State Key Laboratory of Water Resources Engineering and Management, Wuhan University, Wuhan, Hubei, 430072, P.R. China.
State Key Laboratory of Water Resources Engineering and Management, Wuhan University, Wuhan, Hubei, 430072, P.R. China; Hubei Key Laboratory of Water System Science for Sponge City Construction(Wuhan University), Wuhan, 430072, China.
J Environ Manage. 2023 Sep 1;341:118026. doi: 10.1016/j.jenvman.2023.118026. Epub 2023 May 14.
With the intensification of human disturbance in urban lakes, the loss of eukaryotic biodiversity (macroinvertebrates, etc.) reduces the accuracy of the index of biotic integrity (IBI) assessment. Therefore, how to accurately evaluate the ecological status of urban lakes based on IBI has become an important issue. In this study, 17 sampling sites from four lakes in Wuhan City, China were selected to analyze the composition and diversity characteristics of benthic and microbial communities and their relationship with environmental factors based on eDNA high-throughput sequencing, and compare the application effects of the benthic index of biotic integrity (B-IBI) and the microbial index of biotic integrity (M-IBI). Canonical correspondence analysis showed that the key environmental factors affecting benthic family/genus composition were temperature, conductivity, total phosphorus (TP), and total nitrogen (TN). Redundancy analysis showed that pH, TP, conductivity, and ammonia nitrogen had the greatest impact on microbial phyla/genera. After screening, four and six core metrics were determined from candidate parameters to establish B-IBI and M-IBI. The B-IBI evaluation results showed that healthy, sub-heathy, and poor accounted for 58.8%, 35.3%, and 5.9%, respectively, in the sites. The results of the M-IBI evaluation showed that 29.4% of the sites were healthy, 47.1% were sub-healthy, and 23.5% were common. M-IBI was positively correlated with water quality (r = 0.74, P < 0.001), whereas B-IBI was not. Further results showed that M-IBI was negatively correlated with the relative abundance of bloom-forming cyanobacteria Planktothrix (r = -0.54, P < 0.05). Therefore, M-IBI is more sensitive than B-IBI and can better reflect the actual water pollution status. This study can provide a new perspective for ecological assessment and management of urban lakes strongly disturbed by human activities.
随着人类对城市湖泊干扰的加剧，真核生物多样性（如大型无脊椎动物等）的丧失降低了生物完整性指数（IBI）评估的准确性。因此，如何基于 IBI 准确评估城市湖泊的生态状况已成为一个重要问题。本研究通过高通量测序的方法，对中国武汉市四个湖泊的 17 个采样点的底栖和微生物群落组成和多样性特征及其与环境因子的关系进行了分析，并比较了底栖生物完整性指数（B-IBI）和微生物生物完整性指数（M-IBI）的应用效果。典范对应分析表明，影响底栖科/属组成的关键环境因素是温度、电导率、总磷（TP）和总氮（TN）。冗余分析表明，pH 值、TP、电导率和氨氮对微生物门/属的影响最大。经过筛选，从候选参数中确定了四个和六个核心指标来建立 B-IBI 和 M-IBI。B-IBI 的评价结果表明，健康、亚健康和较差的站点分别占 58.8%、35.3%和 5.9%。M-IBI 的评价结果表明，健康的站点占 29.4%，亚健康的站点占 47.1%，普通的站点占 23.5%。M-IBI 与水质呈正相关（r=0.74，P<0.001），而 B-IBI 则不然。进一步的结果表明，M-IBI 与形成水华的蓝藻 Planktothrix 的相对丰度呈负相关（r=-0.54，P<0.05）。因此，M-IBI 比 B-IBI 更敏感，能更好地反映实际的水污染状况。本研究可为受人类活动强烈干扰的城市湖泊的生态评估和管理提供新的视角。
