title: Fertilization increases paddy soil organic carbon density.
abstract: Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon (SOC) sequestration. We sampled soils from a long-term (25 years) paddy experiment in subtropical China. The experiment included eight treatments: (1) check, (2) PK, (3) NP, (4) NK, (5) NPK, (6) 7F:3M (N, P, K inorganic fertilizers+30% organic N), (7) 5F:5M (N, P, K inorganic fertilizers+50% organic N), (8) 3F:7M (N, P, K inorganic fertilizers+70% organic N). Fertilization increased SOC content in the plow layers compared to the non-fertilized check treatment. The SOC density in the top 100 cm of soil ranged from 73.12 to 91.36 Mg/ha. The SOC densities of all fertilizer treatments were greater than that of the check. Those treatments that combined inorganic fertilizers and organic amendments had greater SOC densities than those receiving only inorganic fertilizers. The SOC density was closely correlated to the sum of the soil carbon converted from organic amendments and rice residues. Carbon sequestration in paddy soils could be achieved by balanced and combined fertilization. Fertilization combining both inorganic fertilizers and organic amendments is an effective sustainable practice to sequestrate SOC.
authors.affiliation: Institute of Environmental Science and Technology, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China.
authors.forename: Shao-xian
authors.initials: SX
authors.lastname: Wang
authors.forename: Xin-qiang
authors.initials: XQ
authors.lastname: Liang
authors.forename: Qi-xiang
authors.initials: QX
authors.lastname: Luo
authors.forename: Fang
authors.initials: F
authors.lastname: Fan
authors.forename: Ying-xu
authors.initials: YX
authors.lastname: Chen
authors.forename: Zu-zhang
authors.initials: ZZ
authors.lastname: Li
authors.forename: Huo-xi
authors.initials: HX
authors.lastname: Sun
authors.forename: Tian-fang
authors.initials: TF
authors.lastname: Dai
authors.forename: Jun-nan
authors.initials: JN
authors.lastname: Wan
authors.forename: Xiao-jun
authors.initials: XJ
authors.lastname: Li
mesh_terms: D002244:Carbon / Q000032:analysis* / Q000737:chemistry*; D005308:Fertilizers; D009930:Organic Chemicals / Q000737:chemistry*; D012275:Oryza / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*
chemical_list: D005308:Fertilizers; D009930:Organic Chemicals; D012987:Soil; D002244:Carbon