Chin J Plan Ecolo ›› 2012, Vol. 36 ›› Issue (5): 447-455.DOI: 10.3724/SP.J.1258.2012.00447

• Research Articles • Previous Articles     Next Articles

Effects of elevated CO2 concentration and N deposition on leaf element contents of major native tree species in southern subtropical China

LI Yi-Yong1,2*, HUANG Wen-Juan1,2, ZHAO Liang1,2, FANG Xiong1,2, and LIU Ju-Xiu1**   

  1. 1South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China;

    2Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2011-11-23 Revised:2012-02-17 Online:2012-05-01 Published:2012-05-04
  • Contact: LIU Ju-Xiu
  • Supported by:

    ;National Natural Science Foundation of China

Abstract:

Aims The effects of elevated atmospheric CO2 concentration and N deposition on terrestrial ecosystems and plants are the focus of international ecological study. Changes of nutrient element content in plants induced by atmospheric CO2 concentration and/or N deposition directly affect the productivity of forest ecosystems; however, few studies have examined this in subtropical China. Our purpose is to study the effects of elevated CO2 and N deposition on leaf element contents of major native tree species in southern subtropical China.
Methods Five tree species native in southern China were planted in model forest ecosystems. The species were exposed to elevated CO2 and N deposition in open top chambers in May 2005. The four treatments are: CN (elevated CO2 and high N deposition), CC (elevated CO2 and ambient N deposition), NN (high N deposition and ambient CO2) and CK (ambient CO2 and ambient N deposition). The elevated CO2 was (700 ± 20) μmol·mol–1, and the total amount of added NH4NO3-N was 100 kg N·hm–2·a–1. Leaves were harvested in January 2009, and elements in the leaves were measured.
Important findings Compared to the control, elevated CO2 concentration significantly increased leaf-element contents in all species (p < 0.05) except for Ca content in Ormosia pinnata. High N deposition decreased K and Ca contents in the species. There was no interactive effect of high CO2 concentration and N deposition treatments on most leaf element contents. The interactive effect of high CO2 concentration and N deposition treatments only decreased leaf Ca contents in Schima superba and Syzygium hancei and leaf Mn contents in Schima superba, Syzygium hancei and Ormosia pinnata, as well as increased leaf P content in trees of Acmena acuminatissima.