State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; Graduate University of Chinese Academy of Sciences, China.
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
Water Res. 2016 Jun 1;96:94-104. doi: 10.1016/j.watres.2016.03.030. Epub 2016 Mar 21.
Increasing sulfate input has been seen as an issue in management of aquatic ecosystems, but its influences on eutrophic freshwater lakes is not clear. In this study, it was observed that increasing sulfate concentration without additional cyanobacterial bloom biomass (CBB) addition did not have an obvious effect on element cycling during 1-year continuous flow mesocosm experiments in which water and sediments were taken from a shallow eutrophic lake with sulfate levels near 1 mM. However, following addition of CBB to mesocosms, sulfate-reducing bacteria (SRB) were observed in the water column, and increasing numbers of SRB in the water column were associated with higher sulfate input. Sulfate amendment (0-70 mg L(-1)) also resulted in a larger amount of total dissolved sulfide (peak values of 5.90 ± 0.36 to 7.60 ± 0.12 mg L(-1)) in the water column and acid volatile sulfide (1081.71 ± 69.91 to 1557.98 ± 41.72 mg kg(-1)) in 0-1 cm surface sediments due to sulfate reduction. During the period of CBB decomposition, increasing sulfate levels in the water column were positively correlated with increasing diffusive phosphate fluxes of 1.23 ± 0.32 to 2.17 ± 0.01 mg m(-2) d(-1) at the water-sediment interface. As increases in sulfide and phosphate release rates deteriorated the water quality/ecosystem and even spurred the occurrence of a black water problem in lakes, the control of sulfate input level should be considered for shallow eutrophic lake management, especially during cyanobacterial bloom periods.
增加硫酸盐输入一直被认为是水生生态系统管理中的一个问题，但它对富营养化淡水湖泊的影响尚不清楚。在这项研究中，观察到在从硫酸盐水平接近 1mM 的浅水富营养湖中采集的水和沉积物的为期 1 年的连续流动中观实验中，增加硫酸盐浓度而不增加额外的蓝藻水华生物量（CBB），对元素循环没有明显影响。然而，在向中观系统添加 CBB 后，在水柱中观察到硫酸盐还原菌（SRB），水柱中 SRB 的数量增加与硫酸盐输入增加有关。硫酸盐添加（0-70mgL(-1)）也导致水柱中总溶解硫化物（峰值为 5.90±0.36 至 7.60±0.12mgL(-1)）和 0-1cm 表面沉积物中酸可挥发性硫化物（1081.71±69.91 至 1557.98±41.72mgkg(-1)）的含量增加，这是由于硫酸盐还原。在 CBB 分解期间，水柱中硫酸盐水平的增加与水-沉积物界面上扩散性磷酸盐通量的增加呈正相关，从 1.23±0.32 增加到 2.17±0.01mgm(-2)d(-1)。随着硫化物和磷酸盐释放速率的增加，水质/生态系统恶化，甚至引发湖泊黑水问题，因此在管理浅水富营养湖泊时，特别是在蓝藻水华期间，应考虑控制硫酸盐输入水平。
