Project description:Global warming substantially changes precipitation patterns in the Tibetan plateau, with projection of increased precipitation in southern and northern Tibet but decreased precipitation in the center. Understanding mechanisms of such changes in greenhouse gas emissions is of vital importance in predicting ecosystem feedbacks to climate changes. Nonetheless, it has been hampered by limited knowledge in soil microbial communities, one of the major drivers of greenhouse gas emission. Here, we report a field experiment simulating drying and wetting conditions in the Tibetan grassland. Our field site is located at the Haibei Alpine Grassland Ecosystem Research Station in the northeast of Tibet Plateau, China, and we employed GeoChip 5.0 180K to analyze microbial responses. 18 samples were collected from 3 plots in Haibei Station, with 6 replicates in each plot
Project description:Global warming substantially changes precipitation patterns in the Tibetan plateau, with projection of increased precipitation in southern and northern Tibet but decreased precipitation in the center. Understanding mechanisms of such changes in greenhouse gas emissions is of vital importance in predicting ecosystem feedbacks to climate changes. Nonetheless, it has been hampered by limited knowledge in soil microbial communities, one of the major drivers of greenhouse gas emission. Here, we report a field experiment simulating drying and wetting conditions in the Tibetan grassland. Our field site is located at the Haibei Alpine Grassland Ecosystem Research Station in the northeast of Tibet Plateau, China, and we employed GeoChip 5.0 180K to analyze microbial responses.
Project description:Samples of oil and production water were collected from five wells of the Qinghai Oilfield, China, and subjected to GeoChip hybridization experiments for microbial functional diversity profiling. Unexpectedly, a remarkable microbial diversity in oil samples, which was higher than that in the corresponding water samples, was observed, thus challenging previously believed assumptions about the microbial diversity in this ecosystem. Hierarchical clustering separated oil and water samples, thereby indicating distinct functional structures in the samples. Genes involved in the degradation of hydrocarbons, organic remediation, stress response, and carbon cycling were significantly abundant in crude oil, which is consistent with their important roles in residing in oil. Association analysis with environmental variables suggested that oil components comprising aromatic hydrocarbons, aliphatic hydrocarbons, and a polar fraction with nitrogen-, sulfur-, and oxygen-containing compounds were mainly influential on the structure of the microbial community. Furthermore, a comparison of microbial communities in oil samples indicated that the structures were depth/temperature-dependent. To our knowledge, this is the first thorough study to profile microbial functional diversity in crude oil samples. From the Qinghai Oilfield located in the Tibetan Plateau, northwest China, oil production mixtures were taken from four oil production wells (No. 813, 516, 48 and 27) and one injection well (No. 517) in the Yue-II block. The floating oil and water phases of the production mixtures were separated overnight by gravitational separation. Subsequently, the microbial community and the characteristics of the water solution (W813, W516, W48, and W27) and floating crude oil (O813, O516, O48, and O27) samples were analyzed. A similar analysis was performed with the injection water solution (W517).
Project description:Land cover change has long been recognized that marked effect the amount of soil organic carbon. However, little is known about microbial-mediated effect processes and mechanism on soil organic carbon. In this study, the soil samples in a degenerated succession from alpine meadow to alpine steppe meadow in Qinghai-Tibetan Plateau degenerated, were analyzed by using GeoChip functional gene arrays.
Project description:The extreme environments of the Tibetan Plateau offer significant challenges to human survival, demanding novel adaptations. While the role of biological and agricultural adaptations in enabling early human colonization of the plateau has been widely discussed, the contribution of pastoralism is less well understood, especially the dairy pastoralism that has historically been central to Tibetan diets. Here, we analyze preserved proteins from the dental calculus of 40 ancient individuals to report the earliest direct evidence of dairy consumption on the Tibetan Plateau. Our palaeoproteomic results demonstrate that dairy pastoralism began on the higher plateau by approximately 3,500 years ago, more than 2,000 years earlier than the recording of dairying in historical sources. With less than 1% of the Tibetan Plateau dedicated to farmland, pastoralism and the milking of ruminants were essential for large-scale human expansion into agriculturally-marginal regions that make up the majority of the plateau. Dairy pastoralism allowed conversion of abundant grasslands into nutritional human food, which facilitating adaptation in the face of extreme climatic and altitudinal pressures, and maximizing the land area available for long-term human occupation of the “roof of the world”.
Project description:Due to its high altitude and extreme climate conditions, the Tibetan plateau is a region vulnerable to the impact of climate changes and anthropogenic perturbation, thus understanding how its microbial communities function may be of high importance. Here, we report a study to profile soil microbial structural genes, which infers functional roles of microbial communities, aiming to explore potential microbial responses to climate changes and anthropogenic perturbation. Using a microarray-based metagenomics tool named GeoChip 4.0, we showed that microbial communities in treatment site were distinct, compared with those in control site, e.g. shrubland vs grassland, grazing site vs ungrazing site, or warmer site vs colder site. Substantial variations were apparent in stress, N and C cycling genes, but they were in line with the functional roles of these genes.
Project description:Higher incidence of chronic atrophic gastritis (CAG) is generally considered a precancerous lesion of gastric cancer (GC). Therefore, the early diagnosis and treatment of CAG, especially in Tibetan Plateau areas, play an important role in the prevention of GC. The atrophic and non-atrophic gastric mucosal tissue samples from 7 patients with chronic gastritis (CG) and cancer tissue samples from 3 patients with GC were collected. High-throughput sequencing was performed to identify the differentially expressed in lncRNAs, circRNAs, miRNAs, and mRNAs, followed by the construction of competitive endogenous RNA (ceRNA) regulatory networks (lncRNA/circRNA-miRNA-mRNA network) in CAG. Those differentially expressed mRNAs with the same expression trend in both CAG and GC were further identified. Two datasets (GSE153224 and GSE163416), involving data in non-Tibetan Plateau areas, were used to further screen out plateau-specific mRNAs in CAG, followed by identification of the plateau-specific and ferroptosis related mRNAs. GO and KEGG enrichment analysis were performed to investigate the biological functions of plateau-specific mRNAs in CAG. This study may provide useful information for identifying potential biomarkers for the diagnosis of CAG.
Project description:Higher incidence of chronic atrophic gastritis (CAG) is generally considered a precancerous lesion of gastric cancer (GC). Therefore, the early diagnosis and treatment of CAG, especially in Tibetan Plateau areas, play an important role in the prevention of GC. The atrophic and non-atrophic gastric mucosal tissue samples from 7 patients with chronic gastritis (CG) and cancer tissue samples from 3 patients with GC were collected. High-throughput sequencing was performed to identify the differentially expressed in lncRNAs, circRNAs, miRNAs, and mRNAs, followed by the construction of competitive endogenous RNA (ceRNA) regulatory networks (lncRNA/circRNA-miRNA-mRNA network) in CAG. Those differentially expressed mRNAs with the same expression trend in both CAG and GC were further identified. Two datasets (GSE153224 and GSE163416), involving data in non-Tibetan Plateau areas, were used to further screen out plateau-specific mRNAs in CAG, followed by identification of the plateau-specific and ferroptosis related mRNAs. GO and KEGG enrichment analysis were performed to investigate the biological functions of plateau-specific mRNAs in CAG. This study may provide useful information for identifying potential biomarkers for the diagnosis of CAG.