title: Molecular biomarkers for sources of organic matter in lacustrine sediments in a subtropical lake in China.
abstract: N-alkanes distributions and stable isotopic compositions (δ(13)C and δ(15)N) in the lacustrine sediments of Shijiu lake were measured to assess whether biological source information was recorded in the molecular biomarker. Results showed regular unimodal n-alkanes distribution in range of C16-C33 with strong predominance of odd-numbered n-alkanes, maximizing at C29. The δ(15)N for SON were uniformly low, ranging from -6.7‰ to 3.8‰ and C/N ratios ranged from 6.6 to 10.0, suggesting that most of organic matter was influenced by terrestrial characteristics of the watershed. The δ(13)C for C27 to C31n-alkanes and for SOC varied from -32.9‰ to -26.6‰ and -23.4‰ to -21.6‰, respectively, falling within the range of corresponding n-alkanes in leaves mainly from C3 land plants. The values of C/N, CPI, OEP, ACL and C27/C31 exhibit similar temporal changes with the primary production, showing enhanced eutrophication resulted from increased anthropogenic activities in Shijiu lake from 1852 to 2010.
authors: School of Geography Science, Nanjing Normal University, 1 Wenyuan Road, Qixia, Nanjing 210046, China. wangyanhua@njnu.edu.cn
authors: Yan-Hua
authors: YH
authors: Wang
authors: Hao
authors: H
authors: Yang
authors: Xia
authors: X
authors: Chen
authors: Ji-Xiang
authors: JX
authors: Zhang
authors: Jie
authors: J
authors: Ou
authors: Biao
authors: B
authors: Xie
authors: Chang-Chun
authors: CC
authors: Huang
mesh_terms: D015415:Biomarkers / Q000032:analysis*; D002247:Carbon Isotopes / Q000032:analysis; D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D005068:Eutrophication; D019015:Geologic Sediments / Q000737:chemistry*; D060106:Lakes / Q000737:chemistry*; D009587:Nitrogen Isotopes / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D015415:Biomarkers; D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D014874:Water Pollutants, Chemical