Data_Sheet_1_Effects of season and water quality on community structure of planktonic eukaryotes in the Chaohu Lake Basin.DOCX

IntroductionAnalyzing the correlation between planktonic eukaryotic communities (PECs) and aquatic physicochemical parameters (APPs) provides important references for predicting the impact of climate change and human activities on aquatic ecosystems.MethodsTo assess the influence of seasons and APPs on PEC structures in lakes and rivers, we utilized high-throughput sequencing of the 18S rRNA gene to analyze PEC structures in a lake and seven rivers in the Chaohu Lake Basin and analyzed their correlations with APPs.ResultsOur results revealed that PEC structure was significantly affected by season, with the highest α-diversity observed in summer. Furthermore, we identified several APPs, including water temperature, conductivity, dissolved oxygen, pH, phosphate, total phosphorus, trophic level index (TLI), nitrate, ammonia nitrogen, and total nitrogen, that significantly influenced PEC structures. Specifically, we found that Stephanodiscus hantzschii, Simocephalus serrulatus, Cryptomonas sp. CCAC_0109, Pedospumella encystans, Actinochloris sphaerica, Chlamydomonas angulosa, Gonyostomum semen, Skeletonema potamos, Chlamydomonas klinobasis, Pedospumella sp., and Neochlorosarcina negevensis were significantly correlated to TLI, while Limnoithona tetraspina, Theileria sp., and Pseudophyllomitus vesiculosus were significantly correlated to the water quality index (WQI). However, our random forest regression analysis using the top 100 species was unable to accurately predict the WQI and TLI.DiscussionThese results provide valuable data for evaluating the impact of APPs on PEC and for protecting water resource in the Chaohu Lake Basin.

引言：剖析浮游真核生物群落（PECs）与水生物理化学参数（APPs）之间的相关性，为预测气候变化及人类活动对水生生态系统的影响提供了重要参照。方法：为评估季节及APPs对湖泊和河流中PEC结构的影响，本研究采用18S rRNA基因的高通量测序技术，分析了巢湖及其流域内七条河流的PEC结构，并分析了其与APPs之间的相关性。结果：研究结果表明，PEC结构受季节影响显著，夏季的α多样性最高。此外，我们识别出包括水温、电导率、溶解氧、pH值、磷酸盐、总磷、营养水平指数（TLI）、硝酸盐、氨氮和总氮在内的多个APPs对PEC结构产生了显著影响。具体而言，我们发现Stephanodiscus hantzschii、Simocephalus serrulatus、Cryptomonas sp. CCAC_0109、Pedospumella encystans、Actinochloris sphaerica、Chlamydomonas angulosa、Gonyostomum semen、Skeletonema potamos、Chlamydomonas klinobasis、Pedospumella sp.和Neochlorosarcina negevensis与TLI显著相关，而Limnoithona tetraspina、Theileria sp.和Pseudophyllomitus vesiculosus则与水质指数（WQI）显著相关。然而，使用前100种物种进行的随机森林回归分析未能准确预测WQI和TLI。讨论：这些结果为评估APPs对PEC的影响以及保护巢湖流域水资源提供了宝贵数据。