Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

2010

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 5311 - 5340 of 18896

Full-Text Articles in Entire DC Network

Validation And Sensitivity Analysis Of Catchment Runoff And Erosion Simulation Technology (Crest): A Gis-Assisted Soil Erosion Model At Watershed Level, Reynaldo L. Lanuza, Eduardo P. Paningbatan Jr Jul 2010

Validation And Sensitivity Analysis Of Catchment Runoff And Erosion Simulation Technology (Crest): A Gis-Assisted Soil Erosion Model At Watershed Level, Reynaldo L. Lanuza, Eduardo P. Paningbatan Jr

International Congress on Environmental Modelling and Software

Most erosion models have been developed based on a plot scale and have limited application to a watershed due to the differences in scale. In order to address this limitation, a GIS-assisted methodology for modeling soil erosion was developed using PCRaster to predict the rate of soil erosion at watershed level and identify the location of erosion prone areas. The GIS-assisted hydrology and erosion models were validated at Tanghaga Watershed using the observed values from previous experiment. The predicted peak rates, Qp, showed a highly significant relationship with the observed Qp, with an r2 value of 0.75. For soil loss …

Go to article

Integrated Meta-Modelling For Decision Support In Integrated Catchment Management, Vikas Kumar, A. Holzkämper, D. N. Lerner Jul 2010

Integrated Meta-Modelling For Decision Support In Integrated Catchment Management, Vikas Kumar, A. Holzkämper, D. N. Lerner

International Congress on Environmental Modelling and Software

Developing supporting models for multidisciplinary, uncertain and complex Integrated Catchment Management (ICM) is a highly challenging task. Knowledge from multiple disciplines must be integrated, and the process is compounded by significant uncertainty. The key gap that provides the research context is the need for a holistic modelling framework to support ICM, able to capture system complexities and interrelationships, and identify long-term solutions to catchment management problems. In this paper, we present the feasibility study of a new framework for developing an integrated meta-model for decision-support in ICM. The study undertaken by the Catchment Science Centre at the University of Sheffield …

Go to article

Development Of A Land-Use Component For An Integrated Model Of The German Biogas System, A. Schaldach, D. Lapola, U. Jessen, M. Thees, Ruediger Schaldach Jul 2010

Development Of A Land-Use Component For An Integrated Model Of The German Biogas System, A. Schaldach, D. Lapola, U. Jessen, M. Thees, Ruediger Schaldach

International Congress on Environmental Modelling and Software

Germany is one of the biggest producers of biogas in Europe. Biogas can either be combusted in highly efficient combined heat and power units to produce electricity and heat, or upgraded to biomethane for injection into the natural gas grid. As political conditions encourage the installation of new biogas plants, their number and capacity is expected to grow significantly in the next few years. In Germany, energy crops play an important role for biogas production. Due to their relatively low energy content transport distances from the field to the plants are a crucial issue for the efficiency of the biogas …

Go to article

Agent Based Modelling Of Caribou Environmental Interactions In The Canadian Arctic, Glen Lesins, Kaz Higuchi Jul 2010

Agent Based Modelling Of Caribou Environmental Interactions In The Canadian Arctic, Glen Lesins, Kaz Higuchi

International Congress on Environmental Modelling and Software

Agent or individual based modelling (IBM) is recognized as an important tool in biological modelling for simulating animal behaviour and interactions with the environment at the level of the individual while maintaining a collective perspective. The method allows rules to be programmed for the interactions between like and unlike species, responses to geographic factors and impacts from human activities. By emphasizing the development of appropriate rules for the individual, one can avoid imposing ad hoc assumptions concerning the population as a whole and instead allow emergent phenomena to unfold at the larger scale. Here we report on preliminary results using …

Go to article

Mr Potatohead Framework – A Software Tool For Collaborative Land-Use Change Modeling, Mike Livermore Jul 2010

Mr Potatohead Framework – A Software Tool For Collaborative Land-Use Change Modeling, Mike Livermore

International Congress on Environmental Modelling and Software

Agent-based land-use cover/change models (ABM/LUCC), which can be used for various types of complex human-environment interactions, recently have been gaining popularity. ABM/LUCC models combine a spatial representation of the landscape with key decision-makers (e.g. farmers and institutions) and an environment for interaction. There is inherent complexity in modeling human-environment interactions which need to be assessed at multiple spatial and time scales, and often multiple models are integrated; however, current methods of developing integrated models are often cumbersome and communicating design and results can be a great challenge and would be aided by a common framework in which different models can …

Go to article

Evaluation Of The Changed Properties Of Aquatic Animals After Dam Construction Using Ecological Network Analysis, Chen Shaoqing, Liao Xueqin, Yang Jin, Chen Bin Jul 2010

Evaluation Of The Changed Properties Of Aquatic Animals After Dam Construction Using Ecological Network Analysis, Chen Shaoqing, Liao Xueqin, Yang Jin, Chen Bin

International Congress on Environmental Modelling and Software

Dam construction results in variations of hydrology, river morphology and habitat and thebiota associated with the reservoir change significantly compared to the assemblage before damconstruction in order to match these changed environmental conditions. Some attempts so far havebeen made to ascertain the changed properties of aquatilia due to dam construction. Most of them,however, were focused on perturbances to single factors, such as rearing habitats, reproduction andmigration routes, etc. Few have been done on the performance of aquatilia from the whole-ecosystemperspective. Herein, we evaluate the structural properties of aquatic animals and their complexecological relationships within the ecosystem before and after dam …

Go to article

Development Of A Modular Environmental Decision Support System For The Integrated Management Of The Urban Wastewater Cycle At River Basin Scale, D. Murlà, A. Monistrol, Manel Poch, D. Sunyer Jul 2010

Development Of A Modular Environmental Decision Support System For The Integrated Management Of The Urban Wastewater Cycle At River Basin Scale, D. Murlà, A. Monistrol, Manel Poch, D. Sunyer

International Congress on Environmental Modelling and Software

Most of Urban Wastewater Systems (UWS) have been managed separately, without considering any interaction between sewer systems, Wastewater Treatment Plants (WWTPs) and the receiving waters. Nowadays, the conventional practice has changed, introducing the integrated management concept into the river basin scale. The goal of the project is to develop a modular Environmental Decision Support System (EDSS) to optimise the integrated management of the UWS based on a rule based system as the reasoning core and a Knowledge Base, easily represented by means of decision trees and fully opened. The EDSS, based upon expert knowledge and simulation results, will allow proposing …

Go to article

Feedbacks In Socio-Environmental Land Systems, Joerg A. Priess, Nina Schwarz, Sven Lautenbach Jul 2010

Feedbacks In Socio-Environmental Land Systems, Joerg A. Priess, Nina Schwarz, Sven Lautenbach

International Congress on Environmental Modelling and Software

The dynamics of socio-environmental systems are driven by exogenous forcesand by the interaction of endogenous system components, both within the social and environmentalrealms, as well as between them. In recent years, the number of models andmodelling frameworks explicitly representing feedbacks has increased, especially for modelsof land use systems. Land use changes are on the one hand caused by a complex interactionof human and/or institutional land use demands and the environment, which supportsor limits human use in several aspects. On the other hand, land use changes and theireffects at least partly influence the respective driving forces and future land-use decisions,e.g. by …

Go to article

Spatio-Temporal Modelling Of The Spread Of Common Reed On The Finnish Coast, Anas Altartouri, Ari Jolma, Päivi Korpinen Jul 2010

Spatio-Temporal Modelling Of The Spread Of Common Reed On The Finnish Coast, Anas Altartouri, Ari Jolma, Päivi Korpinen

International Congress on Environmental Modelling and Software

The common reed (Phragmites Australis) has overtaken the Finnish coast of theGulf of Finland in many places influencing the coastal ecology and reducing therecreational value of the coast. Our research aims at developing a spatio-temporalsimulation model of the spread of reed. In order to account for the dynamic nature of thespread, a cellular automata model is employed. We investigate in depth the explanatoryvariables and their relevance to the phenomenon. It was found that water depth, proximityto river mouths, and sea openness are significant explanatory variables of the phenomenon.A predictive logistic regression model is suggested to aggregate the explanatory variablesand provide …

Go to article

Reasoning About Actions For The Management Of Urban Wastewater Systems Using A Causal Logic, Dario Garcia-Gasull, Juan Carlos Nieves, Ulises Cortés Jul 2010

Reasoning About Actions For The Management Of Urban Wastewater Systems Using A Causal Logic, Dario Garcia-Gasull, Juan Carlos Nieves, Ulises Cortés

International Congress on Environmental Modelling and Software

The management of Urban Wastewater Systems (UWS) is a critical and difficult process. Handling polluted water in UWS requires planning and decision making regarding sectors such as environmental, energetic, industrial, etc. In order to represent all the significant concepts, a powerful and flexible formalism is needed. Nowadays, there are solid approaches based on nonmonotonic reasoning which can capture dynamic domains such UWS. In this paper, we present an implementation of a real UWS in the action language Causal Calculator (CCalc-C+) which displays all the singularities of such domain and within which complex queries can be performed. The nonmonotonic causal theory, …

Go to article

Bio-Economic Effects Of Water Shortages On Shellfish Farming. An Integrated Dynamic Modelling Approach, J. A. Pérez Agúndez, Johanna Ballé-Béganton, Rémi Mongruel, Cédric Bacher, O. Le Moine, P. Soletchnik, S. Robert, S. Guesdon Jul 2010

Bio-Economic Effects Of Water Shortages On Shellfish Farming. An Integrated Dynamic Modelling Approach, J. A. Pérez Agúndez, Johanna Ballé-Béganton, Rémi Mongruel, Cédric Bacher, O. Le Moine, P. Soletchnik, S. Robert, S. Guesdon

International Congress on Environmental Modelling and Software

The land-sea interfaces are geographical areas rich in ecosystemic services. However, the increase of anthropogenic pressures is frequently the factor explaining environmental damages phenomena and generating many use conflicts. The integrated coastal zones management has been acknowledged by the different environment international conferences as a sustainability framework. Integration is the key concept on which must be based the reformulation of scientific knowledge required for supporting sustainable governance. That directly questions on the pertinent methods and tools to build for contributing to those decision making processes. This paper explores these topics by focusing on the example of the fresh water share …

Go to article

A Comparison Of Fuzzy, Bayesian And Weighted Average Formulations Of An In-Stream Habitat Suitability Model., C. J. Brookes, Vikas Kumar, S. N. Lane Jul 2010

A Comparison Of Fuzzy, Bayesian And Weighted Average Formulations Of An In-Stream Habitat Suitability Model., C. J. Brookes, Vikas Kumar, S. N. Lane

International Congress on Environmental Modelling and Software

Three variations of a simple in-stream habitat suitability model were implementedand the effect on output for one organism at 22 sites on one short section of a river wasexamined. The model uses only two factors, depth and velocity, to calculate quality and a thirdfactor, width to quantify utility. The implementations were based on 3 multi-criteria evaluationapproaches: Weighted Average, Fuzzy Sets and Bayesian probability. There was broadagreement between the formulations but important differences in detail. The model outputsindicate that uncertainty arising from model formulation is significant and can have a bearingon planning decisions. There is a complex interaction between the formulations …

Go to article

Application Of Life Cycle Analysis (Lca) In Evaluating Energy-Consuming Of Integrated Oxidation Ditch (Iod), Xianchun Tan, Junyi Xu, Sheng Wang, C. Y. Miao Jul 2010

Application Of Life Cycle Analysis (Lca) In Evaluating Energy-Consuming Of Integrated Oxidation Ditch (Iod), Xianchun Tan, Junyi Xu, Sheng Wang, C. Y. Miao

International Congress on Environmental Modelling and Software

With the research on some critical technology going deeply, the problem of technology route and project approach for the saving energy and reducing consumption have become the focus of municipal wastewater treatment process. In this article, LCA (Life Cycle Analysis) is applied to identify and compare the energy consumption of each stage of different technologies in municipal wastewater treatment from the view of whole process. This is carried out after reviewing the condition of energy utilizing of typical technologies in China. And some measures are brought forward to improve the efficiency of energy utilizing. Integrated Oxidation Ditch (IOD) is taken …

Go to article

Exploring Forest Management Practices Using An Agent-Based Model Of Forest Insect Infestations, Liliana Pérez, Suzana Dragicevic Jul 2010

Exploring Forest Management Practices Using An Agent-Based Model Of Forest Insect Infestations, Liliana Pérez, Suzana Dragicevic

International Congress on Environmental Modelling and Software

The forests of British Columbia, Canada have undergone an unprecedented Mountain Pine Beetle, Dendroctonus ponderosae Hopkins, (MPB) infestation that has resulted in extensive mortality of lodgepole pine, Pinus contorta. The objective of this study is to apply the agent-based model (ABM) to simulate the MPB attack behaviour in order to evaluate how different harvesting policies influence spatial characteristics of the forest and spatial propagation of the MPB infestation over time. The first scenario is the no management action with the natural disturbance process leading the changes of the forest ecosystem. The other two scenarios implement sanitation and salvage harvesting methods. …

Go to article

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 …

Go to article

Dynamics Of Habitat Banking Under Changing Conservation Costs And Habitat Restoration Time Lags, Martin Drechsler, Florian Hartig Jul 2010

Dynamics Of Habitat Banking Under Changing Conservation Costs And Habitat Restoration Time Lags, Martin Drechsler, Florian Hartig

International Congress on Environmental Modelling and Software

Tradable permits are a popular instrument for environmental policy. Classical examples are emission control, but tradable permit systems are recently also promoted and applied to the conservation of biodiversity. This raises a number of challenges. One problem is that habitat turnover (the destruction of habitats and restoration elsewhere) is harmful to many species, even if the total amount of habitat is constant. Another problem is that the restoration of habitats often takes time, leading to time lags between the beginning of restoration activities and the time when the restored habitat is available for trading. It is therefore important to understand …

Go to article

Providing Intelligent Decision Support Systems With Flexible Data-Intensive Case-Based Reasoning, Beatriz Sevilla Villanueva, Miquel Sànchez-Marrè Jul 2010

Providing Intelligent Decision Support Systems With Flexible Data-Intensive Case-Based Reasoning, Beatriz Sevilla Villanueva, Miquel Sànchez-Marrè

International Congress on Environmental Modelling and Software

In this paper we present a flexible CBR shell for Data-Intensive Case-Based Reasoning Systems which is fully integrated in an Intelligent Data Analysis Tool entitled GESCONDA. The main subgoal of the developed tool is to create a CBR Shell where no fixed domain exists and where letting the expert/user creates (models) his/her own domain. From an abstract point of view, the definition of the CBR can be seen as a methodology composed by four phases and each phase offers different ways to be solved. Then, since the CBR shell is integrated in GESCONDA, it inherits all its functionalities which cover …

Go to article

Sustainable Forest Management For Bioenergy, Giulia Fiorese, Giorgio Guariso Jul 2010

Sustainable Forest Management For Bioenergy, Giulia Fiorese, Giorgio Guariso

International Congress on Environmental Modelling and Software

Biomass from the forest sector can be an important source of renewable energy and can contribute to climate change mitigation and bioenergy development. However, the removal of biomass from forests can have significant impacts on the forest ecosystems and therefore requires a thorough analysis. The purpose of this work is to compare different alternatives of sustainable forest management with the aim of minimizing greenhouse gases emission. The model used for the analysis, CO2FIX, describes the flows of carbon per unit area of biomass, soil storage and bioenergy products. The model was applied to the forests of the Italian region of …

Go to article

Validation And Sensitivity Analysis Of Catchment Runoff And Erosion Simulation Technology (Crest): A Gis-Assisted Soil Erosion Model At Watershed Level, Reynaldo L. Lanuza, Eduardo P. Paningbatan Jr Jul 2010

Validation And Sensitivity Analysis Of Catchment Runoff And Erosion Simulation Technology (Crest): A Gis-Assisted Soil Erosion Model At Watershed Level, Reynaldo L. Lanuza, Eduardo P. Paningbatan Jr

International Congress on Environmental Modelling and Software

Most erosion models have been developed based on a plot scale and have limited application to a watershed due to the differences in scale. In order to address this limitation, a GIS-assisted methodology for modeling soil erosion was developed using PCRaster to predict the rate of soil erosion at watershed level and identify the location of erosion prone areas. The GIS-assisted hydrology and erosion models were validated at Tanghaga Watershed using the observed values from previous experiment. The predicted peak rates, Qp, showed a highly significant relationship with the observed Qp, with an r2 value of 0.75. For soil loss …

Go to article

Modelling Flow And Concentration Field In Rectangular Water Tanks, F. Javier Martínez-Solano, Pedro L. Iglesias Rey, C. Gualtieri, P. Amparo López-Jiménez Jul 2010

Modelling Flow And Concentration Field In Rectangular Water Tanks, F. Javier Martínez-Solano, Pedro L. Iglesias Rey, C. Gualtieri, P. Amparo López-Jiménez

International Congress on Environmental Modelling and Software

Water storage tanks are usually designed with two objectives, i.e. to provide a specified maximum storage volume and to fix a certain total head over the water supply network. Only more recently, some attention has been paid to the water quality inside the storage tank since this can significantly affect the quality in the distribution systems. Sometimes conceptual models were proposed in the literature, but computational fluid dynamics (CFD) methods can be considered as the best analysis and predictive tool in storage tanks water quality studies. In this paper, FLUENT®, a commercial CFD code, was applied to model flow and …

Go to article

Integrated Modelling For The Conservation Of River Ecosystems: Progress In The South Australian River Murray, Brett A. Bryan, I. Overton, A. Higgins, K. Holland, R. E. Lester, D. King Jul 2010

Integrated Modelling For The Conservation Of River Ecosystems: Progress In The South Australian River Murray, Brett A. Bryan, I. Overton, A. Higgins, K. Holland, R. E. Lester, D. King

International Congress on Environmental Modelling and Software

Investment in water infrastructure and management can enhance the ecological health of water-dependent ecosystems along highly regulated rivers. Investment in new flow-control infrastructure and management of both existing and new infrastructure can help return natural environmental flows to achieve healthy and representative areas of river ecosystems. In this paper, we developed an integrated model to cost-effectively restore environmental flows and ecosystem health in the River Murray in South Australia. The model integrates a range of hydrological, ecological, economic, and social components. A hydrological model is used to identify spatial and temporal inundation dynamics given flow rates and weir operation. Ecological …

Go to article

Guidelines For Good Practice In Bayesian Network Modelling, Serena H. Chen, C. A. Pollino Jul 2010

Guidelines For Good Practice In Bayesian Network Modelling, Serena H. Chen, C. A. Pollino

International Congress on Environmental Modelling and Software

Bayesian networks (BNs) are used increasingly to model environmental systems, for reasons including their ability to: integrate multiple issues and system components; utilise information from different sources; and handle missing data and uncertainty. For a model to be of value in generating and sharing knowledge or providing decision support, it must be built using good modelling practice. This paper provides such guidelines to developing and evaluating Bayesian network models of environmental systems. The guidelines entail clearly defining the model objectives and scope, and using a conceptual model of the system to form the structure of the BN, which should be …

Go to article

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 …

Go to article

Multi-Scale Modelling Of Ecosystem Services – An Iterative Approach, M. S. Castellazzi, I. Brown, L. Poggio, Alessandro Gimona Jul 2010

Multi-Scale Modelling Of Ecosystem Services – An Iterative Approach, M. S. Castellazzi, I. Brown, L. Poggio, Alessandro Gimona

International Congress on Environmental Modelling and Software

Ecosystems are dependent upon the interactions between the natural environment and human factors. Each different ecosystem service is also associated with varying spatial scales related to their functioning and human benefits. Thus, key requirements for an ecosystem-based approach (EBA) are i) multiple scales, especially landscape scale, ii) flexible method for adaptive response and iii) stakeholders participation. Understanding complex inter-relationships between ecosystem functions and their services requires tools to handle change and uncertainty, notably scenarios and sensitivity analysis. We propose an iterative approach, which is multi-scale and userfocused based upon the LandSFACTS toolkit to generate a suite of land use change …

Go to article

Integrated Modelling For The Conservation Of River Ecosystems: Progress In The South Australian River Murray, Brett A. Bryan, I. Overton, A. Higgins, K. Holland, R. E. Lester, D. King Jul 2010

Integrated Modelling For The Conservation Of River Ecosystems: Progress In The South Australian River Murray, Brett A. Bryan, I. Overton, A. Higgins, K. Holland, R. E. Lester, D. King

International Congress on Environmental Modelling and Software

Investment in water infrastructure and management can enhance the ecological health of water-dependent ecosystems along highly regulated rivers. Investment in new flow-control infrastructure and management of both existing and new infrastructure can help return natural environmental flows to achieve healthy and representative areas of river ecosystems. In this paper, we developed an integrated model to cost-effectively restore environmental flows and ecosystem health in the River Murray in South Australia. The model integrates a range of hydrological, ecological, economic, and social components. A hydrological model is used to identify spatial and temporal inundation dynamics given flow rates and weir operation. Ecological …

Go to article

Remote Sensing Time Series For Modeling Invasive Species Distribution: A Case Study Of Tamarix Spp. In The Us And Mexico, Anna F. Cord, Doris Klein, Stefan Dech Jul 2010

Remote Sensing Time Series For Modeling Invasive Species Distribution: A Case Study Of Tamarix Spp. In The Us And Mexico, Anna F. Cord, Doris Klein, Stefan Dech

International Congress on Environmental Modelling and Software

Detecting invasive species and predicting their potential distribution are crucial to coordinate management responses. Remote sensing data are now available in several spatial and temporal resolutions and can supply environmental models with additional information. This study uses the Maximum Entropy algorithm to model the current distribution of the saltcedar (Tamarix spp.) in the US and Mexico and to identify suitable habitats, both already inhabited and not yet occupied. Tamarisk is restricted to specific habitats such as riparian zones, wetlands and agricultural or disturbed areas, which are typically not only characterized by climate. To describe vegetation phenology and thermal seasonality in …

Go to article

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 …

Go to article

Parameter Optimization And Bayesian Inference In An Estuarine Eutrophication Model Of Intermediate Complexity, P. Ding, C. E. S. Hoyle, M. E. Borsuk Jul 2010

Parameter Optimization And Bayesian Inference In An Estuarine Eutrophication Model Of Intermediate Complexity, P. Ding, C. E. S. Hoyle, M. E. Borsuk

International Congress on Environmental Modelling and Software

The Neuse River Estuary, North Carolina, has been experiencing severe consequences of eutrophication in recent years including excessive algal blooms, low levels of dissolved oxygen, declining shellfish populations, large fishkills, and outbreaks of toxic microorganisms. As in many other marine systems, nitrogen has been identified as the pollutant of concern in the estuary because it is believed to stimulate the excessive algal growth that is at the root of other ecological problems. A model incorporating the mechanisms of algal growth and nutrient consumption in the Neuse River Estuary is formulated mathematically and implemented in the computer software AQUASIM. Key model …

Go to article

Towards Adaptive Control Of Landscape Biodiversity, J. Gary Polhill, Andrew Jarvis, Alessandro Gimona, Nicholas M. Gotts Jul 2010

Towards Adaptive Control Of Landscape Biodiversity, J. Gary Polhill, Andrew Jarvis, Alessandro Gimona, Nicholas M. Gotts

International Congress on Environmental Modelling and Software

This paper reports work using a coupled agent-based model of land use changeand species metacommunity model (FEARLUS-SPOMM) to explore biodiversity incentivemechanisms using adaptive control algorithms. Existing work at the LancasterEnvironment Centre has shown that such algorithms can help in analysing the adaptivecapabilities of climate-related policy interventions under uncertainty. In particular,feedback control is a practical approach that mimics many recognisable features of adaptivedecision making processes, including the sequential review of models and policies in thelight of new observations. In a companion paper, we show that FEARLUS-SPOMM showsnonlinear dynamics in the relationship between agricultural incentives and biodiversityoutcome. In this pilot study, we …

Go to article

Carma: Scalability With Approximate-Model-Based Adaptation, John D. Hastings, Alexandre V. Latchininsky, Scott P. Schell Jul 2010

Carma: Scalability With Approximate-Model-Based Adaptation, John D. Hastings, Alexandre V. Latchininsky, Scott P. Schell

International Congress on Environmental Modelling and Software

Many complex physical systems such as biological systems are characterized both by incomplete models and limited empirical data. Accurate prediction of the behavior of such systems requires exploitation of multiple, individually incomplete, knowledge sources. Our approach, called approximate-model-based adaptation, utilizes case-based reasoning to provide an approximate solution and model-based reasoning to adapt this approximation into a more precise solution. This approach is implemented in CARMA, a decision-support system for grasshopper infestation advising which models experts and has been successfully used since 1996. Initially focused on rangeland grasshoppers within the state of Wyoming, CARMA’s capabilities have been extended to support the …

Go to article

First Prev Next Last