Chin J Plan Ecolo ›› 2017, Vol. 41 ›› Issue (4): 461-470.DOI: 10.17521/cjpe.2016.0231

Special Issue: 生态化学计量

• Orginal Article • Previous Articles     Next Articles

C, N and P stoichiometry in different organs of Vitex rotundifolia in a Poyang Lake desertification hill

Hong-Yan ZHOU1, Qin WU1, Ming-Yue CHEN1, Wei KUANG1, Ling-Ling CHANG1, Qi-Wu HU1,2,*()   

  1. 1School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China
    and
    2Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education (Jiangxi Normal University), Nanchang 330022, China
  • Received:2016-07-05 Accepted:2017-02-14 Online:2017-04-10 Published:2017-05-19
  • Contact: Qi-Wu HU

Abstract:

Aims The objectives were to clarify the responses of C, N and P stoichiometry of Vitex rotundifolia to desertification, and determine the C, N and P stoichiometric relationships among the organs.
Methods In this study, different organs (e.g. flowers, leaves, twigs, creeping stems, fine roots) of V. rotundifolia were sampled along a desertification gradient in a typical Poyang Lak sandy hill. Subsequently, C, N and P contents of various organs were measured.
Important findings The results showed nutrient contents in different organs ranged from 386.28 to 449.47 mg·g-1 for carbon, 11.40 to 25.37 mg·g-1 for nitrogen and 0.89 to 1.54 mg·g-1 for phosphorus, respectively. C, N and P contents differed significantly among the five organs. The maximum N and P content were found in flowers, whereas the minimums were observed in twigs and creping stems. Moreover, desertification intensity only significantly affected C, N and C:P. C:N and N:P ratios maintained relatively stable. Except N:P, the other nutrient elements and associated stoichiometry significantly differed among the organs. Hence, organs, rather than desertification intensity mainly controlled the C, N and P content and their stoichiometry variability. Although there was a positive correlation between mass-based N content (Nmass) and P content (Pmass) across the three desertification zones, the Nmass-Pmass relationship in V. rotundifolia did not shift. Irrespective desertification intensity and organs, N:P stoichiometry of V. rotundifolia was well constrained. In addition, significant correlations of C, N and P contents among organs were mainly found in the above-ground parts, especially between twigs and creeping stems.

Key words: Poyang Lake, desertification hill, plant organ, nutrient, stoichiometry