Leaf ecological stoichiometry and anatomical structural adaptation mechanisms of Quercus sect. Heterobalanus in southeastern Qinghai-Tibet Plateau.

BACKGROUND: With the dramatic uplift of the Qinghai-Tibet Plateau (QTP) and the increase in altitude in the Pliocene, the environment became dry and cold, thermophilous plants that originally inhabited ancient subtropical forest essentially disappeared. However, Quercus sect. Heterobalanus (QSH) have gradually become dominant or constructive species distributed on harsh sites in the Hengduan Mountains range in southeastern QTP, Southwest China. Ecological stoichiometry reveals the survival strategies plants adopt to adapt to changing environment by quantifying the proportions and relationships of elements in plants. Simultaneously, as the most sensitive organs of plants to their environment, the structure of leaves reflects of the long-term adaptability of plants to their surrounding environments. Therefore, ecological adaptation mechanisms related to ecological stoichiometry and leaf anatomical structure of QSH were explored. In this study, stoichiometric characteristics were determined by measuring leaf carbon (C), nitrogen (N), and phosphorus (P) contents, and morphological adaptations were determined by examining leaf anatomical traits with microscopy. RESULTS: Different QSH life forms and species had different nutrient allocation strategies. Leaves of QSH plants had higher C and P and lower N contents and higher N and lower P utilization efficiencies. According to an N: P ratio threshold, the growth of QSH species was limited by N, except that of Q. aquifolioides and Q. longispica, which was limited by both N and P. Although stoichiometric homeostasis of C, N, and P and C: N, C: P, and N: P ratios differed slightly across life forms and species, the overall degree of homeostasis was strong, with strictly homeostatic, homeostatic, and weakly homeostatic regulation. In addition, QSH leaves had compound epidermis, thick cuticle, developed palisade tissue and spongy tissue. However, leaves were relatively thin overall, possibly due to leaf leathering and lignification, which is strategy to resist stress from UV radiation, drought, and frost. Furthermore, contents of C, N, and P and stoichiometric ratios were significantly correlated with leaf anatomical traits. CONCLUSIONS: QSH adapt to the plateau environment by adjusting the content and utilization efficiencies of C, N, and P elements. Strong stoichiometric homeostasis of QSH was likely a strategy to mitigate nutrient limitation. The unique leaf structure of the compound epidermis, thick cuticle, well-developed palisade tissue and spongy tissue is another adaptive mechanism for QSH to survive in the plateau environment. The anatomical adaptations and nutrient utilization strategies of QSH may have coevolved during long-term succession over millions of years.

Comparative analysis of phytochemical profile and antioxidant and anti-inflammatory activity of four Gentiana species from the Qinghai-Tibet Plateau.

ETHNOPHARMACOLOGICAL RELEVANCE: Gentiana species, known as the traditional Tibetan medicine "Bangjian," have been integral to clinical practice for millennia. Despite their longstanding use, our understanding of the variation in chemical constituents and bioactive effects among different species is limited. AIM OF THE STUDY: In the present study, we aimed to assess the differences in chemical profiles and bioactivities among four Gentiana species (G. veitchiorum, G. trichotoma, G. crassuloides, and G. squarrosa) and explore potential bioactive markers. MATERIALS AND METHODS: The chemical composition of the four Gentiana species was analyzed using UPLC-QE-Orbitrap-MS. The antioxidant activity of the extracts was compared through DPPH, ABTS, and reducing power assays. The anti-inflammatory activity was evaluated by measuring the inhibitory effects on lipopolysaccharide-induced secretion of nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) by RAW264.7 macrophages. Additionally, compounds strongly correlated with anti-inflammatory and antioxidant activities were identified through spectrum-effect relationship analysis. RESULTS: A total of 50 compounds were identified across the four Gentiana species. In vitro antioxidant assays demonstrated DPPH and ABTS scavenging abilities and reducing power within the concentration range of 62.5-2000 µg/mL. All four species inhibited the production of NO, IL-6, and TNF-α in RAW264.7 cells. Spectrum-effect relationship analysis revealed that gentiascabraside A, gentiatibetine, tachioside, lutonarin, and isotachioside were associated with the highest antioxidant activity; and swertiamarin, tarennoside, eleganoside C, and alpigenoside were associated with the highest anti-inflammatory activity. CONCLUSIONS: This study presents, for the first time, the chemical profiles and bioactivities of G. trichotoma, G. crassuloides, and G. squarrosa, which were comprehensively compared with those of G. veitchiorum. The findings provide novel insights to understand the traditional use and/or expand the current use of Gentiana species. Additionally, this research highlights the potential of Gentiana species as natural sources of antioxidants and anti-inflammatory agents, suggesting promising applications in tea production or medicinal contexts in the near future.

Chromosome level genome assembly of endangered medicinal plant Anisodus tanguticus.

Anisodus tanguticus is a medicinal herb that belongs to the Anisodus genus of the Solanaceae family. This endangered herb is mainly distributed in Qinghai-Tibet Plateau. In this study, we combined the Illumina short-read, Nanopore long-read and high-throughput chromosome conformation capture (Hi-C) sequencing technologies to de novo assemble the A. tanguticus genome. A high-quality chromosomal-level genome assembly was obtained with a genome size of 1.26 Gb and a contig N50 of 25.07 Mb. Of the draft genome sequences, 97.47% were anchored to 24 pseudochromosomes with a scaffold N50 of 51.28 Mb. In addition, 842.14 Mb of transposable elements occupying 66.70% of the genome assembly were identified and 44,252 protein-coding genes were predicted. The genome assembly of A. tanguticus will provide genetic repertoire to understand the adaptation strategy of Anisodus species in the plateau, which will further promote the conservation of endangered A. tanguticus resources.

Short-term robust plant overcompensatory growth was observed in a degraded alpine meadow on the southeastern Qinghai-Tibetan Plateau.

Plant overcompensatory growth (OCG) is an important mechanism by which plant communities adapt to environmental disturbance. However, it is not clear whether plant OCG can occur in degraded alpine meadows. Here, we conducted a mowing experiment in an alpine meadow at three degradation levels (i.e., severe degradation, SD; moderate degradation, MD; and light degradation, LD) on the southeastern Qinghai-Tibetan Plateau from 2018 to 2020 to investigate plant OCG and its relationships with soil available nutrients, plant nutrient use efficiency (i.e., nitrogen use efficiency, NUE; and phosphorus use efficiency, PUE), and precipitation. The results showed that 1) the OCG of the plant community generally occurred across all degradation levels, and the OCG strength of the plant community decreased with mowing duration. Moreover, the OCG strength of the plant community in the SD treatment was significantly greater than that in the MD and LD treatments after two years of mowing (p < 0.05). 2) In LD and MD, the soil nitrate nitrogen (NO3-) and available phosphorus (AP) concentrations exhibited a decreasing trend (p < 0.05), while the soil ammonium nitrogen (NH4+) concentration did not change from 2018 to 2020 (p > 0.05). In the SD treatment, the soil NO3- concentration tended to decrease (p < 0.05), the NH4+ concentration tended to increase (p < 0.05), and the AP concentration exhibited an inverse parabolic trend (p < 0.05) from 2018 to 2020. 3) From 2018 to 2020, plant NUE and PUE exhibited decreasing trends at all degradation levels. 4) Plant nutrient use efficiency, which is regulated by complex plant-soil interactions, strongly controlled the OCG of the plant community along each degradation gradient. Moreover, precipitation not only directly promoted the OCG of the plant community but also indirectly affected it by regulating the structure of the plant community and plant nutrient use efficiency. These results suggest that the OCG of the plant community in degraded alpine meadows may benefit not only from the strong self-regulating capacity of the plant-soil system but also from humid climatic conditions.

Microflora structure and functional capacity in Tibetan kefir grains and selenium-enriched Tibetan kefir grains: A metagenomic analysis.

Tibetan kefir grains (TKGs) are a complex protein-lipid-polysaccharide matrix composed of various microorganisms. Microorganisms have the benefit of being effective, secure, and controllable when used for selenium enrichment. In this study, selenium-enriched Tibetan kefir grains (Se-TKGs) were made, and the microbiology composition was analyzed through a metagenomic analysis, to explore the influence of selenium enrichment. The microbial composition of TKGs and Se-TKGs, as well as the probiotic species, quorum sensing system (QS) and functional genes were compared and evaluated. Lactobacillus kefiranofaciens was the most abundant microbial species in both communities. Compared with TKGs, Se-TKGs had a much higher relative abundance of acetic acid bacteria. Lactobacillus helveticus was the most common probiotic species both in TKGs and Se-TKGs. Probiotics with antibacterial and anti-inflammatory properties were more abundant in Se-TKGs. QS analysis revealed that Se-TKGs contained more QS system-associated genes than TKGs. Moreover, Kyoto Encyclopedia of Genes and Genomes analysis revealed that the pathway for human disease ko01501 had the greatest relative abundance in both TKGs and Se-TKGs. Compared with TKGs, Se-TKGs demonstrated a greater relative abundance of different drug resistance-related metabolic pathways. Additionally, linear discriminant analysis effect size was used to examine the biomarkers responsible for the difference between the two groups. In this study, we focused on the microbiological structure of TKGs and Se-TKGs, with the aim of establishing a foundation for a more thorough investigation of Se-TKGs and providing a basis for exploring potential future use.

Available sulfur and phosphorus transformation mechanism and functional microorganisms during sheep manure composting on Qinghai-Tibet Plateau under two moisture contents.

Understanding the mechanisms of sulfur and phosphorus transformation during composting is important for improving compost fertility. This study aims to investigate the microbial mechanism of available sulfur and phosphorus transformation during sheep manure composting under different moisture contents (45%: M45 and 60%: M60) on the Qinghai-Tibet Plateau using metagenomics technology. The results showed that the final available sulfur and phosphorus contents of M45 were 11% and 13% higher than those of M60, respectively. M45 enhanced sulfur oxidation, sulfate reduction, and thiosulfate disproportionation. These steps were significantly positively correlated with available sulfur, and Pseudomonas, Thermobifida, Luteimonas, Brevibacterium, Planifilum, and Xinfangfangia were the main participants. Available phosphorus was significantly positively correlated with polyphosphate degradation and inorganic P solubilization, and the main participants in these steps were Luteimonas, Brachybacterium, Corynebacterium, Jeotgalicoccus, Microbacterium, Streptomyces, and Pseudoxanthomonas. These findings reveal the microbial mechanisms of available and phosphorus transformation during composting at two moisture contents.

The Tibetan Formula Cong zhi 6 in the ORL (ENT) Practice: Experiences with Laryngopharyngeal Reflux.

BACKGROUND: Laryngopharyngeal reflux (LPR) is a frequent condition; in European countries, the prevalence can be estimated as 10-30% of the general population. Treatment includes lifestyle measures and highly dosed proton pump inhibitors (PPIs) over at least 4 weeks. However, PPIs are not unproblematic due to their potential side effects and the known phenomenon of rebound acid hypersecretion. Cong zhi 6 is a multi-herbal Tibetan formula additionally containing calcium carbonate and is available in several European countries as a food supplement Padma Aciben/Padma AciTib. CASE REPORT: Ten patients with LPR took Cong zhi 6. The course of the complaints was documented, and the data were retrospectively analysed. Clinical symptoms as assessed with the Reflux Symptom Index (RSI) questionnaire and the findings in laryngoscopy with the Reflux Finding Score (RFS) both showed marked improvement of several symptoms. The number of patients with pathological LPR sum score was significantly reduced from 8 to 2 patients and from 10 to 1 patient in RSI and RFS, respectively. The mean sum scores were reduced from 18.1 to 8.4 (RSI) and from 12.9 to 4.4 (RFS), respectively. Also, other gastrointestinal symptoms, such as abdominal pain, bloating, feeling of fullness, and nausea, which are usually associated with functional dyspepsia and irritable bowel syndrome, were markedly improved (reduction of mean score of the 3 most frequent symptoms by 77-87%). CONCLUSION: Standard medical treatment for LPR consists in high dosed PPI for at least 4 weeks, which is known for several side effects and does not treat reliable the nonacid component of LPR of pepsin or other gastric enzymes. Therefore, other medical treatment options are urgently needed. The promising data of this case series suggest that the Tibetan herbal formula Cong zhi 6 may be a treatment option in LPR and related gastrointestinal symptoms and warrant further research.Der laryngopharyngeale Reflux (LPR) ist eine häufige Erkrankung. In europäischen Ländern wird die Prävalenz in der Gesamtbevölkerung auf 10­30% geschätzt. Die Behandlung beinhaltet Ernährungs- und Verhaltensänderung sowie die Gabe hochdosierter Protonen-Pumpen-Hemmer (PPI) über mindestens 4 Wochen. PPI sind jedoch aufgrund ihrer hohen potenziellen Nebenwirkungen und des bekannten Rebound-Phänomens der sauren Magensafthypersekretion nicht unproblematisch. Cong zhi 6 ist eine tibetische Rezeptur aus einem Vielpflanzengemisch sowie zusätzlich Calciumcarbonat und ist in einigen europäischen Ländern als Nahrungsergänzungsmittel Padma Aciben/Padma AciTib erhältlich.Zehn Patienten mit laryngo-pharyngealem Reflux (LPR) nahmen Cong zhi 6 ein. Der Beschwerdeverlauf wurde dokumentiert und die Daten retrospektiv analysiert. Die klinischen Symptome, die mithilfe des Reflux Symptom Index (RSI) Fragebogens erfasst wurden und die mittels des Reflux Finding Score (RFS) beurteilten laryngoskopischen Befunde zeigten beide eine deutliche Verbesserung verschiedener Symptome. Die Zahl der Patienten mit pathologischen LPR-Summenscore reduzierte sich signifikant, im RSI von 8 auf 2 und im RFS von 10 auf 1 Patienten. Der mittlere Summenwert sank von 18.1 auf 8.4 (RSI) und von 12.9 auf 4.4 (RFS). Des Weiteren zeigte sich auch bei anderen gastrointestinalen Beschwerden, wie Bauchschmerzen, Blähungen, Völlegefühl und Übelkeit, die normalerweise mit funktioneller Dyspepsie oder Reizdarm zusammenhängen, eine deutliche Verbesserung (durchschnittliche Verringerung des Scores der drei häufigsten Symptome um 77­87%).Die medikamentöse Standardbehandlung bei LPR besteht aus der hochdosierten PPI-Gabe über mindestens 4 Wochen, die jedoch für verschiedene Nebenwirkungen bekannt ist und die nicht-saure Komponente von LPR, wie Pepsin oder andere digestive Enzyme, nicht mitbehandelt. Daher sind andere medikamentöse Behandlungsmöglichkeiten dringend erforderlich. Die vielversprechenden Daten dieser Fallserie deuten darauf hin, dass die tibetische Pflanzenrezeptur Cong zhi 6 eine Behandlungsoption bei LPR sowie deren gastrointestinalen Symptome darstellt und rechtfertigen weitere Studien.

Fat deposition, fatty acid profiles, antioxidant capacity and differentially expressed genes in subcutaneous fat of Tibetan sheep fed wheat-based diets with and without xylanase supplementation.

Xylanase, an exogenous enzyme that plays an essential role in energy metabolism by hydrolysing xylan into xylose, has been shown to positively influence nutrient digestion and utilisation in ruminants. The objective of this study was to evaluate the effects of xylanase supplementation on the back-fat thickness, fatty acid profiles, antioxidant capacity, and differentially expressed genes (DEGs) in the subcutaneous fat of Tibetan sheep. Sixty three-month-old rams with an average weight of 19.35 ± 2.18 kg were randomly assigned to control (no enzyme added, WH group) and xylanase (0.2% of diet on a dry matter basis, WE group) treatments. The experiment was conducted over 97 d, including 7 d of adaption to the diets. The results showed that xylanase supplementation in the diet increased adipocyte volume of subcutaneous fat (p < 0.05), shown by hematoxylin and eosin (H&E) staining. Gas chromatography showed greater concentrations of C14:0 and C16:0 in the subcutaneous fat of controls compared with the enzyme-treated group (p < 0.05), while opposite trend was seen for the absolute contents of C18:1n9t, C20:1, C18:2n6c, C18:3, and C18:3n3 (p < 0.05). Compared with controls, supplementation with xylanase increased the activity of T-AOC significantly (p < 0.05). Transcriptomic analysis showed the presence of 1630 DEGs between the two groups, of which 1023 were up-regulated and 607 were down-regulated, with enrichment in 4833 Gene Ontology terms, and significant enrichment in 31 terms (p < 0.05). The common DEGs were enriched in 295 pathways and significantly enriched in 26 pathways. Additionally, the expression of lipid-related genes, including fatty acid synthase, superoxide dismutase, fatty acid binding protein 5, carnitine palmytoyltransferase 1 A, and peroxisome proliferator-activated receptor A were verified via quantitative reverse-transcription polymerase chain reaction. In conclusion, dietary xylanase supplementation was found to reduce subcutaneous fat deposition in Tibetan sheep, likely through modulating the expression of lipid-related genes.

Tibetan tea consumption prevents obesity by modulating the cellular composition and metabolic reprogramming of white adipose tissue.

Obesity, a global health concern, is linked with numerous metabolic and inflammatory disorders. Tibetan tea, a traditional Chinese beverage rich in theabrownin, is investigated in this study for its potential anti-obesity effects. Our work demonstrates that Tibetan tea consumption in C57BL/6J mice significantly mitigates obesity-related phenotypic changes without altering energy intake. Computational prediction revealed that Tibetan tea consumption reconstructs gene expression in white adipose tissue (WAT), promoting lipid catabolism and thereby increasing energy expenditure. We also note that Tibetan tea suppresses inflammation in WAT, reducing adipocyte hyperplasia and immune cell infiltration. Furthermore, Tibetan tea induces profound metabolic reprogramming, influencing amino acid metabolic pathways, specifically enhancing glutamine synthesis, which in turn suppresses pro-inflammatory chemokine production. These findings highlight Tibetan tea as a potential candidate in obesity prevention, providing a nuanced understanding of its capacity to modulate the cellular composition and metabolic landscape of WAT.

Effects of dietary wheat supplementation levels on growth performance, rumen bacterial community and fermentation parameters in Chinese Tibetan Sheep.

The objective of this study was to evaluate various wheat supplementation levels on rumen microbiota and fermentation parameter in Tibetan sheep. A total of ninety ram with an average 12.37 ± 0.92 kg at the age of 2 months were randomly allocated to three treatments: 0% wheat diet (CW, N = 30), 10% wheat diet (LW, N = 30), and 15% wheat diet (HW, N = 30) on a dry matter basis. The experiment was conducted over a period of 127 days, including 7 days of adaption to the diets. Our results showed that sheep fed 10% wheat exhibited optimal average daily gain and feed gain ratio compared with HW group (p < 0.05). The serum alkaline phosphatase concentration was the lowest when fed the 10% wheat diet (p < 0.05), whereas serum aspartate aminotransferase concentration was the highest (p < 0.05). Both acetate and propionate increased with increase in dietary wheat ratio (p < 0.05), while a greater decrease in concentrations of NH3 -N was observed (p < 0.05). In rumen fluid, 3413 OTUs were obtained with 97% consistency. Phylum Firmicutes was the predominant bacteria and accounted for 49.04%. The CW groups supported significantly increased the abundance of Bacteroidetes (p < 0.05), as compared with the HW group. The abundance of Bacteroidales_UCG-001, Ruminococcus, and Mitsuokella possessed a higher relative abundance in HW group (p < 0.05). No differences in the bacterial community and fermentation parameters were observed between the sheep fed 0% and 10% wheat (p > 0.05). Ruminal bacterial community structure was significantly correlated with isobutyrite (r2 = 0.4878, p = 0.035) and valerate (r2 = 0.4878, p = 0.013). In conclusion, supplementation of 10% wheat in diet promoted the average daily gain and never altered microbial community structure and fermentation pattern, which can be effectively replace partial corn in Chinese Tibetan Sheep.

Gut microbiota and metabolic modulation by supplementation of polysaccharide-producing Bacillus licheniformis from Tibetan Yaks: A comprehensive multi-omics analysis.

Gut microbiota and their metabolic processes depend on the intricate interplay of gut microbiota and their metabolic processes. Bacillus licheniformis, a beneficial food supplement, has shown promising effects on stabilizing gut microbiota and metabolites. However, the precise mechanisms underlying these effects remain elusive. In this study, we investigated the impact of polysaccharide-producing B. licheniformis as a dietary supplement on the gut microbiome and metabolites through a combination of scanning electron microscopy (SEM), histological analysis, high-throughput sequencing (HTS), and metabolomics. Our findings revealed that the B. licheniformis-treated group exhibited significantly increased jejunal goblet cells. Moreover, gut microbial diversity was lower in the treatment group as compared to the control, accompanied by noteworthy shifts in the abundance of specific bacterial taxa. Enrichment of Firmicutes, Lachnospiraceae, and Clostridiales_bacterium contrasted with reduced levels of Campylobacterota, Proteobacteria, Parasutterella, and Helicobacter. Notably, the treatment group showed significant weight gain after 33 days, emphasizing the polysaccharide's impact on host metabolism. Delving into gut metabolomics, we discovered significant alterations in metabolites. Nine metabolites, including olprinone, pyruvic acid, and 2-methyl-3-oxopropanoate, were upregulated, while eleven, including defoslimod and voclosporin were down-regulated, shedding light on phenylpropanoid biosynthesis, tricarboxylic acid cycle (TCA cycle), and the glucagon signaling pathway. This comprehensive multi-omics analysis offers compelling insights into the potential of B. licheniformis as a dietary polysaccharide supplement for gut health and host metabolism, promising significant implications for gut-related issues.

[Analysis of diet structure of Kashin-beck disease area in Chamdo-Lhorong of Tibet in 2021].

OBJECTIVE: To investigate and compare the dietary structure between healthy people and patients in KBD area of Chamdo-Lhorong of Tibet. METHODS: A case-control study design was used, retrospectively select patients who had completed screening and registered in the national Kashin-Beck Disease surveillance system in 2021 in Luolong County, Qamdo, Tibet as the source population of the case group, and randomly selected people who had not been screened for Kashin-Beck disease in the same county as the control group. The self-made diet questionnaire was used to record the types of food consumption, frequency of food intake, basic information of the respondents, family size and other basic information in the past year by one-on-one interview. RESULTS: The staple food with the highest response among the patients(97.33%) was rice(rice/rice noodle), and the highest response among the healthy people(90%) was non-wheat products, non-fried pasta(bread/steamed bun/noodles/dumplings), except instant noodles.78.7% of patients chose not to eat local wheat(Tibetan noodles), and the number of non-patients who chose to eat non-local wheat(Tibetan noodles) 3-4 times a week was significantly higher than that of patients. The meat and meat products with the highest response in both patients(93.33%) and healthy people(90%) was yak meat(local). The control group also chose to consume beef(non-local/lamb/mutton/other non-processed meat), poultry and livestock offal, fish(all seawater and freshwater fish), shrimp and crabs or other seafood, and their consumption rate and intake frequency were significantly higher than those of the case group. The consumption rate and frequency of tomato, onion and garlic(garlic shoots/leek/onion/onion) and fresh eggs(egg/duck egg/quail egg/goose egg) in control group were significantly higher than those in case group. There was no significant difference in consumption rate and frequency of fruits, milk and dairy products between the two groups. CONCLUSION: In addition to the local highland barley(zanba), most people also chose to purchase rice and flour, which changed the situation of single staple food in the past. However, compared with the healthy population in the disease area, the consumption rate and intake frequency of fish, shrimp and crabs, poultry and livestock viscera, eggs(fresh eggs) and vegetables(tomatoes, scallions, ginger and garlic) in KBD patients were significantly lower, the selection of meat varieties is single, mainly local yak meat, and the overall dietary structure still presents the risk of single type and unbalanced diet.

Black Goji Berry (Lycium ruthenicum Murray): A Review of Its Pharmacological Activity.

Lycium ruthenicum Murray (LRM; commonly known as black goji berry or black wolfberry), a plant in the Solanaceae family, grows in the deserts of China's Qinghai-Tibet plateau. LRM is widely consumed in traditional Chinese medicine, and its fruits are frequently used as herbal remedies to treat heart disease, fatigue, inflammation, and other conditions. Many studies have reported that LRM is rich in functional phytochemicals, such as anthocyanins and polysaccharides, and has various pharmacological actions. This article reviews research on the biological and pharmacological effects of the constituents of LRM fruits. LRM has various pharmacological properties, such as antioxidant, anti-inflammatory, anti-radiation, immune-enhancing, anti-tumor, and protective effects. LRM has much promise as a dietary supplement for preventing many types of chronic metabolic disease.

An ethnobotanical study of wild edible plants used by the Tibetan in the Rongjia River Valley, Tibet, China.

BACKGROUND: Wild edible plants (WEPs) play a crucial role in communities with limited communication with the outside world, where unstable factors, such as poor food supply and insufficient access to timely nutritional supplementation, are common, as in the Himalayan region. To document the traditional knowledge of WEPs and explore their significance for communities with minimal global economic exchange, an ethnobotanical study was conducted in the town of Rongjia, which lies in a narrow valley near Mount Everest, Tibet, China. METHODS: This ethnobotanical study was conducted in three villages in the Rongjia River Valley between August 2021 and June 2023. Semi-structured interviews and participatory observations were used to collect information on WEPs. The fieldwork was performed with the assistance of local guides. Voucher specimens were collected from each documented plant species for taxonomic identification. We used the use report (UR) and relative frequency of citations (RFC) to evaluate the comprehensive utilization value of WEPs. RESULTS: We interviewed 161 informants who provided us with 2499 use reports. We collected 50 WEPs belonging to 28 families and 42 genera used by the Tibetan people in the Rongjia River Valley. WEPs are used in vegetables, fruits, seasonings, healthcare foods, substitute grains, and beverages. Wild vegetables were the most commonly used, followed by wild fruits. Leaves were the most commonly consumed part of the plant. The three most important WEPs ordered by RFC values were Rosa sericea var. glandulosa Osmaston (RFC = 0.76), Zanthoxylum bungeanum Maxim. (RFC = 0.75), and Urtica hyperborea Jacquem. ex Wedd. (RFC = 0.71). Other than that, we also document some of WEPs used in the past. Arisaema erubescens Schott, Pinellia ternata (Thunb.) Makino, and Satyrium nepalense var. ciliatum (Lindl.) Hook. f. used to serve as important substitute grains, are no longer in use, however, they remain vivid in the memories of older people. CONCLUSIONS: WEPs included wild vegetables, fruits, seasonings, healthcare food, and substitute grains for Tibetan people in the Rongjia River Valley. Some WEPs have become important cultural symbols for older people, which can help in understanding the relationship between plants and local people in the past. In addition, WEPs can increase the resilience of local people living in remote areas when facing sudden destabilizing events in future. This is the significance of WEPs for communities with minimal global economic exchange. Therefore, we suggest that future studies focus more on WEPs in communities with limited communication with the world to improve their resilience.

Asymmetric response of aboveground and belowground temporal stability to nitrogen and phosphorus addition in a Tibetan alpine grassland.

Anthropogenic eutrophication is known to impair the stability of aboveground net primary productivity (ANPP), but its effects on the stability of belowground (BNPP) and total (TNPP) net primary productivity remain poorly understood. Based on a nitrogen and phosphorus addition experiment in a Tibetan alpine grassland, we show that nitrogen addition had little impact on the temporal stability of ANPP, BNPP, and TNPP, whereas phosphorus addition reduced the temporal stability of BNPP and TNPP, but not ANPP. Significant interactive effects of nitrogen and phosphorus addition were observed on the stability of ANPP because of the opposite phosphorus effects under ambient and enriched nitrogen conditions. We found that the stability of TNPP was primarily driven by that of BNPP rather than that of ANPP. The responses of BNPP stability cannot be predicted by those of ANPP stability, as the variations in responses of ANPP and BNPP to enriched nutrient, with ANPP increased while BNPP remained unaffected, resulted in asymmetric responses in their stability. The dynamics of grasses, the most abundant plant functional group, instead of community species diversity, largely contributed to the ANPP stability. Under the enriched nutrient condition, the synchronization of grasses reduced the grass stability, while the latter had a significant but weak negative impact on the BNPP stability. These findings challenge the prevalent view that species diversity regulates the responses of ecosystem stability to nutrient enrichment. Our findings also suggest that the ecological consequences of nutrient enrichment on ecosystem stability cannot be accurately predicted from the responses of aboveground components and highlight the need for a better understanding of the belowground ecosystem dynamics.

Change characteristics and influencing factors of grassland degradation in adjacent areas of the Qinghai-Tibet Plateau and suggestions for grassland restoration.

Natural grasslands are being progressively degraded around the world due to climate change and socioeconomic factors. Most of the drivers, processes, and consequences of grassland degradation are studied separately, and it is not yet clear whether the change characteristics and influence factors of adjacent areas of grassland are identical. We analyzed changes in grassland area and quality, and the influences of climate changes and socioeconomic factors from 1980-2018 in Maqu County, Xiahe County and Luqu County on the eastern Qinghai-Tibet Plateau (QTP). We found that areas with high and medium coverage grassland in Maqu County and Luqu County decreased continuously with time, while low coverage grassland areas increased in three counties. In Xiahe County, the medium coverage grassland area reduced with time (except for 2010), while the high and low coverage grassland areas increased. The actual net primary productivity of the three counties showed a downward trend. In Maqu County, the total grassland area had an extremely significant positive correlation with number of livestock going to market, commodity rate, gross domestic product (GDP), primary industry, tertiary industry, household density, and levels of junior middle school education and university education in the area. In Luqu County, the total grassland area high coverage grassland area were significantly negatively correlated with total number of livestock, secondary industry, levels of primary school education, and temperature. Ecological education was positively correlated with high coverage grassland, and negatively correlated with low coverage grassland in all three areas. The results of this study suggest that the best ways to restore the area and quality of grasslands in these areas would be to reduce the local cultivated land area and slow down the development of the primary and tertiary industries in Maqu County, and to control industry development and the total number of livestock in Luqu County. This study also suggests that improving education level and strengthening the level of ecological education are conducive to the restoration of grasslands.

Ephedrine and pseudoephedrine in Ephedra saxatilis on the vertical altitude gradient changed in southern Tibet Plateau, China.

Ephedra is one of the world's most important plants, used in medicine, plants and ecology. Most Ephedra grows in plain areas and is stable. But the plateau environment is special, with the change of altitude, the variety difference of plateau Ephedra saxatilis is very obvious. E. saxatilis metabolism on the Tibetan Plateau is not only affected by altitude, but also environmental conditions such as climate conditions and different soil components. However, the change mechanism of E. saxatilis alkaloids in special ecological environment is still unclear. Therefore, we analyzed the metabolic and altitude of E. saxatilis species in the Tibetan Plateau. Through the functional analysis of Kyoto Metabolism and Metabolomic Encyclopedia (KEGG), we can determine that the number of E. saxatilis metabolites decreases with the increase of altitude, and there are differences in metabolism among the three mountains. This was confirmed by univariate analysis of the top five metabolic pathways. Based on the analysis of soil and metabolomics, it was found that soil water content was also a factor affecting E. saxatilis metabolism. According to the difference of vertical height gradient, ephedrine and pseudephedrine showed the same change in vertical altitude under different mountains. Ephedrine increased as the altitude gradient increased, and pseudoephedrine decreased as the altitude gradient decreased. Our results provide valuable information for further study of metabolic mechanism and efficacy stability. It provides useful reference for the research of E. saxatilis planting in special area.

Prediction of soil moisture using BiGRU-LSTM model with STL decomposition in Qinghai-Tibet Plateau.

Ali Network data based on the Qinghai-Tibetan Plateau (QTP) can provide representative coverage of the climate and surface hydrometeorological conditions in the cold and arid region of the QTP. Among them, the plateau soil moisture can effectively quantify the uncertainty of coarse resolution satellite and soil moisture models. With the objective of constructing an "end-to-end" soil moisture prediction model for the Tibetan Plateau, a combined prediction model based on time series decomposition and a deep neural network is proposed in this article. The model first performs data preprocessing and seasonal-trend decomposition using loess (STL) to obtain the trend component, seasonal component and random residual component of the original time series in an additive way. Subsequently, the bidirectional gated recurrent unit (BiGRU) is used for the trend component, and the long short-term memory (LSTM) is used for the seasonal and residual components to extract the time series information. The experiments based on the measured data demonstrate that the use of STL decomposition and the combination model can effectively extract the information in soil moisture series using its concise and clear structure. The proposed model in this article has a stable performance improvement of 5-30% over a single model and existing prediction models in different prediction time domains. In long-range prediction, the proposed model also achieves the best accuracy in the shape and temporal domains described by using dynamic time warping (DTW) index and temporal distortion index (TDI). In addition, the generalization performance experiments show that the combined method proposed in this article has strong reference value for time series prediction of natural complex systems.

Modulation of feed digestibility, nitrogen metabolism, energy utilisation and serum biochemical indices by dietary Ligularia virgaurea supplementation in Tibetan sheep.

Ligularia virgaurea is the most widely functional native herbage in the alpine meadow pastures of the Qinghai-Tibet Plateau (QTP) and has multiple pharmacological and biological activities. The effect of L. virgaurea as a dietary component on the digestion and metabolism of sheep was evaluated by conducting feeding trials in metabolic cages. Thirty-two Tibetan yearling rams (29 ± 1.56 kg BW) were randomly allotted to four groups included in a completely randomised design with eight animals per treatment. Sheep were fed a basal diet (freshly native pasture) without the addition of L. virgaurea (control) or with the addition of L. virgaurea (100, 200, or 300 mg/kg BW per day) for 45 days. Addition of L. virgaurea to the diet of Tibetan sheep was found to influence the average daily gain (quadratic [Q], P < 0.001), feed conversion ratio (Q, P = 0.002), CH4 emissions (linear [L], P = 0.029), DM (Q, P = 0.012), neutral detergent fibre (Q, P = 0.017), acid detergent fibre (ADF) (Q, P = 0.027), and ether extract (EE) intake (Q, P = 0.026). Apparently, different levels of L. virgaurea affected the digestibility coefficients of DM, ADF, and EE (L, P > 0.05; Q, P < 0.05). The nitrogen (N) intake (Q, P = 0.001), retained nitrogen (Q, P < 0.001), and N utilisation efficiency (L, P > 0.05; Q, P ≤ 0.001) were also affected by the dietary inclusion of L. virgaurea. Effects of L. virgaurea feeding were also witnessed on methane energy (CH4-E) (L, P = 0.029), gross energy (GE) (Q, P = 0.013), digestible energy (DE) (Q, P = 0.015), and metabolisable energy (ME) intake (Q, P = 0.015). Energy utilisation efficiency expressed as a proportion of GE intake (DE/GE intake, ME/GE intake, ME/DE intake, FE/GE intake, and CH4-E/GE intake) manifested quadratic changes (P < 0.05) with the increase in the L. virgaurea supplementation level. The addition of L. virgaurea increased the activity of superoxide dismutase (Q, P = 0.026) and glutathione peroxidase activity (Q, P = 0.039) in the serum. Overall, the greatest improvement of feed digestibility, N retention, energy utilisation, and antioxidant capacity of Tibetan sheep was yielded by the inclusion of 200 mg/kg BW per day of L. virgaurea. Therefore, the addition of an appropriate amount of L. virgaurea to the diet of Tibetan sheep is safe and natural, and may enhance the sustainability of small ruminant production systems in QTP areas.

Sediment geochemical records of water quality deterioration in lake Jiren, a remote alpine lake on the southeastern margin of the Tibetan Plateau.

Limited human activities in catchments make remote alpine lakes valuable sites for studying the evolution of lake environments in response to climate change and atmospheric deposition; however, this issue remains rarely studied owing to the scarcity of monitoring data. In this study, water quality evolution in Lake Jiren, a remote alpine lake on the southeastern margin of the Tibetan Plateau, over the past two centuries was reconstructed through geochemical analyses of aliphatic hydrocarbons, major and trace elements, and organic matter (OM) pyrolysis products in a dated sediment core, and the associated drivers were identified by temporally comparing the geochemical results with document records. All geochemical data demonstrated that the lake water remained relatively pure until 1947, after which the n-alkane and αß-hopane proxies indicated eutrophication and petroleum contamination. The OM pyrolysis proxy hydrocarbon index indicated more eutrophic conditions after 1957. Concurrently, hypolimnetic deoxygenation increased, as indicated by redox-sensitive proxies, such as the enrichment factors (EFs) of molybdenum (Mo). These proxies recorded further intensification of deoxygenation after 1976. The EFs for other trace elements indicated cadmium contamination after 1967. The greater anthropogenic emissions of reactive nitrogen, petroleum products, and heavy metals in East and South Asia since approximately 1950 and the subsequent atmospheric transport of these materials to the lake might be the basic driver of water quality deterioration. Eutrophication induced by nitrogen deposition was responsible for increased hypolimnetic deoxygenation by enhancing phytoplankton productivity and OM input. The further intensification of deoxygenation was attributed to climate warming since the 1970s, as prolonged water column stratification under this condition decreased oxygen input from the epilimnion to the lake bottom. These findings may be beneficial for understanding the natural and anthropogenic effects on the water quality of alpine lakes and help in the environmental management of Lake Jiren and other alpine lakes.