Succession of marine bacteria in response to Ulva prolifera-derived dissolved organic matter
Succession of marine bacteria in response to Ulva prolifera-derived dissolved organic matter
复制标题
海洋细菌对石莼衍生的溶解有机物的反应
DOI：
10.1016/j.envint.2021.106687
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发表时间：
2021-06-15
影响因子：
11.8
通讯作者：
Zhang, Xiao-Hua
中科院分区：
文献类型：
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作者：
Liang, Jinchang;Liu, Jiwen;Zhang, Xiao-Hua
由于气候变暖和沿海富营养化，大型藻类大量繁殖现象日益严重，对海洋环境产生了深远影响。2007年至今，每年夏季中国黄海发生的石莼大爆发，形成了世界上最大的绿色潮。绿色潮向海水中释放大量的溶解有机物（DOM），造成有机物超载。然而，海洋细菌如何应对这一问题以及对海洋环境的潜在影响仍不清楚。在这里，我们监测的高度时间分辨动态的海洋细菌群落发生在响应石莼增殖衍生DOM进行168小时的微宇宙培养实验。DOM输入显着增加细菌丰度在6 h内，降低细菌多样性，并引发明确的社区演替在整个孵化期间。γ-变形菌中的弧菌在短时间内（6-24 h）生长迅速，其相对丰度占活性细菌的52.5%。在24 ~ 48 h，黄杆菌属的部分菌群生长迅速，且在高浓度DOM下生长较低浓度时更为明显。在较晚的时间点（>48 h），α变形菌门的Donghicola属占优势。这种细菌群落演替伴随着12种不同胞外酶活性的显著变化，导致溶解有机碳在前36 h内迅速减少74.5%。总之，我们的研究表明，DOM输入后的细菌群落和胞外酶活性的快速演替，这表明细菌对石莼衍生的有机物的反应可能有助于环境恢复，并可能构成健康威胁，由于潜在的致病性弧菌的水华。
Increasing macroalgal blooms as a consequence of climate warming and coastal eutrophication have profound effects on the marine environment. The outbreaks of Ulva prolifera in the Yellow Sea of China occurring every summer since 2007 to present have formed the world's largest green tide. The green tide releases huge amounts of dissolved organic matter (DOM) to the seawater, causing an organic overload. However, how marine bacteria respond to this issue and the potential impact on the marine environment are still unclear. Here, we monitored the highly temporally resolved dynamics of marine bacterial community that occur in response to Ulva prolifera-derived DOM by performing a 168-h microcosm incubation experiment. DOM inputs significantly increased bacterial abundances within 6 h, decreased bacterial diversity and triggered clear community successions during the whole period of incubation. Vibrio of Gammaproteobacteria robustly and rapidly grew over short timescales (6-24 h), with its relative abundance accounting for up to 52.5% of active bacteria. From 24 to 48 h, some genera of Flavobacteriia grew rapidly, which was more conspicuous at a higher DOM concentration than at a lower concentration. The genus Donghicola of Alphaproteobacteria was predominant at later time points (>48 h). This bacterial community succession was accompanied by significant variations in the activity of 12 different extracellular enzymes, resulting in a rapid reduction of dissolved organic carbon by 74.5% within the first 36 h. In summary, our study demonstrates rapid successions of bacterial community and extracellular enzyme activity after DOM inputs, suggesting that the bacterial response to Ulva prolifera-derived organic matter may contribute to environmental restoration and may pose a health threat due to the bloom of potential pathogenic Vibrio.