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.
Keywords: ecological security network; complex network;
connectivity assessment; robustness assessment; urban agglomeration
around Hangzhou Bay