Acta Geographica Sinica ›› 2015, Vol. 70 ›› Issue (7): 1052-1067.doi: 10.11821/dlxb201507003

• Ecology and Environment • Previous Articles     Next Articles

Urban landscape ecological risk assessment based on the 3D framework of adaptive cycle

Yanxu LIU(), Yanglin WANG(), Jian PENG, Tian ZHANG, Hai WEI   

  1. Laboratory for Earth Surface Processes, Ministry of Education, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
  • Received:2014-08-25 Revised:2015-03-16 Online:2015-07-20 Published:2015-07-20
  • Supported by:
    National Natural Science Foundation of China, No.41330747

Abstract:

As the city social-ecological system was regarded as the risk assessment target, a 3D framework of ecological adaptive cycle was built, which extended the landscape ecological risk assessment indicators to the potential-connectedness-resilience 3D criteria from the former landscape index level. Emphasis was placed on the principle of static spatial pattern with interactive dynamic trend from a geographical spatial analysis view. It was believed that the 3D framework could describe the pattern-process interaction with specific landscape elements much more clearly. Taking Shenzhen city as a study area, this study adopted the 3D framework of ecological adaptive cycle in building a landscape ecological risk assessment index system with the help of GIS spatial analysis method. Different scenarios were established based on the ordered weighted averaging (OWA) algorithm in the risk assessment. The results show that among the three scenarios, the concrete value of landscape ecological risk showed a similar distribution trend that the Dapeng Peninsula had the lowest landscape ecological risk in Shenzhen city; Yangtai Mountain and Bijiashan Park showed relatively low risks in the city area, even though the risks in each scenario were specifically different. This indicated that the choice of the specific threshold in "development" or "protection" largely depended on the city development strategy created by decision makers under current cognition. The emphasis of scenario tradeoff was extracting the risk and uncertainty interval rather than an optimal value. The development or protection methods through each of the specific planning objectives would be the ultimate goal of the ecological risk assessment at a regional scale. The evaluation in this study improved the landscape ecological risk assessment indices and methods based on the adaptive cycle concept, which reflected the spatiotemporal dynamics and exposure disturbed by human interference. Furthermore, the preference transform in OWA method reduced the uncertainty caused by the subjective risk assessment, which could improve the theoretical basis as well as maneuverability in urban planning. This study not only extended the landscape ecological risk assessment to spatial-temporal integration perspective, but also made a significant improvement in ecological risk assessment of landscape indicator system. Therefore, the results of this study could offer a powerful quantitative support for landscape development and protective measures effectively, such as city construction and demarcation of ecological control line.

Key words: urban landscape EcoRA, adaptive cycle, ordered weighted averaging, exploitation and protection, Shenzhen City