Abstract:

Soil is an important component of terrestrial ecosystems, research on soil carbon storage in the carbon cycle and global change is of great significance. Based on the double grid, large density and high accuracy data obtained from previous multi-purpose regional geochemical survey in 2003, the carbon density and storage of 0-20 cm, 0-100 cm and 0-160 cm soil in Shandong Province were estimated, meanwhile, a systematic research was conducted on the temporal and spatial variation of soil organic carbon (SOC) density and storage, as well as the potential capacity of carbon sequestration. It was found as follows. (1) The SOC density in 0-20 cm, 0-100 cm, and 0-160 cm soil layers of Shandong Province were 2.22 kg/m², 7.64 kg/m², and 10.09 kg/m², respectively, which were all lower than the national average levels. (2) The distribution of SOC density in Shandong Province generally presented that the coastal area is low, the plain area in northwest part and hilly area in east part is medium, and the mountain area in middle-south part is high. (3) Compared with the data obtained from the second soil survey in 1985, SOC density of top soil increased from 1.43 kg/m² to 2.22 kg/m². SOC storage of whole land territory in Shandong, totally 157,000 square kilometers, increased from 226.41 Mt to 350.65 Mt, with a net increase of 124.24 Mt, which indicates that the SOC density is growing at a rate of 0.044 kg/(m²·a), and representing a “carbon sink” effect. According to preliminary estimate, there is another 505.23 Mt carbon sequestration potential.

Key words: soil carbon density, soil carbon storage, temporal and spatial variation, carbon sequestration potential, Shandong Province