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"Cities and regions grow (or occasionally decline), and continuously transform themselves as they do so. This book describes the theory and practice of modeling the spatial dynamics of urban growth and transformation. As cities are complex, adaptive, self-organizing systems, the most appropriate modeling framework is one based on the theory of self-organizing systems -an approach already used in such fields as physics and ecology. The book presents a series of models, most of them developed using cellular automata (CA), which are inherently spatial and computationally efficient. It also provides discussions of the theoretical, methodological, and philosophical issues that arise from the models. A case study illustrates the use of these models in urban and regional planning. Finally, the book presents a new, dynamic theory of urban spatial structure that emerges from the models and their applications. The models are primarily land use models, but the more advanced ones also show the dynamics of population and economic activities, and are integrated with models in other domains such as economics, demography, and transportation. The result is a rich and realistic representation of the spatial dynamics of a variety of urban phenomena. The book is unique in its coverage of both the general issues associated with complex self-organizing systems and the specifics of designing and implementing models of such systems."--

Abstract
Chemical pollution of water bodies is a complex problem around the globe. When described by the extremes of the range of problem definitions, water bodies can be chemically polluted by a single compound that is emitted from a point source or an incidental spill, or by chronic diffuse emissions from local and upstream land uses. The resulting mixture exposures can vary in space and time, e.g. due to the use of pesticides in the crop growing season. The environmental management objectives are commonly to protect and restore surface waters against human influences. Currently, chemical pollution is globally judged for a selected set of compounds, by judging each of these individually in comparison with protective environmental quality standards. Research has provided a novel assessment paradigm (solution-focused risk assessment) and novel data, measurement methods and models to improve on current practices. Their adoption and application require establishing novel linkages between the diverse problem definitions and the novel approaches. That would assist water quality professionals to select the most effective option or options to protect and restore water quality. The present paper introduces the RiBaTox (River Basin Specific Toxicants assessment and management) web tool. It consists of short descriptions of the novel approaches (made available as Additional file 1) and a decision tree for end-users to select those. The overview of novel approaches collated in RiBaTox is relevant for end-users ranging from local water quality experts up till strategic policy developers. Although RiBaTox was developed in the context of European water quality problems, the methods provided by RiBaTox are relevant for users from (inter)national to local scales. This paper is part of a series of Policy Briefs from the EU-FP7 project SOLUTIONS (http://www.solutions-project.eu), which provide backgrounds on chemical pollution of surface waters and policy practices and proposed improvements.