Longitudinal variation characteristics of stable isotope ratios of suspended particulate organic matter in the headwaters of the Qingjiang River, China

Knowledge and Management of Aquatic Ecosystems

Zhong Ping¹  Liao Mingjun²  Gao Jian²  Zehui Zhang²  Jiao Yiying²  Cheng Yang² 

[1] Department of Ecology and Institute of Hydrobiology, Tropical and Subtropical Aquatic Ecological Engineering Center of the Ministry of Education of China, Jinan University;Hubei Province Key Laboratory of Ecological restoration of Lakes and Rivers and Algal Utilization, School of Civil and Environmental Engineering, Hubei University of Technology;

关键词: suspended particulate organic matter;    stream;    stable isotope;    anthropogenic pollution;    tailwater;   

DOI  :  10.1051/kmae/2021007

来源: DOAJ

【 摘 要 】

To determine the sources and characteristics of suspended particulate organic matter (SPOM), the spatial distribution of carbon and nitrogen and their isotopic values (δ13C and δ15N) were measured from upstreamto downstream (i.e. site 1 to site 4) in the head waters of the Qingjiang River in central China. The mean annual SPOM δ15N and δ13C values varied between sites but exhibited a unimodal pattern. The mean annual δ15N increased from site 1 (2.5‰) to 3 (5.3‰), followed by a major decrease to 2.2‰ at site 4. Furthermore, the mean annual δ13C varied unimodally, being the most positiveat sites 1 (−21.6‰) and 4 (−22.8‰) followed by sites 2 (−24.5‰) and 3 (−26.4‰). In particular, the mean SPOM δ15N and δ13C in the tailwaters from a domestic wastewater treatment plant, which was located approximately 0.3 km upstream of site 4, were 2.2‰ and −25.6‰, respectively. The SPOM C/N values from stream water at site 4 (8.5 ± 1.5) and tailwater (6.2 ± 0.9) were similar. Collectively, the results suggested that wastewater treatment plant tailwater influenced the stable isotope values of SPOM in the stream and affected the variation trendfrom upstream to downstream.

【 授权许可】

Unknown