DING Wei1,2, CHEN Jinan2, YANG Haiquan2,3, SONG Yilong2,3, TAO Hongbo1,2, LUO Jing4
(1. College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, China;
2.State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang , 550081, China;
3.University of Chinese Academy of Sciences, Beijing 100049, China;
4.China Aerospace Construction Group Limited Company, Beijing 100071, China)
Abstract:In this study, δ13C values and concentrations of dissolved organic carbon (DOC) and particle organic carbon (POC) of soils, plants, and inflow water were measured to investigate the spatial distribution, source and controlling factors of the organic carbon in Fuxian Lake, Yunnan Province. The results showed that the inflow waters had high DOC concentrations, ranging from 2.79 to 38.02 mg/L, while the concentration of DOC was evidently higher in the west (19.20 mg/L) and north (13.82 mg/L) than that in the east (3.37 mg/L). POC concentrations in the inflow waters were significantly low, ranging from 0.22~2.68 mg/L, while the POC concentration was higher in the north (0.84 mg/L) than that in the west (0.56 mg/L) and east (0.40 mg/L). The living sewage and widespread pollution from the overuse of fertilizers and pesticides in the drainage basin caused the high DOC concentrations in the rivers. The δ13CDOC value ranged from -12.6‰ to-25.5‰ and displayed slightly decreased trend with the increase of DOC contents, which indicated the DOC in the rivers was of a mixed origin of soils erosion, nonpoint source pollution and sewage discharge. The δ13CPOC of inflow waters varied mainly in the range of -23.23‰ ~-26.96‰, far from the range of endogenous particulate organic matters, while consistent with the soil and plant of the basin.This indicated the POC was mainly derived from soil erosion and plant fragments input.
Key Words:Fuxian Lake; inflowing river; organic carbon; carbon isotope; distribution characteristics
EARTH AND ENVIRONMENT Vol. 44, No.3 Tot No.311, 2016, Page 290-296