Search

How the soil bacterial communities vary with elevation is context-dependent, and the effect of soil translocation between elevations on bacterial community structure and metabolic function was not fully understood yet. Here, the bacterial community composition and diversity at five elevations along a 1600–3000 m elevation gradient on a mountainside in northwest Sichuan were characterized, and the responses of soil bacterial community to simulated climate changes were further studied by soil translocation reciprocally at three elevations for 12 months. Significant differences were found in soil temperature and moisture at different elevations, but there was no observed change in bacterial alpha diversity. The relative abundance of bacterial phyla was significantly different among the five elevations except for Proteobacteria (the dominant bacterial phyla in five elevation), and most bacterial phyla correlated with soil temperature, moisture, pH and soil bulk density. The direct effect of soil properties (pH, soil nutrients and soil bulk density) on soil bacterial community was stronger than the direct effect of temperature and moisture. Soil translocation changed the relative abundance of some bacterial phyla, and taxonomic groups with significant changes were mainly non-dominant phyla rather than the dominant phyla. Metabolism was the primary function of bacterial community at all elevations, which accounted for ~ 80% of relative abundance, and soil translocation had little effect on metabolic function. These findings indicated that soil bacterial dominant taxa and soil bacterial metabolic functions are relatively stable, which contribute to the stability of the ecosystem when response to the climate change in the future. [ABSTRACT FROM AUTHOR]

Copyright of Parasite (1252607X) is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dicrocoelium chinensis is commonly known as the 'lancet fluke' or 'small liver fluke' which lives in the bile ducts and gall bladder of domestic and wild ruminants. In this study, we examined sequence variability in two mitochondrial (mt) genes, namely cytochrome c oxidase subunit 1 ( cox1) and NADH dehydrogenase subunit 1 ( nad1) genes, among D. chinensis isolated from domestic yaks in Gansu and Sichuan provinces, China. A portion of the cox1 (p cox1) and nad1 (p nad1) genes was amplified by PCR separately from the individual adult D. chinensis, and the amplicons were subjected to sequencing from both directions. The lengths of the sequences of p cox1 and p nad1 were 358 and 458 bp, respectively. The A+T contents of the sequences were 58.94-59.22% for p cox1 and 60.04-60.48% for p nad1, respectively. The intra-specific sequence variations within D. chinensis were 0-0.84% for p cox1 and 0-0.87% for p nad1. The inter-specific sequence differences among members of the examined trematodes were significantly higher, being 22.9-29.3% and 33.6-41.5% for p cox1 and p nad1, respectively. Phylogenetic analysis utilizing combined sequences of p cox1 and p nad1 using Bayesian inference revealed that all of the D. chinensis isolates grouped together with high statistical support. These findings demonstrated the existence of low intra-specific variation in mitochondrial DNA (mtDNA) sequences among the D. chinensis isolates from domestic yaks in China and had implications for studying the molecular epidemiology and population genetics of D. chinensis. [ABSTRACT FROM AUTHOR]