Chin J Plan Ecolo ›› 2015, Vol. 39 ›› Issue (11): 1044-1052.DOI: 10.17521/cjpe.2015.0101

Special Issue: 稳定同位素生态学

• Orginal Article • Previous Articles     Next Articles

Foliar stable carbon isotope ratios of Phragmites australis and the relevant environmental factors in marsh wetlands in Tianjin

CHEN Qing, WANG Yi-Dong, GUO Chang-Cheng, WANG Zhong-Liang*()   

  1. Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin 300387, China
  • Received:2015-05-27 Accepted:2015-10-04 Online:2015-11-01 Published:2015-12-02
  • Contact: Zhong-Liang WANG
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    # Co-first authors


Aims Phragmites australis marshes in Tianjin play an important role in ecosystem functioning. Wetlands of Tianjin municipality have been suffering from serious nitrogen loading, salinization and water shortage. The foliar stable carbon isotope ratio (δ13C) is a good parameter which records environmental change information associated with the plant growth process, and reflects physiological and ecological responses of plants to environment changes. The objective of this study is to investigate the effects of environment stress on the leaf δ13C of P. australis in marsh wetlands in Tianjin municipality.Methods This study was conducted in Qilihai, Beidagang, and Dahuangpu marsh wetlands. We investigated the foliar δ13C of P. australis and sediment properties, and evaluated the relationships between the foliar δ13C and sediment environmental factors. Important findings 1) Foliar δ13C ranged from -26.3‰ to -23.6‰, with an average value of -25.8‰. 2) Sediment water and nitrogen status were the important factors affecting reed foliar δ13C. Foliar δ13C was negatively correlated to sediment relative water content, and positively correlated to sediment total nitrogen and available nitrogen content. In contrast, foliar δ13C was not significantly correlated to sediment salinity and phosphorus content. 3) Leaf δ13C were significantly positively correlated with leaf nitrogen content, and negatively correlated with leaf carbon and nitrogen ratio across all site. However, these relationships were not detected due to the wetland drainage at Qilihai site in August. Wetland drainage changed the plant water and nitrogen balance, and further affected water and nitrogen utilization strategies of P. australis. Moreover, wetland drainage had stronger effects on these processes than nitrogen loading and salinization.

Key words: stable carbon isotope ratio, nitrogen, salinity, wetland drainage, Phragmites australis