Professor Liu Jianguo has been engaged in comprehensive research on ecology and social sciences and policies for a long time, including sustainable development, conservation biology, the relationship between human beings and nature, the impact of human activities on the environment and biodiversity (such as giant pandas and birds), system models and simulations, etc. He is interested in seemingly unrelated issues, such as divorce and environmental impact, the increase of family number and biodiversity hotspots, and the complexity of the coupling system between man and nature. The rapid development of China's economy has brought great challenges to the natural environment, and Professor Liu Jianguo is particularly keen on the study of China's sustainable development strategy. Professor Liu Jianguo founded and led the International Human-Nature Coupling System Research Network (CHANS-Net), and presided over dozens of interdisciplinary comprehensive research projects funded by government agencies and international organizations such as the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA) and the National Institutes of Health (NIH). Many research results have been published in the world's top academic journals (more than ten articles have been published in British Nature and American Science), and have been widely reported by news media all over the world (such as new york Times, Wall Street Journal, CNN, Associated Press, BBC, Time Weekly, China Xinhua News Agency, and China CCTV, etc.). His research results provide an important basis for formulating policies and laws related to environmental protection, biodiversity protection and natural resources management.