The global soil respiration (R_s) was estimated to be 98 Gt C in 2008; and it increased by 0.1 Gt C yr^-1 between 1989 and 2008. This estimation implied a global R_s response to air temperature (Q₁₀) of 1.5. However, most of the carbon-climate models imply Q₁₀ of 2.0 to predict the future global heterotrophic respiration (R_h), resulting global R_h increases with climate warms at an average rate of 6.2% per degree, and the current carbon sink of terrestrial ecosystem probably convert to a carbon source after 2050.

Terrestrial ecosystems in East Asia represent various vegetation types including boreal, temperate and tropical forests, grasslands, deserts, and crop fields extending from the arctic circle to equator. Therefore, knowledge of the soil carbon budget of the terrestrial ecosystems in Asian region is essential to advance our understanding of global carbon cycle and prediction of the impacts of climate change. Since the mid-1990s, we have installed the multichannel automated chamber systems in tundra in west Siberia, boreal forest in Alaska, temperate and cool-temperate forests in Japan, Korea and China, tropical seasonal forest in Thailand, and tropical rainforest in Malaysia, for continuous measurements of soil CO₂ efflux. The ultimate objective of our aim is to estimate the soil carbon budget of Asian forest ecosystems as well as its response and feedback to the regional climate change.