Qinghai Lake Research Articles

Light grazing increased but heavy grazing decreased the abundance and family richness of soil arthropods community in an alpine grassland in the Qinghai Lake Basin.

Soil arthropods are important biological components of the soil food web, which are highly sensitive to environmental disturbances and can rapidly respond to changes in the external environment, then reflect the stability and health of the soil ecosystem. We investigated the community structure of soil arthropod and their responses to grazing intensity along soil depth (from topsoil to subsoil) through a manipulated grazing treatment with four intensity levels (no grazing, light grazing, moderate grazing and heavy grazing) in an alpine grassland in the Qinghai Lake basin. The results showed that: (1) Collembola was the dominant group in the experimental site. (2) Nearly two-thirds of the individuals were distributed in the topsoil (0-10 cm), and grazing did not cause soil arthropods to migrate from the topsoil to deeper soil layers. (3) Light grazing had a positive effect on increasing the individual number, family richness and diversity of soil arthropods, while heavy grazing had the opposite effect, exerting a negative impact on the soil arthropod community. (4) When the grazing intensity did not exceed moderate grazing (i.e. stocking rate of 3.86 Tibetan sheep·hm-2), grazing would have a positive effect on the soil arthropod community. In summary, light grazing is the intensity of disturbance that has a positive effect on the soil arthropod community in this region. This study not only revealed the impact of grazing on the community structure of soil arthropods but also aided in assessing the potential effects of grazing activities on the stability of soil ecosystems, providing scientific evidence for the sustainable management of alpine grasslands.

Effects of Fertilized Copper Sulfate on the Przewalski’s Gazelles of Molybdenosis in the Qinghai Lake Watershed

Effects of Fertilized Copper Sulfate on the Przewalski’s Gazelles of Molybdenosis in the Qinghai Lake Watershed

Molecular identification of tick (Acari: Ixodidae) and tick-borne pathogens from Przewalski's gazelle (Procapra przewalskii) and Tibetan sheep (Ovis aries) in Qinghai Lake National Nature Reserve, China

Molecular identification of tick (Acari: Ixodidae) and tick-borne pathogens from Przewalski's gazelle (Procapra przewalskii) and Tibetan sheep (Ovis aries) in Qinghai Lake National Nature Reserve, China

Determining the Fish Migration Patterns Based on Fish Habitat Assessment at a River Confluence

ABSTRACTMuch effort has been devoted to predicting fish migration routes to assist target species migration, and yet, fish migration science and practice remain imperfect. This study aimed to predict the migration paths of Gymnocypris przewalskii at the river confluence in the Qinghai Lake basin. The authors proposed an approach for fish migration route prediction, which involves a hydrodynamic module, a habitat model and a fish migration module. The TELEMAC‐MASCARET system was used to simulate hydrodynamic conditions and statistical analyses were carried out. During the flood season, G. przewalskii migrates downstream, whereas during the migratory season, they migrate upstream. The results indicate that flow velocity was the most significant hydrodynamic parameter affecting fish migration behaviour. The optimal flow velocity range for the target fish species was between 0.7 and 1.7 m/s. The impact of water depth was only observed in low discharge situations. Besides, the temperature plays a vital role in determining fish migration and abundance. However, the results reveal that in the morning hours, the temperature exhibits a range of 10°C to 16°C, and in the noon, the average temperature ranges from 16°C to 19°C, with a maximum temperature reaching 23°C. These temperature variations enable fish to migrate towards the tributary offering a more favourable water temperature during route selection at a river confluence. The study concludes that future research should consider incorporating the swimming capacity of the focal fish species to provide insights into fish migration patterns.

Changes in the Phylogenetic Structure of Alpine Grassland Plant Communities on the Qinghai-Tibetan Plateau with Long-Term Nitrogen Deposition.

Nitrogen (N) deposition rates have notably increased around the world, especially in high-altitude regions like the Qinghai-Tibetan Plateau (QTP). We conducted a six-year comprehensive experiment to simulate nitrogen deposition in an alpine grassland area near Qinghai Lake. Four levels of nitrogen depositions, i.e., 0 (CK), 8 kg N ha-1year-1 (N1), 40 kg N ha-1year-1 (N2), and 72 kg N ha-1year-1 (N3), with three replicates for each N treatment, were tested annually in early May and early July, with the meticulous collection of plant and soil samples during the peak growth period from 15 July to 15 August. We used the null model to evaluate the impact of environmental filtration and interspecific competition on the dynamics of the plant community was assessed based on the level of discrete species affinities within the plant community by constructing a phylogenetic tree. The results showed that the environmental filter was the predominant driver for the change of community's genealogical fabric. The N2 and N3 treatments increased the influence of soil factors on the change of plant community structure. Climatic factors played a crucial role on the change of plant community in the CK grassland area, while soil factors were dominant in the N1- and N3-treated grasslands.

First detection and biological characterization of an avian metaavulavirus 8 isolated from a migratory swan goose in Qinghai Lake, Northwest China.

Avian metaavulavirus 8 (AMAV-8), formerly known as avian paramyxovirus 8 (APMV-8), has been detected sporadically in wild birds worldwide since it was first identified in a Canadian goose in 1976. However, the presence of AMAV-8 in birds has never been reported in China. To understand the epidemiological situation of AMAV-8 and its ability to infect chickens, we conducted a surveillance study and in vivo analysis of the AMAV-8 isolate identified in total of 14,909 clinical samples collected from wild and domestic birds from 2014 to 2022 in China. However, in 2017, only one AMAV-8 virus (Y7) was successful isolated from the fresh droppings of a migratory swan goose in Qinghai Lake in Northwest China. Thereafter, we report the complete genome sequence of the Y7 strain with a genome length of 15,342 nucleotides and the Y7 isolate was genetically closely-related to wild bird-origin AMAV-8 viruses previously circulated in the United States, Japan, and Kazakhstan. Furthermore, AMAV-8 infections of one-day-old specific pathogen-free (SPF) chicks did not induce any clinical signs over the entire observation period but was associated with viral shedding for up to 8 days. Interestingly, although all birds infected with the Y7 strain seroconverted within the first week of infection, virus replication was only detected in the trachea but not in other tissues such as the brain, lung, or heart. Here, we report the complete genome, genetic and biological characterization, replication and pathogenicity analysis in vivo and first detection of AMAV-8 in China.

Highly Pathogenic Avian Influenza A Virus in Wild Migratory Birds, Qinghai Lake, China, 2022.

In July 2022, an outbreak of highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b occurred among migratory birds at Qinghai Lake in China. The virus circulated in June, and reassortants emerged after its introduction into the area. Surveillance in 2023 showed that the virus did not establish a stable presence in wild waterfowl.

Lithium isotope systematics in an endorheic saline lacustrine system: Insights from Qinghai Lake, China

The study of lithium isotopic (δ7Li) signatures in sedimentary deposits has become a powerful tool to infer past silicate weathering regimes, thus informing our knowledge of the geological carbon cycle and paleoclimate evolution. Sediments from Qinghai Lake, the largest saltwater lake in China (4625 km2), offer an unparalleled archive for investigating the climatic history of the Qinghai-Tibet Plateau. However, prior to leveraging the δ7Li proxy in this context, it is imperative to unravel the mechanisms of lithium (Li) isotope fractionation and elemental cycling within the lake's aqueous and sedimentary systems. In this study, we collected and analyzed samples of Qinghai Lake's water, sediments, and recharge waters (rivers, groundwater, and rainfall) to investigate the processes controlling the δ7Li value recorded in Qinghai Lake sediments.Our data reveal subtle variances in Qinghai Lake water Li concentration ([Li]), ranging from 652 to 873 ng/g, suggesting interactions with iron oxides or suspended matter. The δ7Li signature, however, exhibits remarkable uniformity across the lake at 32.1‰ (±0.4‰). Near the estuary of the Buha River, there is a swift homogenization of [Li] and δ7Li, stabilizing within just 3 km of the inflow. Lake sediments exhibit δ7Li values ranging from 1.5‰ to 6.6‰, exceeding those of the upper continental crust (∼0‰ ± 4‰), yet approximately 30‰ lower than those in lake waters. This significant discrepancy between the δ7Li of lake water and sediments is likely due to the preferential incorporation of 6Li over 7Li during the neoformation of clay minerals.Lithium mass balance modeling for Qinghai Lake, incorporating inputs from river and groundwater (∼46.5 t/a with δ7Li ∼18.3‰) and outputs via clay mineral uptake (∼44 t/a with δ7Li ∼5.1‰), indicates that the lake's Li system is currently out of steady state. The model predicts a gradual rise in the lake's Li inventory, estimated to achieve steady state within 1.2 ka and the δ7Li value of lake water will increase until reaching ∼45‰ assuming constant climate conditions.

Novel genomic and phenotypic traits of polyhydroxyalkanoate-producing bacterium ZZQ-149, the type strain of Halomonas qinghailakensis

BackgroundPolyhydroxyalkanoates (PHAs) are optimal potential materials for industrial and medical uses, characterized by exceptional sustainability, biodegradability, and biocompatibility. These are primarily from various bacteria and archaea. Bacterial strains with effective PHA formation capabilities and minimal production cost form the foundation for PHA production. Detailed genomic analysis of these PHA-generating bacteria is vital to understand their PHA production pathways and enhance their synthesis capability.ResultsZZQ-149, a halophilic, PHA-producing bacterium, was isolated from the sediment of China’s Qinghai Lake. Here, we decoded the full genome of ZZQ-149 using Single Molecule Real Time (SMRT) technology based on PacBio RS II platform, coupled with Illumina sequencing platforms. Physiological, chemotaxonomic traits, and phylogenetic analysis based on 16 S rRNA gene and single copy core genes of ninety-nine Halomonas type strains identified ZZQ-149 as the type strain of Halomonas qinghailakensis. Furthermore, a low average nucleotide identity (ANI, < 95%) delineated the genetic differences between ZZQ-149 and other Halomonas species. The ZZQ-149 genome, with a DNA G + C content of 52%, comprises a chromosome (3, 798, 069 bps) and a plasmid (6, 107 bps). The latter encodes the toxin-antitoxin system, BrnT/BrnA. Through comprehensive genome sequencing and analysis, we identified multiple PHA-synthesizing enzymes and an unprecedented combination of eight PHA-synthesizing pathways in ZZQ-149.ConclusionsBeing a halophilic, PHA-producing bacterium, ZZQ-149 exhibits potential as a high PHA producer for engineered bacteria via genome editing while ensuring low-cost PHA production through continuous, unsterilized fermentation.

Identification and characterization of multiple novel viruses in fecal samples of ruddy shelducks using viral metagenomics methods

The viral metagenomics approach is an effective technique for investigating and analysing both existing and emerging viruses in humans and diverse animal samples. The ruddy shelduck, a nationally protected secondary key species of wild animals, has become the predominant species among overwintering waterbirds in Qinghai Lake. Viruses carried by ruddy shelducks can potentially infect humans or other animals; however, limited research on the faecal virome of ruddy shelducks is currently available. In the present study, faecal samples of ruddy shelducks collected from Saga County, Shigatse City, Tibet, China, were subjected to viral metagenomic analysis. The predominant viral families identified in ruddy shelduck samples were Picornaviridae, Parvoviridae, Microviridae, Vilyaviridae, Astroviridae, and Caliciviridae. Among these, two picornavirus genomes have been identified as new strains of the genus Megrivirus in the family Parvoviridae. In addition, viruses that infect parasites and bacteria have been identified and characterised. The present study enhances our comprehension of the composition of the viral community in ruddy shelducks faeces and highlights the dynamic nature of viral evolution and the significance of continuous monitoring to assess potential risks to wildlife and public health.

Soil Genesis of Alluvial Parent Material in the Qinghai Lake Basin (NE Qinghai–Tibet Plateau) Revealed Using Optically Stimulated Luminescence Dating

Alluvial parent material soil is an important soil type found on the Qinghai–Tibet Plateau (QTP) in China. However, due to the limited age data for alluvial soils, the relationship between alluvial geomorphological processes and soil pedogenic processes remains unclear. In this study, three representative alluvial parent material profiles on the Buha River alluvial plain in the Qinghai Lake Basin, northeast QTP, were analyzed using the optical luminescence (OSL) dating method. Combined with physical and chemical analyses of the soil, we further analyzed the pedogenic process of alluvial soil. The alluvial parent material of the Buha alluvial plain predominately yielded ages between 11.9 and 9.1 ka, indicating that the alluvial soil began to form during the early Holocene. The development of the alluvial soil on the first-order terrace presents characteristics of entisol with multiple burial episodes, mainly between 8.5 and 4.0 ka, responding to the warm and humid middle Holocene and high lake levels.

Lake Surface Temperature Predictions under Different Climate Scenarios with Machine Learning Methods: A Case Study of Qinghai Lake and Hulun Lake, China

Lake Surface Temperature Predictions under Different Climate Scenarios with Machine Learning Methods: A Case Study of Qinghai Lake and Hulun Lake, China

Evaluation of pool-and-weir fishway efficiency for the upstream spawning migration of Qinghai Lake's naked carp

Przewalski's Naked Carp (Gymnocypris przewalskii) is a typical migratory fish species of the Qinghai Lake region (China). This study focused on the Gangbei Channel fishway located in the Shaliu River, a tributary of Qinghai Lake. A fish passage study was conducted during the peak of the upstream migration of G. przewalskii, and entry proportion and passage efficiency in the Gangbei channel fishway was monitored in real-time using PIT-Telemetry. A detailed hydraulic characterization of the fishway was done using a 3-D numerical model validated by in-situ measurements, and combined with empirical swimming ability data for the species. The results showed that: (1) the proportion of released G. przewalskii entering and passing the fishway were 13% and 5%, respectively; (2) discharge, fish body length, salinity, and diel period were key factors affecting the attempt rate of the G. przewalskii; (3) The critical swimming speed and sprint swimming speed at 50% of G. przewalskii reaching fatigue were 1.02 m/s and 1.91 m/s, respectively; (4) Based on the swimming ability of G. przewalskii and the hydraulic characteristics of the fishway, the flow velocity at the weir sections of the fishway exceeded the sprint swimming ability of G. przewalskii, creating a velocity barrier. Data derived from this study will be used to provide a more comprehensive theoretical basis and data reference for the eco-hydraulic reconstruction of pool-and-weir fishways providing an efficient upstream passage for the conservation of G. przewalskii and other species.

Measuring and reducing the ecological risk of community tourism for ecosystem conservation

The escalating ecological risks associated with Community Tourism (CT) pose a significant threat to ecosystem conservation worldwide, yet methods to predict and prevent CT-induced problems remain underexplored. In the context of the pronounced emphasis on the economic advantages of CT and its extensive implementation, the spatial prediction of CT-induced ecological issues and the corresponding effective preventative strategies are crucial. This study integrates composite indicators, Public Participation Geographic Information Systems, spatial statistics, and scenario analysis to develop Community Tourism Ecological Risk Models (CTERMs). Using the Qinghai Lake region as a case study, this study quantifies the spatial distribution of ecological risks associated with CT, identify priority areas for intervention, and propose enhanced mitigation strategies. Results indicate that CTERMs effectively pinpoint sites of ecological concern, making them valuable tools for forecasting CT-induced problems. Although high-risk areas constitute a small portion of the study area, significant disparities among communities highlight three clusters requiring urgent preventive measures. The current tourism concession layout is inadequate for mitigating CT-induced ecological risks. Adjusting the locations of concessions, while maintaining their current number, can significantly reduce ecological threats and protect endangered species. These findings demonstrate that strategic concession placement offers considerable ecological benefits. As new frameworks for biodiversity conservation are being considered, conservation scientists and policymakers are presented with an opportunity to integrate community development, poverty reduction, and ecosystem conservation by utilizing CTERMs for the strategic allocation of concessions.

Five-year longitudinal surveillance reveals the continual circulation of both alpha- and beta-coronaviruses in Plateau and Gansu pikas (Ochotona spp.) at Qinghai Lake, China1

ABSTRACT The discovery of alphacoronaviruses and betacoronaviruses in plateau pikas (Ochotona curzoniae) expanded the host range of mammalian coronavirus (CoV) to a new order – Lagomorpha. However, the diversity and evolutionary relationships of CoVs in these plateau-region-specific animal population remains uncertain. We conducted a five-year longitudinal surveillance of CoVs harboured by pikas around Qinghai Lake, China. CoVs were identified in 33 of 236 plateau pikas and 2 of 6 Gansu pikas (Ochotona cansus), with a total positivity rate of 14.5%, and exhibiting a wide spatiotemporal distribution across seven sampling sites and six time points. Through meta-transcriptomic sequencing and RT–PCR, we recovered 16 near-complete viral genome sequences. Phylogenetic analyses classified the viruses as variants of either pika alphacoronaviruses or betacoronaviruses endemic to plateau pikas from the Qinghai-Tibet Plateau region. Of particular note, the pika-associated betacoronaviruses may represent a novel subgenus within the genus Betacoronavirus. Tissue tropism, evaluated using quantitative real-time PCR, revealed the presence of CoV in the rectal and/or lung tissues, with the highest viral loads at 103.55 or 102.80 RNA copies/μL. Surface plasmon resonance (SPR) assays indicated that the newly identified betacoronavirus did not bind to human or pika Angiotensin-converting enzyme 2 (ACE2) or Dipeptidyl peptidase 4 (DPP4). The findings highlight the ongoing circulation and broadening host spectrum of CoVs among pikas, emphasizing the necessity for further investigation to evaluate their potential public health risks.

Evaluating evaporites as potential archives of lake and seawater lithium isotopic ratios: An experimental study using various natural saline fluids

Reconstructing the lithium isotope composition (δ7Li) of ancient seawater and lacustrine environment is crucial for tracing silicate weathering processes that regulate Earth's carbon cycle and climate. This study examines the reliability of evaporite minerals in preserving the Li isotope signature of the original brines from which they precipitate. We conducted evaporation experiments on modern natural waters from Qinghai Lake, the Yellow Sea, and Chaka Salt Lake, each with unique salinity and chemical composition, to examine the behavior of lithium isotope ratios in the evolving brine and precipitated evaporite minerals.Our results show that initial hydrochemical conditions of the lake and ocean are the primary control on the evolution of major and trace elements and the mineral precipitation sequences during evaporative concentration. Aragonite, calcite, gypsum, and/or nesquehonite precipitated prior to halite. Li isotope fractionation of these non-halite precipitates varied significantly between 4‰ and 17‰. However, the δ7Li values of halite closely mirror those of the initial lake and seawater, indicating negligible Li isotope fractionation (<1‰) during halite precipitation. The δ7Li values of the evolving brines remain unchanged throughout the evaporation experiment. Solid phases precipitating before halite constitute <1–2% of the total moles of salt precipitated from the complete evaporation of the initial waters, thus, having little to no influence on the δ7Li values of evolving brines. Although halite comprises >77% of the total moles of salt, it does not fractionate Li isotopes. Therefore, halite more accurately reflects the δ7Li values of the co-evolving brine as well as those of the initial, unevaporated lake and seawater. These results underscore the potential of late stage evaporites, particularly halite, to serve as high-fidelity archives of ancient lacustrine and seawater δ7Li values. Such records are instrumental in reconstructing past silicate weathering and climatic conditions.

Response Characteristics and Community Assembly Mechanisms of nirS-Type Denitrifiers in the Alpine Wetland under Simulated Precipitation Conditions.

The nitrogen cycling process in alpine wetlands is profoundly affected by precipitation changes, yet the dynamic response mechanism of denitrifiers to long-term precipitation shifts in the alpine wetland of the Qinghai-Tibet Plateau remains enigmatic. Utilizing high-throughput sequencing analysis of nirS-type functional genes, this study delved into the dynamic response mechanism of nirS-type denitrifiers to precipitation changes in the alpine wetland of Qinghai Lake. The findings revealed that nirS-type denitrifiers in the alpine wetland of Qinghai Lake were primarily Proteobacteria, and Alpha diversity exhibited a negative correlation with the precipitation gradient, with deterministic processes predominating in the community assembly of denitrifying microbes. A 50% increase in rainfall shifted the community assembly process of denitrifiers from deterministic to stochastic. Dominant microflora at the genus level responded significantly to precipitation changes, with aerobic bacteria comprising the majority of differentially abundant taxa (55.56%). As precipitation increased, the complexity of the microbial interaction network decreased, and a 25% reduction in precipitation notably elevated the relative abundance of three key functional groups: chemoheterotrophic, aerobic chemoheterotrophic, and nitrogen fixation. Precipitation notably emerged as the primary regulator of nirS-type denitrifiers in the alpine wetland of Qinghai Lake, accounting for 51% of the variation in community composition. In summary, this study offers a fresh perspective for investigating the ecological processes of nitrogen cycling in alpine ecosystems by examining the diversity and community composition of nirS-type denitrifiers in response to precipitation changes.

Study of the patterns of variations in ice lakes and the factors influencing these changes on the southeastern Tibetan plateau

The ice lakes in the southeastern Qinghai–Tibet Plateau have exhibited a pronounced expansion against the backdrop of global warming, consequently amplifying the local risk of ice lake outburst disasters. However, surveys of ice lake changes in the entire region have consistently been incomplete due to the prevalent high cloud density. On the basis of Landsat remote sensing images and the Google Earth Engine (GEE) cloud computing platform, in this study, the full convolution segmentation algorithm is utilized to accurately and comprehensively map the regional distribution of ice lakes in southeastern Tibet at consistent time intervals in 1993, 2008, and 2023. Furthermore, the formation, distribution, and dynamic changes in these ice lakes are investigated. The numbers of ice lakes discovered in 1993, 2008, and 2023 were 2520, 3198, and 3877, respectively. These lakes covered areas of approximately 337.64 ± 36.86 km2, 363.92 ± 40.90 km2, and 395.74 ± 22.72 km2, respectively. These ice lakes are located primarily between altitudes of 4442 m and 4909 m. The total area experienced an annual growth rate of approximately 0.57 % from 1993 to 2023. In the present study, the long-term variations in ice lakes in each district and county are examined. These findings indicate that between 1993 and 2023, the expansion of ice lakes was more pronounced in regions with a large number of marine glaciers. Notably, Basu County presented the highest annual growth rate of the ice lake population, at 6.23 %, followed by Bomi County, at 4.28 %, and finally, Zayul County, at 2.94 %. The accelerated shrinkage of marine glaciers induced by global warming is the primary driver behind the expansion of ice lakes. The results obtained from this research will enhance our overall understanding of the complex dynamics and mechanisms that govern the formation of ice lakes while also offering valuable perspectives on the potential risks linked to their expansion in this particular area.

Copper Sulfate Supplementation Alleviates Molybdenosis in the Tibetan Gazelles in the Qinghai Lake Basin.

Molybdenum (Mo), an essential mineral, plays a key role in the vital activity of the organism. However, excess Mo in the forage will cause loss of appetite, diarrhea, emaciation, bone injury, joint abnormalities, and anemia in animals. In order to study molybdenosis in the Procapra picticaudata in the animal rescue center, samples of soils, forages, blood, and liver were collected. The mineral contents of all samples were determined, and the blood parameters were also measured. The results showed that the Mo level in the soil and forage in the animal rescue center was significantly higher than that in healthy pastures (p < 0.01). The Mo concentrations in the blood and liver in the P. picticaudata from the animal rescue center were also noticeably higher than those in healthy animals (p < 0.01). The level of Cu in the blood and liver were noticeably lower than those in healthy P. picticaudata (p < 0.01). The superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), and catalase (CAT) were significantly lower than those in healthy animals. Supplementing copper sulfate (CuSO4) could significantly decrease the Mo content in the blood, and cure molybdenosis. In summary, the excessive Mo content in the soil and forage in the animal rescue center had greatly affected physiological parameters and antioxidant capacity. It is likely that the molybdenosis of the P. picticaudata is caused by the high Mo contents in soils and forages. CuSO4 may alleviate molybdenosis in P. picticaudata.

Adequate water supply enhances seedling growth and metabolism in Festuca kryloviana: insights from physiological and transcriptomic analys

BackgroundFestuca kryloviana is a significant native grass species in the Qinghai Lake region, and its low emergence rate is a primary factor limiting the successful establishment of cultivated grasslands. The region’s arid and low-rainfall climate characteristics result in reduced soil moisture content at the surface. Despite the recognized impact of water availability on plant growth, the specific role of moisture in seedling development remains not fully elucidated. This study aims to investigate the germination rate and seedling growth velocity of F. kryloviana seeds under varying moisture conditions, and to integrate physiological and transcriptomic analyses of seedlings under these conditions to reveal the mechanisms by which water influences seedling development.ResultsThe emergence rate of F. kryloviana seedlings exhibited an initial increase followed by a decrease with increasing moisture content. The highest emergence rate, reaching 75%, was observed under 20% soil moisture conditions. By the eighth day of the experiment, the lengths of the plumules and radicles under the optimal emergence rate (full water, FW) were 21.82% and 10.87% longer, respectively, than those under closely matching the soil moisture content during the background survey (stress water, SW). The differential development of seedlings under varying moisture regimes is attributed to sugar metabolism within the seeds and the accumulation of abscisic acid (ABA). At FW conditions, enhanced sugar metabolism, which generates more energy for seedling development, is facilitated by higher activities of α-amylase, sucrose synthase, and trehalose-6-phosphate synthase compared to SW conditions. This is reflected at the transcriptomic level with upregulated expression of the α-amylase (AMY2) gene and trehalose-6-phosphate synthase (TPS6), while genes associated with ABA signaling and transduction are downregulated. Additionally, under FW conditions, the expression of genes related to the chloroplast thylakoid photosystems, such as photosystem II (PSII) and photosystem I (PSI), is upregulated, enhancing the seedlings’ light-capturing ability and photosynthetic efficiency, thereby improving their autotrophic capacity. Furthermore, FW treatment enhances the expression of the non-enzymatic antioxidant system, promoting metabolism within the seeds. In contrast, SW treatment increases the activity of the enzymatic antioxidant system, including peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), to cope with water stress.ConclusionsOur experiment systematically evaluated the impact of moisture conditions on the growth and development of F. kryloviana seedlings. Physiological and transcriptomic data collectively indicate that adequate water (20%) supply enhances seedling growth and development by reducing ABA levels and increasing α-amylase activity within seeds, thereby boosting sugar metabolism and promoting the growth of seedling, which in turn leads to an improved emergence rate. Considering water management in future cultivation practices may be a crucial strategy for enhancing the successful establishment of F. kryloviana in grassland ecosystems.