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Global climate models predict that the frequency and intensity of precipitation events will increase in many regions across the world. However, the biosphere‐climate feedback to elevated precipitation (eP) remains elusive. Here, we report a study on one of the longest field experiments assessing the effects of eP, alone or in combination with other climate change drivers such as elevated CO2 (eCO2), warming and nitrogen deposition. Soil total carbon (C) decreased after a decade of eP treatment, while plant root production decreased after 2 years. To explain this asynchrony, we found that the relative abundances of fungal genes associated with chitin and protein degradation increased and were positively correlated with bacteriophage genes, suggesting a potential viral shunt in C degradation. In addition, eP increased the relative abundances of microbial stress tolerance genes, which are essential for coping with environmental stressors. Microbial responses to eP were phylogenetically conserved. The effects of eP on soil total C, root production, and microbes were interactively affected by eCO2. Collectively, we demonstrate that long‐term eP induces soil C loss, owing to changes in microbial community composition, functional traits, root production, and soil moisture. Our study unveils an important, previously unknown biosphere‐climate feedback in Mediterranean‐type water‐limited ecosystems, namely how eP induces soil C loss via microbe‐plant–soil interplay. [ABSTRACT FROM AUTHOR]

Moss-dominated biocrusts are widespread in degraded mining ecosystems and play an important role in soil development and ecosystem primary succession. In this work, the soil microbial community structure under moss-dominated biocrusts in ionic rare earth tailings was investigated to reveal the relationship between different types of moss and taxonomy/function of microbiomes. The results showed that microbial community structure was significantly influenced by four moss species (Claopodium rugulosifolium, Orthotrichum courtoisii, Polytrichum formosum, and Taxiphyllum giraldii). The microbial assembly was more prominent in Claopodium rugulosifolium soil than in the other moss soils, which covers 482 bacterial genera (including 130 specific genera) and 338 fungal genera (including 72 specific genera), and the specific genus is 40% to 1300% higher than that of the other three mosses. Although only 141 and 140 operational taxonomic units (OTUs) rooted in bacterial and fungal clusters, respectively, were shared by all four mosses grown in ionic rare earth tailings, this core microbiome could represent a large fraction (28.2% and 38.7%, respectively) of all sequence reads. The bacterial population and representation are the most abundant, which mainly includes Sphingomonas, Clostridium_sensu_stricto_1, and unclassified filamentous bacteria and chloroplasts, while the fungi population is relatively singular. The results also show that biocrust dominated by moss has a positive effect on soil microbe activity and soil nutrient conditions. Overall, these findings emphasize the importance of developing moss-dominated biocrusts as hotspots of ecosystem functioning and precious microbial genetic resources in degraded rare-earth mining areas and promoting a better understanding of biocrust ecology in humid climates under global change scenarios. [ABSTRACT FROM AUTHOR]

To explore the effect of Portulaca oleracea polysaccharides (POP) in regulating intestinal microflora in aged rats in vitro , its intestinal microbial composition was analyzed by 16 S rDNA high-throughput sequencing, and the level of short-chain fatty acids in fermentation broth was determined by LC-MS. POP significantly upregulated the relative abundance of Lactobacillus , Eggerthella , and Paraprevotella and significantly downregulated Escherichia_Shigella , Bacteroides , and Eubacterium nodatum groups. The pH value and ammonia nitrogen level decreased significantly in the POP-treated group, resulting in a more short-chain fatty acid consumption which changed the acid–base environment of the fermentation broth. In conclusion, POP is beneficial to aged rats because it can regulate intestinal flora, promote the growth of probiotics, and inhibit the reproduction of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

The present study characterized the nutrients availability of three rare earth tailings deserted in different time stages in Southern Jiangxi of China, and revealed the influence of the soil nutrient properties on fungi composition and diversity by using an internal transcribed spacer (ITS) rRNA sequence approach. Three tailings (RS1, RS2 and RS3) and one reference soil (RS4) were sampled. Results showed that a higher levels of AN and TOC occurred in RS1 and RS4, whereas higher contents of SO2-4, TN, NO-3-N, NH+4-N and rare earth elements (REEs) existed in RS2 and RS3, suggesting a high environmental heterogeneity in the different tailings. Metagenomic analysis showed that RS1~RS4 harbored 355, 564, 366 and 507 operational taxonomic units (OTUs), respectively. Alpha diversity analysis showed that RS4, a control sample, had the highest Shannon diversity, whereas RS3, a newly formed tailings, exhibited the lowest Chao1 richness.Among the monitored environmental variables, AN and SO2-4 were the most important factors affecting the overall fungal community composition and the relative abundances of specific lineages. Additionally, genus Penicillium prevailed in RS1and RS4 while genus Aspergillus dominated in RS2 and RS3, indicating that the nitrification maybe conduct by different fungal genus in different tailings. Together, these results suggest that lower fungal community composition and diversity as well as the alteration in fungi-dominated heterotrophic nitrification may be due to the deteriorative nutrient in rare earth tailings, especially increasing level of sulfate and decreasing level of available nitrogen. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two terrace-typed constructed wetlands were designed. [•] Bamboo charcoal (a local biomass resource) was used as a filter media. [•] The structure and diversity of the microbial community were evaluated by PCR-RFLP of the 16S rDNA genes, and Proteobacteria was the most abundant group. [•] The bamboo charcoal and wetland levels may be the main factors affecting the composition of the microbial community. [ABSTRACT FROM AUTHOR]

Comparatively limited knowledge is known about the accumulation processes of tributyltin (TBT) and triphenyltin (TPT) in fish and aquatic plant in the freshwater environment, which has hindered a full understanding of their bioaccumulation potential and ecological risks. In the present study, sorption of TBT and TPT on dead biota of both carp and C. demersum from water via the batch equilibrium technique as well as uptake of them on live biota of both carp and C. demersum from water at a static and a dynamic kinetics tests were investigated, respectively. Both TBT and TPT exhibit a high affinity in carps and C. demersum. And C. demersum has a faster metabolism either for TBT or TPT than carp. The apparent uptake values (C bio = 1904–8831 μg/kg) or bioconcentration factor (BCF = 3333–44000 L/kg) were one or two orders of magnitude higher than that of estimated by a simple sorption (405–472 μg/kg) or lipid model (74.5–149.6 μg/kg) for carp , indicating the uptake of TBT and TPT did not only depend on lipids but also oxygen ligands or macromolecules such as amino acids and proteins of the living organism. In contrast, the apparent C bio values (149.1–926.4 μg/kg) of both TBT and TPT were lower than that of estimated by sorption model (1341–1902 μg/kg) for C. demersum , which were due to the rapid metabolic rate of them, especially for TBT. But no relation was observed between TBT and TPT concentrations and lipid contents in C. demersum. • TBT and TPT exhibited a high affinity but a low speed of metabolism in carp. (79 characters). • C. demersum had a faster metabolism either for TBT or TPT than carp. (66 characters). • C. demersum can rapidly uptake and metabolize TBT and TPT. (61 characters). • Uptake limit of carp to OTC predicted by equilibrium sorption will be underestimated. (84 characters). [ABSTRACT FROM AUTHOR]