%0 Journal Article %T 富营养化湖泊中硫酸盐对蓝藻衰亡产甲烷过程的影响 %T Effects of sulfates on methane production during cyanobacteria decay processes in eutrophic lakes %A 周川乔,彭宇,邓杨,吕成旭,朋毛羊藏,张思远,许晓光,王瑜,张利民,王国祥 %A Zhou Chuanqiao %A Peng Yu %A Deng Yang %A Lv Chengxu %A Peng Maoyangzang %A Zhang Siyuan %A Xu Xiaoguang %A Wang Yu %A Zhang Limin %A Wang Guoxiang %J 湖泊科学 %J Journal of Lake Sciences %@ 1003-5427 %V 33 %N 6 %D 2021 %P 1639-1649 %K 富营养化湖泊;蓝藻;甲烷;硫酸盐;还原性硫化物;太湖 %K Eutrophic lakes;cyanobacteria;methane;sulfate;reducing sulfides;Lake Taihu %X 随着外源性硫酸盐(SO42-)的持续性输入,富营养化湖泊水体的SO42-浓度持续升高.野外长期监测结果表明,近几十年太湖水体的SO42-浓度逐渐升高,达到了96 mg/L的水平.此外,富营养化湖泊中蓝藻水华衰亡会产生并释放大量的甲烷(CH4),湖泊水体的SO42-浓度升高是否会对沉积物产CH4过程造成影响仍缺乏相关研究.本实验构建了蓝藻水体沉积物微宇宙系统,通过添加30、60、90、120和150 mg/L五组浓度的硫酸盐,探究不同SO42-浓度下蓝藻衰亡过程中水体的SO42-、还原性硫化物(∑S2-)和CH4的变化规律.结果表明,蓝藻聚积衰亡的第6~9天硫酸盐还原作用最为强烈,此时水体中的SO42-浓度快速下降到最低值,依次为7.65、8.87、21.21、41.14和56.54 mg/L.伴随着硫酸盐还原过程的进行,水柱中∑S2-的浓度不断上升,并达到最高值,依次为4.77、6.98、7.49、7.49和7.43 mg/L.蓝藻聚积衰亡的第10~21天水体中的SO42-浓度维持在较低水平,∑S2-浓度逐渐下降,并趋近于0.培养开始时,CH4增长缓慢,SO42-浓度下降之后,CH4浓度逐渐上升,并在第6~9天迅速上升,培养结束时,CH4的最终浓度随着水体初始SO42-浓度的增加而降低,依次为546.39、207.24、79.61、37.25和5.56 μmol/L,CH4的浓度与初始水体SO42-浓度呈指数型负相关关系.因此,对于精准评估富营养化湖泊的产甲烷过程,需要考虑不断上升的SO42-浓度所带来的影响. %X With the continuous input of exogenous sulfate (SO42-), the SO42- concentration in eutrophic lakes continues to increase. Long-term field monitoring results show that the SO42- concentration in Lake Taihu gradually increases to a level of 96 mg/L in recent decades. In addition, the decay of cyanobacteria blooms in eutrophic lakes will increase methane (CH4) production and emission. However, there is still a lack of relevant studies on whether the increase of SO42- concentration in lake water will affect the CH4 production process in sediments. In this study, a cyanobacteria-water-sediment microcosm system was constructed, and five treatments of sulfates (30 mg/L, 60 mg/L, 90 mg/L, 120 mg/L and 150 mg/L) were added to explore the dynamics of SO42-, reducing sulfides (∑S2-) and CH4 in the water during the decay process of cyanobacteria under different SO42- concentrations. The results showed that the sulfate reduction effect was the strongest on the 6th to 9th days when cyanobacteria accumulated and decayed, meanwhile, the SO42- concentration in the water rapidly decreased to the lowest values of 7.65 mg/L, 8.87 mg/L, 21.21 mg/L, 41.14 mg/L and 56.54 mg/L, respectively. Coupled with the process of sulfate reduction, the concentration of ∑S2- in the water column continuously increased to the highest values of 4.77 mg/L, 6.98 mg/L, 7.49 mg/L, 7.49 mg/L and 7.43 mg/L. From the 10th to 21st days of incubation, the concentration of SO42- in the water maintained at a low level, and the concentration of ∑S2- decreased gradually and approached 0. At the initial stage, CH4 slowly increased. After SO42- concentration declined, the CH4 concentration gradually increased, and then rapidly rose from the 6th to 9th days. At the end of incubation, the accumulative CH4 concentration decreased with the increase of initial concentration of SO42- in water, which was 546.39 μmol/L, 207.24 μmol/L, 79.61 μmol/L, 37.25 μmol/L, and 5.56 μmol/L, respectively. There was an exponential negative correlation between CH4 concentration and initial SO42- concentration. Therefore, to accurately assess of methanogenesis process in eutrophic lakes, the influence of rising SO42- concentration should be considered. %R 10.18307/2021.0603 %U http://www.jlakes.org/ch/reader/view_abstract.aspx %1 JIS Version 3.0.0