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An Agglomeration Payment For Cost-Effective Biodiversity Conservation In Spatially Structured Landscapes, Martin Drechsler, Frank Wätzold, Karin Johst, Jason F. Shogren Jul 2010

An Agglomeration Payment For Cost-Effective Biodiversity Conservation In Spatially Structured Landscapes, Martin Drechsler, Frank Wätzold, Karin Johst, Jason F. Shogren

International Congress on Environmental Modelling and Software

Connected habitats are ecologically more valuable than isolated habitats for many species. A key challenge when designing payments for biodiversity in fragmented landscapes is to increase the spatial connectivity of habitats. Based on the idea of an agglomeration bonus we consider a scheme in which land-owners only receive payments if habitats are arranged in an ecologically favourable configuration. We compare the costeffectiveness of agglomeration payments to spatially homogeneous payments on a conceptual level. Our results suggest that positive efficiency gains exist for agglomeration payments. We use Large Blue butterfly habitat in Germany as a specific case study, and find the …

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Modelling Connectivity Between Pollutant Source Areas And Streams, S. Moshirvaziri, G. Sheridan, Patrick N. J. Lane, O. Jones Jul 2010

Modelling Connectivity Between Pollutant Source Areas And Streams, S. Moshirvaziri, G. Sheridan, Patrick N. J. Lane, O. Jones

International Congress on Environmental Modelling and Software

The nature of pollutant connectivity between unsealed forest roads and adjacent nearby streams is examined numerically in terms of spatial and temporal patterns of runoff generation, erosion, and sediment transport. In this paper we consider the relative effects of rainfall intensity and duration, surface roughness, infiltration rate, macropore flow and sediment detachment and transport. The objective of the numerical simulation of this hillslope system is to identify the dominant processes and parameters that affect the degree of pollutant connectivity between roads and streams. The St. Venant equations are applied to extract a two-dimensional diffusion wave model with variable conductivity and …

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Unexpected Side-Effects Of Winter Feeding: Learning From Mahalanobis Distances Factor Analysis In The Case Of Red-Crowned Cranes In Hokkaido, Japan, Yi-Liang Kuo Jul 2010

Unexpected Side-Effects Of Winter Feeding: Learning From Mahalanobis Distances Factor Analysis In The Case Of Red-Crowned Cranes In Hokkaido, Japan, Yi-Liang Kuo

International Congress on Environmental Modelling and Software

Winter feeding has become a critical approach to sustain animals in high latitude,but little literature has investigated possible side-effects in terms of ecological niches. Toexplore whether winter feeding might affect species distributions at regional scale, weemployed a novel spatial model, Mahalanobis Distances Factor Analysis, in the case ofRed-crowned Cranes (Grus japonensis) in Hokkaido, Japan. This model features betterprediction ability with more explicit ecological significance compared to conventionalmethods. Furthermore, particularly innovative is that axes are used to define ecologicalniches, with a minimal set of habitual variables to calculate habitat suitability in thealgorithm. In results, winter feeding seemed to considerably impact the …

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Evolving Gesconda To An Intelligent Decision Support Tool, Miquel Sànchez-Marrè, Karina Gibert, Beatriz Sevilla Jul 2010

Evolving Gesconda To An Intelligent Decision Support Tool, Miquel Sànchez-Marrè, Karina Gibert, Beatriz Sevilla

International Congress on Environmental Modelling and Software

In this work, the GESCONDA system is presented. Initially it was conceived as a system for knowledge discovery and Data Mining, but currently, the system supports two new functionalities. A case-based reasoning engine and a rule-based reasoning shell are provided. These new skills of GESCONDA makes it a suitable prototype tool for the deployment of Intelligent Decision Support Systems, including all main steps like data preparation and filtering, data mining, model validation, reasoning abilities to generate solutions, and predictive models to support final users. The purpose of the paper is to present its architecture as well as its functionalities.

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Mapping, Modelling And Managing Ecosystems Services In New Zealand, Daniel T. Rutledge, John Dymond, Suzie Greenhalgh, Anne-Gaelle Ausseil, Robyn Sinclair, Alexander Herzig, Fraser Morgan, Robbie Andrew, Alison Collins Jul 2010

Mapping, Modelling And Managing Ecosystems Services In New Zealand, Daniel T. Rutledge, John Dymond, Suzie Greenhalgh, Anne-Gaelle Ausseil, Robyn Sinclair, Alexander Herzig, Fraser Morgan, Robbie Andrew, Alison Collins

International Congress on Environmental Modelling and Software

Central and local government agencies in New Zealand are calling for a paradigm shift in natural resource management. A unified approach is required to deliver a wide range of services and outcomes in a sustainable manner. Our new, 4-year research project aims to provide the scientific basis for such an approach. We are taking a threephase approach. First, we will characterize, classify and quantitatively map past and current state of a comprehensive suite of ecosystem services nationally. We will use a tiered approach that reflects the level of knowledge available about various services. Second, we will explore how future changes …

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New Software Methods In Radar Ornithology Using Wsr-88d Weather Data And Potential Application To Monitoring Effects Of Climate Change On Bird Migration, Reginald Mead, John Paxton, Richard S. Sojda Jul 2010

New Software Methods In Radar Ornithology Using Wsr-88d Weather Data And Potential Application To Monitoring Effects Of Climate Change On Bird Migration, Reginald Mead, John Paxton, Richard S. Sojda

International Congress on Environmental Modelling and Software

Radar ornithology has provided tools for studying the movement of birds,especially related to migration. Researchers have presented qualitative evidence suggestingthat birds, or at least migration events, can be identified using large broad scale radars suchas the WSR-88D used in the NEXRAD weather surveillance system. This is potentially aboon for ornithologists because such data cover a large portion of the United States, areconstantly being produced, are freely available, and have been archived since the early1990s. A major obstacle to this research, however, has been that identifying birds inNEXRAD data has required a trained technician to manually inspect a graphically renderedradar sweep. …

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Quantifying Ecosystem Service Trade-Offs, Sven Lautenbach, Martin Volk, Bernd Gruber, Carsten F. Dormann Jul 2010

Quantifying Ecosystem Service Trade-Offs, Sven Lautenbach, Martin Volk, Bernd Gruber, Carsten F. Dormann

International Congress on Environmental Modelling and Software

The ecosystem services concept evaluates ecosystem functions from a human perspective, e.g. the concept focuses on the contribution of ecosystem functions, ecosystem goods and services or human well-being. An evaluation allows the analysis of trade-offs between different ecosystem services as well as between ecosystem services and other components of human well-being. We will test three options to compare trade-offs between ecosystem services, namely map comparison, scenario analysis and trade-off analysis using optimized landscapes. While map comparison and scenario analysis are valuable tools to study ecosystem service trade-offs we emphasize the use of optimized landscapes for tradeoff analysis. Overall, analysis of …

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Numerical Modeling Of The Salinity Distribution And Environmental Flows Assessment In The Yellow River Estuary, China, T. Sun, Z. F. Yang Jul 2010

Numerical Modeling Of The Salinity Distribution And Environmental Flows Assessment In The Yellow River Estuary, China, T. Sun, Z. F. Yang

International Congress on Environmental Modelling and Software

Predication of environmental flows is a critical issue in water resourcesmanagement integrated with ecological considerations. It is also a complex issue due to therelationship between ecological and hydrological processes with different temporal andspatial scales in estuarine ecosystems. The salinity gradient is a basic characteristic for anestuary ecosystem, which is largely affected by the alteration of freshwater inflows becauseof human activities. In this paper, a numerical model was developed for simulating thesalinity distribution under the action of river discharge and tide current in the Yellow RiverEstuary. Environmental flow requirements were determined for critical periods in theYellow River Estuary after identifying the …

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Modelling Human Health By Levels Of Biological Organization, Wilfred R. Cuff, Clifford Clark, Paulette Richard, Venkata R S K Duvvuri Jul 2010

Modelling Human Health By Levels Of Biological Organization, Wilfred R. Cuff, Clifford Clark, Paulette Richard, Venkata R S K Duvvuri

International Congress on Environmental Modelling and Software

The hierarchy of levels in the organization of matter, or the “hierarchy of life”, is a fundamentalconcept in biology, and biologists are used to thinking about their work asbeing at a particular level. Yet medicine, in both research and application, operatessomewhat independently of this concept, working almost exclusively at levels at or belowthe individual. Through the relatively-recent expansion of epidemiology, medicinedoes reach up to the level of the population - but medicine at higher levels of biologicalorganization remains under-developed. In this paper we review the biological idea ofhierarchy of life and explore what medical research and practice might look like …

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Effective Microorganisms (Em) Technology For Water Quality Restoration And Potential For Sustainable Water Resources And Management, Zuraini Zakaria, Sanjay Gairola, Noresah Mohd Shariff Jul 2010

Effective Microorganisms (Em) Technology For Water Quality Restoration And Potential For Sustainable Water Resources And Management, Zuraini Zakaria, Sanjay Gairola, Noresah Mohd Shariff

International Congress on Environmental Modelling and Software

Water quality has received considerable attention in allocation processes formaximizing the satisfaction of various sectors. However, pollutant impurities that impedeadequate supply of water have a detrimental effect on the quality and harmful for livingorganisms including aquatic life. For the reduction of water pollution level, variouschemical and biological treatments are available but the emergence of an amazingtechnology of a multiculture of anaerobic and aerobic beneficial microorganisms ispresently gaining popularity due to its environmentally friendly nature. This effectivemicroorganism (EM) technology uses naturally occurring microorganisms which are ableto purify and revive nature. Applications of EM using the formula known as effectivemicroorganism activated solution …

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The Application Of A Validated Hydrodynamic Model To Improve The Water Management Of An Egyptian Shallow Water Coastal Lake, M. A. Bek, I. S. Lowndes, D. M. Hargreaves Jul 2010

The Application Of A Validated Hydrodynamic Model To Improve The Water Management Of An Egyptian Shallow Water Coastal Lake, M. A. Bek, I. S. Lowndes, D. M. Hargreaves

International Congress on Environmental Modelling and Software

This paper presents the preliminary results of the application of the ocean model (FVCOM)to replicate the hydrodynamic flows experienced within Lake El-Manzala, Egypt. Theconstruction of this model is used to characterize the ecosystem of this shallow brackishlake and assess a range of sustainable water management strategies. Lake El-Manzala is thelargest of the Egyptian shallow coastal lakes on the fringe of the Mediterranean Sea. Thelake currently supports 30% of the fresh water fish farm production of Egypt. In recentyears the aquatic health of the lake has significantly deteriorated due to an increase in thecontamination of the lake by polluted inflows and …

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What Can We Learn From Systems Based Approaches: From Systems Biology To Earth Systems Science?, C. J. A. Macleod Jul 2010

What Can We Learn From Systems Based Approaches: From Systems Biology To Earth Systems Science?, C. J. A. Macleod

International Congress on Environmental Modelling and Software

Systems based approaches have been developed and applied in a broad range ofdisciplines. These cover a wide range of processes, structures and scales. Ludwig vonBertalanffy is often credited with establishing and developing ‘general systems theory’.The ecosystem based approach to ecology developed by the Odum brothers (EugenePleasants and Howard Thomas) instigated approaches to understanding ecological systemsthat are still advancing within the frameworks of ecosystem services and ecologicalthermodynamics. West Churchman and Russel Ackoff were early pioneers in the field ofoperations research following on from techniques developed during the Second WorldWar. Jay Forrester was also influenced by his work on feedback systems during …

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Dust Storms Over The Arabian Gulf: An Optimistic Vision Toward Climate Change Consequences, Waleed Hamza, Mohamed Rizk, Huda Al-Hassini, Jan Stuut, Dirk De-Beer Jul 2010

Dust Storms Over The Arabian Gulf: An Optimistic Vision Toward Climate Change Consequences, Waleed Hamza, Mohamed Rizk, Huda Al-Hassini, Jan Stuut, Dirk De-Beer

International Congress on Environmental Modelling and Software

Dust storms frequencies and strengths have been monitored during 2009 at different locations along the coastal areas of the United Arab Emirates as a representative site of the Arabian Gulf marine environment. The results have been compared with the previous five years data set. Moreover mineralogical components of the collected dust samples during the study period have been analyzed using both XRD and XRF techniques. The results of comparison have allowed to evaluate changes occurred in dust storms characteristics over the Arabian Gulf and to consider it as a sensitive signal of climate changes over the region. It has been …

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Formalizing Knowledge On International Environmental Regimes For Integrated Assessment Modeling, M. De Vos, P. Janssen, S. Frantzi, P. Pattberg, A. Petersen, F. Biermann, M. Kok Jul 2010

Formalizing Knowledge On International Environmental Regimes For Integrated Assessment Modeling, M. De Vos, P. Janssen, S. Frantzi, P. Pattberg, A. Petersen, F. Biermann, M. Kok

International Congress on Environmental Modelling and Software

International environmental regimes are considered key factors in dealing with global environmental problems. It is important to understand if and how these regimes are effective in solving or improving global environmental problems. In this paper we present a multidisciplinary approach to formalize knowledge on the effectiveness of environmental regimes. We constructed a conceptual framework to enhance systematic analysis of conditions that influence regime effectiveness and implemented this into a computer model using fuzzy logic reasoning. We applied the model in a preliminary analysis of two environmental regimes, the Convention on Biological Diversity and the United Nations Framework Convention on Climate …

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Impacts Of Environmental Factors And Shellfish Practices On The Mont-St-Michel Bay Ecosystem (France). A Modelling Study Involving Scientists And Local Stakeholders., Philippe Cugier, Caroline Struski, Karine Grangere, Michel Blanchard, Katia Frangoudès, Thierry Robin, José Pérez, Rémi Mongruel, Joseph Mazurié, Patrick Le Mao, Guy Fontenelle Jul 2010

Impacts Of Environmental Factors And Shellfish Practices On The Mont-St-Michel Bay Ecosystem (France). A Modelling Study Involving Scientists And Local Stakeholders., Philippe Cugier, Caroline Struski, Karine Grangere, Michel Blanchard, Katia Frangoudès, Thierry Robin, José Pérez, Rémi Mongruel, Joseph Mazurié, Patrick Le Mao, Guy Fontenelle

International Congress on Environmental Modelling and Software

The macro-benthic communities of Mont-Saint-Michel Bay, located in the Norman-Breton Gulf (English Channel) along the French coast, are mainly dominated by filter-feeders which include cultivated species (oysters and mussels). The decline in shellfish farms production and the significant spreading of the invasive slipper-limpet Crepidula fornicata have conducted scientists and stakeholders to undertake a reflexion on the trophic balance between cultivated and wild (native or invasive non-native) filterfeeders. An ecological model of the bay was developed, coupling a 2D hydro-sedimentary model along with biological models for primary production and filter-feeder growth. The objectives of the project were first to provide indicators …

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Set-Membership Approach For Identification Of The Uncertainty In Power-Law Relationships: The Case Of Sediment Yield, Karel J. Keesman, Lachlan T. H. Newham, Tony Jakeman Jul 2010

Set-Membership Approach For Identification Of The Uncertainty In Power-Law Relationships: The Case Of Sediment Yield, Karel J. Keesman, Lachlan T. H. Newham, Tony Jakeman

International Congress on Environmental Modelling and Software

Power laws are used to describe a large variety of natural and man-made phenomena. Consequently, they are used in a wide range of scientific research and management applications. In this paper, we focus on the identification of uncertainty bounds on a power law relationship from experimental data, using a bounded-error characterization. These bounds can subsequently be used as constraints in e.g. optimization and scenario studies. The basic so-called set-membership approach involves outlier identification and removal, feasible parameter set estimation, evaluation of the feasible model output set and tuning of the error bounds. As an example we examine scattered sediment yield …

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Empathy: A Unifying Approach To Address The Dilemma Of 'Environment Versus Economy', A. Guergachi, O. Ngenyama, V. Magness, J. Hakim Jul 2010

Empathy: A Unifying Approach To Address The Dilemma Of 'Environment Versus Economy', A. Guergachi, O. Ngenyama, V. Magness, J. Hakim

International Congress on Environmental Modelling and Software

When environmentalists warned, back in the 1970s, against pesticides andfertilizers, the then United States Secretary of Agriculture retorted that “before we go backto organic agriculture, somebody is going to have to decide what 50 million people we aregoing to let starve”. This exchange is nothing but an illustration of the dilemmatic choicethat societies in general have been asked to make: “develop the economy” or “protect theenvironment”. This paper proposes an integrated framework to resolve the dilemma of'environment versus economy'. This framework unfolds the essential characteristics ofsustainable societies and outlines the mechanics that underlie sustainable development.Referred to as ‘General Theory of …

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Development And Validation Of A Decision Support System For The Integrated Operation Of Membrane Bioreactors, Joaquim Comas, Hèctor Monclús, Giuliana Ferrero, Ignasi Rodríguez-Roda, Luis Sancho, Eduardo Ayesa Jul 2010

Development And Validation Of A Decision Support System For The Integrated Operation Of Membrane Bioreactors, Joaquim Comas, Hèctor Monclús, Giuliana Ferrero, Ignasi Rodríguez-Roda, Luis Sancho, Eduardo Ayesa

International Congress on Environmental Modelling and Software

Membrane bioreactor technology in wastewater treatment and re-use is currently challenging traditional wastewater methods. However, although this technology presents many advantages as in most membrane filtration processes the permeate flux and permeability declines during filtration due to membrane fouling. Therefore controlling membrane fouling is the key issue in MBR operation. Nevertheless, membrane fouling is a very complicated phenomenon that results from multiple causes. Thus an intelligent Decision Support System for the integrated operation of membrane bioreactors has been developed. This Decision Support System, based on empiric and heuristic knowledge, gathers on-line and off-line information about both the biological and physical …

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A Modelling Platform For Complex Socioecosystems: An Application To Freshwater Management In Coastal Zones, Johanna Ballé-Béganton, M. Lample, Cédric Bacher, A. Fiandrino, V. Guillard, T. Laugier, Rémi Mongruel, J. A. Pérez Agúndez Jul 2010

A Modelling Platform For Complex Socioecosystems: An Application To Freshwater Management In Coastal Zones, Johanna Ballé-Béganton, M. Lample, Cédric Bacher, A. Fiandrino, V. Guillard, T. Laugier, Rémi Mongruel, J. A. Pérez Agúndez

International Congress on Environmental Modelling and Software

Providing deliberation support tools for freshwater management in coastal zones requires complex socio-ecosystem modelling in a joint effort from research scientists, software engineers and stakeholders. The SPICOSA System Approach Framework provides guidelines for the building of dynamic models for a better comprehension of the variety of processes and issues regarding coastal management. A modular platform was developed using the ExtendSim® software. We explore how the SPICOSA/Extend platform supports participatory modelling by offering the necessary tools for the integration of multidisciplinary knowledge and how the use of a common platform facilitates dialog between research scientists of varied backgrounds. Graphical tools developed …

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Informing Regional Planning In Alberta’S Oilsands Region With A Land-Use Simulation Model, Matthew Carlson, Terry Antoniuk, Dan Farr, Shawn Francis, Karen Manuel, John Nishi, Brad Stelfox, Mika Sutherland, Cornel Yarmoloy, Craig Aumann Jul 2010

Informing Regional Planning In Alberta’S Oilsands Region With A Land-Use Simulation Model, Matthew Carlson, Terry Antoniuk, Dan Farr, Shawn Francis, Karen Manuel, John Nishi, Brad Stelfox, Mika Sutherland, Cornel Yarmoloy, Craig Aumann

International Congress on Environmental Modelling and Software

Planning for regional sustainability requires strategic understanding of ecological and socioeconomic trade-offs associated with alternative land use options. We discuss a scenario analysis being undertaken to assess trade-offs for a 93,000 km2 region in northeastern Alberta containing the world’s second largest oil deposit. Due to its immense economic and ecological value, the region presents both an opportunity and challenge for the objectives of sustainable prosperity and healthy ecosystems put forth by the Alberta government’s Land-Use Framework. ALCES® simulation and mapping software are being applied to inform government planners and stakeholders about possible future outcomes associated with land-use options. Two characteristics …

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A Scientific Workflow Tool For Biosphere Modelling: Carbon Sink Archives, G. A. Alexandrov, T. Matsunaga Jul 2010

A Scientific Workflow Tool For Biosphere Modelling: Carbon Sink Archives, G. A. Alexandrov, T. Matsunaga

International Congress on Environmental Modelling and Software

Scientific workflows in the field of biosphere modelling include assessment of the state of the art in modelling global biogeochemical cycles. The process of assessment consists of the following steps: collecting model outputs, performing model inter-comparison study, writing summary for policymakers, formulating an agenda for further research. Here, we present a web-based service that automates the entire process.

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Modelling Urban Land Use Change Using Geographically Weighted Regression And The Implications For Sustainable Environmental Planning, Noresah Mohd Shariff, Sanjay Gairola, Anita Talib Jul 2010

Modelling Urban Land Use Change Using Geographically Weighted Regression And The Implications For Sustainable Environmental Planning, Noresah Mohd Shariff, Sanjay Gairola, Anita Talib

International Congress on Environmental Modelling and Software

In this study we applied Geographically Weighted Regression (GWR) approach to model urban landuse changes in Penang Island from 1990 to 2005, covering the period during which the Island has experiencedtremendous urban growth due to in migration from adjacent areas. Land use change has potential impacts on thephysical and social environment. We identified spatial variables describing environment, physical and socioeconomicfactors which are hypothesized to influence the change in the land use in the study area. An ordinaryleast squares regression (OLS) model is applied to the variables followed by a GWR model and the results arecompared. The results show that the …

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Pitimbu River Lowland Portion Water And Sediment Monitoring Data, Natal Brazil, Rafael Takeshi Kobayashi, Lúcio Flávio Ferreira Moreira, Herbert Tadeu De Almeida Andrade Jul 2010

Pitimbu River Lowland Portion Water And Sediment Monitoring Data, Natal Brazil, Rafael Takeshi Kobayashi, Lúcio Flávio Ferreira Moreira, Herbert Tadeu De Almeida Andrade

International Congress on Environmental Modelling and Software

Urbanization in developing countries has had a significant impact on water resources and the environment. Anthropogenic-related factors such as deforestation, uncontrolled urban occupation and the lack of sustainable measures have affected both the quantity and quality of water. The Pitimbu river watershed (126.7 km2) is located within the urban area of Natal, Brazil. The effects of urban occupation have recently been a concern to municipal authorities, since the Pitimbu is the main source of domestic water supply. In this paper authors analyze monitoring data, including the quantitative and qualitative water and sediment factors at the lowland portion of this river …

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Fast Variable Selection For Extreme Values, A. Phatak, C. Chan, H. Kiiveri Jul 2010

Fast Variable Selection For Extreme Values, A. Phatak, C. Chan, H. Kiiveri

International Congress on Environmental Modelling and Software

In this paper, we outline and explore the use of RaVE, a sparse variable selectionmethod that can be used for selecting variables when modelling extreme values. We illustrate itsuse by modelling the location parameter of a series of length 49 of annual rainfall maxima at twostations in North-West Western Australia. The ensemble of potential predictors consists of 1980atmospheric variables. Preliminary results show that RaVE can produce parsimonious yet sensiblemodels. Future work will focus on devising criteria to select the best choice of hyperparametersand on methods to choose groups of spatially contiguous variables so as to aid interpretation.

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Impact Of Land-Use Changes On The Hydrological Processes In The Elbow River Watershed In Southern Alberta, G. N. Wijesekara, A. Gupta, C. Valeo, J. G. Hasbani, Danielle J. Marceau Jul 2010

Impact Of Land-Use Changes On The Hydrological Processes In The Elbow River Watershed In Southern Alberta, G. N. Wijesekara, A. Gupta, C. Valeo, J. G. Hasbani, Danielle J. Marceau

International Congress on Environmental Modelling and Software

Due to the rapid population growth and urbanization in the City of Calgary, the Elbow River watershed in southern Alberta covering 1238 km2 has been subjected to considerable land-use changes over the last decade. The objective of this study is to assess the impact of land-use intensification simulated with a cellular automata (CA) model on the hydrological processes of the watershed using MIKE-SHE, a physically-based and distributed hydrological model. MIKE-SHE was calibrated for the period 1985-1990 and validated for the period 2000-2005. The calibration was achieved by comparing observed and simulated flow data. The CA model was calibrated using four …

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Renyi's-Entropy-Based Approach For Selecting The Significant Input Variables For The Ecological Data, Can-Tao Liu, Bao-Gang Hu Jul 2010

Renyi's-Entropy-Based Approach For Selecting The Significant Input Variables For The Ecological Data, Can-Tao Liu, Bao-Gang Hu

International Congress on Environmental Modelling and Software

Recently, data-driven approaches including machine-learning (ML) techniqueshave played a key role in the research on ecological data and models. One of the mostimportant steps in the application of a ML technique is the selection of significant modelinput variables. Among ML methods, artificial neural networks and genetic algorithm arewidely used for the sake of the above aim; however entropy-based learning methods havenot been well adopted in the field of selecting the significant input variables for ecologicalmodel. In this paper, we utilize Renyi’s entropy to estimate mutual information, and thencompute maximum relevance and minimum redundancy of the input variables by themutual information …

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Modelling The Ecological Impact Of Discharged Urban Waters Upon Receiving Aquatic Ecosystems. A Tropical Lowland River Case Study: City Cali And The Cauca River In Colombia, Gonzalez J. Holguin, Peter L. M. Goethals Jul 2010

Modelling The Ecological Impact Of Discharged Urban Waters Upon Receiving Aquatic Ecosystems. A Tropical Lowland River Case Study: City Cali And The Cauca River In Colombia, Gonzalez J. Holguin, Peter L. M. Goethals

International Congress on Environmental Modelling and Software

The Cauca river is one of most severe cases of pollution for domestic and industrial wastewater discharges in Colombia, principally when it crosses the industrial cities of Cali and Yumbo. The rapid urbanization and major economic development in the Cauca river´s geographical valley has led to dramatic degradation of the environment and increased health risks due to inefficient processing of the increased pollutant load effluents and solid wastes. The city of Cali which is the main urbanization center, with more than two million inhabitants and limitations of the treatment of its wastewaters, discharged in the year 2005, 75 tons of …

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An Interdisciplinary Framework For The Development And Analysis Of Crop Models, Sebastien Roux, Myriam Adam, Wery Jacques Jul 2010

An Interdisciplinary Framework For The Development And Analysis Of Crop Models, Sebastien Roux, Myriam Adam, Wery Jacques

International Congress on Environmental Modelling and Software

Development and use of crop models has become an interdisciplinary field with the increase on one hand of the biophysical knowledge and the development of numerous dedicated software platforms on the other hand. This trend calls for formalizing the integration of the disciplinary contributions of scientists having different expertises needed in crop modelling : agronomists, mathematicians, software scientists. We propose an interdisciplinary framework to : (1) describe the model with different expert domain knowledge, (2) identify bridges to help scientists of different domains to work together on the same model, (3) give a methodological basis (engine) for crop model studies. …

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Modeling Dynamical Temperature Influence On Tick Ixodes Scapularis Population, Xiaotian Wu, Venkata R S K Duvvuri, Jianhong Wu Jul 2010

Modeling Dynamical Temperature Influence On Tick Ixodes Scapularis Population, Xiaotian Wu, Venkata R S K Duvvuri, Jianhong Wu

International Congress on Environmental Modelling and Software

Lyme disease has been recognised as one of the emerging vector borne diseases in Canada. Ticks, Ixodes scapularis SAY, play a major role as vectors of Lyme disease causative agent Borrelia burgdorferi. Ticks become infected with Borrelia while feeding on the primary hosts (mice, squirrels, shrews, and other small vertebrates). Deers are primary source of nourishment for each gravid female I. scapularis and are fundamental to the tick establishment without infection. The life cycle of tick, I. scapularis, is very complex and takes nearly two years to reach adult stage from egg. Studies have shown that tick life cycle is …

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Formalizing Knowledge On International Environmental Regimes For Integrated Assessment Modeling, M. De Vos, P. Janssen, S. Frantzi, P. Pattberg, A. Petersen, F. Biermann, M. Kok Jul 2010

Formalizing Knowledge On International Environmental Regimes For Integrated Assessment Modeling, M. De Vos, P. Janssen, S. Frantzi, P. Pattberg, A. Petersen, F. Biermann, M. Kok

International Congress on Environmental Modelling and Software

International environmental regimes are considered key factors in dealing with global environmental problems. It is important to understand if and how these regimes are effective in solving or improving global environmental problems. In this paper we present a multidisciplinary approach to formalize knowledge on the effectiveness of environmental regimes. We constructed a conceptual framework to enhance systematic analysis of conditions that influence regime effectiveness and implemented this into a computer model using fuzzy logic reasoning. We applied the model in a preliminary analysis of two environmental regimes, the Convention on Biological Diversity and the United Nations Framework Convention on Climate …

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