The development of urban ecosystems is usually restricted by a few key limiting factors, including both the natural resource condition and the socioeconomic performance. To link the natural, economic and social subsystems together and uniformly measure the multiple ecological flows within and amongst these subsystems, emergy analysis was applied in this paper to describe the status quo of urban...

Green infrastructure consists of ecosystems that provide valuable services to urban areas. Constructed ecosystems, including green roofs, bioretention systems, constructed wetlands and bioreactors are artificial, custom-built components of green infrastructure that are becoming more common in cities. Small size, strong spatial boundaries, ecological novelty and the role of human design characte...

generalized interactions flexible acquaintances/interactions reactive capabilities pro-active capabilities

The field of urban ecology has seen a major expansion in the last two decades. As the world rapidly urbanizes, human settlements constitute one of the few ecosystems on earth that are significantly increasing in their extent. As a result, interest from both the scientific community and society at large has turned its attention to the functioning of cities and their impacts on larger regions, gl...

rapid urbanization has brought environmentally, socially, and economically great challenges to cities and societies. to build a sustainable city, these challenges need to be faced efficiently and successfully. this paper focuses on the environmental issues and investigates the ecological approaches for planning sustainable cities through a comprehensive review of the relevant literature. the re...

1. Current views of anthropogenic environments emphasize the extreme novelty of urban and industrial ecosystems. Proponents of reconciliation ecology argue that we need to use such habitats to conserve biodiversity, given the inadequacy of natural reserve systems. 2. Some of the harshest anthropogenic ecosystems may be able to support indigenous biodiversity due to their structural or functiona...

Urban land-use change, the conversion of agricultural and natural ecosystems to human settlements, has become an important component of global change. Virtually all of the projected increase in the world’s population is expected to occur in cities so that by the year 2007 more than half of the global population is expected to live in urban areas (United Nations 2004). Yet, urban settlements and...

An ecosystem is traditionally defined as a community of organisms functioning as an ecological unit in nature. Ecologists often study sites as far away from human influence as possible to get closer to nature. Likewise, when urban educators teach ecology, they often take their students outside the cities to study nature's ecosystems. However, leaving the city limits may no longer be necessary a...

Urban ecosystems are carrying an extinction debt. Mitigating this debt will require the development of a predictive framework that improves our understanding of the factors causing decline of native biodiversity in urban areas. I argue that nitrogen is a common currency around which such a predictive framework could be built. I first summarise the evidence that shows the probable extent of nitr...