamic dune ecosystem restoration program that involved widespread removal of invasive vegetation (Ammophila spp.), transplanting of native vegetation, introduction of an endangered species, and volunteer programs to prevent re-growth of Ammophila. A comprehensive monitoring program was developed with PCA and undertaken by the author and PCA collaborators from start of the project in Summer 2008 to Fall of 2012. This dissertation is the product of independent research by the author carried out under the supervision of the advisory committee and does not reproduce written materials prepared for, or by, PCA. The dissertation consists of three separate journal manuscripts (the first two published by completion of the dissertation) that stand alone as independent investigations but are structured here to provide a natural progression of research findings and allow for an overall synthesis of ideas and broader contributions of the research. The dune restoration program afforded an opportunity to review restoration trends and methods and implement a strategy and monitoring protocols based on leading edge science. Accordingly, the first manuscript, Chapter 2, summarises recent trends in coastal dune restoration, discusses relevant research surrounding beach-dune morphodynamics and coastal dune activity, and reviews preliminary data from the project. The study identifies usable control data for the project and builds the criteria for assessing the project as a whole. The second manuscript, Chapter 3, presents and analyses the core data obtained for the dissertation - 5 years of geomorphic monitoring from detailed land surveys with 3 years of analysis of beach-foredune-transgressive dune sediment budget responses derived from aerial LiDAR surveys. This chapter identifies several trends in the dune systems’ response to restoration that, with reference to the indicators developed in Chapter 2, suggest improved levels of dynamism in the landscape. Finally, Chapter 4 (manuscript 3), extends the findings of the restoration study and utilises the rich data set obtained from the restoration program to develop a dynamic mapping technique that better conveys the spatial-temporal morphodynamic behaviour of dune ecosystems. The study comments broadly on the potential to apply these data and techniques to the study of disturbance events in beach-dune systems. The dissertation is concluded (Chapter 5) with an overall summary of key research objectives and contributions, and presents recommendations for future research. / Graduate

Ecological restoration that aims to reinstate indigenous processes may be constrained by regional and local conditions, especially those that drive dispersal and colonisation. Local conditions can be managed, while regional conditions cannot. The management of costly rehabilitation programmes is considered best practice when scientifically informed. My thesis documents the responses of biological communities to a range of local conditions developing in coastal dune habitats in response to ecological restoration. Here, landscape-level (spatial structure of patches of tree canopies) local conditions were distinguished from site-level (topography, soil nutrient content, woody plant community richness, microclimatic variables) local conditions. The spatial structure of tree canopies varied over time and differed between the mining lease site and the relatively undisturbed benchmark site prior to (1937- 1970), and after (1990-2006) mining. For example, approximately 20% of the mining lease site and 40% of the benchmark site was covered by tree canopies prior to mining. However, after mining and rehabilitation, the structure of tree canopies began to converge towards that of the benchmark. The topographic profile of coastal dunes was less heterogeneous after mining and rehabilitation than before. Aspect, elevation and gradient of dune slopes were also different and had shifted in space. Variability in the structure of tree canopies could not explain variability in species richness, forest-associated species richness and proportion of benchmark species for the millipede, dung beetle and bird communities ashad been expected. However, species composition did change (though idiosyncratically) with age-related changes in soil nutrient availability and tree species diversity. Temperature, relative humidity and light intensity varied with dune topography, but soil nutrient content (C: N ratio and pH) was better accounted for by the age of the regenerating forest than by dune topography. Similarly, analysis of covariance suggested that tree canopy density, woody plant richness and millipede species richness only responded to the aspect, elevation and gradient of restored coastal dunes when age was taken into account as a covariate. However, the response of keeled millipedes to dune topography, regardless of regeneration age, suggested that the microclimatic variability brought about by topographic heterogeneity may provide these specialists with suitable microhabitats. Throughout my thesis, the age of regenerating patches of indigenous canopies was often more important as an explanatory variable than habitat conditions per se. Age itself is not a determinant of biological communities, but merely the axis along which habitat conditions change with succession, and later, patch dynamics. Therefore, as elsewhere, my thesis has highlighted age as a useful proxy for the response of biological communities to local conditions. It seems that managing local variables such as those considered in my assessment is not an avenue through which to enhance restoration. After kick-starting initial conditions, best practice rehabilitation management should therefore focus on minimizing external disturbances rather than interfering with natural processes. / Thesis (PhD)--University of Pretoria, 2013. / Zoology and Entomology / unrestricted

Foredunes are formed and developed in association with vegetation. A bare sand area has been viewed as a measure of dune mobility or activity and researched in association with climate controls: particularly wind power, annual mean precipitation, and temperature, expressed in annual mean potential evapotranspiration. There has been no research that utilized the patterns of bare sand areas to classify foredune areas in coastal dune systems and investigated climate controls related to sand patch patterns, or “foredune textures” such as size, number, and distribution of sand patches Four foredune types were classified based on four landscape metrics (PLAND: percentage of bare sand area, PLADJ: proportion of like-adjacencies, NLSI: normalized landscape shape index, and ENN_RA: range of Euclidean nearest neighbor), by applying the concepts and methodologies of landscape ecology. Four climate variables (annual mean precipitation, annual mean potential evapotranspiration, Lancaster’s mobility index, and the standard deviation of annual mean precipitation) were found to affect the foredune types and help in distinguishing one foredune type from another. The amount of bare sand area on coastal foredune areas can be explained by annual mean precipitation (R^2 is 0.52 at the 99 % confidence level), standard deviation of precipitation (R^2 is 0.51 at the 99 % confidence level), and Lancaster’s mobility index (R^2 is 0.37 at the 99 % confidence level) but wind variables such as drift potential do not explain much (R^2 is 0.04 at maximum). This suggests that dune activity or stabilization in coastal dune systems is mainly controlled by vegetation cover, which is in turn affected by precipitation. Foredune textures can be a useful tool to predict foredune types in association with future climate change, and the optimal averaging period of precipitation for each bare sand area was seven years.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The ecodynamics analysis of coastal dunes of Sergipe determined the role and the interactive effect of the anthropic action and of the natural dynamics in the occured fast ambient changes in two sample units of the Northern and Southern Coastline from Sergipe. The present research searched the detailing of the existing ambient dynamics in the fields of the dunes of Pirambu (Northern portion) and Estância (Southern portion) by means of the structural and functional aspects with prominence to the conditioning expressive of dunar vulnerability. The knowledge of the conditions of balance of the systems of the dunes based on the Tricart s Ecodynamics principle demanded the deepening of the relations between geomorphological, fitogeographics, climatological and anthropical the components of the systems of dunes. The use of this integrator perspective found for the Northern Coastline (Biolological Reserve of Santa Isabel) a scenery with dune stability predominance explained by the low threat of system degradation, lack of obstacles to the transgression of the frontal dunes and low human interference. However, the current situation of stable environment may suffer anthropogenic derivations generating a growing tendency to ecodynamical intergrade, covering a longer cycle of environmental changes in levels of vulnerability assessed. The dunes of the Southern Coast include such features with predominance of the morphogenesis upon the pedogenesis. In terms of its ecodynamical assessment, they appear as unstable environments and environments intergrade, but with tendency to a progressive instability. Such dune situation in degradation is explained by the increasing process of disordered occupation, for the expansion of the land divisions and touristic enterprises, beyond the nonexistent of measures of protection that glimpse the containment of processes as illegally carried through dune dismountings. / A análise ecodinâmica das dunas costeiras de Sergipe partiu da verificação do papel e dos efeitos interativos da ação antrópica e da dinâmica costeira nas mudanças ambientais rápidas ocorridas em duas unidades amostrais do Litoral Norte e do Litoral Sul sergipano. A presente pesquisa buscou o detalhamento da dinâmica ambiental existente nos campos dunares de Pirambu (porção Norte) e Estância (porção Sul) mediante os aspectos estrutural e funcional com destaque aos condicionantes mais expressivos de vulnerabilidade dunar. O conhecimento das condições de equilíbrio dos sistemas dunares baseado no princípio ecodinâmico de Tricart demandou o aprofundamento das relações entre as componentes geomorfológicas, fitogeográficas, climáticas e antrópicas dos sistemas dunares. A utilização da perspectiva integradora da paisagem encontrou para o Litoral Norte (Reserva Biológica de Santa Isabel) um cenário com predominância da estabilidade dunar explicado pela pouca ameaça de degradação ao sistema, inexistência de obstáculos à transgressão das dunas frontais e baixa interferência antrópica. Todavia, a atual situação de meio estável pode sofrer derivações antropogênicas geradoras de uma crescente tendência ecodinâmica ao intergrade, abrangendo um ciclo mais longo de mudanças ambientais nos patamares de vulnerabilidade aferidos. Nas dunas do Litoral Sul predomina a morfogênese sobre a pedogênese. Em termos de sua avaliação ecodinâmica, apresentam-se como meios instáveis e meios em intergrade, mas com tendência a uma progressiva instabilidade. Tal situação de dunas em arrasamento é explicada pelo crescente processo de ocupação desordenada, pela expansão dos loteamentos e empreendimentos turísticos, além da inexistência de medidas de proteção que vislumbrem a contenção de processos como desmontes de dunas realizados ilegalmente.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The ecodynamics analysis of coastal dunes of Sergipe determined the role and the interactive effect of the anthropic action and of the natural dynamics in the occured fast ambient changes in two sample units of the Northern and Southern Coastline from Sergipe. The present research searched the detailing of the existing ambient dynamics in the fields of the dunes of Pirambu (Northern portion) and Estância (Southern portion) by means of the structural and functional aspects with prominence to the conditioning expressive of dunar vulnerability. The knowledge of the conditions of balance of the systems of the dunes based on the Tricart s Ecodynamics principle demanded the deepening of the relations between geomorphological, fitogeographics, climatological and anthropical the components of the systems of dunes. The use of this integrator perspective found for the Northern Coastline (Biolological Reserve of Santa Isabel) a scenery with dune stability predominance explained by the low threat of system degradation, lack of obstacles to the transgression of the frontal dunes and low human interference. However, the current situation of stable environment may suffer anthropogenic derivations generating a growing tendency to ecodynamical intergrade, covering a longer cycle of environmental changes in levels of vulnerability assessed. The dunes of the Southern Coast include such features with predominance of the morphogenesis upon the pedogenesis. In terms of its ecodynamical assessment, they appear as unstable environments and environments intergrade, but with tendency to a progressive instability. Such dune situation in degradation is explained by the increasing process of disordered occupation, for the expansion of the land divisions and touristic enterprises, beyond the nonexistent of measures of protection that glimpse the containment of processes as illegally carried through dune dismountings. / A análise ecodinâmica das dunas costeiras de Sergipe partiu da verificação do papel e dos efeitos interativos da ação antrópica e da dinâmica costeira nas mudanças ambientais rápidas ocorridas em duas unidades amostrais do Litoral Norte e do Litoral Sul sergipano. A presente pesquisa buscou o detalhamento da dinâmica ambiental existente nos campos dunares de Pirambu (porção Norte) e Estância (porção Sul) mediante os aspectos estrutural e funcional com destaque aos condicionantes mais expressivos de vulnerabilidade dunar. O conhecimento das condições de equilíbrio dos sistemas dunares baseado no princípio ecodinâmico de Tricart demandou o aprofundamento das relações entre as componentes geomorfológicas, fitogeográficas, climáticas e antrópicas dos sistemas dunares. A utilização da perspectiva integradora da paisagem encontrou para o Litoral Norte (Reserva Biológica de Santa Isabel) um cenário com predominância da estabilidade dunar explicado pela pouca ameaça de degradação ao sistema, inexistência de obstáculos à transgressão das dunas frontais e baixa interferência antrópica. Todavia, a atual situação de meio estável pode sofrer derivações antropogênicas geradoras de uma crescente tendência ecodinâmica ao intergrade, abrangendo um ciclo mais longo de mudanças ambientais nos patamares de vulnerabilidade aferidos. Nas dunas do Litoral Sul predomina a morfogênese sobre a pedogênese. Em termos de sua avaliação ecodinâmica, apresentam-se como meios instáveis e meios em intergrade, mas com tendência a uma progressiva instabilidade. Tal situação de dunas em arrasamento é explicada pelo crescente processo de ocupação desordenada, pela expansão dos loteamentos e empreendimentos turísticos, além da inexistência de medidas de proteção que vislumbrem a contenção de processos como desmontes de dunas realizados ilegalmente.

Premise: Invasive plant species can integrate into native plant–pollinator communities, but the underlying mechanisms are poorly understood. Competitive interactions between invasive and native plants via heterospecific pollen (HP) and differential invasive HP effects depending on HP arrival time to the stigma may mediate invasion success, but these have been little studied. Methods: We evaluated patterns and effects of HP receipt on pollen tube growth in two native and one invasive species in the field. We also used hand-pollination experiments to evaluate the effect of invasive HP pollen and its arrival time on native reproductive success. Results: Native species receive smaller and less-diverse HP loads (5–7 species) compared to invasive species (10 species). The load size of HP had a negative effect on the proportion of pollen tubes in both native species but not in the invasive, suggesting higher HP tolerance in the latter. Invasive HP arrival time differentially affected pollen tube success in native species. Conclusions: Our results highlight the need to study reciprocal HP effects between invasive and native species and the factors that determine differential responses to HP receipt to fully understand the mechanisms facilitating invasive species integration into native plant–pollinator communities.

Coastal foredunes are natural aeolian bedforms located landward of the backshore and which interact continuously with the beach. Traditionally, coastal dunes have been associated with onshore winds, however they can be found under more complex wind regimes where offshore winds are common such as the UK East coast, Northern Ireland and New Zealand. This research investigates the ways in which foredune-beach interactions occur under a complex wind regime at a range of overlapping temporal and spatial scales and is innovative in that it explicitly links small-scale processes and morphodynamic behaviour to large scale and long-term dynamics. The study area is the north Lincolnshire coast, East England. Detailed observations of airflow at three locations under varying wind regimes revealed considerable spatial variations in wind velocity and direction, however it was possible to determine a general model of how foredune topography deflected and modified airflow and the resultant geomorphological implications (i.e. erosion and deposition). During direct offshore and onshore winds, airflow remained attached and undeflected; and distinct zones of flow deceleration and acceleration could be identified. During oblique winds airflow was deflected to become more parallel to the dune crest. The field sites used are characterized by a seasonal erosion/accretion cycle and a series of increasingly complex models was developed and tested to determine whether it was possible to predict sand volume changes in the foredune-beach system based on a limited number of variables. The model predictions were tested against detailed digital terrain models at a seasonal timescale. The model prediction that best matched the observed (surveyed) sand volume changes included wind speed, direction, grain size, fetch effect controlled by beach inundation and angle of wind approach was accurate to within ±10% for 18 out of 48 tests at the seasonal scale and 6 out of 12 tests over periods of >5 years. A key variable influencing foredune-beach sand volume is the magnitude and frequency of storm surge events and this was not factored in to the model, but may explain the model-observation mismatch over the medium-term on two occasions. Over the past 120 years historical maps and aerial photographs indicate long-term foredune accretion of approximately 2 m year-1 at the three study sites (1891-2010). At this timescale, rates of coastal foredune accretion reflect the low occurrence of severe storm surges and suggest rapid post-storm recovery. The morphological response of the foredune-beach morphology is considered to be a combination of controlling and forcing factors. Process-responses within the system, associated with nearshore interactions and sediment transfer from the littoral drift, are compiled into a multi-scale morphodynamic model. Important to match appropriate dataset to scale of research question or management plan being explored. In the case of management, long-term records of past activity are necessary to predict the future but also to understand natural responses of system to short-term impact such as storm surge.

Made available in DSpace on 2015-03-05T16:20:40Z (GMT). No. of bitstreams: 0 Previous issue date: 27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As áreas úmidas são ecossistemas importantes para a conservação, devido à alta diversidade que sustentam. Os anfíbios anuros são importantes componentes das comunidades biológicas em áreas úmidas do sul do Brasil. A falta de informações a respeito da diversidade, riqueza, distribuição geográfica e ecologia de anuros é uma das principais limitações para sua conservação. Hidroperíodo e diversidade de habitats são importantes fatores que influenciam a distribuição de espécies e a estrutura das comunidades de anuros. No entanto, a real influência desses fatores sobre os anuros adultos e girinos em áreas úmidas de dunas costeiras do sul do Brasil é pouco conhecida. Este estudo teve como objetivo testar se a diversidade de habitat e o hidroperíodo influenciam na distribuição espacial e temporal de anuros em áreas úmidas costeiras do Rio Grande do Sul. Além disso, testamos se a similaridade na composição de espécies de anuros estava associada a descritores da estrutura dos habitats. Esses descritores foram área, núm / Wetlands are important ecosystems for conservation, due to the great biodiversity they support. Anuran amphibians are important components of the biological communities in southern Brazil wetlands. Lack of data is one of the main restrictions to conservation programs. In this sense, studies on diversity, species richness, geographic distribution, and ecology of anuran populations are needed. Hydroperiod and habitat diversity are important factors influencing species distribution and communities structure in anurans. However, there are no such data for adult anurans and tadpoles in wetlands of coastal dunes in southern Brazil. The aim of this study was to test whether habitat diversity and hydroperiod can be related to spatial and temporal distribution of anurans in wetlands of coastal dunes in Rio Grande do Sul. Besides, we tested whether anurans composition were associated to structural features. These features were area, numbers of drought, months of drought, anuran predator richness, floating vegetation,