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Fuzzy Prediction Of The Algal Blooms In The Orbetello Lagoon, Stefano Marsili-Libelli, G. Pacini, C. Barresi Jul 2002

Fuzzy Prediction Of The Algal Blooms In The Orbetello Lagoon, Stefano Marsili-Libelli, G. Pacini, C. Barresi

International Congress on Environmental Modelling and Software

The Orbetello lagoon is a shallow brackish waterbody subject to intense and diverse eutrophication (phytoplancton, macroalgae and macrophytes). Periodically a large amount of algae must be artificially removed, their collection and disposal representing a considerable management cost. This paper describes the design of a bloom predictor based on the daily fluctuations of simple water quality parameters such ad dissolved oxygen, oxidation-reduction potential, pH and temperature. The task of the fuzzy predictor is to recognise the possibility that a bloom of the macroalgae population is about to occur based on the changing daily pattern of these variables. The fuzzy predictor is …

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Population Dynamics And Treatment Strategies Of Phytophthora Infestans (Late Blight) In The Mid-Hills Of Nepal, Heico Apel, M. S. Paudyal, O. Richter Jul 2002

Population Dynamics And Treatment Strategies Of Phytophthora Infestans (Late Blight) In The Mid-Hills Of Nepal, Heico Apel, M. S. Paudyal, O. Richter

International Congress on Environmental Modelling and Software

The fungus Phytophthora infestans is a major ubiquitous pest in solanaceous crops and causes great damages in the agricultural systems in Nepal. This is especially true in the cash crop orientated areas of the Mid-Hills and the Terai region, where potato and tomato cropping is a prominent income source of the rural population. This fact in combination with cheap and readily available pesticides is responsible for the frequent and perceived over-use of chemical plant protection agents. Based on this background a series of agronomic field trials in the Jhikhu-Khola watershed aiming at the optimisation of P. infestans treatment strategy was …

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Modular Ecosystem Modeling, Alexey Voinov, Carl Fitz, Thomas Maxwell, Roelof Boumans, Robert Costanza Jul 2002

Modular Ecosystem Modeling, Alexey Voinov, Carl Fitz, Thomas Maxwell, Roelof Boumans, Robert Costanza

International Congress on Environmental Modelling and Software

The modular ecosystem modeling approach was used to create a flexible landscape model structure that is easy to modify and extend for particular case studies and applications. The Library of Hydro Ecological Modules (LHEM; http://iee.umces.edu/LHEM) includes modules that describe hydrologic processes, nutrient cycling, vegetation growth, decomposition, etc., both locally and spatially. LHEM is implemented within the framework of the Spatial Modeling Environment (SME; http://iee.umces.edu/SME3) that integrates modules and places local simulation models into a spatial context. The LHEM was used to build the Patuxent Landscape Model (PLM) as well as models of several subwatersheds of the Patuxent. Local ecosystem dynamics …

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Integrative Environmental Prediction Using Bayesian Networks: A Synthesis Of Models Describing Estuarine Eutrophication, M. E. Borsuk, C.A. Stow, K. H. Reckhow Jul 2002

Integrative Environmental Prediction Using Bayesian Networks: A Synthesis Of Models Describing Estuarine Eutrophication, M. E. Borsuk, C.A. Stow, K. H. Reckhow

International Congress on Environmental Modelling and Software

The symptoms of coastal and estuarine eutrophication are the result of a number of interacting processes operating at multiple spatial and temporal scales. Thus, models developed to appropriately represent each of these processes are not easily combined into a single predictive model. We suggest that Bayesian networks provide a possible solution to this problem. The graphical structure explicitly represents cause-and-effect assumptions between system variables that may be obscured under other approaches. These assumptions allow the complex causal chain linking management actions to ecological consequences to be factored into an articulated sequence of conditional relationships. Each of these relationships can then …

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Implementation Of A Multiagent Prototype For Wwtp Management, F. Borrell, D. Riaño, Miquel Sànchez-Marrè, Ignasi Rodríguez-Roda Jul 2002

Implementation Of A Multiagent Prototype For Wwtp Management, F. Borrell, D. Riaño, Miquel Sànchez-Marrè, Ignasi Rodríguez-Roda

International Congress on Environmental Modelling and Software

The control and management of a Wastewater Treatment Plant (WWTP) is a complex task that requires the supervision of human experts. To ease this task, Multiagent Systems provide a framework for a more efficiently control in environmental processes. A prototype of multiagent system has been designed for WWTP management. Two subgroups of agents are identified: the interface and the intelligent agents. The first subgroup is designed to interact with the plant and the final users. This group contains the monitoring agent, which is used to store and manage all the sensor data incomes, the actuator agent which acts on the …

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Probabilistic Finite Automata And Randomness In Nature: A New Approach In The Modelling And Prediction Of Climatic Parameters, L. Mora-López, R. Morales-Bueno, M. Sidrach-De-Cardona, F. Triguero Jul 2002

Probabilistic Finite Automata And Randomness In Nature: A New Approach In The Modelling And Prediction Of Climatic Parameters, L. Mora-López, R. Morales-Bueno, M. Sidrach-De-Cardona, F. Triguero

International Congress on Environmental Modelling and Software

A model to characterize and predict continuous time series from machine learning techniques isproposed. This model includes the following three steps: dynamic discretization of continuous values,construction of probabilistic finite automata and prediction of new series with randomness. The first problemin most models from machine learning is that they are developed for discrete values; however, mostphenomena in nature are continuous. To convert these continuous values into discrete values a dynamicdiscretization method has been used. With the obtained discrete series, we have built probabilistic finiteautomata which include all the representative information which the series contain. The use of probabilisticfinite automata allows us …

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Parsimonious Catchment And River Flow Modelling, R. H. Khatibi, R. J. Moore, Martijn J. Booij, D. Cadman, G. Boyce Jul 2002

Parsimonious Catchment And River Flow Modelling, R. H. Khatibi, R. J. Moore, Martijn J. Booij, D. Cadman, G. Boyce

International Congress on Environmental Modelling and Software

It is increasingly the case that models are being developed as “evolving” products rather than one-off application tools, such that auditable modelling versus ad hoc treatment of models becomes a pivotal issue. Auditable modelling is particularly vital to “parsimonious modelling” aimed at meeting specific modelling requirements. This paper outlines various contributory factors and aims to seed proactively a research topic by inextricably linking value/risk management to parsimonious modelling. Value management in modelling may be implemented in terms of incorporating “enough detail” into a model so that the synergy among the constituent units of the model captures that of the real …

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Weathering In Terrestrial Ecosystems: Carbon Sink, P. Egorov, Yuri Svirezhev Jul 2002

Weathering In Terrestrial Ecosystems: Carbon Sink, P. Egorov, Yuri Svirezhev

International Congress on Environmental Modelling and Software

In the framework of "active planetary cover" concept the influence of weathering on the atmosphere carbon and, as a consequence, on the climate is considered. The relatively slow process of chemical weathering, which is accompanied by an uptake of carbon from the atmosphere and its transportation to the intercontinental and epicontinental seas, is significantly amplified by terrestrial ecosystems. The mechanism of amplification is explained by an increase in CO2 concentration in the "soil" atmosphere caused by root respiration and the metabolism of micro-organisms, the so-called "respiration of soil". In accordance with Zavarzin’s estimation, the concentration of CO2 in the soil …

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Solving The Inverse Problem In Stochastic Groundwater Modelling With Artificial Neural Networks, C. Rajanayaka, S. Samarasinghe, D. Kulasiri Jul 2002

Solving The Inverse Problem In Stochastic Groundwater Modelling With Artificial Neural Networks, C. Rajanayaka, S. Samarasinghe, D. Kulasiri

International Congress on Environmental Modelling and Software

In this paper, prediction capability of a hybrid Artificial Neural Networks (ANN) was investigatedto solve the groundwater inverse problem. Initially, a Multi Layer Perceptron (MLP) network was developedand it was found that network produced better results when the target range of the parameters is smaller.Therefore, a Self-Organising Network (SON) was used to identify the objective subrange of the parameterand then the MLP model was employed to obtain final estimates. The data for the ANN was obtained from anumerical model that was utilised to simulate the solute transport in saturated groundwater flow. The forwardproblem of the numerical model was solved to …

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Data-Based Mechanistic And Top-Down Modelling, Peter C. Young Jul 2002

Data-Based Mechanistic And Top-Down Modelling, Peter C. Young

International Congress on Environmental Modelling and Software

The paper discusses the problems associated with environmental modelling and the need to develop simple, ‘top-down’, stochastic models that match the information content of the data. It introduces the concept of Data-Based Mechanistic (DBM) modelling and contrasts its inductive approach with the hypotheticodeductive approaches that dominate most environmental modelling research at the present time. The major methodological procedures utilized in DBM modelling are outlined and two practical examples illustrate how it has been applied in a hydrological and water quality context. The use of this same methodology as a basis for the evaluation and simplification of large deterministic simulation models …

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Optimization Of A Model To Predict Salinity Intrusion In San Francisco Bay Estuary Using A Genetic Algorithm, T. Rajkumar, David E. Thompson Jul 2002

Optimization Of A Model To Predict Salinity Intrusion In San Francisco Bay Estuary Using A Genetic Algorithm, T. Rajkumar, David E. Thompson

International Congress on Environmental Modelling and Software

Salinity intrusion is a significant issue in the San Francisco Bay Delta because this estuarycontributes substantially to fresh water supply for much of northern California. Traditionally, salinity alongthe estuary has been measured using monitoring instruments installed at various locations within theSacramento-San Joaquin River Delta system, and these measurements are used to predict future conditionsand evaluate the water management alternatives. The California Department of Water Resources DeltaSimulation Model (DWRDSM) is used for this type of analysis. DWRDSM is an unsteady one-dimensionalhydrodynamic and salt transport model. It can provide estimates of salinity at almost any location within theBay-Delta system. However, like many …

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A Grid-Generation Based Method For Information Fusion, Tian Xiang Yue, Ji Yuan Liu, Ying An Wang Jul 2002

A Grid-Generation Based Method For Information Fusion, Tian Xiang Yue, Ji Yuan Liu, Ying An Wang

International Congress on Environmental Modelling and Software

Relative studies on multi-scale information fusion, multi-source information fusion and multi-sensor information fusion are reviewed. On the basis of analyzing problems in existing methods of information fusion, a grid-generation model for simulating population density of China is proposed as a case of multi-source information fusion. By fusing remotely sensed data, meteorological data, soil data and statistical data, spatial distribution of population density in China is successfully simulated, in which grid generation process is described in detail. In addition, the basic idea of a grid-generation model as a case of multi-scale information fusion is discussed. The models for multi-source information fusion …

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Long Run Technical Change In An Energy-Environmenteconomy (E3) Model For An Ia System, J. H. Köhler Jul 2002

Long Run Technical Change In An Energy-Environmenteconomy (E3) Model For An Ia System, J. H. Köhler

International Congress on Environmental Modelling and Software

A world macroeconomic model is being developed to investigate policies for climate change and sustainabledevelopment, as a module of an IAM structure for the UK Tyndall Centre. This requires an economic modelfor the next 50-100 years, to show how changes in industrial structure and technology change GHGemissions. There is no suitable and generally accepted theory of long term technical change/development(Kondratiev waves) for incorporation in a macroeconomic modelling structure. However, there is now a gooddescriptive theory, which is intended to provide an economic history perspective of long term change. This isFreeman and Louçν (2001). The objective of our model is to …

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The Iclips Impacts Tool: Presenting Climate Impact Response Functions For Integrated Assessments Of Climate Change, Hans-Martin Fussel Jul 2002

The Iclips Impacts Tool: Presenting Climate Impact Response Functions For Integrated Assessments Of Climate Change, Hans-Martin Fussel

International Congress on Environmental Modelling and Software

The ICLIPS model is an integrated assessment model of climate change that links global climate change with regional impacts and mitigation efforts by integrating components from different disciplines and various spatial scales. Its reduced–form impact module consists of climate impact response functions (CIRFs) that depict the regional sensitivity of selected climate–sensitive impact sectors to changes in important climatic and atmospheric drivers. In addition to enabling the specification of maximum “tolerable” impacts of climate change in a tolerable windows analysis with the ICLIPS model, the CIRFs are also a valuable information source in their own right. In this paper, I present …

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Efficient Compensation Payments For The Protection Of Species: Application Of An Ecological-Economic Model, Martin Drechsler, Karin Johst, Frank Wätzold Jul 2002

Efficient Compensation Payments For The Protection Of Species: Application Of An Ecological-Economic Model, Martin Drechsler, Karin Johst, Frank Wätzold

International Congress on Environmental Modelling and Software

We present an ecological-economic modelling procedure to design compensation payments for species protection. In order to find an ecologically effective and economically efficient design, we choose an interdisciplinary approach that combines both ecological and economic knowledge. We develop our procedure on the example of White Stork protection in a spatio-temporally structured landscape generated by human land use. The ecological knowledge is synthesised in a simulation model, which includes the energy balance of individual storks, and their foraging behaviour to determine the effectiveness of land use practices measured by the number of surviving nestlings. Cost data of different land-use patterns are …

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A Decision Support Gis For The Clean Water Act Permit Review Analysis, Wei (Wayne) Ji, Rima A. Wahab, Jia (Jane) Ma Jul 2002

A Decision Support Gis For The Clean Water Act Permit Review Analysis, Wei (Wayne) Ji, Rima A. Wahab, Jia (Jane) Ma

International Congress on Environmental Modelling and Software

Section 404 of the Clean Water Act is the primary federal statute of the United States that regulates the discharge of dredged or fill materials into lakes, rivers, and wetlands. The Section 404 permit review process involves comprehensive assessments of physical, biological, ecological, and socioeconomic impacts of potential human alterations on aquatic ecosystems across spatial scales. Such assessments require the integration of management decision-making with innovative data handling techniques and assessment methodology. The Section 404-permit process is often hindered by the lack of well-developed scientific information and the technical tools for efficient data analysis. The individual permit review frequently becomes …

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Catchment Modelling – A Resource Manager’S Perspective, J.E. Caminiti Jul 2002

Catchment Modelling – A Resource Manager’S Perspective, J.E. Caminiti

International Congress on Environmental Modelling and Software

Models are invaluable tools for resource management. Models help resource managers develop a shared conceptual understanding of complex natural systems, allow testing of management scenarios, predict outcomes of high risk and high cost environmental manipulations, and set priorities. Catchment modelling is a specialist field, and different modelling approaches are specialist areas in themselves. There are a plethora of models available that apply to integrated catchment management, from micro to landscape scales, from deterministic models to broad-brush models. Different philosophies abound; with some experts advocating top-down systems approaches and others who dismiss these as being too uncertain and based on opinion …

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A Comparison Of Model Structures For The Simulation Of Amphipod (Talitrus Saltator) Population Dynamics., P. M. Anastácio, S. C. Gonçalves, M. A. Pardal, J. C. Marques Jul 2002

A Comparison Of Model Structures For The Simulation Of Amphipod (Talitrus Saltator) Population Dynamics., P. M. Anastácio, S. C. Gonçalves, M. A. Pardal, J. C. Marques

International Congress on Environmental Modelling and Software

A dynamic model is proposed in order to simulate sandhopper (Talitrus saltator) populationdynamics under various scenarios. It was built under the Stella simulation software and so far it has attainedthe calibration and verification stages. The basic structure of the model depends on the simulation of thenumber of animals in each age class (45 days). A von Bertalanffy growth curve has been adjusted to thetreated field data. From this equation another one expressing the instantaneous growth rate was extracted andused to calculate the growth. The number of individuals in each age class increases due to the ageing processi.e. new individuals coming …

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Designing A Multi-Agent System For Integrated Protection In Agriculture, A. Perini, A. Susi Jul 2002

Designing A Multi-Agent System For Integrated Protection In Agriculture, A. Perini, A. Susi

International Congress on Environmental Modelling and Software

Integrated Protection (IP) in agriculture consists of a set of practices aimed at favoring the set upof a development model characterized by a reduced environmental impact. The application of IP practicesin plant disease management by growers and agronomists requires both specialistic skills, historical data andinformation on chemicals and on low impact techniques for pest management. These sources of informationand knowledge are distributed among different actors in the agriculture production system.Recent approaches in developing decision support systems for agriculture, and more generally for environmentalproblems management, tend to adopt a “systemic” approach. That is to say a problem is considered for itsdependencies …

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Intelligent Model Management In A Forest Ecosystem Management Decision Support System, Donald Nute, Walter D. Potter, Frederick Maier, Jin Wang, Mark Twery, H. M. Rauscher, Peter Knopp, Scott Thomasma, Mayukh Dass, Hajime Uchiyama Jul 2002

Intelligent Model Management In A Forest Ecosystem Management Decision Support System, Donald Nute, Walter D. Potter, Frederick Maier, Jin Wang, Mark Twery, H. M. Rauscher, Peter Knopp, Scott Thomasma, Mayukh Dass, Hajime Uchiyama

International Congress on Environmental Modelling and Software

Decision making for forest ecosystem management can include the use of a wide variety of modeling tools. These tools include vegetation growth models, wildlife models, silvicultural models, GIS, and visualization tools. NED-2 is a robust, intelligent, goal-driven decision support system that integrates tools in each of these categories. NED-2 uses a blackboard architecture and a set of semi-autonomous agents to manage these tools for the user. The blackboard integrates a Microsoft Access database and Prolog clauses, and the agents are implemented in Prolog. A graphical user interface written in Visual C++ provides powerful inventory analysis tools; dialogs for selecting timber, …

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Feeding Elk In Greater Yellowstone: A Case Study In Ex-Ante Group Decision Support, Lynne Caughlan, D.L. Hoag Jul 2002

Feeding Elk In Greater Yellowstone: A Case Study In Ex-Ante Group Decision Support, Lynne Caughlan, D.L. Hoag

International Congress on Environmental Modelling and Software

Natural resource management decisions are complicated by multiple property rights, management objectives, and stakeholders with varying degrees of influence over the decision making process. Managers must consider all opinions when they develop management policies. Often this type of information is not understood until after a decision has been made, which can result in wasted time and effort. We developed an institutional framework to predict stakeholders’ influence in the resource management decision-making process before the stakeholder meetings actually occur. Then we applied the framework to an actual case study concerning whether to feed elk over the winter in the Greater Yellowstone …

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Classifying Environmental System Situations By Means Of Case-Based Reasoning: A Comparative Study, Héctor Núñez, Miquel Sànchez-Marrè, Ulises Cortés, Quim Comas, Montse Martínez, Manel Poch Jul 2002

Classifying Environmental System Situations By Means Of Case-Based Reasoning: A Comparative Study, Héctor Núñez, Miquel Sànchez-Marrè, Ulises Cortés, Quim Comas, Montse Martínez, Manel Poch

International Congress on Environmental Modelling and Software

The step of identifying to which class of operational situation belongs the current Environmental System situation is a key element to build successful Environmental Decision Support Systems (EDSS). Case-Based Reasoning (CBR) is a good technique to solve new problems based in previous experience. Main assumption in CBR relies in the hypothesis that similar problems should have similar solutions. When working with labelled cases, the retrieval step in CBR cycle can be seen as a classification task. The new cases will be labelled (classified) with the label (class) of the most similar case retrieved from the Case Base. In Environmental Systems, …

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The Streames Project: Linking Heuristic And Empirical Knowledge Into An Expert System To Assess Stream Managers, Joaquim Comas, Esther Llorens, Manel Poch, G. Markakis, T. Battin, S. Gafny, E. Maneux, E. Martí, M. Morais, M. A. Puig, M. Pusch, J. L. Riera, F. Sabater, A. G. Solimini, P. Vervier Jul 2002

The Streames Project: Linking Heuristic And Empirical Knowledge Into An Expert System To Assess Stream Managers, Joaquim Comas, Esther Llorens, Manel Poch, G. Markakis, T. Battin, S. Gafny, E. Maneux, E. Martí, M. Morais, M. A. Puig, M. Pusch, J. L. Riera, F. Sabater, A. G. Solimini, P. Vervier

International Congress on Environmental Modelling and Software

The increase in stream nutrient loads from anthropogenic sources has become a serious problem, especially in developed regions. Humans affect streams by modifying the landscape in ways that increase the transport of nutrients to surface waters, by directly dumping urban or industrial sewage into the stream, or by modifying streams in ways that reduce their ability to respond to increased nutrient loads. In Mediterranean regions these problems are compounded by the scarcity of water. The decision-making processes involved in water quality management require extensive human expertise or extensive computation with large data sets. In this sense, the STREAMES project aims …

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Environmental Foresight And Structural Change, M. B. Beck Jul 2002

Environmental Foresight And Structural Change, M. B. Beck

International Congress on Environmental Modelling and Software

Policy-makers and the public, it has famously been said [Brooks, 1986], are more interested in the possibility of non-linear dislocations and surprises in the behavior of the environment than in smooth extrapolations of current trends. How indeed should we design our models to generate environmental foresight, to detect, in particular, threats to our environment lying “just beyond the horizon”? In facing this prospect of potentially profound dislocations in behavior, the problem is that the number of state variables in the model, whether they interact, how they interact, and the form of their interactions, may be evolving over time. What may …

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Contaminated Industrial Sites, Real-Time Monitoring, Knowledge-Based Systems, Modelling, Knowledge Acquisition, Alexander Komarov, Oleg Chertov, G. Andrienko, N. Andrienko, Alexey Mikhailov, P. Gatalsky Jul 2002

Contaminated Industrial Sites, Real-Time Monitoring, Knowledge-Based Systems, Modelling, Knowledge Acquisition, Alexander Komarov, Oleg Chertov, G. Andrienko, N. Andrienko, Alexey Mikhailov, P. Gatalsky

International Congress on Environmental Modelling and Software

Decision support in sustainable forest management (SFM) has some specific features: a) it can perform quantitative prediction of forest ecosystem dynamics under different scenarios of SFM; b) it can spatially combine the predictions of different scenarios on the territory of a forest unit to support decisionmaking. We represent the integration of simulation modelling with the exploratory spatial data analysis (ESDA). The EFIMOD 2 is a spatially explicit individual-based ecosystem model, which was run for simulation of forest ecosystem dynamics at stand level on the territory of a state forest in Central European Russia. The DESCARTES software system designed to support …

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Ecosystem As A Text: Semantic Analysis Of The Global Vegetation Pattern, Yuri Svirezhev Jul 2002

Ecosystem As A Text: Semantic Analysis Of The Global Vegetation Pattern, Yuri Svirezhev

International Congress on Environmental Modelling and Software

Let us consider a text, which is written by Russian language. At the first level of reception we know only a number of letters. Then the information per one letter I1=5bits. At the second level of perception we take into account the frequencies of letters then I2=4.35bits. At the next levels, when we take into account double, triple, etc. correlations, we get I3=3.5bits, I4=3bits, etc. Then the redundancy of information at each level, Ri=1-Ii/I1, is equal to R1=0, R2=0.13, R3=0.3, R4=0.4, etc. By defining the cost of information as a degree of non-redundancy, Ci=1/(1-Ri) we get C1=1 C2=1.15, C3=1.43, C4=1.67, …

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A Conceptual Model For Integrated Assessment, Markus Knoflacher Jul 2002

A Conceptual Model For Integrated Assessment, Markus Knoflacher

International Congress on Environmental Modelling and Software

The challenge of integrated assessment is the integration of scientific and social aspects for the preparation of decisions. On one hand it is necessary to find scientific and technologically sound solutions, on the other hand the results should meet the interests of social groups affected by the particular project. In large projects it is also necessary to consider the effects on sustainable development. The bandwidth of the different aspects is in practise confronted with problems in acquisition of data, inhomogeneity and incompleteness of information about the actual conditions and the effects of the project. To solve the task in a …

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Trees, Dendrograms And Sensitivity, R. D. Braddock Jul 2002

Trees, Dendrograms And Sensitivity, R. D. Braddock

International Congress on Environmental Modelling and Software

Dendrograms and minimum-weight spanning trees (MWST) are discrete structures which arise inclustering theory, networks, and where strategic choices are made between discrete options. The discrete structureof the solution tree varies discontinuously with respect to changes in the dissimilarity or cost matrix. Tarjan[1982] has obtained bounds on the changes to the elements of the cost matrix, where the structure is not altered.These results are extended to describe the sensitivity of the tree structure with respect to changes in the costmatrix. The sensitivity of the structure to the addition of a node and arcs is solved using potential loops in thetree. This …

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Integrated Systems Analysis And Sustainable Development, Tad Soroczynski Jul 2002

Integrated Systems Analysis And Sustainable Development, Tad Soroczynski

International Congress on Environmental Modelling and Software

The paper presents integrated systems analysis (ISA) as a "tool" for modelling and for thedevelopment of decision support systems (DSS). ISA enhances understanding of the complex relationshipsbetween different disciplines in the form of inputs fi transformations fi outputs and also facilitates anunderstanding of the term sustainable development. Further, the paper presents a definition and model of ISAand discusses performance of component systems or distribution patterns in relation to a time horizon. Somecomponent systems create constraints and impact other component systems which over time undergotransformations such as self-organisation and self-regulation. Some component systems may adopt a distributionpattern as an output. Therefore, …

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Indirect Effect Of Habitat Destruction On Ecosystems, Nariyuki Nakagiri, K. Tainaka Jul 2002

Indirect Effect Of Habitat Destruction On Ecosystems, Nariyuki Nakagiri, K. Tainaka

International Congress on Environmental Modelling and Software

Habitat destruction is one of the primary causes of species extinction in recent history. Even if the destruction is restricted to a local and small area, its accumulation increases the risk of extinction. To study local destruction of habitat, we present a lattice ecosystem composed of prey (X) and predator (Y). This system corresponds to a lattice version of the Lotka-Volterra model, where interaction is allowed between neighboring lattice points. The lattice is partly destroyed, and destructed sites or barriers are randomly located between adjacent lattice points with the probability p. The barrier interrupts the reproduction of X, but the …

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