中国湖泊细菌群落的生物地理分布格局及驱动机制——基于文献数据的统计分析

为阐明中国湖泊细菌群落的生物地理分布格局及驱动机制,基于已发表文献,收集了228个湖泊的浮游或沉积物细菌门水平分类数据和环境因子数据进行分析.结果表明:中国湖泊浮游细菌群落的优势类群为变形菌门(Proteobacteria,35.92%)、放线菌门(Actinobacteria,25.03%)和拟杆菌门(Bacteroidetes,10.77%),沉积物中的优势类群为变形菌门(Proteobacteria,40.37%)、绿弯菌门(Chloroflexi,8.74%)和拟杆菌门(Bacteroidetes,8.55%).中国湖泊浮游细菌距离衰减程度显著低于沉积物细菌;湖泊细菌群落结构在北方、南方、青藏高原的空间差异显著,北方水体及沉积物中细菌的距离衰减模式均不显著,南方水体中显著但沉积物中不显著,青藏高原水体及沉积物中均显著.浮游细菌优势类群中除Proteobacteria外,Actinobacteria (南方>北方>青藏高原)和Bacteroidetes (青藏高原>北方>南方)的丰度在三个地区均具有显著差异;沉积物细菌优势类群Proteobacteria (北方>南方>青藏高原)、Chloroflexi (南方>北方>青藏高原)、Bacteroidetes (青藏高原>北方>南方)的丰度在三个地区均具有显著差异.影响北方湖泊浮游细菌群落分布的主要环境因子是溶解性有机碳,南方是溶解氧,青藏高原是硝酸盐氮;影响北方湖泊沉积物细菌群落分布的主要环境因子是总氮和pH值,南方是总磷,青藏高原是pH值.空间扩散限制与环境筛选作用共同塑造了中国湖泊细菌的生物地理分布格局.扩散限制对浮游细菌的影响小于沉积物细菌,对青藏高原湖泊浮游及沉积物细菌影响最大,对北方湖泊浮游及沉积物细菌影响最小;环境筛选作用对青藏高原湖泊浮游及沉积物细菌影响最大,对南方湖泊浮游细菌及北方湖泊沉积物细菌影响较小.

Biogeographic patterns and assembly mechanisms of bacterial communities in lakes,China-statistical analysis based on the published literature

In order to examine the biogeographic patterns and assembly of bacterial communities in Chinese lakes, data from the published literature on water or sediment bacteria at the phylum level and environmental factors from 228 lakes were collected. Results showed that the dominant taxa of the water bacteria communities in Chinese lakes were Proteobacteria (35.92%), Actinobacteria (25.03%) and Bacteroidetes (10.77%), and the dominant taxa in sediment were Proteobacteria (40.37%), Chloroflexi (8.74%) and Bacteroidetes (8.55%).Distance decay of water bacteria communities was significantly lower than that of sediment bacteria. There was significant spatial difference of lake bacteria communities between Northern China, Southern China and Tibetan Plateau. The distance decay of bacterial communities was not significant in Northern China, but significant in Tibetan Plateau; in Southern China, the distance decay of bacterial communities was significantin lake water, but not significant in lake sediment. The abundance of Actinobacteria (Southern China>Northern China>Tibetan Plateau) and Bacteroidetes (Tibetan Plateau >Northern China>Southern China) in lake waterwere significantly different between the three regions, while Proteobacteria was not. The abundance of Proteobacteria (Northern China>Southern China> Tibetan Plateau), Chloroflexi (Southern China>Northern China> Tibetan Plateau), and Bacteroidetes (Tibetan Plateau >Northern China>Southern China) in lake sediment were significantly different between the three regions. The main environmental factor influencing bacterial communities in lake water of Northern China was dissolved organic carbon, in Southern Chinawas dissolved oxygen, and in Tibetan Plateau was nitrate nitrogen. The main environmental factor influencing bacterial communities in lake sediment of Northern China were total nitrogen and pH, in Southern China was total phosphorus, and in Tibetan Plateauwas pH. Dispersal limitation and variable selection collectively shaped the biogeographic patterns of lake bacteria in China. Dispersal limitation had less impact on water bacteria than sediment bacteria;it had the greatest impact on water and sediment bacteria inTibetan Plateau lakes, and the least impact on water and sediment bacteria in Northern China lakes. Variable selection had the greatest impact on water and sediment bacteria in Tibetan Plateau lakes, andless impact on water bacteria in Southern China lakes and sediment bacteria in Northern China lakes.