title: Effects of enhanced UV-B radiation on the diversity and activity of soil microorganism of alpine meadow ecosystem in Qinghai-Tibet Plateau.
abstract: The effects of enhanced UV-B radiation on abundance, community composition and the total microbial activity of soil bacteria in alpine meadow ecosystem of Qinghai-Tibet Plateau were investigated. Traditional counting and 16S rRNA gene sequencing were used to investigate the culturable bacteria and their composition in soil, meanwhile the total microbial activity was measured by microcalorimetry. The population of soil culturable bacteria was slightly reduced with the enhanced UV-B radiation in both of the two depths, 2.46 × 10(6) CFU/g in upper layer (0-10 cm), 1.44 × 10(6) CFU/g in under layer (10-20 cm), comparing with the control (2.94 × 10(6) CFU/g in upper layer, 1.65 × 10(6) CFU/g in under layer), although the difference was not statistically significant (P > 0.05). However, the bacteria diversity decreased obviously due to enhanced UV-B, the number of species for upper layer was decreased from 20 to 13, and from 16 to 13 for the lower layer. The distribution of species was also quite different between the two layers. Another obvious decrease induced by enhanced UV-B radiation was in the total soil microbial activities, which was represented by the microbial growth rate constant (k) in this study. The results indicated that the culturable bacteria community composition and the total activity of soil microbes have been considerably changed by the enhanced UV-B radiation.
authors.affiliation: State Key Laboratory of Frozen Soil Engineering, Chinese Academy of Sciences, Lanzhou, 730000, China.
authors.forename: Fujun
authors.initials: F
authors.lastname: Niu
authors.forename: Junxia
authors.initials: J
authors.lastname: He
authors.forename: Gaosen
authors.initials: G
authors.lastname: Zhang
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Maoxing
authors.initials: M
authors.lastname: Dong
authors.forename: Fasi
authors.initials: F
authors.lastname: Wu
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Ma
authors.forename: Lizhe
authors.initials: L
authors.lastname: An
authors.forename: Huyuan
authors.initials: H
authors.lastname: Feng
mesh_terms: D044822:Biodiversity; D017753:Ecosystem; D065948:Grassland; D012988:Soil Microbiology; D018609:Tibet; D014466:Ultraviolet Rays