摘要
The production of toxic sulfides is a common environmental problem in mariculture.Therefore,the effective inhibition of sulfidogens is the key to prevent sulfides production.In this study,the possibility and mechanism of nitrate(NO_(3)^(−))inhibiting the activity of the sulfate-reducing microbiota(SRM)from mariculture sediments was investigated.The results showed that 1,3,and 5 mmol L^(−1)NO_(3)^(−)continuously inhibited sulfide production for 1-3 d.As NO_(3)^(−) dosage increased to 7 mmol L^(−1),the duration of inhibition increased to 6 days.Denitrifying product NO_(2)^(−)heavily inhibited the activity of dissimilar sulfate reductase gene(dsrB)by 3 orders,which was the main reason that the sulfate-reducing activity was inhibited.The SRM structure changed significantly with the dosage of NO_(3)^(−),while the abundance of sulfidogens Desulfovibrio species increased due to their capability of detoxifying nitrite through nitrite reductase.Hence,sulfidogens Desulfovibrio species are more adaptable to a high nitrate/nitrite environment,and the traditional control strategies by dosing nitrate/nitrite should be paid more attention to.The findings will serve as helpful guidelines for sulfate-reducing microbiota in the habitat of mariculture to reduce their generation of poisonous sulfide.
基金
supported by the National Natural Science Foundation of China(No.41977315)
the Fundamental Research Funds for the Central Universities of China(No.201964004).