Abstract: Among the methods of measuring forest soil respiration, infrared CO₂ analysis is the optimal one so far. Comparing with empirical model, the process-based model in simulating the production and transportation of soil CO₂ has the advantage of considering the biological and physical processes of soil respiration. Generally, soil respiration is positively correlated with soil temperature and moisture, but there are still many uncertainties about the relationships between soil respiration and forest management activities such as firing, cutting, and fertilization. The relationships of soil respiration with vegetation type and soil microbial biomass, as well as the spatial heterogeneity of soil respiration, are the hotspots in recent researches. Some issues and future development in forest soil respiration research were discussed in this paper.

Key words: Ecological risk, Ecological health, Ecological security, Assessment method, Index system