3,947 research outputs found

    The Hillslope Signature of Knickpoints Resulting from Stream Capture, Coastal Processes, and Resistant Bedrock on Santa Cruz Island, CA: Insights from and Automated Knickpoint-Selection Algorithm

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    Oversteepened, convex segments of stream channels called knickpoints have been utilized as markers that commonly migrate upstream and delineate abrupt changes in erosional efficiency influenced by base-level fall, changes in rock strength, or strong spatial variations in discharge. Currently, few analyses based on DEMs enable discrimination among migrating knickpoints related to changes in external forcing (baselevel fall, stream capture, and climate) versus fixed knickpoints related to internal forcing within a catchment (resistant bedrock units, coarse debris flow run-outs at tributary junctions, or landslide dams). Furthermore, few analyses have characterized the extent that migratory knickpoints steepen downstream-adjacent hillslopes. To study these interactions, we exploit a 1-m resolution LiDAR DEM of Santa Cruz Island (SCI), CA and a new algorithm that automatically extracts and measures the dimensions of any knickpoint in a regional DEM. The algorithm reduces knickpoint selection time by >99% and removes selection bias from the traditional means of regional knickpoint identification that relies on visual inspections of individual longitudinal profiles. The spatial pattern of knickpoints located by the algorithm highlight three dominant knickpoint-forming processes on SCI: knickpoints fixed to contacts between rocks of different strength, knickpoints migrating upstream from an incision pulse caused by a significant stream capture event, and mobile knickpoints stemming from relative sea-level fall and wave erosion of sea-cliffs. Nearly 36% of the hillslope area downstream from migratory knickpoints has slopes above threshold values of 35˚, and on average, these regions display a 4-6˚ steeper median hillslope-gradient than hillslopes upstream from migratory knickpoints. Hillslope-gradient histograms are nearly identical upstream and downstream from knickpoints fixed to spatial changes in rock strength or when re-analyzing hillslopes surrounding migratory knickpoints with a 10-m resolution DEM. From regionally extensive map of stream knickpoints, geological context, and hillslope attributes extracted from a 1-m resolution DEM, new insights emerge on the controls of landscape evolution; insights that would be much harder to obtain through individual knickpoint selection or lower resolution imagery

    Effects of introduced trout predation on non-diadromous galaxiid fish populations across invaded riverscapes

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    Abstract We assessed the landscape-scale effect of predation pressure from trout on the population integrity and distributions of non-diadromous galaxiids in high-country streams of the South Island, New Zealand. The effects of trout (brown trout, Salmo trutta, and rainbow trout, Oncorhynchus mykiss) on two widespread species, the Canterbury galaxias (Galaxias vulgaris Stokell) and the alpine galaxias (G. paucispondylus Stokell) were assessed. Experiments confirmed that both species were vulnerable to trout predation and that habitat (size and disturbance regime) may be a factor in local co-occurrence. Quantitative electrofishing surveys indicated that G. paucispondylus distributions were less affected by trout than G. vulgaris distributions and that the species’ range was limited by temperature. Trout created demographic sinks for G. vulgaris across most invaded reaches, while refuge populations in streams above barriers to trout acted as demographic sources for this species. G. vulgaris was consistently absent from small, stable stream reaches far from sources, indicating that trout predation pressure and propagule pressure (driven by immigration from sources) interact to drive local G. vulgaris persistence in trout-invaded reaches. Predation pressure is likely to be highest in areas where infrequent flooding allows high densities of large trout (> 150 mm FL) to occur and where there are few refugia for galaxiids. A spatial model was developed to predict exclusion of galaxiids by trout across invaded networks. If used appropriately, the model could be used to find new refuge populations of non-diadromous galaxiids and to aid planning of active rehabilitation of trout-invaded river networks

    Migration, Unemployment and Net Benefits of Inbound Tourism in a Developing Country

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    International tourism is increasingly viewed as one of the best opportunities for a sustainable economic and social development of developing countries. There is also an increasing concern from public policy makers as to whether mass tourism coastal resorts can play a catalytic role in the overall economic development and improve the real income of their community. In this paper, we present a general equilibrium model which explicitly takes into consideration specific features of some developing countries (e.g. coastal tourism, dual labour market, unemployment, migrations, competition between agriculture and tourism for land) to analyse the ways by which an inbound tourism boom affects this kind of country, in particular its real income. We define the conditions under which an inbound tourism boom makes developing countries residents worse off.Economic impacts, General equilibrium model, Inbound tourism, Migration, Unemployment, Developing countries

    Integrated assessment of ecosystem connectivity and functioning: coastal forest avifauna of northeast Australia

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    The extraordinary diversity of species-environment relationships that occur across space and time can engender a deep curiosity of their mechanistic underpinnings. Moreover, the rapid rate of ecosystem change associated with anthropogenic and climatic pressures makes information regarding species' landscape and resource use ever more important. Without this information, we will be unable to effectively protect landscapes and their constituent species. The coastal ecosystem mosaic of northeast Australia, which is comprised of a high diversity of habitat types, provides a suitable region for investigating how species respond to heterogeneity in habitat and resource availability. The present thesis examined ecosystem functioning in heterogeneous coastal landscapes of northeast Australia for forest avifauna. An array of analytical approaches were employed to establish a comprehensive understanding: 1) spatial assessment to determine relationships between regional landscape connectivity and coastal forest bird assemblages, 2) isotopic assessment to evaluate the local foraging ecology of mangrove bird assemblages, and 3) nutrient assessment of cross-ecosystem connectivity provided by a migratory coastal forest bird species (i.e. the Pied Imperial-Pigeon (Ducula bicolor)). Within the coastal ecosystem mosaic, mangrove forests sit at the land-sea interface. Therefore, to effectively 'set the scene' I review how mangrove birds require and facilitate connectivity through their use of the broader coastal landscape. Next, to specifically assess regional landscape patterns and processes influencing northeast Australia's coastal forest avifauna, I surveyed the composition of bird assemblages in four of the major coastal forest types occurring throughout the region (i.e. Eucalypt, Melaleuca, mangrove, and rainforest). Following this, spatial patterns of habitat configuration within the coastal landscape (i.e. structural connectivity) were quantified to understand broad relationships between coastal forest bird assemblage composition and landscape heterogeneity at multiple spatial scales. Most bird species in coastal northeast Australia occurred in multiple forest types. Spatial assessment suggested that Melaleuca woodlands are a keystone structure that supports use of the entire coastal landscape mosaic by coastal forest generalist species. However, the species composition of mangrove bird assemblages was distinct relative to other coastal forest types. Therefore, to provide more detailed information regarding the response of coastal forest generalists and mangrove specialists to specific forest attributes, functionally connected forest networks were developed to assess the relative importance of forest area, availability, and connectivity to their compositional turnover. This revealed that mangrove specialists and coastal generalists differ in the forest attributes they require (i.e. area vs. availability) to maintain regional beta diversity. Understanding landscape pattern-process relationships that drive bird assemblage composition and turnover can inform the prioritization of regional-scale landscape features for protection. However, species' responses to local-scale spatiotemporal variability in resource availability may also play a role in these relationships. I used isotopic analysis to better understand the foraging ecology of coastal forest birds in a highly dynamic mangrove forest environment. This demonstrated that flexible and opportunistic foraging strategies were prevalent among coastal forest generalist species. However, specialized foraging strategies were employed by some species, primarily for resources that were uniquely available in mangrove forests (i.e. estuarine fish and crabs). Mobile species not only respond to landscape patterns and processes, but can also facilitate connectivity processes through their movement (e.g. nutrient transfer, pollination, genetic linking, etc.). To determine the implications of avian mobility for ecosystem functioning in northeast Australia, I focused on a migratory coastal forest bird species, the Pied Imperial-Pigeon (Ducula bicolor). Nutrient measurements demonstrated that Pied Imperial-Pigeons provide mainland-derived nutrient subsidies to island forests, highlighting their important role as an avian mobile-link species. The integrated analytical approach used in this thesis has provided insight to the complexity of coastal landscapes and their use by forest avifauna. This has broadened our understanding of coastal ecosystem functioning to include a hierarchy of ecosystem components that exist at local and regional scales. The ecosystem properties that emerge from interactions across coastal ecosystem components include: vegetative connectivity, compositional turnover, avian foraging strategy, and nutrient transfer. Results from this thesis can inform the holistic conservation and management strategies that are required to maintain coastal ecosystem functioning in regional northeast Australia

    Variation in the Configuration of the Middle Snake River and Its Relationship to Prehistoric Fishing Site Locations

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    The configuration of the various elements of a river system can have significant impacts on the availability, abundance, and nutritional profitability of aquatic organisms utilized as food by groups of human foragers. These factors may have influenced the location and timing of prehistoric fishing along the Middle Snake River in southern Idaho during the Late Archaic when use of fish as a resource increased (beginning approximately 1500 B.P.). Previous work has established a relationship between physiographic features of the Middle Snake River channel and the presence of fishing sites. To improve on future studies of this type, it is important to question two assumptions: 1) the category of “fishing site” is useful and defensible; and 2) the configuration of the Middle Snake River was static during the period when archaeological evidence suggests increased use of fish. This study assesses the argument that prehistoric camp locations, regardless of evidence for fishing, were influenced by physiographic features of pre-dam channels and by possible changes in features over time

    The Human Biodiversity in the Middle of the Mediterranean. Study of native and settlers populations on the Sicilian context

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    [IT] Negli ultimi 200.000 anni, la specie umana si è diffusa in tutta la Terra, adattando la sua morfologia e fisiologia a un'ampia gamma di habitat. Lo scheletro umano ha quindi registrato i principali effetti ambientali e di conseguenza i reperti scheletrici assumono grande importanza nell'indagine dei processi evolutivi. Oggi le moderne tecniche di indagini quantitative delle principali caratteristiche morfologiche consentono di metterle in relazione con la variabilità genetica. La posizione geografica della Sicilia, l'isolamento e la sua lunga e dinamica storia di colonizzazione (diversi e numerosi contributi culturali e biologici) hanno creato un contesto peculiare che consente uno studio antropologico unico, utile per sottrarre informazioni importanti sul “Flusso Migratorio” e il conseguente "Influenza delle Popolazioni" sui resti scheletrici umani. Questo progetto si basa sull'analisi antropologica delle ossa umane provenienti da diverse popolazioni (indigene e colonizzatori) distribuite dal Paleolitico all'Età Contemporanea. Le più moderne tecniche di Analisi Geometria Morfometrica (ricostruzione 3D) e di Analisi Statistica Multivariata sono state applicate su tre diversi caratteri scheletrici (Denti, Crani e Statura). L'obiettivo del progetto è quello di eseguire un'ampia analisi della Biodiversità Umana Siciliana al fine di: - Analizzare i dati odontometrici 2D con tecniche multivariate per esplorare le relazioni tra i popoli nel corso dei secoli. - Usare modelli 3D e la morfometria cranio-facciale per studiare la complesso variabilità morfologica relativa alle influenze dei flussi migratori. - Valutare il Secular Trend della Statura. - Usare questi tre caratteri per fornire una panoramica generale della Biodiversità Umana in Sicilia. Il nostro lavoro denota l'affidabilità dei metodi impiegati e come in uno studio sulla biodiversità diversi caratteri sono indispensabili per comprendere il processo evolutivo. I dati forniti dimostrano anche la correlazione tra i caratteri morfologici XI e l'influenza esercitata (non solo dai fattori ambientali) dal flusso umano sul fenotipo. I risultati mostrano chiaramente come tutti i caratteri valutati siano coinvolti allo stesso tempo nello stesso processo di diversificazione. Le variazioni morfologiche mostrano una generale diminuzione del prognatismo mascellare e una leggera mesocefalizzazione con il cranio che diventa più stretto e leggermente e meno allungato e il viso che diventa più largo e più corto. Considerando sempre l’influenza del rapporto dimensione/composizione sia l'analisi statistica canonica che quella multivariata, supportano la teoria che i coloni del Paleolitico superiore di San Teodoro potrebbero ragionevolmente essere la prima prova di colonizzazione umana in Sicilia (questa teoria è anche supportata dai campioni Mesolitici che clusterizzano separati dai primi). Significativi sono i periodi del Bronzo della transizione Bronzo/Ferro nei quali assistiamo ad importanti cambiamenti morfologici (Denti, Crani e Stature) dovuti a “Flussi Migratori” costanti e numericamente significativi. Questa variazione coincide esattamente con i primi “Afflussi di Popolazione” stabili conseguenti alle migrazioni umane dal continente. Tuttavia i campioni preistorici di alcune popolazioni, conservano alcuni caratteri arcaici anche dopo l'Età del Ferro (Era Storica) mentre la "Continuità di Popolazione" (conseguente alla convivenza e agli alternamenti delle diverse colonizzazioni) dall'Antichità al Medioevo ha prodotto un progressivo aumento della variabilità senza grandi variazione tra Eignevalue e Componenti Principali. L'assenza di relazione interna causata dall'intricato periodo di colonizzazione è invece presente sul campione preistorico sul quale si riscontra una netta variazione tra i PC. Le correlazioni tra "Afflusso di popolazione" e Variabilità sono osservabili anche nell'influenza dei coloni islamici sugli indigeni durante il Medioevo. Tuttavia, l'ampia variabilità e il morfospazio omogeneo mostrano che dopo questi gruppi (fino ai Contemporanei) sono riconoscibili popolazioniben definite.[ES] Durante los últimos 200.000 años, la especie humana se ha extendido por toda la Tierra, adaptando su morfología y fisiología a una amplia variedad de hábitats. Por tanto, el esqueleto humano ha registrado los principales efectos ambientales. Hoy las modernas técnicas de investigaciones cuantitativas de las principales características morfológicas nos permiten relacionarlas con la variabilidad genética. La posición geográfica de la Sicilia, su aislamiento y su larga y dinámica historia de colonización han creado un contexto peculiar que permite un estudio antropológico único, útil para extraer información importante sobre el "Flujo Migratorio" y "Influencia Población". Este proyecto se basa en la análisis antropológica de huesos humanos de diferentes poblaciones (indígenas y colonizadoras). Las técnicas de Análisis de Geometría Morfométrica y Análisis Estadístico Multivariante se han aplicado en tres caracteres esqueléticos diferentes (Dientes, Cráneos y Estatura). El objetivo del proyecto es realizar un análisis amplia de la Biodiversidad Humana Siciliana con el fin de: - Analizar datos odontométricos 2D con técnicas multivariadas para explorar las relaciones entre pueblos entre los siglos. - Utilizar modelos 3D y la morfometría craneofacial para estudiar la compleja variabilidad morfológica relacionada con los flujos migratorios. - Evaluar la tendencia secular de la estatura. - Utilizar estos tres caracteres para proporcionar una descripción general de la Biodiversidad Humana en Sicilia. Esto trabajo denota la confiabilidad de los métodos utilizados y, como en un estudio de la biodiversidad, varios caracteres son indispensables para comprender el proceso evolutivo. Los datos también demuestran la correlación entre los caracteres morfológicos y la influencia (no solo por factores ambientales) de los flujos humanos sobre el fenotipo. Los resultados muestran claramente que todos los caracteres evaluados están involucrados al mismo tiempo en el mismo proceso de diversificación. Las variaciones morfológicas muestran una disminución general del prognatismo maxilar y una ligera mesocefalilización con el cráneo que se convierte en más estrecho y ligeramente y menos alargado y la cara más ancha y corta. Siempre considerando la influencia de la relación tamaño/composición, de la muestra, tanto el análisis estadístico canónico como multivariado apoyan la teoría que la población del Paleolítico Superior de San Teodoro podría ser razonablemente la primera evidencia de colonización humana en Sicilia (esta teoría también es apoyada de la muestra Mesolítica que se agrupa separada). Son significativos los periodos de el Bronce y de la transición Bronce/Hierro en los que asistimos a importantes cambios morfológicos (Dientes, Cráneos y Estatura) debido a los constantes y numéricamente significativos "Flujos Migratorios". Esta variación coincide exactamente con los primeros "Flujos de Población" estables como consecuencia de las migraciones humanas desde el continente. Sin embargo, las muestras Prehistóricas de algunas poblaciones conservan algunas características arcaicas incluso después de la Edad del Hierro (Era Histórica) mientras la "Continuidad de la Población" (resultante de la coexistencia y alternancia de la colonización) desde la Antigüedad hasta la Edad Media produjo una mayor progresiva variabilidad sin pero mayor variación entre Eignevalue y Componentes Principales. La ausencia de relación interna causada por el intrincado período de colonización está presente en la muestra prehistórica en la que hay una clara variación entre las Componentes Principales. Las correlaciones entre la "Afluencia de Población" y la Variabilidad también se pueden observar en la influencia de los colonos Islámicos sobre los indígenas durante la Edad Media. Sin embargo, la amplia variabilidad y el morfoespacio homogéneo muestran que poblaciones bien definidas no son reconocibles después de estos grupos (hasta los contemporáneos).[EN] During the last 200,000 years, human species has spread throughout Earth, adapting their morphology and physiology to a wide range of habitats. The human skeleton has therefore, recorded the main environmental effects. Nowadays modern quantitative investigations of the main morphological features permit us to relate them with the genetic variability. The Sicilian geographic position, isolation and its long and dynamic history of colonization) made a peculiar context that allows a unique anthropological study, useful to sign-out important information about the "Migratory Flow" and the consequent "Populations Influx". This project is based on the Anthropological Analysis of the human bones coming from different populations distributed from Paleolithic to the Contemporary Age. The techniques of Morphometric Geometric analysis and Multivariate Statistic Analysis were applied over three different catchers (Teeth, Skulls and Stature). The project aim is to perform a wide analysis of the Sicilian Human Biodiversity in order to: - Analyze 2D odontometrics data with multivariate techniques to explore the relationships between the peoples over the centuries. - Use 3D models and skull-facial morphometry to study the complex morphological variability concerning the "Populations". - Evaluate the "Stature's Secular Trend". - Use these three characters to provide a general overview of the human biodiversity in Sicily. Our work denotes the reliable of the methods employed underlying as in a study of biodiversity several characters are indispensable to understand the evolutionary process. Data also provided to demonstrate the correlation between the morphological characters and the influence carried (not only by the environmental factors) by the human flow on the phenotype. Results clearly shows as all the characters evaluated are at the same time involved in the same process of diversification. Morphological variations show a general decrease of Maxilla Prognathism and a soft Mesocephalization with the skull that becomes tighter and slightly and less elongated and the face that become wider and shorter. Always considering simple size/composition both Canonical and Multivariate Statistics Analysis display, as the Upper-Paleolithic Würm-Settlers of San Teodoro could reasonably be the first evidence of human colonization in Sicily (this theory is supported by the Mesoltitch Hunter-Gatherers specimens clustered separated from the first one). Meaningful is the periods of Bronze/Iron transition in we assist to the prime plainness of morphological changes (teeth, skulls and statures) due to the constant and numerically significative "Migratory Flows". This variation exactly coincides with the first "Population Influx" consequent of the human migrations from the continent. Instead, Prehistorical samples of some populations, keep some archaic characters after Iron Age (Historical Era) the "Population Continuity" (consequent of the cohabitation and alternations of the several Mediterranean populations) from Antiquity to Middle Ages produced a progressive increase of variability without big variation among Eigenvalue and Principal Component. The absence of internal relationship caused by the intricate colonization period is on the contrary present on Prehistorichal sample on which we can find a clear variation between the PC. Correlations between "Population Influx" and Variability are also observable on the influence of Islamic settlers on the Indigenous during the Middle Ages. However, the wide variability and the homogenous morphospace showed by these groups and the Contemporary resulted in no well-defined populations.[CA] Durant els últims 200.000 anys, l'espècie humana s'ha estés per tota la Terra, adaptant la seua morfologia i fisiologia a una àmplia varietat d'hàbitats. Per tant, l'esquelet humà ha registrat els principals efectes ambientals. Hui les modernes tècniques d'investigacions quantitatives de les principals característiques morfològiques ens permeten relacionar-les amb la variabilitat genètica. La posició geogràfica de la Sicília, el seu aïllament i la seua llarga i dinàmica història de colonització han creat un context peculiar que permet un estudi antropològic únic, útil per a extraure informació important sobre el "Flux Migratori" i "Influència Població". Aquest projecte es basa en l'anàlisi antropològica d'ossos humans de diferents poblacions des del Paleolític fins a l'Edat Contemporània. Les tècniques d'Anàlisis de Geometria Morfomètrica (reconstrucció 3D) i Anàlisi Estadística Multivariante s'han aplicat en tres caràcters esquelètics diferents (Dents, Cranis i Alçada). L'objectiu del projecte és realitzar una anàlisi àmplia de la Biodiversitat Humana Siciliana amb la finalitat de: - Analitzar dades odontométricos 2D amb tècniques multivariades per a explorar les relacions entre pobles entre els segles. - Utilitzar models 3D i la morfometria craniofacial per a estudiar la complexa variabilitat morfològica relacionada amb els fluxos migratoris. - Avaluar la tendència secular de l'alçada. - Utilitzar aquests tres caràcters per a proporcionar una descripció general de la Biodiversitat Humana a Sicília. Això treball denota la confiabilitat dels mètodes utilitzats i, com en un estudi de la biodiversitat, diversos caràcters són indispensables per a comprendre el procés evolutiu. Les dades també demostren la correlació entre els caràcters morfològics i la influència (no sols per factors ambientals) dels fluxos humans sobre el fenotip. Els resultats mostren clarament que tots els caràcters avaluats estan involucrats al mateix temps en el mateix procés de diversificació. Les variacions morfològiques mostren una disminució general del prognatisme maxil·lar i una lleugera mesocefalilización amb el crani que es converteix en més estret i lleugerament i menys allargat i la cara més ampla i tala. Sempre considerant la influència de la relació grandària/composició, de la mostra, tant l'anàlisi estadística canònica com multivariat donen suport a la teoria que la poblacion del Paleolític Superior de Sant Teodoro podria ser raonablement la primera evidència de colonització humana a Sicília (aquesta teoria també és secundada de la mostra Mesolítica que s'agrupa separada). Són significatius els períodes del Bronze i de la transició Bronze/Ferro en els quals assistim a importants canvis morfològics (Dents, Cranis i Alçada) a causa dels constants i numèricament significatius "Fluxos Migratoris". Aquesta variació coincideix exactament amb els primers "Fluxos de Població" estables com a conseqüència de les migracions humanes des del continent. No obstant això, les mostres Prehistòriques d'algunes poblacions conserven algunes característiques arcaiques fins i tot després de l'Edat del Ferro (Era Històrica) mentre la "Continuïtat de la Població" (resultant de la coexistència i alternança de la colonizacion) des de l'Antiguitat fins a l'Edat mitjana va produir una major progressiva variabilitat sense però major variació entre Eignevalue i Components Principals. L'absència de relació interna causada per l'intricat període de colonització està present, en contrero, en la mostra prehistòrica en la qual hi ha una clara variació entre les Components Principals. Les correlacions entre l' "Afluència de Població" i la Variabilitat també es poden observar en la influència dels colons Islàmics sobre els indígenos durant l'Edat mitjana. No obstant això, l'àmplia variabilitat i el morfoespacio homogeni mostren que poblacions ben definides no són recognoscibles després d'aquests grups (fins als contemporanis).Thanks to: Dr. Francesa Spatafora (Archaeological Museum “A. Salinas”, Palermo, Sicily, Italy), Dr. Maria Grazia Griffo (Archaeological Museum “Baglio Anselmi”. Marsala, Sicily, Italy) , Dr. Maria Amalia Mastelloni (Archaeological Museum “Bernabò-Brea", Aeolian Island, Sicily, Italy) and Dr. Carolina Di Patti (Geological University Museum of Palermo “Gemmellaro”, Sicily, Italy) for the authorization to study the materials. Thanks to Prof. Armando González Martín, Prof. Oscar Cambra-Moo Laboratorio de Poblaciones del Pasado (LAPP), Universidad Autónoma de Madrid (UAM), Madrid, Spain) for the invaluable help. Thanks to the Laboratorio de Ecología Evolutiva Humana (LEEH) - Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Buenos Aires, Argentina), to all the laboratoy directors to provide the modern specimens of reference sample. Thanks to the Mayor Mr. Domenico Giannopolo, the council member of cultural heritage Mrs. Nieta Gennuso and Dr. Filippo Ianni (Municipality of Caltavuturo, Sicily, Italy) for the excavation seasons and the authorization to study the materials. To the Museum of Mozia. (Sicily, Italy), The Whitaker foundation and Dr. Pamela Toti for the authorization to study the materials. To the Soprintendenza BB.CC.AA. di Palermo. (Sicily, Italy) Dr. Stefano Vassallo and Dr. Maria Grazia Cucco for the opportunity of the excavations in Caltavuturo and authorization to study the materials. Thanks to the Soprintendenza BB.CC.AA. di Trapani. (Sicily, Italy), Soprintendente and Dr. Rossella Giglio, Township Museum of Mussomeli. (Sicily, Italy), and Prof. Erich Kistler and Dr. Nicole Mölk (University of Innsbruck, Austria, Innsbruck) for the authorization to study the materials.Lauria, G. (2020). The Human Biodiversity in the Middle of the Mediterranean. Study of native and settlers populations on the Sicilian context [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/159789TESI

    Some considerations on coastal processes relevant to sea level rise

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    The effects of potential sea level rise on the shoreline and shore environment have been briefly examined by considering the interactions between sea level rise and relevant coastal processes. These interactions have been reviewed beginning with a discussion of the need to reanalyze previous estimates of eustatic sea level rise and compaction effects in water level measurement. This is followed by considerations on sea level effects on coastal and estuarine tidal ranges, storm surge and water level response, and interaction with natural and constructed shoreline features. The desirability to reevaluate the well known Bruun Rule for estimating shoreline recession has been noted. The mechanics of ground and surface water intrusion with reference to sea level rise are then reviewed. This is followed by sedimentary processes in the estuaries including wetland response. Finally comments are included on some probable effects of sea level rise on coastal ecosystems. These interactions are complex and lead to shoreline evolution (under a sea level rise) which is highly site-specific. Models which determine shoreline change on the basis of inundation of terrestrial topography without considering relevant coastal processes are likely to lead to erroneous shoreline scenarios, particularly where the shoreline is composed of erodible sedimentary material. With some exceptions, present day knowledge of shoreline response to hydrodynamic forcing is inadequate for long-term quantitative predictions. A series of interrelated basic and applied research issues must be addressed in the coming decades to determine shoreline response to sea level change with an acceptable degree of confidence. (PDF contains 189 pages.

    Pathways for cross-boundary effects of biodiversity on ecosystem functioning

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    The biodiversity-ecosystem functioning concept asserts that processes in ecosystems are markedly influenced by species richness and other facets of biodiversity. However, biodiversity-ecosystem functioning studies have been largely restricted to single ecosystems, ignoring the importance of functional links - such as the exchange of matter, energy, and organisms - between coupled ecosystems. Here we present a basic concept and outline three pathways of cross boundary biodiversity effects on ecosystem processes and propose an agenda to assess such effects, focusing on terrestrial-aquatic linkages to illustrate the case. This cross-boundary perspective of biodiversity-ecosystem functioning relationships presents a promising frontier for biodiversity and ecosystem science with repercussions for the conservation, restoration, and management of biodiversity and ecosystems from local to landscape scales.Peer reviewe
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