KMS Chongqing Institute of Green and Intelligent Technology, CAS
| Developing and optimizing ecological networks for the towns along the three gorges reservoir: A case of Kaizhou new Town, Chongqing. | |
Jia, Zhen-Yi1,2; Chen, Chun-Di2 ; Tong, Xiao-Xiao2; Wu, Sheng-Jun2; Zhou, Wen-Zuo1
| |
| 2017 | |
| 摘要 | Habitat fragmentation and loss have become the major threats to local biodiversity pro- tection and regional ecosystem integrity. Developing urban ecological networks and improving con- nectivity between habitats could facilitate energy and matter fluxes, species dispersal, genetic ex- change and many other ecological processes, and further relieve the ecological environmental cri- sis in cities. With rapid urbanization in the Three Gorges Reservoir region, natural area fragmen- tation and habitat loss are inevitable. Taking Kaizhou New Town as an example, our study built the urban ecological networks by least-cost path modeling and GIS technology in order to facilitate the establishment of native tree species. The best threshold for urban ecological networks was ob- tained by the verification from graph theory functioning index. Finally, the priority of habitat pro- tection and restoration was determined after evaluating the importance grades of patches/ connec- tivities. We set a native tree, Pterocarya stenoptera as a surrogate species and used the habitat suitability assessment values to build the cost surface for least-cost model by Linkage Mapper Toolist. The observed maximum seed dispersal distance (300 m) of P. stenoptera was used as the distance threshold for network analysis. 75 target patches were selected as habitat sources to de-velop networks. Under the 300 m distance threshold, 98 links were simulated for the network, and were grouped into six grades according to their importance values. We found the links with higher importance values almost all existed along the bank between the Pengxi River and Hanfeng Lake. Among these, the most important link was between Hanfeng Lake Park and Kaizhou Plan- ning Institute; the second important link was located on both sides of the highway bridge over the Pengxi River. The integral index of connectivity of the whole landscape would be reduced by 19.1% if the two links were removed. Additionally, we found that the importance of the link was not significantly correlated with the important values of the two patches that the link connected. Link importance may also relate to the shape and spatial location of patches. Based on these re- sults, we proposed some network improvement strategies. This study combined least-cost path analysis and a graph-theoretical algorithm and provided a scientific, reliable reference for plan-ning and construction of urban ecological networks. © 2017, editorial Board of Chinese Journal of Ecology. All rights reserved. |
| DOI | 10.13292/j.1000-4890.201703.011 |
| 发表期刊 | Chinese Journal of Ecology
 |
| ISSN | 10004890 |
| 卷号 | 36期号:3页码:782-791 |
| 语种 | 中文 |
