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Long-term observations have shown that many plants and aboveground animals have changed their phenology patterns due to warmer temperatures over the past decades. However, empirical evidence for phenological shifts in alpine organisms, particularly belowground organisms, is scarce. Here, we investigate how the activities and phenology of plants, soil microbes, and soil fauna will respond to warming in an alpine meadow on the Tibetan Plateau, and whether their potential phenological changes will be synchronized. We experimentally simulate an increase in soil temperature by 2–4 °C according to future projections for this region. We find that warming promotes plant growth, soil microbial respiration, and soil fauna feeding by 8%, 57%, and 20%, respectively, but causes dissimilar changes in their phenology during the growing season. Specifically, warming advances soil faunal feeding activity in spring and delays it in autumn, while their peak activity does not change; whereas warming increases the peak activity of plant growth and soil microbial respiration but with only minor shifts in their phenology. Such phenological asynchrony in alpine organisms may alter ecosystem functioning and stability. Phenological shifts driven by climate change are well-studied in plants and aboveground animals, but scarcely in belowground biota. Here, the authors show that soil warming causes phenological mismatches between plants, soil microbes and soil microarthropods in an alpine meadow. [ABSTRACT FROM AUTHOR]

Aims: The ecological roles of dinitrogen-fixing plants (N2-fixers) in the early stage of primary succession remain unclear. We aimed to examine the effects of pioneer N2-fixers on the resource status and establishment of neighboring non-N2-fixing plants (non-fixers) in a newly formed glacier floodplain, eastern Tibetan Plateau. Methods: We set up three plots in the floodplain and assessed the abundance, height, and coverage of two N2-fixing and three non-fixing species. We also collected plant and soil samples for the analyses of nutrient status and stable isotope signatures. Results: The two N2-fixing species acquired > 80% of the nitrogen (N) from N2 fixation. The cushion-forming N2-fixer Astragalus mahoshanicus increased the soil nutrient availability compared with the non-fixers and improved the microclimate beneath the cushions. Natural 15N abundance indicated significant transfer of N from A. mahoshanicus to its neighboring non-fixers. Consequently, the neighboring non-fixers were significantly higher in N concentration, above-ground to below-ground biomass ratio and height and density than the non-fixers growing alone, but more deficient in some rock-derived nutrients. The other N2-fixer Hippophae rhamnoides (in seedling stage) generally did not increase the resource availability, and its neighboring non-fixers were similar in height and lower in density than the non-fixers growing alone. Conclusions: The effects of pioneer N2-fixers on the resource status and establishment of neighboring non-fixers in the subalpine floodplain were species dependent and were related to the life history traits of the N2-fixers. A. mahoshanicus has the potential to be used in the restoration of newly exposed land in subalpine regions. [ABSTRACT FROM AUTHOR]

Background: An earthquake struck Yushu in Qinghai province of China on April 14, 2010, causing 2698 deaths and 12,135 injuries.The present study aimed to assess the health status, and associated determinants, of child survivors in the epicenter of the Yushu earthquake 6 years after the event.Methods: A cross-sectional survey was performed among students from two junior schools in Yushu County. Descriptive statistics, t-tests, ANOVA, Wilcoxon rank sum tests, Kruskal-Wallis H tests and stepwise linear regression analysis were used for data analysis.Results: The mean scores onmental component summary (MCS)and physical component summary (PCS) were 42.13 (SD 7.32) and 42.04 (SD 8.07), respectively. Lower PCS in the aftermath of an earthquake was associated with being trapped/in danger, injured to self, receiving no escape training while lowerMCS in the aftermath of an earthquake was associated with a lower grade level, not living with parents, fear during the earthquake, death in the family, and not receiving psychological counseling after the earthquake.Conclusions: In conclusion, the results of the present study help to expand our knowledge regarding the health status of child survivors 6 years after the Yushu earthquake. Our study provides evidence-based suggestions for specific long-term health interventions in such vulnerable populations. [ABSTRACT FROM AUTHOR]

The availability of phosphorus (P) in soils will ultimately determine forest productivity because of increasing P limitation in terrestrial ecosystems. However, it is still unclear how and to what extent of different plant P-acquisition strategies affect soil P cycling in the subalpine ecosystems. Here, bulk soils (BS) and rhizosphere soils (RS) under Abies fabri and Rhododendron decorum were respectively collected in the early-, mid- and late-growing seasons in a subalpine forest of eastern Tibetan Plateau, and low molecular weight organic acids, microbial biomass P and P fractions were analyzed to decipher the effects of the plants on soil P availability. The P fractions in both BS and RS showed a distinct difference between A. fabri and R. decorum because of their different P acquisition strategies. The ericoid mycorrhiza-associated R. decorum sequestered soil available P through organic P mineralization, while the ectomycorrhizal mycorrhiza-associated A. fabri directly or indirectly acquired both the organic and inorganic P pools. Seasonal variations in soil available P further revealed that the difference in the P acquisition by the two species was closely associated with their growing stages. Inorganic P dissolution by citric acid determined available P supply for A. fabri in the mid-growing season, while organic P mineralization contributed to available P for R. decorum in the early-growing season. Our results indicate that mycorrhizal types and plant growing stages drive plant P acquisition, which results in the coexistence patterns of different species in the same habitat. • Different P acquisition strategies between A. fabri and R. decorum regulated soil P transformation. • R. decorum acquired soil P through organic P mineralization. • A. fabri acquired soil P through direct uptake of bioavailable organic and inorganic P. • Distinct growing stages of the two plants caused seasonal difference in soil bioavailable P. [ABSTRACT FROM AUTHOR]

Biomonitoring permits determinations of trace metal contamination in remote areas like the high mountain ecosystems. In this study, six trace metals (Cd, Cr, Cu, Ni, Pb, and Zn) in seven sympatric alpine species (five tree species: Salix rehderiana , Populus purdomii , Betula albosinensis , Abies fabri , Picea brachytyla , and two dominant mosses: Pleurozium schreberi , Papillaria crocea ) at the Hailuogou Glacier foreland, Eastern Tibetan Plateau, were investigated to monitor their contamination. The concentrations of trace metals and Pb isotopic ratios ( 206 Pb/ 207 Pb and 208 Pb/ 206 Pb) in leaves/needles, twigs, bark, roots, and mosses were determined, and the biological factors and enrichment factors were calculated. The concentrations of Cd, Cr, Pb, and Zn in mosses were significantly higher than those in tree tissues and normal plants indicating the exogenous sources. The accumulation of trace metals (except Cd and Zn) was relatively higher in the tree roots, whereas their enrichments were significant in the leaves/needles and bark. According to biological factors, enrichment factors, and factor analysis, Cd, Pb, and Zn in trees and mosses were markedly impacted by anthropogenic emissions, whereas Cr, Cu, and Ni in trees were mainly from root adsorption from soils. The Pb isotopic compositions identified the anthropogenic Pb mainly from mining and smelting, coal combustion, and vehicle exhausts. The results indicated that mosses were still priority indicator of trace metal contamination from atmospheric deposition, and the leaves and bark of S. rehderiana , P. purdomii , and B. albosinensis were the better alternatives to monitor the atmospheric contamination of trace metals in the alpine ecosystem. [ABSTRACT FROM AUTHOR]