Demands and Key Scientific Issues in the Synthesis Research on Regional Terrestrial Ecosystem Carbon Budget in China

Process mechanisms of carbon budget and carbon cycle in terrestrial ecosystems are the research hotspots in analyzing the causes of global climate change,forecasting the climate change trend,and making mitigation and adaptation countermeasures,which have attracted broad attention from the scientific community and international community.In this paper,we review the history of the research on the carbon budget and carbon cycle process in Chinese terrestrial ecosystems;summarize the main characteristics of each development stage.Based on the review,we discuss the demands for carrying out the systhesis research on regional terrestrial ecosystem carbon budget in China from the aspects of science and technology and society,bring forward the main existing problems,and explore the key scientific issues in related fields.The paper analyzes the importance for carrying out the synthesis research on regional terrestrial ecosystem carbon budget in China from various aspects such as socio-economic development,ecosystem management,and eco-security as well.Simultaneously,the paper points out that,in China,we are still lack of practical investigation data of carbon budget for various ecosystem types,lack of data integration at national scale,lack of modelling tools that can be used in carbon accounting and assessment,and no information system platform has been developed for national carbon source/ sink accounting,assessment,authorization and decision making.Through the above analysis,we think that,in order to enhance the innovation capacity in the area of ecosystem and global change in China,to provide fundamental theory and advanced technology for national ecosystem and greenhouse gases management,more emphasis should be placed on the following frontier fields,such as the coupling relationships among carbon-nitrogen-water cycles in terrestrial ecosystems and their response and adaptation to global climate change,ecological stoichiometry characteristics of carbon-nitrogen-phosphor and their environmental impact,and the biological regulation mechanisms of the processes of carbon-nitrogen-water coupling cycles as well.