Characteristics of Soil Respiration on Horqin Meadow

Soil respiration was measured on Horqin meadow ecosystem during 2010 using a portable photosynthesis system(Li-6400).A model between soil respiration and soil temperature measured synchronously was set up.The results showed that diurnal variation of soil respiration was a one-humped curve,the highest value occurred at about 14:00,the lowest value occurred in the early morning.Soil respiration was the highest in summer,varied between 6.70 and 15.29 μmol·m-2·s-1,the lowest in winter,varied from 0.02 to 3.21 μmol·m-2·s-1.The relationship between soil respiration and soil temperature at 5 cm in depth was exponentially correlated.Soil temperature can indicate 81.9% of soil respiration on the meadow ecosystem.The Q10 value was 2.92.The ratio of root respiration to soil respiration was 6.6%~29.4%,with an average of 18.9%.