Effects of pH on the growth and NH4-N uptake of Skeletonema costatum and Nitzschia closterium

Xingyan Gu; Keqiang Li; Kai Pang; Yunpeng Ma; Xiulin Wang

doi:10.1016/j.marpolbul.2017.01.048

Effects of pH on the growth and NH₄-N uptake of Skeletonema costatum and Nitzschia closterium

Mar Pollut Bull. 2017 Nov 30;124(2):946-952. doi: 10.1016/j.marpolbul.2017.01.048. Epub 2017 Feb 2.

Authors

Xingyan Gu¹, Keqiang Li², Kai Pang¹, Yunpeng Ma¹, Xiulin Wang¹

Affiliations

¹ Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
² Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China. Electronic address: likeqiang@ouc.edu.cn.

PMID: 28162247
DOI: 10.1016/j.marpolbul.2017.01.048

Abstract

Ocean acidification (OA) and eutrophication intensifies in coastal sea under anthropogenic impact. OA coupled with the NH₄-N source effect in coastal water is likely to affect the planktonic ecosystem. In this work, Skeletonema costatum and Nitzschia closterium were chosen as typical species of diatom in Chinese coastal ecosystems to test the potential effect of OA and NH₄-N. Results showed that the growth and NH₄-N uptake of S. costatum and N. closterium were significantly inhibited by pH decline. The maximum uptake rate is higher than the maximum growth rate, implying that NH₄-N was assimilated faster for S. costatum and N. closterium with decreasing pH. Therefore, the inhibition rate of the growth of the two diatoms by the coupling effect of OA and eutrophication (pH7.45) is higher that than in the coastal sea by the end of the 21st century (pH7.71).

Keywords: Ammonium nitrogen; Eutrophication; Ocean acidification; Uptake kinetics.

MeSH terms

Ammonium Compounds / metabolism*
China
Diatoms / growth & development*
Diatoms / metabolism*
Eutrophication*
Hydrogen-Ion Concentration
Nitrogen / metabolism*
Seawater / chemistry*

Substances

Ammonium Compounds
Nitrogen