Abstract:

To investigate the effect of waterlogging on soil nutrients and microbial community structure in a tea plantation (Camellia sinensis L.), a field experiment was conducted using soil submerged by natural rainfall. This study focused on red soils subjected to different flooding durations (15, 17, 19, and 21 d) after heavy rainfall and analyzed the impacts of waterlogging on soil pH, organic matter, alkali-hydrolyzable nitrogen, available potassium, and available phosphorus content, as well as changes in soil microbial community structure and diversity. The results showed that flooding increased soil pH but decreased the content of organic matter, alkali-hydrolyzable nitrogen, available potassium, and available phosphorus in the soil. Regarding microbial community structure, the dominant bacterial phyla in waterlogged tea garden soil were Proteobacteria, Acidobacteriota, and Chloroflexi, while the dominant fungal phyla were Ascomycota and Basidiomycota. At the phylum level, the relative abundances of anaerobic Bacteroidetes and Gemmatimonadetes significantly increased with prolonged flooding (p<0.05). Flooding also increased the relative abundance of Proteobacteria but decreased that of Acidobacterita and Chloroflexi. At the genus level, flooding significantly increased the relative abundance of the beneficial Penicillium, which was positively correlated with soil pH, and the potential nitrogen-fixing genus Candidatus_Solibacter, which exhibited a significant negative correlation with soil pH. This study demonstrated that flooding tea garden soils significantly elevated soil pH and enhanced the abundance of beneficial anaerobic bacteria, while reducing soil nutrient content. These findings provide important guidance for water management in tea plantations following heavy rainfall.

Key words: tea garden soil, flooding, nutrient content, microbial community structure

摘要：

为探究淹水对茶树（Camellia sinensis L.）茶园红壤土壤养分及微生物群落结构的影响，以经自然降雨淹没的茶园土壤为材料，采用田间试验，以暴雨后不同淹水时间（15、17、19、21 d）的茶园红壤为研究对象，分析淹水对土壤pH值、有机质、碱解性氮、速效钾和有效磷含量的影响，并探究淹水后土壤微生物群落结构和多样性的变化。结果表明，淹水导致茶园土壤pH值升高，而有机质、碱解性氮、速效钾和有效磷的含量降低。茶园土壤淹水后，优势细菌门是变形菌门（Proteobacteria）、酸杆菌门（Acidobacterita）和绿弯菌门（Chloroflexi），优势真菌门是子囊菌门（Ascomycota）、担子菌门（Basidiomycota）。此外，在门水平上，厌氧菌拟杆菌门（Bacteroides）和芽单胞菌门（Gemmatimonadetes）的相对丰度随着淹水时间的延长而增加（p<0.05）。茶园土壤淹水后导致变形菌门（Proteobacteria）的相对丰度增加，而酸杆菌门（Acidobacterita）和绿弯菌门（Chloroflexi）的相对丰度降低。在属水平上，茶园土壤淹水显著增加了有益菌属青霉属（Penicillium）的相对丰度并与土壤pH值呈显著正相关，增加了潜在固氮菌类群中的假丝酵母菌属（Candidatus_Solibacter）的相对丰度并与土壤pH值呈显著负相关。茶园土壤淹水显著提高了土壤pH值，增加了土壤中有益厌氧菌的丰度，但土壤养分含量降低，研究结果对未来突发暴雨天气后茶园的水分管理具有指导意义。

关键词: 茶园土壤, 淹水, 养分含量, 微生物群落结构