Abstract:Worldwide urbanization occurred since the industrial revolution, and this trend is expected to last in the coming decades. Dramatic land use/ cover change (LUCC) driven by urbanization has been the most prominent force in the degradation of the structure and function of the ecosystems, thus undermining the capacity of the ecosystems to sustain the development of human society. Therefore, LUCC driven by urbanization has recently attracted much attention.
Locally and globally, combined with the knowledge of socio-economic and biophysical sciences, modelling LUCC and its environmental impacts can be employed as a useful tool to assess the adverse or favourable impacts on the ecosystem functions, which are the key foundation for the sustainability of human society and balance of global ecosystems. So far many efforts have been made to enhance the effectiveness of LUCC models. However, due to the complexity of the interactive systems, it is still difficult to understand, explain, and predict the dynamics and trends of LUCC and its possible ecological consequences. Although there is the close correlation between LUCC and urban ecological security, and the driving forces of land use changes have been well documented, whereas papers of impacts of land use changes on urban ecological security are scarce.
Based on the review of published papers on LUCC and urban ecological security (UES), the concept of UES is redefined. Two stages of studies on UES have also been identified: the early qualitative research and the current quantitative research. Furthermore, three aspects worth further studies are emphasized:(1) Due to the incomplete theories of UES, the role of LUCC in the integrated assessment of UES was ignored .Therefore, it′s still difficult to use LUCC as the guidance to the urban planning and construction; (2) Methods including information technique, mathematical model, GIS, Environmental impact assessment(EIA), Ecological risk assessment (ERA) , and policy analysis were seldom incorporated in the studies of the ecological effects of urban land use. In practice, dynamical simulation and multi-scenarios analysis are expected to serve as the basis for decision-making. Also, the effectiveness of the above integrated methods needs to be assessed to produce the optimized paradigm for the study on urban security; (3) Detection of land use dynamics, mechanism of driving forces, and ecological responses were seldom employed in the comprehensive studies on regional ecological security and ecological control of urbanization. Therefore, such studies have limited practical significance. Finally, future trends of LUCC and urban security studies are discussed : (1) Close linkage of LUCC and accompanied ecological consequences at different levels should be achieved, given the widely adopted LUCC monitoring networks by national and international agencies; (2) Application of integrated methods, including GIS, RS, EIA, ERA, spatial analysis, economic models, metabolism models, etc., should be developed on the basis of explicit case studies ; (3) Based on the theories and principles of interdisciplinary sciences, the detailed and rational frameworks for the evaluation methods and indicator systems should be developed .