David Lam

Integration of a Nonpoint Source Pollution Model with a Decision Support System

Abstract This paper is a progress report of an ongoing research project from which the expected final product will be an integral system to model nonpoint source pollution in surface waters. Diffuse pollution models will be included in a decision support system with a unique platform, common interfaces and GIS capabilities. This system will accommodate pre- and post-processing tools, model control and sensitivity analysis for the parameters in the models. Particularly, the construction of the interface for the AGNPS model and its link with the decision support system RAISON is presented. The model is described, including the input requirements, the development of tools and the procedures created to extract the necessary data from digital elevation model, soil type and landcover vectorized files.

Development of an environmental flows decision support system

Abstract The Murray–Darling Basin in Australia is severely environmentally degraded as a result of a range of anthropogenic changes, most notably the regulation and extraction of surface water resources for irrigated agriculture. Environmental problems include eutrophication of rivers and storages, elevated salinity levels, widespread blooms of toxic blue–green algae, decline of native fish and bird populations, and reduction of area of riverine wetlands. Both the community and the government are committed to improving the state of the environment in the Basin, both for its intrinsic ecological values, and to ensure the sustainability of production in what is Australias most economically important agricultural region. To facilitate the on-going trade-off process between competing users of this resource, a decision support system (DSS) is being developed which will enable explicit prediction of the likely response of key features of the riverine environment to proposed flow management scenarios. The DSS is being developed using the RAISON shell ( Lam, D.C.L., Mayfield, C.I., Swayne, D.A., Hopkins, K., 1994. A prototype information system for watershed management and planning. Journal of Biological Systems 2 (4), 499–517 ), and will integrate a range of simple models of riverine ecology which are being developed. These models will include qualitative and quantitative models representing the response of different aspects of the instream and floodplain ecology dependent upon the river flow regime. The DSS will not include a detailed model of river hydrology or hydraulics, but rather, will use the output from the range of such models currently in use in the Basin as inputs to the ecological models. The DSS will also provide a range of tools to allow user-defined evaluation of scenario results, as well as explanations and supporting information to elucidate the ecological modelling.

Modelling Changes in Stream Water Quality Due to Climate Change in a Southern Ontario Watershed

This research represents a pilot project to establish a methodology for assessing the sensitivity of watershed stream water quality to changes in water quantity caused by climate change. The pilot watershed is the Duffins Creek watershed, located 20 km east of the City of Toronto, Canada. Scenarios of climate change analyzed in this project were drawn from two internationally recognized climate models: the Canadian Centre for Climate Modelling and Analysis (CCCma) CGCM1 and the Hadley Centre HadCM2. The AGNPS (Agricultural Non-Point Source) model was used to predict changes in stream water chemistry. The results are compared to baseline conditions as well as future conditions based on 2020 land use scenarios. It was determined that 2020 land use scenarios typically result in much smaller changes in peak flows than are predicted for the climate change scenarios, especially the wet climate change scenarios. Understanding climate change responses is critical for the development of watershed plans and drinking water source protection studies. Currently, watershed studies are completed using climate information based on relatively short-term monitoring databases that reflect past weather patterns. It is widely understood that management actions advocated in watershed studies could be improved if consideration were given to the implication of climate changes.

Integrated Assessments Of River Health Using Decision Support Software

A prototype decision support system has been developed to assess the environmental outcomes of proposed flow regimes for the regulated, lowland floodplain rivers of the Murray-Darling Basin in Australia. The DSS assesses the environmental outcomes of proposed flow regimes primarily by providing integrated assessments of river health at different spatial scales based on the outputs from riverine habitat condition and riverine nuisance species models. These models rely on data from river hydrology simulation models — both within and external to the DSS. The current version of the software includes three models of riverine habitat condition: native fish, floodplain vegetation, and waterbird breeding. The only riverine nuisance species model currently included is a model to predict the severity of blue-green algal blooms. In this paper a brief description of the DSS framework and the nature of the underlying models is provided. The paper focuses on describing the methods used to integrate the individual model outputs into overall river health assessments.

DATA AND KNOWLEDGE VISUALIZATION IN AN ENVIRONMENTAL INFORMATION SYSTEM

An environmental information system is an important tool in conducting ecosystem research that integrates data and knowledge from many disciplinary studies. Effective computer visualization of these data and knowledge leads to better communication and understanding of the individual results and the concept of the ecosystem approach. By using examples from an environmental information system prototype, the advantages and issues surrounding the development and application of visualization methodologies will be discussed. It was found that while data visualization techniques have advanced significantly, the knowledge representation and visualization procedures have not been fully developed. Further work in this area was recommended particularly in view of the demand for better knowledge exchange mechanisms among scientists with different disciplines.

A Teamwork Approach to Decision Support System Development for Watershed Management Problems

Decision-support systems (DSS) for solving complex environmental problems are not merely computer software systems. A working system requires data and knowledge inputs from domain scientists and the results need to be easily understandable to decision makers. It must be designed with both scientists and end users in mind, and must involve them early in the development, all working as a team. They need to overcome attitude and communication problems that exist among them and the system. This paper discusses the issues surrounding a team approach of building a DSS.