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Barend Van Maanen Giovanni Coco rew Swales Karin R. Bryan 《New Zealand geographer》2008,64(2):162-164
Abstract: Biomorphodynamic interactions, the feedback loops that operate between physical processes, biology and morphology, affect the long-term evolution of estuaries. This paper outlines how consideration of such interactions and implementation through innovative modelling techniques can become the next crucial step needed to advance understanding of estuarine evolution. 相似文献
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Barend Köbben Rolf De By Theodor Foerster Otto Huisman Rob Lemmens Javier Morales 《Transactions in GIS》2010,14(Z1):25-37
ITC, the Faculty of Geo–Information Science and Earth Observation of the University of Twente, is an institute that aims at capacity building and institutional development, specifically in developing countries. In our Geoinformatics curriculum, we emphasise two principles. The first addresses the systematics of purposeful spatial data production and uptake into computerised systems; the second addresses the methodical construction of these computerised systems, applying principles of model – driven architecture, formal specification and transformational design of SDI nodes. The term Spatial Data Infrastructure (SDI) usually denotes large, complex systems, but its principles can also be applied in simple and cost–effective ways. This approach we have called SDIlight and it is of particular interest to our students that come from developing countries. We work with and build a software stack consisting of free and open source components. To achieve interoperability, we emphasise the use of open standards from the Open Geospatial Consortium and others. In this paper, we explain how our students apply the SDIlight approach in the GeoinformaticsMaster degree course. An important part of that course is a Case Study Application Building & Programming, in which students apply their knowledge in a ‘real–world’ project, with a focus on geo–information engineering skills. We conclude with a section that evaluates the effectiveness of using the SDIlight concept in teaching our Geoinformatics Master, and on the more general applicability of the methodology. 相似文献
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van Maanen Barend Coco Giovanni Bryan Karin R. Friedrichs Carl T. 《Ocean Dynamics》2013,63(11):1249-1262
Sea-level rise has a strong influence on tidal systems, and a major focus of climate change effect studies is to predict the future state of these environmental systems. Here, we used a model to simulate the morphological evolution of tidal embayments and to explore their response to a rising sea level. The model was first used to reproduce the formation of channels and intertidal flats under a stable mean water level in an idealised and initially unchannelled tidal basin. A gradual rise in sea level was imposed once a well-developed channel network had formed. Simulations were conducted with different sea-level rise rates and tidal ranges. Sea-level rise forced headward erosion of the tidal channels, driving a landward expansion of the channel network and channel development in the previously non-inundated part of the basin. Simultaneously, an increase in channel drainage width in the lower part of the basin occurred and a decrease in the overall fraction of the basin occupied by channels could be observed. Sea-level rise thus altered important characteristics of the tidal channel network. Some intertidal areas were maintained despite a rising sea level. However, the size, shape, and location of the intertidal areas changed. In addition, sea-level rise affected the exchange of sediment between the different morphological elements. A shift from exporting to importing sediment as well as a reinforcement of the existing sediment export was observed for the simulations performed here. Sediment erosion in the inlet and the offshore transport of sediment was enhanced, resulting in the expansion of the ebb-tidal delta. Our model results further emphasise that tidal embayments can exhibit contrasting responses to sea-level rise.
相似文献5.
Andreas Iordanidis Jan Schwarzbauer Andreas Georgakopoulos Barend van Lagen 《Geochemistry International》2012,50(2):159-178
Several lignite samples were collected from boreholes of the Amynteo opencast lignite mine, northern Greece. Organic geochemical
characteristics were investigated with the help of various analytical techniques, comprising Gas Chromatography (GC) and Gas-chromatography-Mass
Spectrometry (GC-MS), Fourier Transform Infrared Spectroscopy (FTIR), solid-state Nuclear Magnetic Resonance (NMR) and Electron
Paramagnetic Resonance (EPR) spectroscopy, petrographical measurements as well as determination of bulk parameters. In the
low rank (Rr = 0.21%) Amynteo lignites, huminite is the most abundant maceral group, inertinite has relatively low percentages
and liptinite concentrations are rather high. Carbon Preference Index (CPI) reveals the predominance of odd-numbered, long-chained
aliphatic hydro-carbons, which is related to a higher terrestrial plant input. The Pr/Ph ratio suggests that reducing conditions
were persistent during peatification. Gymnosperm biomarkers such as isoprimarane, abietane, phyllocladane and sandaracopimarane,
as well as angiosperm indicators (lupane) and hopanoid compounds with bacterial origin were identified. Analyses of the aromatic
fractions revealed the presence of naphthalene, alkyl benzenes and phenols, pyrene, cadalene, cadinane, fluoranthene and dibenzofurane.
Based on the FTIR analysis, aliphatic and oxygen containing structures were prevailed over the aromatic moieties. The intensity
of the mineral bands was preferentially increased in the FTIR spectra of insoluble material. According to NMR analysis, the
aliphatic carbons (0–50 ppm) have higher proportions comparing to aromatic carbons (100–160 ppm). The aromaticity fraction
is low (fa = 0.32), as expected for these low rank coals. The presence of free organic radicals and Fe3+ and Mn2+ paramagnetic ions was revealed by EPR. In summary, the combined application of complementary analytical techniques allowed
a deep inside into the geochemical characteristics of Amynteo lignites. 相似文献
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Barend van Maanen Giovanni Coco Karin R. Bryan Carl T. Friedrichs 《Ocean Dynamics》2013,63(11-12):1249-1262
Sea-level rise has a strong influence on tidal systems, and a major focus of climate change effect studies is to predict the future state of these environmental systems. Here, we used a model to simulate the morphological evolution of tidal embayments and to explore their response to a rising sea level. The model was first used to reproduce the formation of channels and intertidal flats under a stable mean water level in an idealised and initially unchannelled tidal basin. A gradual rise in sea level was imposed once a well-developed channel network had formed. Simulations were conducted with different sea-level rise rates and tidal ranges. Sea-level rise forced headward erosion of the tidal channels, driving a landward expansion of the channel network and channel development in the previously non-inundated part of the basin. Simultaneously, an increase in channel drainage width in the lower part of the basin occurred and a decrease in the overall fraction of the basin occupied by channels could be observed. Sea-level rise thus altered important characteristics of the tidal channel network. Some intertidal areas were maintained despite a rising sea level. However, the size, shape, and location of the intertidal areas changed. In addition, sea-level rise affected the exchange of sediment between the different morphological elements. A shift from exporting to importing sediment as well as a reinforcement of the existing sediment export was observed for the simulations performed here. Sediment erosion in the inlet and the offshore transport of sediment was enhanced, resulting in the expansion of the ebb-tidal delta. Our model results further emphasise that tidal embayments can exhibit contrasting responses to sea-level rise. 相似文献
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This paper presents the first high resolution temperature data from a small Agrostis magellanica mire on subantarctic Marion Island as part of an ongoing island‐wide monitoring project on subsurface ground temperature variability. Variations in ground temperatures were found to be directly linked to the passage of synoptic scale weather systems that influence thermal characteristics and heat fluxes especially in the upper 30 cm of the mire. Preliminary data published here suggest that shallow temperatures will be most affected by changes in synoptic climate that Marion Island is currently experiencing with an increase in average temperatures and a reduction in temperature variability with depth. This study proposes that to effectively detect the ecosystem responses to climate change in a maritime sub‐Antarctic environment the temporal scale of measurement needs to be at least on a diurnal scale to be effective. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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