Airborone Micobial Characteristics Of West Lake Scenic Area In Hangzhou

Airborne microbes play an important role in urban ecosystems.Air microbial aerosols are close related to air pollution,environmental quality,and people's quality of life and health.This study takes Hangzhou West Lake Scenic area as the research object,and selects Orioles Singing in the Willows(OSW),Precious Stone Hill Floating in Rosy Clouds(PSHFRC),and Lingering Snow on the Broken Bridge(LSBB)and Viewing Fish at Flower Pond(VFFP)as samples.We use Anderson air bioparticles and Coriolis?liquid air bioparticle sampler studied the changes of air microbial concentration and particle size and the characteristics of air microbial community structure with using traditional culturable methods,high-throughput sequencing and bioinformatics analysis.We provide theoretical guidance and reference basis for controlling air biological pollution in the West Lake scenic area and formulate environmental policies and regulations for relevant management departments.The overall air microbial concentration in the air of the West Lake scenic area is609 CFU/m~3,the concentration of airborne bacteria is 107 CFU/m~3,and the concentration of airborne fungi is 502 CFU/m~3,and air fungi accounted for 80.0%of total airborne microorganisms.Among 4 scenic spots,OSW has the highest air microbial concentration of 695 CFU/m~3,and PSHFEC has the lowest air microbial concentration of 572 CFU/m~3.The air microbial concentration of each scenic spot and the proportion of airborne bacteria and airborne fungi in airborne microorganisms were also different.Among 4 scenic spots,OSW has the highest airborne fungi content,accounting for 87.0%,and LSBB has the lowest airborne fungi content,accounting for 73.0%.The air microbial concentration in the West Lake scenic area decreased with the spring,summer,autumn and winter seasons,and reached the lowest in winter.The airborne bacterial concentration in the West Lake scenic area were high in the spring and autumn,with 142 CFU/m~3 and 136 CFU/m~3 respectively,and the lowest in winter,with 56 CFU/m~3.Among 4 scenic spots,LSBB has the highest airborne bacterial concentration of 148 CFU/m~3,and OSW has the lowest airborne bacterial concentration of 97 CFU/m~3.The particle size distribution of airborne bacteria is skewed distribution,with the highest particle size capture rate of>8.2?m,exceeding 30.0%.At the phylum level,the three most populous doors of the four attractions are Proteobacteria,Firmicutes and Bacteroidetes.At the genus level,although the content of the dominant genus in each scenic spot is significantly different,the most common species in each sample is roughly the same:the most abundant genus of PSHFRC is Aeromonas,accounting for the total PSHFRC The proportion of the genus Bacillus is 20.88%,the bacterium with the highest relative content of LSBB is Ralstonia,accounting for 56.41%of the total genus of LSBB.The most common genus of VFFP is Ralstonia,accounting for 20.87%of the total genus of VFFP.OSW is relatively The most abundant genus is Ralstonia,which accounts for 16.04%of the total genus of OSW.The airborne fungal concentration in the West Lake scenic area was the highest in the spring,with 745 CFU/m~3,and the lowest in winter,with 256 CFU/m~3.Among 4scenic spots,OSW had the highest airborne fungal concentration of 619 CFU/m~3,and LSBB had the lowest airborne fungal concentration of 394 CFU/m~3.Among 4 scenic spots,OSW had the highest airborne fungal concentration of 619 CFU/m~3,and LSBB had the lowest airborne fungal concentration of 394 CFU/m~3.The particle size distribution of airborne fungi showed a normal distribution,and the particle size capture rate of 3.0?6.0?m,2.0?3.5?m and 1.0?2.0?m accounted for nearly 80.0%of the total air fungi.The airborne fungi have significant differences in the dominant genus content of the scenic spots at the genus level,but the most common genus type of each sample is roughly the same:the most abundant genus of PSHFRC is Penicillium,accounting for the total number of genus PSHFRC.18.75%,the most abundant LSBB is Cladosporium,which accounts for 22.08%of the total genus of LSBB.The most common genus of VFFP is Rhizopus,accounting for 39.98%of the total number of VFFP genus,and the highest content of OSW.The genus Penicillium accounts for 37.17%of the total number of OSW bacteria.The ?-diversity analysis of airborne bacteria showed that the airborne microbial abundance of PSHFRC was relatively low but the uniformity was high.The?-diversity index of different seasons was compared.It was found that the air microbial abundance in spring was lower but the uniformity was higher.The content of a single microflora is low,and the relative abundance of air in the autumn is higher and the degree of uniformity is lower.The?-analysis of airborne bacteria resulted in similar OSW and VFFP in autumn,and LSBB and the other three samples had the lowest similarity.This may be due to the similarity of PSHFRC and VFFP air microbial flora;while OSW differs greatly from other samples in air microbial abundance and diversity.Through PCA analysis,it was found that the PCA of OSW and LSBB was different,and the difference between PSHFRC and VFFP was small.