**Acknowledgements**

We are thankful for the useful discussions with Professors Huiling Yuan (Nanjing University), Weidong Guo (Nanjing University), and Zhaohua Wu (FSU) on the relevance of this research to environmental change and societal adaptations. We also thank Professors Mervyn Lynch (Curtin University), Zhaomin Wang (Hihai University), and Xiangbai Wu for providing constructive comments on the aspects of the manuscript.
