China has the world's largest area of rice paddy. As such, emissions o
f methane (CH4) from China are of interest in understanding the global
CH4 budget. Using a simplified process-based methane emission model a
nd a georeferenced database, CH4 emission rates from 329 defined agric
ultural zones in China, where rice production occurred, were estimated
in this study. The calculated daily CH4 emission rates ranged from 0.
12 g m(-2) to 0.70 g m(-2) with an average value of 0.44 g m(-2). The
annual CH4 emissions varied between 25 g m(-2) and 80 g m(-2). On aver
age across the whole rice growing area in China, 59.9 g m(-2) CH4 was
released annually. Total CH4 emission was 16.2 Tg year(-1) (1 Tg = 10(
12) g). Although the model and supporting database used had some uncer
tainties, these results demonstrated the ability to assess CH4 emissio
ns at the regional level within the framework of climate-plant-soil in
teractions.