Maize root-induced change in soil organic carbon pools
2002
Liang, B. C. | Wang, X. L. | Ma, B. L.
Quantification of root or root-induced changes in soil organic C (SOC), water-soluble organic C (WSOC), and microbial biomass C (MBC) is important for understanding processes of soil C storage. A greenhouse study was conducted on a Bainsville loamy sand (Typic Hapludoll) to evaluate root or root-induced quantitative and compositional changes in various SOC pools by growing corn (Zea mays L.), a C₄ plant, on a historically C₃ soil. Significant shifts in ¹³C of SOC pools, most noticeably in WSOC and MBC were observed. During the course of a growing season, the proportion of C₄-derived C varied from 0 to 12.3% of whole SOC, from 0 to 30.7% of WSOC, and from 0 to 52% of MBC, indicating a major contribution of root or root-induced C to various soil C components, especially WSOC and MBC. The amount of C₄-derived C in the entire soil estimated by the ¹³C natural abundance (δ¹³C) was remarkably consistent with the amount of C₄-C retained in the soil microbial biomass, WSOC, and corn roots, suggesting that measurements of ¹³C of the entire soil following the shift of C₃ to C₄ plants can be used as an indirect measure of root or root-induced C pools during the growing period.
显示更多 [+] 显示较少 [-]