Abstract:
Wesupplemented different concentrations of Cu2+, Mg2+, Zn2+, Fe3+, Mn2+ to the substrate to study their influence on the growth and nitrite removal of Rhodopseudomonas palustris strain 2-8. It is found that 110-7 molL-1 Cu2+ improves but 110-4 molL-1 Cu2+ inhibits the growth and nitrite removal of strain 2-8;110-6 and 110-5 molL-1 Cu2+ inhibits the growth but improves the nitrite removal. 110-4 molL-1 Mg2+ improves the growth and nitrite removal. Zn2+ has no significant influence on the growth but low concentration (110-6 molL-1 and 110-7 molL-1) of Zn2+ improves the nitrite removal, while high concentration (110-6 molL-1) is the opposite. The higher the concentration of Fe3+ is, the better the growth is but the worse the nitrite removal is. Mn2+ inhibits the growth and 110-6~110-3 molL-1 Mn2+ inhibits the nitirte removal. Except 110-4 molL-1 Cu2+ which inhibits nitrite removal greatly, the inhibition of the other metal ions becomes weaker with time.