Using complex network analysis to assess the ecological security network
for a rapid urbanization region in China
Abstract
A sound ecological security network (ESN) promotes the interconnection
of ecological sources, improves the pattern of ecological security, and
alleviates the degradation of an ecosystem. Rapid urbanization and land
use changes may lead to serious fragmentation and islanding of landscape
patches and further to deep disturbance of regional ESNs. However, most
studies in the recent years focused on the methodological development of
ESN identification, reconstruction, and optimization, but lacked the
systematic assessment of the network after its construction. The purpose
of this study is to use complex network analysis to systematically
assess the constructed ESN for the urban agglomeration around Hangzhou
(UAHB), a rapid urbanization region in China. By integrating landscape
ecology theory, graph theory, and complex network analysis, we
abstracted the ESN into a topological network and developed an index
system to assess the abstracted network, which was based on the
structural elements of the topological network (nodes, edges, and the
overall network). Our results show that the connectivity and stability
of the UAHB’s ESN have been improved in the last 20 years, although
isolated nodes are still existing in the ESN. Our study also shows that
the network’s robustness under human disturbance has been affected more
than that under non-human disturbance. Finally, we proposed five
optimization strategies from the perspective of topological structure
and ecological function to maintain a sustainable and well-protected
ecological system.