School of Marine Biology and Fisheries, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, PR China; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, PR China.
School of Marine Biology and Fisheries, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, PR China; Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, PR China.
J Environ Manage. 2024 Jan 15;350:119594. doi: 10.1016/j.jenvman.2023.119594. Epub 2023 Nov 22.
Microorganisms play a critical role in maintaining the delicate balance of ecosystem services. However, the assembly processes that shape microbial communities are vulnerable to a range of environmental stressors, such as climate change, eutrophication, and the use of herbicides. Despite the importance of these stressors, little is known about their cumulative impacts on microbial community assembly in aquatic ecosystems. To address this knowledge gap, we established 48 mesocosm experiments that simulated shallow lake ecosystems and subjected them to warming (including continuous warming (W) and heat waves (H)), glyphosate-based herbicides (G), and nutrient loading (E). Our study revealed that in the control group, both deterministic and stochastic processes codominated the assembly of microbial communities in water, whereas in sediment, the processes were primarily stochastic. Interestingly, the effects of multiple stress factors on assembly in these two habitats were completely opposite. Specifically, stressors promoted the dominance of stochastic processes in water but increased the importance of deterministic processes in sediment. Furthermore, warming amplified the effects of herbicides but exerted an opposite and stronger influence on assembly compared to nutrients, emphasizing the complexity of these mechanisms and the significance of considering multiple stressors. The interaction of some factors significantly affected assembly (p < 0.05), with the effects of WEG being most pronounced in water. Both water and sediment exhibited homogeneous assembly of microbial communities (mean NTI >0), but the phylogenetic clustering of microbial communities in water was more closely related (NTI >2). Our research revealed the response model of microbial community assembly in aquatic ecosystems to multiple environmental stresses, such as agricultural pollution, climate change, and eutrophication, and indicated that microbial community changes in sediment may be an important predictor of lake ecosystem development. This provides scientific evidence that better environmental management can reduce impacts on aquatic ecosystems under the threat of future warming.
微生物在维持生态系统服务的微妙平衡中起着至关重要的作用。然而，塑造微生物群落的组装过程容易受到一系列环境胁迫的影响，如气候变化、富营养化和除草剂的使用。尽管这些胁迫因素很重要，但对于它们在水生生态系统中对微生物群落组装的累积影响知之甚少。为了填补这一知识空白，我们建立了 48 个中观实验，模拟了浅水湖泊生态系统，并对其进行了加温（包括持续加温（W）和热浪（H））、草甘膦类除草剂（G）和营养负荷（E）处理。我们的研究表明，在对照组中，确定性和随机性过程共同主导了微生物群落在水中的组装，而在沉积物中，过程主要是随机的。有趣的是，多个胁迫因素对这两种生境中组装的影响完全相反。具体来说，胁迫因素促进了随机性过程在水中的主导地位，但增加了确定性过程在沉积物中的重要性。此外，变暖放大了除草剂的影响，但与营养物质相比，对组装的影响相反且更强，这强调了这些机制的复杂性和考虑多个胁迫因素的重要性。一些因素的相互作用显著影响了组装（p<0.05），其中 WEG 的影响在水中最为明显。水和沉积物都表现出微生物群落的均匀组装（平均 NTI>0），但水中微生物群落的系统发育聚类更为密切（NTI>2）。我们的研究揭示了水生生态系统中微生物群落对多种环境胁迫的组装响应模式，如农业污染、气候变化和富营养化，并表明沉积物中微生物群落的变化可能是湖泊生态系统发展的一个重要预测指标。这为更好的环境管理提供了科学依据，可以减少未来变暖威胁下对水生生态系统的影响。
