Effects of grazing on soil respiration in typical Leymus chinensis steppe in Inner Mongolia
Using the static opaque enclosed chamber, the seasonal dynamics and annual to-tal amount of soil respiration in fence-enclosed and grazed Leymus chinensis steppes of Xi-lin River basin in Inner Mongolia, China, were compared in 2007, and its environmental driving factors were analyzed. The results showed that there was no significant difference between fenced and grazed plots in seasonal dynamics of soil respiration, but the grazed decreased the annual variation range of soil respiration. In growing season, the soil respi-ration rates were much lower in the grazed plot than in fence-enclosed plot, and annual soil respiration decreased by 33.95 % due to the grazing, but in the non-growing season, there was little difference in soil respiration between the two sites. In a year round, soil respira-tion was positively correlated with the temperature, the Q10 values in fence-enclosed and grazing plots were 3.89 and 2.59, respectively, and grazing decreased the sensitivity of temperature sensitivity of soil respiration, while in the growing season, soil respiration was significantly related to soil moisture. In the fence-enclosed plot, soil respiration was affected by the soil water content at a depth of 0-10 era, and the change of 0-10 cm soil water content accounted for 87.4% of variation of soil respiration. In the plot with graz-ing, soil water contents at depths of 10-20 and 20-30 cm were the main factors affecting the change of soil respiration, and the two factors could explain 74.9% of the total varia-tion of soil respiration.
NETL
NSTL
万方数据
维普
