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Simple Summary: Strong ultraviolet radiation is an extreme environmental characteristic of the Tibetan Plateau. Melanin is the most important light-protective substance that allows fish to resist ultraviolet radiation. In order to explore the melanin protection mechanism of fish in the Tibetan Plateau against strong ultraviolet radiation, Triplophysa stenura distributed in high elevation areas was selected as the research object. Transcriptome differences were compared between skin and peritoneal wall layers with different melanin contents to explore the regulatory genes related to melanin synthesis. This provides basic data for analyzing the molecular mechanism of melanin protection in plateau fish against strong ultraviolet radiation. The results indicate that a total of twenty-three DEGs are enriched in the melanin synthesis pathway by a local Blast comparison, of which nine DEGs are significantly upregulated in the peritoneal wall layer and six DEGs are significantly upregulated in the dorsal and lateral skin. The results suggest that these genes may be associated with the molecular mechanism of melanin synthesis in T. stenura, and the differential regulation of genes may be related to the differences in the UVR intensity and tissue sites of melanin synthesis. Further investigation is needed to determine how these genes specifically regulate melanin synthesis. A total of 81,868 All-Unigenes were sequenced and assembled by the transcriptome in the dorsal skin, the lateral skin, and the peritoneal wall layer of Triplophysa stenura with a total assembly length of 123,827,585 bp, and 68,750 unigenes were annotated to seven functional databases. A total of 588 DEGs were screened between the dorsal and lateral skin, 17,097 DEGs were screened between the dorsal skin and the peritoneal wall layer, and 16,598 DEGs were screened between the lateral skin and the peritoneal wall layer. Most of DEGs in three tissues were annotated to GO terms related to cellular structures, binding, cellular processes, and catalytic activity. They were also annotated to KEGG pathways such as the MAPK signaling pathway, PI3K-Akt signaling pathway, Wnt signaling pathway, melanogenesis, tyrosine metabolism, and cell cycle. A total of twenty-three DEGs were found to be enriched in the melanin synthesis pathway by a local Blast comparison, of which nine DEGs were significantly upregulated in the peritoneal wall layer and six DEGs were significantly upregulated in the dorsal and lateral skin. The results suggest that these genes may be associated with the molecular mechanism of melanin synthesis in T. stenura, and the differential regulation of genes may be related to the differences in UVR intensity and tissue sites of melanin synthesis. Further investigation is needed on how these genes specifically regulate melanin synthesis. [ABSTRACT FROM AUTHOR]

Chemical nutrient amendment by human activities can lead to environmental impacts contributing to global biodiversity loss. However, the comprehensive understanding of how below- and above-ground biodiversity shifts under fertilization regimes in natural ecosystems remains elusive. Here, we conducted a seven-year field experiment (2011–2017) and examined the effects of different fertilization on plant biodiversity and soil belowground (prokaryotic and eukaryotic) communities in the alpine meadow of the Tibetan Plateau, based on data collected in 2017. Our results indicate that nitrogen addition promoted total plant biomass but reduced the plant species richness. Conversely, phosphorus enrichment did not promote plant biomass and exhibited an unimodal pattern with plant richness. In the belowground realm, distinct responses of soil prokaryotic and eukaryotic communities were observed under fertilizer application. Specifically, soil prokaryotic diversity decreased with nitrogen enrichment, correlating with shifts in soil pH. Similarly, soil eukaryotic diversity decreased with increased phosphorous inputs, aligning with the equilibrium between soil available and total phosphorus. We also established connections between these soil organism communities with above-ground plant richness and biomass. Overall, our study contributes to a better understanding of the sustainable impacts of human-induced nutrient enrichment on the natural environment. Future research should delve deeper into the long-term effects of fertilization on soil health and ecosystem functioning, aiming to achieve a balance between agricultural productivity and environmental conservation. • Soil prokaryotic and eukaryotic diversity decreased under nitrogen and phosphorus fertilization respectively. • Phosphorus fertilizer can alleviate nitrogen fertilizer induced soil acidification and promote soil diversity. • The changes of soil biodiversity were attributed to soil physicochemical characteristics induced by different fertilizer. • Soil prokaryotes and eukaryotes diversity was linked with the plant richness and biomass respectively. [ABSTRACT FROM AUTHOR]

The northernmost margin of East Asian summer monsoon (EASM) could well reflect wet/dry climate variability in the EASM marginal zone (northern China). The study shows that EASM occurs in northern China from Meiyu period to midsummer, and it is also the advancing period of the northern margin of EASM (NMEASM) before the 43rd pentad. NMEASM activity exhibits multi-scale variability, at cycles of 2–3-yr, 4–6-yr and 9–12-yr, which respond not only to EASM intensity but also to westerly circulation anomaly, exhibiting the mid-latitude Eurasian waves and the high-latitude Eurasian teleconnection (EU) patterns. The positive anomalies of Silk Road pattern and EU pattern in recent two decades contribute to the enhanced west-ridge and east-trough anomaly around 120°E over northern China, leading to divergence of moisture flux and north wind anomaly, which is helpful for southward western pacific subtropical high (WPSH) and southward NMEASM. Negative Eurasian pattern along subtropical Jet leads to anticyclone anomaly over south of the Yangtze River, deep trough and north wind anomaly along the west coast of the subtropical Pacific, contributing to southward WPSH and NMEASM at the cycle of 4–6-yr. Remote forcing sources of these anomalous Eurasian waves include North Europe, north of Caspian Sea, Central Asia, Tibetan Plateau and the west of Lake Baikal; the south of Lake Baikal is a local forcing region. The Tibetan Plateau heating and snow cover could modulate Eurasian wave pattern at multi-scale, which could be used as prediction reference of multi-scale NMEASM. [ABSTRACT FROM AUTHOR]

The Himalayan leucogranite occurs as two extensive (>1000 km) E-W trending belts on the Tibetan Plateau with the unique features. The leucogranite comprised biotite granite, two-mica/muscovite granite, tourmaline granite and garnet granite, which have been identified in previous studies, as well as albite granite and granitic pegmatite that were identified in this investigation. Fifteen leucogranite plutons were studied and 12 were found to contain rare-metal bearing minerals such as beryl (the representative of Be mineralization), columbite-group minerals, tapiolite, pyrochlore-microlite, fergusonite, Nb-Ta rutile (the representative of Nb-Ta mineralization), and cassiterite (the representative of Sn mineralization) mainly based on the field trip, microscope observation and microprobe analysis. The preliminary result shows that the Himalayan leucogranite is commonly related to the rare-metal mineralization and warrants future investigation. Further exploration and intensive research work is important in determining the rare-metal resource potential of this area. [ABSTRACT FROM AUTHOR]

Sixteen soil samples were collected from the central Tibetan Plateau (CTP). The soil concentrations of polybrominated diphenyl ethers (PBDEs) in CTP were analyzed. The detected 42 congeners were divided into light, intermediate and heavy fractions. In addition to the various minerals, other soil properties were also characterized, including the content of soil organic carbon (SOC) and the particle size distribution. The clay content is positively related to the intermediate fraction of the PBDEs and negatively related to the light and heavy fractions. Similar correlations were observed for SOC and the fine-particle fraction (size < 2 μm). The coefficient of determination (r 2) associated with a linear regression indicated that the clays were more highly correlated with the fractional pattern of the PBDEs than with the other properties, such as SOC and the fine-particle fraction. The values of r 2 between clays and three fractions of PBDEs are 0.70, 0.69 and 0.58. [Copyright &y& Elsevier]