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Forecasting Uv Index By Neoplanta Model: Methodology And Validation, S. Malinoviç, Dragutin T. Mihailović, Z. Mijatoviç, D. Kapor, I. D. Arseniç Jul 2004

Forecasting Uv Index By Neoplanta Model: Methodology And Validation, S. Malinoviç, Dragutin T. Mihailović, Z. Mijatoviç, D. Kapor, I. D. Arseniç

International Congress on Environmental Modelling and Software

A major consequence of decreasing stratospheric ozone is the increase of solar ultraviolet radiation (UV) passing through the atmosphere. Ultraviolet radiation is very harmful to the entire ecosystem, including health of the human population and for that reason, in the last few decades, scientists have placed a large emphasis on monitoring UV radiation and development and use of estimation procedures. Model NEOPLANTA estimates UV irradiance under cloudless conditions on a horizontal surface and computes the UV index. Model includes effects of the absorption of UV radiation by ozone, SO2 and NO2 and absorption and scattering by aerosol and air molecules …

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Cellular Automata Modelling Of Seagrass In The Orbetello Lagoon, Stefano Marsili-Libelli, E. Giusti Jul 2004

Cellular Automata Modelling Of Seagrass In The Orbetello Lagoon, Stefano Marsili-Libelli, E. Giusti

International Congress on Environmental Modelling and Software

This paper describes the evolution in time and space of wigeongrass (Ruppia maritima) meadows in the Orbetello lagoon, in central Italy, where the control of the submerged vegetation, with a critical coexistence between macroalgae and macrophytes, is the key management problem. While macroalgae are liable to cause dystrophic crises, macrophytes oxygenate and stabilise the sediment and thus control the nutrient flux into the water. This model was developed for the Orbetello Lagoon Managerial Office to predict the development of both groups and test the actions to favour macrophytes over macroalgae, in the context of a decision support system. A previous …

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Incorporating Level Set Methods In Geographical Information Systems (Gis) For Land-Surface Process Modeling, D. Pullar Jul 2004

Incorporating Level Set Methods In Geographical Information Systems (Gis) For Land-Surface Process Modeling, D. Pullar

International Congress on Environmental Modelling and Software

Land-surface processes include a broad class of models that operate at a landscape scale. Currentmodelling approaches tend to be specialised towards one type of process, yet it is the interaction of processesthat is increasing seen as important to obtain a more integrated approach to land management. This paperpresents a technique and a tool that may be applied generically to landscape processes. The technique tracksmoving interfaces across landscapes for processes such as water flow, biochemical diffusion, and plantdispersal. Its theoretical development applies a Lagrangian approach to motion over a Eulerian grid space bytracking quantities across a landscape as an evolving front. …

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Ecoregion Classification Using A Bayesian Approach And Model-Based Clustering, D. Pullar, S. Low Choy, W. Rochester Jul 2004

Ecoregion Classification Using A Bayesian Approach And Model-Based Clustering, D. Pullar, S. Low Choy, W. Rochester

International Congress on Environmental Modelling and Software

Ecological regions are increasingly used as a spatial unit for planning and environmentalmanagement. It is important to define these regions in a scientifically defensible way to justify any decisionsmade on the basis that they are representative of broad environmental assets. The paper describes amethodology and tool to identify cohesive bioregions. The methodology applies an elicitation process toobtain geographical descriptions for bioregions, each of these is transformed into a Normal density estimateon environmental variables within that region. This prior information is balanced with data classification ofenvironmental datasets using a Bayesian statistical modelling approach to objectively map ecological regions.The method is called …

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A Methodology For Knowledge Reuse: Application In The Automatic Generation Of Operational Protocols For Wastewater Treatment Plants, Clàudia Turon, Manel Poch, Ulises Cortés Jul 2004

A Methodology For Knowledge Reuse: Application In The Automatic Generation Of Operational Protocols For Wastewater Treatment Plants, Clàudia Turon, Manel Poch, Ulises Cortés

International Congress on Environmental Modelling and Software

During the preliminary stages of many engineering design tasks, the underlying search space isunbounded and inexact. Initial decisions are made when information is incomplete and many goals arecontradictory. This sort of problem appeared in Catalonia for the identification of appropriate wastewatertreatment systems in small communities, as well as for proposing appropriate operational and maintenanceprotocols to these facilities. In this case, the Catalan Water Agency proposed to develop two EnvironmentalDecision Support Systems (EDSS), one to support the selection of the optimal treatment (EDSS-treatment)and another one to support the definition of appropriated operational and maintenance guides (EDSSmaintenance).This paper presents a methodology for …

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Developing Tools For Adaptive Integrated Water Resource Management In A Semi Arid Region: Possibilities, Probabilities And Uncertainties., Denise Eisenhuth, Juan Bellot, Andreu Bonet, Juan R. Sánchez Jul 2004

Developing Tools For Adaptive Integrated Water Resource Management In A Semi Arid Region: Possibilities, Probabilities And Uncertainties., Denise Eisenhuth, Juan Bellot, Andreu Bonet, Juan R. Sánchez

International Congress on Environmental Modelling and Software

The objective of the AQUADAPT Project (www.aquadapt.net) is to develop strategic toolsto inform adaptive integrated water resource policy using a co-evolutionary approach. In Spain amethodology has been developed in the framework of an integrative study to identify evidence of coevolutionaryprocesses between the hydrological system and the water-using communities of the MarinaBaixa over a period of 50 years. The Marina Baixa is comprised of 18 municipalities each with radicallydifferent land-use patterns spread over an area of 671km2. The research task is complicated by the factthat Spain is a country that is currently debating the merits of a move from demand management …

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Interspecific Segregation And Phase Transition In A Lattice Ecosystem With Intraspecific Competition, K. Tainaka, M. Kushida, Y. Ito, J. Yoshimura Jul 2004

Interspecific Segregation And Phase Transition In A Lattice Ecosystem With Intraspecific Competition, K. Tainaka, M. Kushida, Y. Ito, J. Yoshimura

International Congress on Environmental Modelling and Software

Many empirical studies of ecological community indicate the coexistence of competing species isextremely common in nature. However, many mathematical studies show that coexistence of competitivespecies is not so easy. In the present article, we focus on the segregation of habitat (microhabitat). If habitatsof species are spatially separated, they can coexist easily: under the habitat segregation, net competition doesnot work between species. We study a lattice ecosystem composed of two competitive species. The dynamicsof this system is found to be asymptotically stable. In this system both species can coexist, becauseintraspecific competition is stronger than interspecific competition. It is found that this …

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Ict Requirements For An ‘Evolutionary’ Development Of Wfd Compliant River Basin Management Plans, M. Blind Jul 2004

Ict Requirements For An ‘Evolutionary’ Development Of Wfd Compliant River Basin Management Plans, M. Blind

International Congress on Environmental Modelling and Software

The Water Framework Directive (WFD) poses an immense challenge to integrated water man-agement in Europe. Aiming at a “good ecological status” of all water resources in 2015, integrated river ba-sin management plans need to be in place by 2009, and need to be broadly supported by stakeholders. Cost effective programmes of measures must be put in place to meet the objective of “good ecological status”. These measures reach beyond the direct water domain and touch on fields such as spatial planning, public participation and socio-economics. Much information and knowledge needs to be available to create these plans. Information and Communication …

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Empirical Evaluation Of Decision Support Systems: Concepts And An Example For Trumpeter Swan Management, Richard S. Sojda Jul 2004

Empirical Evaluation Of Decision Support Systems: Concepts And An Example For Trumpeter Swan Management, Richard S. Sojda

International Congress on Environmental Modelling and Software

Decision support systems are often not empirically evaluated, especially the underlying modelling components. This can be attributed to such systems necessarily being designed to handle complex and poorly structured problems and decision making. Nonetheless, evaluation is critical and should be focused on empirical testing whenever possible. Verification and validation, in combination, comprise such evaluation. Verification is ensuring that the system is internally complete, coherent, and logical from a modelling and programming perspective. Validation is examining whether the system is realistic and useful to the user or decision maker, and should answer the question: “Was the system successful at addressing its …

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An Interactive Spatial Optimisation Tool For Systematic Landscape Restoration, Brett A. Bryan, L. M. Perry, D. Gerner Jul 2004

An Interactive Spatial Optimisation Tool For Systematic Landscape Restoration, Brett A. Bryan, L. M. Perry, D. Gerner

International Congress on Environmental Modelling and Software

This paper describes the design and construction of a prototype spatial decision support system (SDSS) for an interactive evaluation of integrated landscape restoration planning using spatial information technology. Landscape planning involves spatially explicit decisions about the types of landuses allowable, and the extent and location of these landuses. This decision-making needs to be supported by accurate and detailed information about the spatial distribution of numerous parameters affecting the distribution of landuse. The SDSS that we present in this paper comprises a geographic information system (GIS) tightly coupled with an analytical optimisation module by means of an interactive interface. The GIS …

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Strategic Environmental Assessment (Sea) As A Participatory Approach To Environmental Planning Experiences From A Case Study With Sea In Waste Management, Stefan Salhofer, Gudrun Wassermann, Erwin Binner Jul 2004

Strategic Environmental Assessment (Sea) As A Participatory Approach To Environmental Planning Experiences From A Case Study With Sea In Waste Management, Stefan Salhofer, Gudrun Wassermann, Erwin Binner

International Congress on Environmental Modelling and Software

A Strategic Environmental Assessment (SEA) is conducted to ensure that the environmentalconsequences of plans or programs (land use programs, traffic planning, waste management planning etc.) areidentified and assessed. Participation is a mandatory element of the SEA process. All affected parties arerequired to be represented in the process. Until today, the SEA process has been applied to wastemanagement in only a few cases. This paper describes the assessment of a waste management plan in theprovince of Salzburg, Austria. The process took place in 2003. As in other cases of SEA, several alternativeswere considered and assessed. Participation involved the establishment of a …

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Implementation Of The Streames Environmental Decision-Support System, David Cabanillas, Esther Llorens, Joaquim Comas, Manel Poch, Luigi Ceccaroni, Steven Willmott Jul 2004

Implementation Of The Streames Environmental Decision-Support System, David Cabanillas, Esther Llorens, Joaquim Comas, Manel Poch, Luigi Ceccaroni, Steven Willmott

International Congress on Environmental Modelling and Software

As part of the European-Commission--funded STREAMES project, a system is being developed with the objective of capturing knowledge from water managers and environmental-science experts, regarding nutrients-excess effects in streams and of combining this knowledge into a user-friendly tool to assist water managers in evaluating streams’ nutrient-retention capabilities. In this paper, we summarize the decision-support knowledge components which have been identified in previous work and, based on these, present an implementation of a prototype of an environmental decision-support system. The decision support provided by the system to water managers consists of: (1) diagnosis: inferring possible stream problems, assessing the alteration degree …

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Assessing Management Systems For The Conservation Of Open Landscapes Using An Integrated Landscape Model Approach, M. Rudner, R. Biedermann, B. Schröder, M. Kleyer Jul 2004

Assessing Management Systems For The Conservation Of Open Landscapes Using An Integrated Landscape Model Approach, M. Rudner, R. Biedermann, B. Schröder, M. Kleyer

International Congress on Environmental Modelling and Software

The aim of the MOSAIK-project is to test alternative management systems regarding theirefficiency in maintaining the characteristic species composition of dry grasslands. We present an integratedlandscape model approach to test an alternative management system for applicability in preserving drygrasslands. By rototilling, i.e. cyclic, massive disturbance in the vegetation cover, we established a controlledmosaic cycle comprising a successional series from heavily disturbed areas to grassland and shrubs. Thedisturbance regime affects the landscape on different temporal and spatial scales. The resulting shiftingmosaics determine the habitat qualities for plant and animal species. Changes in habitat quality may reducethe survival of local or regional …

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A Fast Evolutionary-Based Meta-Modelling Approach For The Calibration Of A Rainfall-Runoff Model, Soon-Thiam Khu, Dragan Savic, Yang Liu, Henrik Madsen Jul 2004

A Fast Evolutionary-Based Meta-Modelling Approach For The Calibration Of A Rainfall-Runoff Model, Soon-Thiam Khu, Dragan Savic, Yang Liu, Henrik Madsen

International Congress on Environmental Modelling and Software

Population-based search methods such as evolutionary algorithm, shuffled complex algorithm, simulated annealing and ant colony search are increasing used as automatic calibration methods for a wide range of water and environmental simulation models. However, despite the advances in computer power, it may still be impractical to rely exclusively on computationally expensive (time consuming) simulation for many real world complex problems. This paper proposed the use of meta-models to replace numerical simulation models for the purpose of calibration. Meta-models are essentially “model of the model”. The meta-model used in this study is the artificial neural network and, when coupled with genetic …

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Infiltration Of Stormwater In A Rain Garden: Richards Equation Numerical Model And Field Experiment, Alejandro R. Dussaillant Jul 2004

Infiltration Of Stormwater In A Rain Garden: Richards Equation Numerical Model And Field Experiment, Alejandro R. Dussaillant

International Congress on Environmental Modelling and Software

Traditional stormwater management does not mitigate groundwater depletion resulting from groundwater pumping and reduction in recharge. Infiltration practices, such as rain gardens, offer a potentially effective approach for addressing groundwater depletion. A rain garden is a landscaped garden in a shallow depression that receives the stormwater from nearby impervious surfaces, focusing recharge. We have developed a numerical model that can be applied in rain garden design and evaluation. Water flow through the rain garden soil is modeled over three layers- a root zone, a middle storage layer of high conductivity, and a subsoil lower layer. To continuously simulate recharge, runoff …

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Eliciting Sources Of Uncertainty In Ecological Simulation Models, V. Brilhante, J. L. Campos Dos Santos Jul 2004

Eliciting Sources Of Uncertainty In Ecological Simulation Models, V. Brilhante, J. L. Campos Dos Santos

International Congress on Environmental Modelling and Software

Uncertainty is an intrinsic feature of complex ecological models. Given that it is not possible to rid the modelsfrom uncertainty, we are left with taking notice of it for consideration in model-based decision making. Traditionalecological modelling methods and tools do not support explicit accounts of model uncertainty. Thiswork gives a contribution towards making known, or bringing to the surface, sources of uncertainty that areembedded in ecological models. The sources of uncertainty are related to the models’ supporting data andequations. A metadata standard is used to specify data-related sources of uncertainty, such as creator and coverage.In the technique developed, models are …

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Simulation Of Stream Flow In The Yantra River Basin, Bulgaria Via A Gis-Based Modeling Approach, T. Hristov, B. Evans, V. Ioncheva Jul 2004

Simulation Of Stream Flow In The Yantra River Basin, Bulgaria Via A Gis-Based Modeling Approach, T. Hristov, B. Evans, V. Ioncheva

International Congress on Environmental Modelling and Software

This paper describes the simulation of stream flow in ungauged watersheds using the computermodel BISTRA (Basin Impacts of Simulated Transport from Rural Areas), developed by the PennsylvaniaState University in collaboration with the Institute of Water Problems, Bulgarian Academy of Sciences. Themain purpose of this GIS-based model is the quantification of diffuse pollution loads at the catchment level.To achieve this, BISTRA contains a sub-model for simulating hydrology in a catchment based on genericclimate and landscape-related factors (e.g., daily precipitation and temperatures, soil, topography, land use,interdependence between surface and underground waters, etc.) which makes it possible to quantify monthlyrunoff, infiltration, and stream …

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A Model Based On Cellular Automata For The Simulation Of The Dynamics Of Plant Populations, Stefania Bandini, Giulio Pavesi Jul 2004

A Model Based On Cellular Automata For The Simulation Of The Dynamics Of Plant Populations, Stefania Bandini, Giulio Pavesi

International Congress on Environmental Modelling and Software

We present a Cellular Automata based model for the simulation of the dynamics of plant populations.The evolution of a plant population in a given area mainly depends on the resources available on the territory(in turn influenced by other factors like sunlight, rain, temperature, and so on) and how different individuals(plants) compete for them. Traditional methods used in this field are continuous and based on differentialequations that model the global evolution of the system: unfortunately, most of the data needed to providereliable parameters for these models are usually scarce and difficult to obtain. The model we present is insteadthought in a …

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Predicting Predation Efficiency Of Biocontrol Agents: Linking Behavior Of Individuals And Population Dynamics, Brigitte Tenhumberg Jul 2004

Predicting Predation Efficiency Of Biocontrol Agents: Linking Behavior Of Individuals And Population Dynamics, Brigitte Tenhumberg

International Congress on Environmental Modelling and Software

Behavioral ecology and population ecology are two separate branches of ecology; studies linkingthe effect of individual behavior and population dynamics are rare. This paper connects a stochastic optimalforaging model of insect predators with an age structured population model of its prey. I modeled syrphidlarvae feeding on cereal aphids, an interaction critical to cereal crops in Germany. The key stochastic elementin this model is the foraging success of predators, which influences survival and developmental time ofpredators and mortality of the prey population. The model predicts that the level of control incurred bypredators is highest if predators arrive when prey numbers are …

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A Bayesian Belief Network For Modelling Brown Trout (Salmo Trutta) Populations In Switzerland, M. E. Borsuk, Peter Reichert, Patricia Burkhardt-Holm Jul 2004

A Bayesian Belief Network For Modelling Brown Trout (Salmo Trutta) Populations In Switzerland, M. E. Borsuk, Peter Reichert, Patricia Burkhardt-Holm

International Congress on Environmental Modelling and Software

A Bayesian belief network is described that integrates the various scientific findings of an interdisciplinary research project on brown trout and their habitat in Switzerland. The network is based on a population model for brown trout, which is extended to include the effect of natural and anthropogenic influence factors. Uncertainty is included in the form of conditional probability distributions describing model relationships. The model is applied to brown trout populations at twelve locations in four river basins. Model testing consisted of comparing predictions of juvenile and adult density under current conditions to the results of recent population surveys. The relative …

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Sustainable Marine Resource Management: Lessons From Viability Analysis, Jürgen Kropp, K. Eisenack, J. Scheffran Jul 2004

Sustainable Marine Resource Management: Lessons From Viability Analysis, Jürgen Kropp, K. Eisenack, J. Scheffran

International Congress on Environmental Modelling and Software

Marine natural resources are under pressure worldwide. Management and surveillance systems are often inappropriate to guarantee a sustainable resource utilization since the knowledge on fisheries and/or stocks is limited. Additionally, institutional failures, e.g. unsuitable regulatory policies, have accelerated resource exploitation in several cases. Modelling is often considered as a very effective tool for studying the behaviour of complex systems, but a variety of difficulties arise if one has to deal with uncertain knowledge or inhomogeneous data of different quality. In this paper we present a method that is capable both for (i) integration of sparse or limited knowledge from different …

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Ecotourism In The Amazon, Beatriz Garcia, José G. Gasques, Eliana T. Bastos Jul 2004

Ecotourism In The Amazon, Beatriz Garcia, José G. Gasques, Eliana T. Bastos

International Congress on Environmental Modelling and Software

This paper presents the development of ecotourism in the Brazilian Amazon from a legalperspective. Firstly, it provides an overview of the Brazilian Amazon and highlights the growing importanceof ecotourism in that region. Secondly, it examines the legal principles and rules on ecotourism at theinternational, regional and national levels. The regulation of ecotourism is crucial. Unregulated ecotourism islikely to cause environmental and social harm, particularly to local and indigenous communities. The legalframework regulating ecotourism activities is still incipient. This activity is generally regulated in an indirectmanner, but it is in any case subject to the general environmental law rules and principles. …

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Interaction Between Hydrodynamics And Mass- Transfer At The Sediment-Water Interface, C. Gualtieri Jul 2004

Interaction Between Hydrodynamics And Mass- Transfer At The Sediment-Water Interface, C. Gualtieri

International Congress on Environmental Modelling and Software

Modeling mass-transfer across the sediment-water interface is a significant issue in environmental hydraulics. In fact diffusional exchanges of solutes between the bed sediment and the overlying water column could greatly affect water quality. Particularly, diffusional flux of dissolved oxygen (DO) towards the bed sediments from the water column could be responsible for low and unacceptable levels of DO in the ecosystem. This flux depends both on sediment and flow characteristics. The objective of the present paper is to investigate the interaction between flow hydrodynamics and dimensionless fluxes of dissolved substances across the sediment-water interface. Therefore, some literature predictive models are …

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Circadian Patterns Recognition In Ecosystems By Wavelet Filtering And Fuzzy Clustering, Stefano Marsili-Libelli, Simone Arrigucci Jul 2004

Circadian Patterns Recognition In Ecosystems By Wavelet Filtering And Fuzzy Clustering, Stefano Marsili-Libelli, Simone Arrigucci

International Congress on Environmental Modelling and Software

This paper presents a method for extracting representative patterns from a set of data representing circadian cycles. The analysis is based on a combination of wavelet filtering and fuzzy clustering. The data are first processed with a discrete wavelet decomposition in order to filter out the noise and isolate the relevant circadian cycle. It is shown that the second level decomposition yields the best cycle approximation, filtering out measurement noise and other artefacts and preserving the main cycle features. From the filtered data the following discriminating features are extracted: minimum and maximum daily values, and the slope of the line …

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Linking Hydrologic Modeling And Ecologic Modeling: An Application Of Adaptive Ecosystem Management In The Everglades Mangrove Zone Of Florida Bay, Jon C. Cline, Jerome J. Lorenz, Eric D. Swain Jul 2004

Linking Hydrologic Modeling And Ecologic Modeling: An Application Of Adaptive Ecosystem Management In The Everglades Mangrove Zone Of Florida Bay, Jon C. Cline, Jerome J. Lorenz, Eric D. Swain

International Congress on Environmental Modelling and Software

The Across Trophic Levels System Simulator (ATLSS) is a suite of ecological models designed to assess the impact of changes in hydrology on biotic components of the southern Florida ecosystem. ATLSS implements a multimodeling approach that utilizes process models for lower trophic levels, structured population models for middle trophic levels (fish and macroinvertebrates), and individual-based models for large consumers. ATLSS requires hydrologic input to assess the effects of alternative proposed restoration scenarios on trophic structure. An ATLSS model (ALFISH) for functional fish groups in freshwater marshes in the Everglades of southern Florida has been extended to create a new model …

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Pub And Data-Based Mechanistic Modelling: The Importance Of Parsimonious Continuous-Time Models, Peter C. Young, Renata J. Romanowicz Jul 2004

Pub And Data-Based Mechanistic Modelling: The Importance Of Parsimonious Continuous-Time Models, Peter C. Young, Renata J. Romanowicz

International Congress on Environmental Modelling and Software

The problem of Prediction in Ungauged Basins (PUB) is intimately linked with the concept of regionalisation; namely the transfer of information from one catchment that is gauged to another that is not. But such regionalisation exercises can be dangerous and should be attempted only with great care. The present paper addresses what the authors believe to be one essential aspect of regionalisation: namely, the importance of considering only ‘top-down’ models that are parametrically efficient (parsimonious) and fully ‘identifiable’ from the available catchment data. We argue further that many mechanistic model parameters are more naturally defined in the context of continuous-time, …

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Simulation Of Dynamic Tree Species Patterns In The Alpine Region Of Valais (Switzerland) During The Holocene, Heike Lischke Jul 2004

Simulation Of Dynamic Tree Species Patterns In The Alpine Region Of Valais (Switzerland) During The Holocene, Heike Lischke

International Congress on Environmental Modelling and Software

The spatio temporal forest landscape model TreeMig is presented. It is based on a forest dynamics model that incorporates spatial variability by frequency distributions for tree densities and light intensities. It also takes into account seed production, intra-specific density regulation and seed dispersal. As a case study, the change of the tree species patterns in the Central-Alpine region of Valais was simulated with the model, using climate anomaly and immigration scenarios. The simulations were run on a grid with 1km x 1km resolution and with a yearly time step during the Holocene in the highly structured and heterogeneous environment of …

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The Coexistence Of Plankton Species With Various Nutrient Conditions: A Lattice Simulation Model, T. Miyazaki, T. Togashi, T. Suzuki, T. Hashimoto, K. Tainaka, J. Yoshimura Jul 2004

The Coexistence Of Plankton Species With Various Nutrient Conditions: A Lattice Simulation Model, T. Miyazaki, T. Togashi, T. Suzuki, T. Hashimoto, K. Tainaka, J. Yoshimura

International Congress on Environmental Modelling and Software

In aquatic ecosystems, species diversity is known to be higher in poor nutrient conditions. Theenrichment of nutrition often induces the loss of biodiversity. This phenomenon is called the paradox ofenrichment, since higher nutrient levels can support more species. Furthermore, the species diversity isusually high in most natural communities of phytoplankton. However, the niches of planktonic algae seemalmost identical in apparently homogeneous, aquatic environments. Therefore, the high species diversity ofphytoplankton is incomprehensible and called the paradox of plankton. Mathematical studies show that localcoexistence of competitive species is rare. In a competitive community, the most superior species eliminatesall the inferior species in …

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Towards An Environmental Dss Based On Spatio-Temporal Markov Chain Approximation, Gerard Balent, Marc Deconchat, Sylvie Ladet, Roger Martin-Clouaire, Regis Sabbadin Jul 2004

Towards An Environmental Dss Based On Spatio-Temporal Markov Chain Approximation, Gerard Balent, Marc Deconchat, Sylvie Ladet, Roger Martin-Clouaire, Regis Sabbadin

International Congress on Environmental Modelling and Software

The aim of this paper is to provide a mathematical model for assessing the influence of forest fragmentation on the dynamics of animal biodiversity in a changing landscape. The model is based on a stochastic, spatially explicit population dynamics model which takes both temporal and spatial dynamics of biological processes into account. Unfortunately, this model is not tractable, so we will use a Monte Carlo simulation method in order to approximate the multidimensional random variables involved. The main strength of our approach is its ability to model generic biological and socio-economic dynamic processes, which are both explicitly spatial and stochastic. …

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Introducing River Modelling In The Implementation Of The Dpsir Scheme Of The Water Framework Directive, Stefano Marsili-Libelli, Francesco Betti, Susanna Cavalieri Jul 2004

Introducing River Modelling In The Implementation Of The Dpsir Scheme Of The Water Framework Directive, Stefano Marsili-Libelli, Francesco Betti, Susanna Cavalieri

International Congress on Environmental Modelling and Software

In Italy the National Environmental Protection Agency (ANPA) is about to adopt the Drivers- Pressures-States-Impacts-Responses (DPSIR) model introduced by the EC Water Framework Directive (WFD). This paper reassess the current definitions of Indicators in the light of the WFD, proposes the design of modular procedures and computational practices to determine the most significant State indicators, integrates the QUAL2E water quality model for the generation of quality data to assess differing DPSIR scenarios, with the final aim to produce an integrated software, partly based on Excel and partly on QUAL2E, whereby current quality data can be used to generate quality scenarios …

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