Abstract:In this paper, in order to discuss the effects of removing/keeping litter on soil respiration(SR) in/out of the gaps, clearly put forward the major factors influencing SR under these situations, improve the managements, and keep sustainable development of Chinese fir plantation, 12 years-old Chinese fir plantations and their gaps in similar sites and with same managements at Fuzhou Baisha State-owned Forest were set up and chosen, respectively, to study SR differences, relationships between SR and other environments, SR fitting models in and outside of forest gaps under the circumstances of keeping or moving litter falls in the plots. SR, and soil surface temperature and moisture were measured in several fixed sample plots by Li-8100A during the fine days per month from March, 2014 to February, 2015 in order to analyze the month dynamic characteristics of SR, environment factors and the relations between the two with different carbon inputs in or out of the Chinese Fir forest gaps combining with variance analysis. The results showed that 1) the anural average values of SRs in and outside of Chinese fir plantations were 2.47 and 2.13 μmol m-2 s-1 respectively, and that it would decrease 22.89% and 25.89% respectively while removing the cover litter fall. In or out of the gaps of the forests, both the maximum values of SR appearing in July were (3.65±0.14) and (2.85±0.08) μ mol m-2 s-1 after removing litter respectively, and were (4.26±0.34) and (3.61±0.34) μmol m-2 s-1 by keeping litter, respectively. And the minimum ones contemporarily emerging in January were (0.9±0.04) and (0.83±0.03) μmol m-2 s-1 after taking off the liter respectively, and were (1.02±0.041) and (0.92±0.05) by holding litter respectively. 2) Soil temperature together with moisture could account for 68.63%-77.28% of the total SR totally; 3) the relationships between soil respirations and soil temperatures/moistures are significant correlations with large correlation coefficient in the depth less than 5cm in the soil; 4) all the two-factor models were better than the single-factor ones of soil temperature and moisture in explaining the dynamic variances of SR in/out the gaps in Chinese fir plantations; Soil sensitive coefficient (Q10) of SR when wiping off litters in/out Chinese fir forest were 1.39 and 1.37, respectively, which were not significant (P=0.634), while Q10 were 1.40 and 1.55 when keeping litters in/out of gaps in Chinese fir plantations, respectively, which were significant (P=0.010). The results could provide the thesis foundation for carbon flux and its mechanism in the ecosystem of Chinese fir plantation.