Chin J Plant Ecol ›› 2008, Vol. 32 ›› Issue (2): 402-407.DOI: 10.3773/j.issn.1005-264x.2008.02.018

• Research Articles • Previous Articles     Next Articles

RELATIONSHIP BETWEEN N AND P CONTENTS IN AQUATIC MACROPHYTES, WATER AND SEDIMENT IN TAIHU LAKE, CHINA

LEI Ze-Xiang1,2, XU De-Lan3, XIE Yi-Fa2, LIU Zheng-Wen2,4,*()   

  1. 1Department of Environmental Science and Engineering, Zhongkai University of Agriculture and Technology, Guangzhou 510225, China
    2Institute of Hydrobiology of Jinan University, Guangzhou 510632, China
    3Department of Environmental Engineering, Xuzhou Institute of Technology, Xuzhou, Jiangsu 221008, China
    4Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
  • Received:2006-11-20 Accepted:2007-09-29 Online:2008-11-20 Published:2008-03-30
  • Contact: LIU Zheng-Wen

Abstract:

Aims Our objectives were to 1) examine relationships between N and P contents in aquatic macrophytes, water and sediment in Taihu Lake, a eutrophic ecosystem, and 2) explore factors controlling N and P contents in plants in relation to plant characters, such as growth status and developmental stage.
Methods We selected 32 sampling sites in the emerging-plants-free water zone of Taihu Lake and collected plant samples twice with the quadrat method, sampled sediment with column-shaped samplers at different depths, and measured relevant parameters. Concentrations of total phosphorus and total nitrogen of sediment samples with and without macrophytes were measured with the Kjeldahl method and ICP-AES atomic absorption spectrometry, respectively, and those in tissues of aquatic plants were measured by Kjeldahl automatic N analyzer and molybdate-ascorbic colorimetric determination, respectively.
Important findings The N and P contents of tissues of submerged macrophytes were higher than floating-leaved macrophytes, and the nutrient contents were higher in May than in September. Significant correlations were found between the concentrations of N and P in plants and in water, but not in sediments. The N and P contents in plants were highly dependent on plant growth status and developmental stage. Our study provides the insight for the restoration of the eutrophic Taihu Lake ecosystem.

Key words: Taihu Lake, submerged macrophytes, floating-leaved macrophytes, contents of N and P, correlations