Autor*innen mit den meisten Dokumenten
Auflistung nach:
Neueste Veröffentlichungen
- KonferenzbeitragUmweltinformationen im Internet – Ein „State of the Art”-Bericht(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Manderfeld, Carmen
- KonferenzbeitragHypermedia im Umweltschutz: Ein Thema kommt an im Fachausschuss Informatik im Umweltschutz(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Riekert, Wolf-Fritz; Tochtermann, Klaus
- KonferenzbeitragIntegrating the Process-based Simulation Model DNDC into GIS(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Huber, Stefan; Bareth, Georg; Doluschitz, ReinerSeveral trace gases, such as methane, nitrous oxide, nitric oxide, and ammonia, affect global climate change because of their radiative or chemical effects in the atmosphere. An important source of the four trace gases is soil. Agricultural land-use imposes a great deal of disturbance on soils by farming practices leading to elevated trace gas emissions. To assess emissions at regional scale we developed the software DNDC-GIS which integrates the mechanistic trace gas simulation model DNDC in a geographical information system (GIS). Additionally, to overcome the lengthy computation times, we implemented a load balancing module which allows deploying computational resources in a local-area network.
- KonferenzbeitragA Model for the Utilisation of Natural Resources for Silviculture(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Schönke, Ulrike; Köchel, PeterA model to determine economic harvesting policies under consideration of certain ecological constraints is presented. The forest is divided into stands and the optimisation task is to formulate a policy to determine, where and how much to fell. Demand is added in comparison with other researchers, which should be satisfied if possible. There are also different places of demand, e.g. lumber mills. Costs arising from harvesting and transportation can vary depending on the location of felling and the location of demand. As an underlying growth model, the presented method uses a matrix giving the transition probabilities of the forest after five years. The suggested approach is simulation optimisation using genetic algorithms. The results of this paper should assist policy managers in preliminary decision making.
- KonferenzbeitragHierarchical Asymmetric Cellular Automata for Multi-scale Modelling of Ecological and Socio-economic Systems(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Sonnenschein, Michael; Vogel, UteComplex ecological and socio-economic systems often have to be modelled spatially ex- plicitly. Therefore, cellular automata (CA) are a widely used method for such applica- tions. But CA in its original form do not allow to model processes on different time scales and also define a common grid for all processes. This problem can be overcome by an extension of CA called HACA, introduced in this short paper. HACA allow multi- ple-scale modelling of spatially explicit processes based on a formally defined extension of CA. HACA can be used for practical applications by extending a C++-framework that allows a maximum of freedom to define local dynamics of cell's behaviour.
- KonferenzbeitragStock and Fishery Dynamics of Coregonus Lavaretus of Lake Sevan, Armenia(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Gabrielyan, BardukhReduction in water level of Lake Sevan brought about by hydroconstruction and abstraction of water for irrigation has essentially changed the lake’s ecological regime. Changes of the lake's ecosystem have resulted in considerable disturbance of habitats of fish affecting mostly their natural reproduction and food provision conditions (Rubenian 1997, 6). Recent years due to secondary eutrophication of the lake and intensified illegal fishing, populations of all commercial type fish have been depressed (Gabrielyan 1998, 3). In the present paper, the trends of the dynamics of Coregonus lavaretus stock from 1979-1998 are revealed and an attempt is made to give short-term forecast of catch of this species in Lake Sevan. For choosing the most appropriate stock estimation method retrospective analyses are done for two types of fishing gears purse seine net and gillnet. Analysis of the obtained data has shown that in 1990s a tendency in the population toward rejuvenation is observed in parallel with depletion of its stock. It should be noted that in the preceding period the main regulating factor having impact on the stock was change of water quality caused by the changes of the reservoir's regime, while for recent years the main factor is the fishing pressure caused by uncontrolled overfishing. Drastic reduction of stock of C. lavaretus as a result of fishery may result in misbalance of its food base, accumulation of excessive organic matter in the lake and therefore, aggravation of eutrophication processes there.
- KonferenzbeitragAn Information System for the Management of Ecological Simulations(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Köster, Frank; Finke, Jens; Frank, Karin; Sonnenschein, MichaelOur paper deals with the information system Info-X. This software system aims at the management of ecological studies and provides a special functionality for simulation studies. In particular, Info-X can be seen as an approach to conserve the wealth of knowledge and experience, which manifests in models, simulation programs, and their practical applications. This knowledge/experience can broadly support research in theoretical and practical ecology. Info-X provides a state-of-the-art graphical user-interface to browse its database, select desired content, start simulation runs with suitable simulators, and check published results for plausibility/correctness. Furthermore, users can assess and rate the quality of existing content and are invited to submit new content.
- KonferenzbeitragPossible Applications and Constraints of the ECOSIM Project in the Polish Test Site(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Tomczak, ZbigniewThe ECOSIM project treats about a model-based information and a decision support system for urban environmental management. It integrates data acquisition and monitoring systems, GIS, and dynamic simulation models in flexible client-server architecture based on standard protocols. The first phase of the ECOSIM project consists in a detailed project plan, a quality and a dissemination plan, a range of technical specifications, and an initial ECOSIM Demonstrator. The second project phase concentrates on the implementation of the Demonstrator at the three validation sites Athens, Berlin, Gdansk.
- KonferenzbeitragThe German Housing Stock 2025 – Modelling the Effects of Sustainability - Scenario with BASiS II(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Deilmann, ClemensOngoing analyses of energy and mass flow of the housing sector in Germany have the agenda, to estimate environmental impact of the housing sector including the necessary technical infrastructure of residential areas along different development scenarios. A software-tool -BASiS IIdescribes the existing housing stock of Germany and allows the modelling of development paths. The model allows to estimate the resource consumption for residential purpose along different fractions, the relevant emissions and the future land use. A further application of the model is to spot the essential influencing factors of alternative paths and options to act.
- KonferenzbeitragModelling and Simulation of Internal Pollution of Shallow Lakes(Environmental Communication in the Information Society - Proceedings of the 16th Conference, 2002) Gnauck, Albrecht; Luther, Bernhard; Heinrich, RalphIn this paper results of a water quality modelling framework for riverine shallow lakes are presented. Based on investigations of interrelations between variables of freshwater quality by advanced time series analysis methods a process model for phosphorus remobilisation from lake sediments was developed. For predicting the changing water quality of shallow riverine lakes caused by internal pollution this submodel was included into the eutrophication model HavelMod. Simulations of water quality variables for different river-lake sections as phytoplankton biomass, phosphate phosphorus, ammonia nitrogen and nitrate nitrogen, which are important for water quality management activities, are discussed.