How political philosophies can help to discuss and differentiate theories in community ecology.

This paper uses structural analogies to competing political philosophies of human society as a heuristic tool to differentiate between ecological theories and to bring out new aspects of apparently well-known classics of ecological scholarship. These two different areas of knowledge have in common that their objects are 'societies', i.e. units composed of individuals, and that contradictory and competing theories about these supra-individual units exist. The benefit of discussing ecological theories in terms of their analogies to political philosophies, in this case liberalism, democratism and conservatism, consists in the fact that political philosophies show clear differences and particularities as regards their approach to the concepts of individuality and intentional action. The method therefore helps to expose peculiarities of ecological theories that are usually considered canonical (e.g. Clements, Gleason), as well as hybrid forms (E. P. Odum), and to differentiate between two different types of theories about functional wholes. The basis of this method is the constitutional-theoretical premise that modern paradigms of socialization structure the ecological discourse.

A quantitative review of urban ecosystem service assessments: concepts, models, and implementation.

Although a number of comprehensive reviews have examined global ecosystem services (ES), few have focused on studies that assess urban ecosystem services (UES). Given that more than half of the world's population lives in cities, understanding the dualism of the provision of and need for UES is of critical importance. Which UES are the focus of research, and what types of urban land use are examined? Are models or decision support systems used to assess the provision of UES? Are trade-offs considered? Do studies of UES engage stakeholders? To address these questions, we analyzed 217 papers derived from an ISI Web of Knowledge search using a set of standardized criteria. The results indicate that most UES studies have been undertaken in Europe, North America, and China, at city scale. Assessment methods involve bio-physical models, Geographical Information Systems, and valuation, but few study findings have been implemented as land use policy.

Structural diversity: a multi-dimensional approach to assess recreational services in urban parks.

Urban green spaces provide important recreational services for urban residents. In general, when park visitors enjoy "the green," they are in actuality appreciating a mix of biotic, abiotic, and man-made park infrastructure elements and qualities. We argue that these three dimensions of structural diversity have an influence on how people use and value urban parks. We present a straightforward approach for assessing urban parks that combines multi-dimensional landscape mapping and questionnaire surveys. We discuss the method as well the results from its application to differently sized parks in Berlin and Salzburg.