Journal of Tropical Oceanography ›› 2017, Vol. 36 ›› Issue (2): 12-18.doi: 10.11978/2016069CSTR: 32234.14.2016069

• Orginal Article • Previous Articles     Next Articles

Effect of aluminum on the growth and nitrogen fixation of a marine nitrogen-fixing cyanobacterium: Crocosphaera watsonii

Jiaxing LIU1,2,3(), Linbin ZHOU1,2, Zhixin KE1,2, Gang LI1,2, Rongjun SHI1,2,3, Yehui TAN1,2()   

  1. 1. Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
    2. Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
    3. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2016-07-25 Revised:2016-08-31 Online:2017-03-20 Published:2017-04-06
  • Supported by:
    National Program on Key Basic Research Project (“973” Program)(2015CB4529000, 2015CB452903);National Science Foundation of China (41276162, 41506150);Strategic Priority Research Program of the Chinese Academy of Sciences (XDA11020200);Special Fund for Agro-scientific Research in the Public Interest (201403008);Science and Technology Planning Project of Guangdong Province (2014B030301064)

Abstract:

Although a large amount of aluminum enters the ocean through atmospheric dust deposition every year, the effect of aluminum on marine phytoplankton is seldom examined. Few studies focused on the effects of aluminum on marine nitrogen-fixing cyanobacteria, which play important roles in nitrogen and carbon cycling in the ocean. In this study, a unicellular marine nitrogen-fixing cyanobacterium Crocosphaera watsonii grew in Aquil medium without silicate and nitrogen by semi-continuous cultures. We studied the effect of aluminum (0, 0.2, 2 and 20 μmol•L-1) on the growth rate and nitrogen fixation rate of Crocosphaera watsonii by using flow cytometry and 15N isotope tracer method. Results showed that aluminum inhibited the growth and nitrogen fixation of Crocosphaera watsonii. Results also showed that cell size, cellular pigments and photochemical efficiency of photosystem II (Fv/Fm) of Crocosphaera watsonii treated with aluminum were significantly decreased. These results demonstrate that aluminum has an inhibitory effect on the growth and nitrogen fixation of Crocosphaera watsonii under the condition of sufficient phosphate and trace nutrients.

Key words: aluminum, nitrogen-fixing cyanobacteria, Crocosphaera watsonii, growth rate, nitrogen fixation

CLC Number: 

  • P735