Location: Commodity Utilization ResearchTitle: Three-year field observation of biochar-mediated changes in soil organic carbon and microbial activity
|MING, LI - Chinese Academy Of Sciences|
|WANG,, YIMIN - Hohai University|
|LIU, MING - Chinese Academy Of Sciences|
|LIU, QI - Chinese Academy Of Agricultural Sciences|
|XIE, ZUBIN - Chinese Academy Of Sciences|
|LI, ZHONGPEI - Chinese Academy Of Sciences|
Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/20/2018
Publication Date: 3/8/2019
Citation: Li, M., Wang, Y., Liu, M., Liu, Q., Xie, Z., Li, Z., Uchimiya, M., Chen, Y. 2019. Three-year field observation of biochar-mediated changes in soil organic carbon and microbial activity. Journal of Environmental Quality. 48(3):717-726. https://doi.org/10.2134/jeq2018.10.0354.
Interpretive Summary: Although biochar had been extensively investigated by both federal and academic sectors to benefit agricultural production, many reports are not reproducible in the field. This study conducted 3 year field experiment to understand the inter-dependency between the soil microbial community, nutrient availability, and organic carbon structure of biochar-amended soils. Results indicate complex yet predictable relationships between the changes in microbial community structure (estiamted by the phospholipid fatty acids assay) and lability (sensitivity to microbial decomposition) of soil organic carbon.
Technical Abstract: Although biochar is considered a promising carbon sequestration agent, long-term field experiments are lacking to assess the effects of biochar addition on the soil organic carbon and microbial community. Corn straw feedstock and biochar were applied to a sandy loam soil under rice-wheat rotation system for three consecutive years to investigate the organic carbon (humic and fulvic) distribution within aggregates (by density fractionations), soil microbial biomass, enzyme activity, and community structure. Biochar (12.0 t ha-1) decreased the fulvic acid fraction by 14.5%, and increased the free-light (FLC), intra-aggregate (IAC) and organo-mineral (OMC) fractionations by 6.66, 0.53 and 3.27 g kg-1, respectively. Neither straw nor its biochar influenced the soil microbial biomass carbon/nitrogen contents or the activities of urease, sucrose and acid phosphatase. Phospholipid fatty acids (PLFAs) assay suggested that 6.0 t ha-1 straw slightly enrich the abundance of actinobacteria in soil, while biochar (6.0 and 12.0 t ha-1) mainly promoted the growth of gram-positive bacteria, fungi and general bacteria groups. Compared to the straw biomass, the same amount of biochar (6.0 t ha-1) increased pH, SOC, total N (TN), available P (AP) and available K (AK). Multivariate analysis results indicated that soil pH, SOC, TN, AP, FLC and FA significantly influence the structure of soil microbial community (P<0.01). We concluded that biochar amendment to soil bring about changes of OC distribution within different soil fractions, and alter the status of soil chemical properties, both of which lead to the shifts of soil microbial profile.