Coping with an urbanising world: interdisciplinary research towards sustainability Jingzhu Zhao 1 , Yong-Guan Zhu 1 , Guofan Shao 2 and David Ness 3 1 Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China 2 Department of Forestry and Natural Resources, Purdue University, West Lafayette, USA 3 Institute for Sustainable Systems and Technologies, University of South Australia, Adelaide, Australia In response to the great challenges of rapid urbani- sation and increases in the need to build ‘harmoni- ous’ cities, i.e. cities with a high quality of life, the Chinese Academy of Sciences, in collaboration with the International Journal of Sustainable Development and World Ecology, has taken the lead by organising the 1st Xiamen International Forum on Urban Environment, held in Xiamen, China, between November 28 and 29, 2007. The forum attracted almost 100 participants from around the world. This introductory paper summarises the key topics presented in this special issue and associated supplement on urban sustainability and environ- mental management. Urbanisation is generally considered as a posi- tive process of societal development; however, rapid urbanisation is also one of the challenges facing the world in the twenty-first century. The twentieth century witnessed the most rapid urbani- sation in human history, and by 2007, more than half of the people on Earth lived in cities. However, urbanisation has negative impacts, particularly as a cause of environmental pollution derived by inten- sive energy consumption and material flows (‘mate- rial metabolism’), and leading to dramatic changes in land use, loss of biodiversity, habitat fragmenta- tion and a decline in ecosystem services. Therefore, studies on urbanisation and its environmental consequences have become urgent and are a focal topic for the scientific community worldwide. Urban environmental research should promote sustainability of the urban environment and develop harmonious urban systems through part- nerships with urban planners and policymakers. Contrary to the intensity of urban or urbanisation studies, there have been a relatively small number of urban environmental studies that have explicitly connected ‘urbanisation’ with ‘environment’. The Forum was intended to promote integrated studies on the urban environment by providing a commu- nication platform to interested scholars on urban environment around the world. URBAN ENVIRONMENTAL MANAGEMENT The study of urban environmental management involves assessment of urban systems and linkages to policymaking processes. The paper by Ness addressed urban infrastructure and resource pro- ductivity (a term related to eco-efficiency) (Ness 2008), with particular reference to the develop- ment of a ‘circular’ economy in China, i.e. with efficient recycling of materials. He considered the contribution of transport, energy, water and the built infrastructure to resource consumption, greenhouse gas emissions and the ecological foot- print and ways in which China can move towards a Factor 10 improvement in resource productivity. Zhao and colleagues took a wider view and looked Correspondence: Jingzhu Zhao, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361003, China. Email: jzhao@rcees.ac.cn 284 International Journal of Sustainable Development & World Ecology 15 (2008) 284–287 DOI 10.3843/SusDev.15.4:1