title: [Transported fluxes of the riverine carbon and seasonal variation in Pearl River basin].
abstract: The riverine carbon flux is a critical component of global carbon cycle. Riverine water samples were collected from eleven hydrometric stations in the main stream of Pearl River and its tributaries during April and July, 2012. The samples were analyzed for the space and seasonal distribution characteristics of the riverine suspended substance and carbon compositions. Carbon fluxes and erosion modulus of Pearl River basin were also estimated in Boluo, Shijiao, Gaoyao, namely Dongjiang, Beijiang, Xijiang, in these two hydrological seasons. The results showed that the total suspended substance (TSS) and organic carbon, including total particulate organic carbon (POC) and dissolved organic carbon (DOC) have higher concentration in the high-water season than that in the normal-water season. Dissolved inorganic carbon (DIC) has an overwhelming concentration compared to other carbon compositions in Pearl River basin. The DIC concentration shows an order of Xijiang, Beijiang and Dongjiang from high to low. The percentage of allogenic POC in Xijiang, Beijiang and Dongjiang are 78%, 72%, 26%, respectively, and C3 plants are the main sources of allogenic POC in those three tributaries. The transported fluxes of TSS, total carbon (TC), POC, particulate inorganic carbon (PIC), DOC, DIC, total particulate carbon (TPC) and total organic carbon (TOC) are 134 x 10(12),12.69 x 10(12), 2.50 x 10(12), 1.01 x 10(12), 1.13 x 10(12), 8.05 x 10(12), 3.51 x 10(12) and 3.65 x 10(12) g x a(-1), respectively, and the erosion modulus of those compositions are 309 x 10(6), 28.98 x 10(6), 5.75 x 10(6), 2.27 x 10(6), 2.56 x 10(6), 18.4 x 10(6), 8.02 x 10(6) and 8.31 x 10(6) g x (km2 x a)(-1), respectively. Compared with average values of global large rivers, the erosion modulus of DOC, POC, and TOC in Pearl River basin are higher than the corresponding values.
authors.affiliation: Karst Dynamics Laboratory, Ministry of Land and Resources & Guangxi Zhuang Autonomous Region, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China. Zhangliankai@karst.ac.cn
authors.forename: Lian-Kai
authors.initials: LK
authors.lastname: Zhang
authors.forename: Xiao-Qun
authors.initials: XQ
authors.lastname: Qin
authors.forename: Hui
authors.initials: H
authors.lastname: Yang
authors.forename: Qi-Bo
authors.initials: QB
authors.lastname: Huang
authors.forename: Peng-Yu
authors.initials: PY
authors.lastname: Liu
mesh_terms: D002244:Carbon / Q000032:analysis*; D017554:Carbon Compounds, Inorganic / Q000032:analysis; D002681:China; D004784:Environmental Monitoring; D052638:Particulate Matter; D045483:Rivers / Q000737:chemistry*; D012621:Seasons; D014874:Water Pollutants, Chemical
chemical_list: D017554:Carbon Compounds, Inorganic; D052638:Particulate Matter; D014874:Water Pollutants, Chemical; D002244:Carbon