Nutrient enrichment is a key driver of plant diversity loss in grassland ecosystems. However， the specific pathways and mechanisms underlying species diversity reduction under different nutrient additions influence remain insufficiently understood. This study investigated the effects of nitrogen （N）， phosphorus （P）， and combined nitrogen and phosphorus （N+P） additions on alpine meadows located on the eastern edge of the Tibetan Plateau， using the natural community as a control. The main objective was to examine changes in species richness， biomass， and light transmission， and to elucidate the direct and indirect mechanisms contributing to species richness decline under these experimental treatments. The results showed as follows：（1） N was identified as the primary limiting nutrient for aboveground biomass. Both N and N+P additions significantly increased aboveground biomass （P<0.05）， primarily due to an increase in the biomass of grasses； （2） N and N+P additions significantly reduced species richness （P<0.05）， whereas P addition alone had no significant effect； （3） The mechanisms underlying the reduction in species richness under N and N+P treatments were consistent and involved both direct effects of nitrogen and indirect effects via increased aboveground biomass， which in turn reduced light availability.

To investigate salt tolerance in alfalfa （Medicago sativa） germplasm， 30 alfalfa accessions of diverse origins were subjected to salt stress （200 mmol/L NaCl） for 15 days. Responses were evaluated through changes in seedling morphology， photosynthetic parameters， and physiological indices compared to control plants （CK， irrigated with Hoagland nutrient solution）. The results demonstrated that NaCl treatment decreased plant height， leaf area， leaf relative water content， root activity， shoot dry weight， chlorophyll a， chlorophyll b， transpiration rate， stomatal conductance， net photosynthetic rate， intercellular CO₂ concentration， water use efficiency， catalase （CAT） activity， and potassium （K⁺） content relative to CK. Conversely， root dry weight， root-to-shoot ratio， stomatal limitation value， proline content， malondialdehyde （MDA） content， peroxidase （POD） activity， superoxide dismutase （SOD）， sodium （Na⁺） content， and the Na⁺/K⁺ ratio exhibited increases. Regression analysis identified stomatal conductance， root activity， root-to-shoot ratio， and Na⁺ content as critical indicators for salt tolerance evaluation. The clustering analysis based on the comprehensive evaluation value of the membership function shows that the 30 alfalfa accessions were classified into four distinct tolerance categories： high salt-tolerant， moderately salt-tolerant， low salt-tolerant， and salt-sensitive. Accessions 7254 and 7657 exhibited high salt tolerance.

Dof （DNA-binding with one finger） transcription factors are plant-specific regulators playing critical roles in plant response to environmental stresses. This study comprehensively identified MrDof gene family based on the genome-wide of Medicago ruthenica. We performed analyses including collinearity assessment， phylogenetic analysis， and chromosomal localization on the Dof family members. Furthermore， by integrating transcriptome data of M. ruthenica under drought stress and qRT-PCR validation， we explored the potential functions of these genes in drought stress responses. The results showed that a total of 33 MrDof genes were identified in M. ruthenica， and the number of amino acids encoded by these genes ranged from 157 to 492 aa. According to the evolutionary relationships among M. ruthenica， Medicago truncatula and Arabidopsis thaliana， these genes were classified into eight distinct groups （Group A， B1， B2， C1， C2.1， C2.2， C3， D1 and D2）. The 33 genes were unevenly distributed across nine chromosomes. Expression pattern analysis demonstrated that five genes （MrDof11， MrDof13， MrDof22， MrDof27， and MrDof30） were significantly induced by drought stress.

In this study， alfalfa （Medicago sativa cv. Zhongmu No.1） was used as experimental material under mixed saline-alkali stress at concentrations of 0， 40， and 80 mmol/L （NaCl， Na2SO4， Na2CO3 and NaHCO3 molar ratios of 1∶1∶1∶1， pH 9.3）. The growth indexes， physiological indexes and the expression levels of key genes of the seedlings were measured， which provided a theoretical basis for revealing the mechanism of response to mixed saline-alkali stress. The results showed that the plant height， photosynthetic rate， effective quantum yield of PSⅡ photochemistry and the maximum quantum efficiency of PSⅡ photochemistry （Fv/Fm） in ‘Zhongmu No.1’ alfalfa seedlings were significantly inhibited with the intensification of mixed saline-alkali stress （P<0.05）. The accumulation of hydrogen peroxide， superoxide anion， and malondialdehyde gradually increased， while the activity of peroxidase， proline， and soluble sugar content all significantly increased （P<0.05）. Under 80 mmol/L mixed saline-alkali stress， the expression levels of Na+ transporter encoding genes MsSOS1， MsNHX1， and MsHKT1 were significantly induced （P<0.05）. In summary， ‘Zhongmu No.1’ alfalfa may mainly respond to mixed saline-alkali stress through the following pathways： （1） high expression of Na+ transporter genes such as MsSOS1， MsNHX1， and MsHKT1， promoting Na+ efflux， vacuolar segregation and transfer， and avoiding ion toxicity to plants caused by excessive accumulation of Na+； （2） enhance antioxidase activity and alleviate oxidative damage caused by high pH value.

This study focused on Poacceae weeds Digitaria sanguinalis and broad-leaved weeds Amaranthus retroflexus， which pose a serious threat to alfalfa fields. The allelopathic effects of six phenolic acids on seed germination （germination percentage， germination potential， germination index） and seedling growth （height and fresh weight） of the two weeds were determined to develop bioherbicides for alfalfa fields. The results indicated that： The allelopathic effects on the seed germination and seedling growth of Digitaria sanguinalis and Amaranthus retroflexus varied after treated with six phenolic acids. The phenolic acids with high concentration inhibited the seed germination and seedling growth of the two weeds， while some of the low-concentration phenolic acids showed “low-concentration promotion and high-concentration inhibition” on the seedling growth of Digitaria sanguinalis. When the concentration of the solution is 500 mg/L， the order of the allelopathic effects on Digitaria sanguinalis was： coumarin=salicylic acid>caffeic acid>ferulic acid>p-hydroxybenzoic acid>chlorogenic acid； and the order of the allelopathic effects on Amaranthus retroflexus was： coumarin=salicylic acid>ferulic acid>p-hydroxybenzoic acid>chlorogenic acid>caffeic acid. Except for caffeic acid， the inhibition of chlorogenic acid， ferulic acid， p-hydroxybenzoic acid， coumarin， and salicylic acid with the same concentration on Amaranthus retroflexus was stronger than that of Digitaria sanguinalis. The effects of the same phenolic acid varied significantly on different growth stages （germination and early growth of seedlings） of the same weed. High concentration phenolic acid Seedling growth was inhibited more compared to seed germination by high concentration phenolic acid.

In the context of global climate change， the impact of extreme climate on grassland productivity has attracted extensive attention of academics and research institutions worldwide. In order to investigate hotspots in this research field and assess the state of current international research frontiers， this article exported literature data from the core database of Web of Science， and visualized with CiteSpace to analyze and summarize the status of international research on the impact of extreme climate on grassland productivity. The results demonstrated an increasing trend in research publications from 1992 to 2023 regarding the impact of extreme climate on grassland productivity， especially a rapid increase from 2019 to 2023. Collaborative teams were assembled by authors， though connections between different teams were not solid as expect. Scholars from both China and the United States have published over 200 academic papers， which leading the field of effects of extreme climate on grassland productivity. Over the past two years， Lanzhou University， Chinese Academy of Agricultural Sciences have played crucial roles in the research of effects of extreme climate on grassland productivity. A comprehensive analysis of hotspots and frontiers reveals that research in recent three years primarily focused on the impact of extreme drought on grassland productivity， as well as the legacy effects of extreme climate on grassland. Future research on grassland extreme climate should pay more attention on a thorough analysis of complex extreme climate， and elucidate the role of biodiversity and biological interactions in regulating ecosystem for the response to extreme climate events.

Shrub encroachment， which significantly alters structure and function of grassland ecosystems， is a critical ecological issue in China. To obtain a comprehensive and quantitative understanding of the research trends on shrub encroachment research in China， this study conducted a bibliometric analysis using CiteSpace and a meta-analysis based on published literatures on shrub encroachment in China since 1970s. Research on shrub encroachment in China had developed rapidly in recent years， with a primary focus on the drivers of shrub encroachment and its impacts on soil， vegetation， and biodiversity. Studies on shrub encroachment in China had been predominantly conducted in drylands and alpine regions. Major drivers of shrub encroachment included grazing management， climate change， habitat characteristics， and fire. Shrub encroachment was found to have a negative impact on soil quality but a positive effect on community composition， as well as the structure of vegetation and microbial communities in China. The primary management techniques for shrub encroachment included grazing exclusion， grazing management， physical removal， and prescribed burning. This study provides scientific insight into the drivers， impact， and future management strategies for shrub encroachment in Chinese grassland. In the future， it is necessary to strengthen large-scale dynamic assessments of shrub encroachment across diverse grassland types， and integrate remote sensing technology to enhance the scientificity and effectiveness of monitoring and management of encroached landscape in China.

To investigate the mitigation effect of externally applied γ-aminobutyric acid （GABA） on the growth of alfalfa seedlings under drought stress， this study explored five new drought-resistant alfalfa lines （P1， P2， P3， P4， and P5） and five drought-sensitive materials （15354， 7657， 7470， 7740， and 15578）. With normal water supply as the control （CK）， drought stress was simulated using the previously screened stress intensity （-1.6 MPa PEG-6000）. Under this drought stress treatment， exogenous GABA was applied at concentrations of 0， 5， 10， and 15 mmol/L （designated as T1， T2， T3， and T4， respectively） to analyze their effects on the physiological characteristics of alfalfa seedlings. Results showed that external GABA application significantly increased superoxide dismutase， peroxidase， catalase， leaf relative water content， and root activity in alfalfa under drought stress， while the content of proline， soluble sugar， soluble protein， malondialdehyde， hydrogen peroxide， and the production rate of superoxide anion were decreased. Membership function analysis revealed the optimal alleviation of GABA on drought-stressed alfalfa under the T3 treatment， with significantly stronger mitigation effect on sensitive genotypes compared with drought-resistant lines. The results provide a theoretical basis for the rational application of GABA in drought-tolerant cultivation of alfalfa.

To investigate the effects of plateau zokor （Eospalax baileyi） disturbance on soil stoichiometry and plant diversity，as well as changes in their interrelationships，this study established three disturbance intensities （light，moderate，and heavy），using undisturbed grassland （without zokor mounds） as the control. We assessed plant species richness and abundance，Shannon-Wiener and Simpson’s diversity indices，and evenness，alongside measurements of soil organic carbon （SOC），total nitrogen （TN），and total phosphorus （TP） contents. Differences and variation patterns in plant diversity and soil stoichiometric traits across disturbance levels were analyzed to determine whether plateau zokor disturbance alters the relationship between soil stoichiometry and plant diversity. The results showed as follows： （1） Under heavy disturbance，SOC and TN contents were significantly lower than those at other disturbance intensities，while TP content was significantly lower under light disturbance compared to other treatments （P<0.05）. （2） The soil C∶P ratio under light disturbance was significantly higher than in all other treatments （P<0.01）. Similarly，the soil N∶P ratio was significantly higher than in both the control and heavy disturbance treatments （P<0.01）. However，no significant difference was observed in the soil C∶N ratio across treatments. （3） Plant species richness，Shannon-Wiener and Simpson’s diversity indices，and evenness all exhibited an upward trend with increasing disturbance intensity，being significantly higher than in the control （P<0.05）. （4） In the undisturbed area，species richness was positive correlated with soil C∶N and N∶P ratios；however，these relationships were not observed under zokor disturbance. Under heavy disturbance，the relationships between species diversity indices and soil N∶P and C∶P ratios were significantly affected，with positive correlation between evenness and the N∶P ratio becoming stronger. In conclusion，plateau zokor disturbance significantly influenced SOC，TP，and TN contents，promoted higher plant species diversity，and modified the relationships between plant diversity and soil stoichiometric characteristics.

This study investigated the effects of exogenous 2， 4-epibrassinolide （EBR） on seed germination and seedling physiological characteristics of Prunella vulgaris under drought stress， to provide a theoretical basis for its efficient cultivation in arid regions. Seeds of P. vulgaris were soaked with EBR solutions at different concentrations （0， 0.01， 0.05， 0.10， and 0.20 μmol/L）， and then germinated under drought simulation by 20% polyethylene glycol （PEG-6000） to investigate effects of EBR on seed germination. The results indicated that drought stress significantly inhibited seed germination and seedling growth of P.vulgaris. Meanwhile， antioxidant enzyme activities and the content of osmotic regulatory substances were increased by drought stress， with electrolyte leakage in seedlings and a decrease in photosynthetic pigment content. After the treatment with 0.01-0.20 μmol/L EBR， seed germination and seedling growth under drought stress were improved. EBR treatment further enhanced antioxidant enzyme activities， soluble protein content， and soluble sugar content in seedlings， while reducing relative electrical conductivity， and promoting photosynthetic pigment accumulation. When the EBR soaking concentration increased from 0.01 to 0.20 μmol/L， the alleviation effect initially intensified and then declined. The comprehensive evaluation revealed that the effects of different concentrations of EBR on the seed germination and seedling growth of Prunella vulgaris under drought stress are followed the order of 0.10 μmol/L treatment>0.05 μmol/L treatment>0.01 μmol/L treatment>0.20 μmol/L treatment， with the 0.10 μmol/L treatment being the most effective.

This research aims to investigate the effects of different radiation doses of ⁶⁰Co-γ ray on seed germination and seedling establishment of timothy （Phleum pratense）， and to determine the optimal mutagen dose. Timothy seeds were exposed to different doses of ⁶⁰Co-γ radiation （100， 150， 200， 250， 300， 350， and 400 Gy） and non-irradiated seeds were served as the control. The results showed that all radiation doses decreased germination percentage， germination energy， and germination index. Radicle and plumule lengths decreased with the increasing radiation doses， except that plumule lengths increased at 100， 150， and 200 Gy and 100 Gy increased radicle length. Aboveground morphology parameters （plant height， leaf width， and tiller number）， root development parameters （total root length， root surface area， root volume， and root average diameter）， and chlorophyll content in timothy seedlings all exhibited an trend of initial increase followed by a decline. Linear regression analysis， determined the semi-lethal dose （LD₅₀） of ⁶⁰Co-γ radiation for dry timothy seeds was to be 204.2 Gy.

To investigate the effect of biochar coating on the drought resistance of Astragalus adsurgens， this experiment established four sand bed moisture levels （2%， 3%， 5%， and 10%， with 10% as control） and four biochar coating mass ratios （biochar∶seed at 1∶15， 1∶10， 1∶5， and 1∶3）. Germination tests conducted in the sand beds were aimed to identify apporiate drought stress simulation conditions and to determine the optimal biochar coating formulation. Effects of biochar coating on seedling emergence， seedling growth， and antioxidant enzyme activities under drought stress were also assessed. The results indicated showed that， under 2% sand bed moisture condition， which simulated drought conditions， the biochar coating treatment with at a 1∶10 mass ratio （biochar∶seed， denoted as BC1-10） significantly increased （P<0.05） seedling emergence rate， fresh weight， root length， seedling length， and antioxidant enzyme activities.

Nitrogen deposition represents a critical driver of nitrous oxide （N₂O） emissions in global terrestrial ecosystems， with profound implications for climate change prediction. Although numerous studies have investigated soil N₂O emissions patterns in response to nitrogen addition， controversies persist regarding the regulatory mechanisms and driving factors. Through a meta-analysis intergrading the 87 global studies， we demonstrate that nitrogen addition significantly enhances soil N₂O emissions. This effect is particularly pronounced under high nitrogen application rate （>200 kg/hm² year）， in low-precipitation regions （≤400 mm annual rainfall）， and with short-term and moderate-term nitrogen application （≤3 years）. Our analysis identified nitrogen input level， mean annual precipitation， and ecosystem type as the dominant factors controlling global N₂O emissions， providing a scientific foundation for developing targeted emission mitigation strategies.

This study investigated the effects of various fertilization treatments on natural mowing grassland in the Altay Mountains， combining field investigations with indoor laboratory analyses. The experiment included four fertilization measures：no fertilization （control）， compound fertilizer， organic fertilizer and bio-bacterial fertilizer. The primary objective was to assess these treatments on grassland plant community characteristics， soil nutrients， and soil microorganisms. The results showed as follows：（1） Compound fertilizer application significantly increased aboveground biomass （P<0.05）， but decreased underground biomass in the 0~10 cm soil layer. Bio-bacterial and organic fertilizers increased species diversity， while compound fertilizer reduced it. Notably， the Shannon-Wiener index was significantly higher under bio-bacterial fertilizer than under compound fertilizer （P<0.05）； （2） Fertilization significantly lowered soil pH and increased soil organic matter content. Organic fertilizer significantly increased available nitrogen content （P<0.05）， while compound fertilizer significantly raised available phosphorus and available potassium concentrations （P<0.05）； （3） Fertilization significantly increased the number of bacterial operational taxonomic units （OTUs） and decreased fungal OTUs （P<0.05）， indicating shifts in microbial community structure and enhanced microbial diversity. A comprehensive evaluation using a membership function approach indicated that compound fertilizer had the most substantial effect in improving degraded natural meadows. These findings provide a scientific basis for enhancing the productivity and soil fertility of natural meadows through appropriate fertilization strategies.

To evaluate the differences in drought adaptability and post-drought recovery among various bermudagrass （Cynodon dactylon） germplasms， this study assessed seven physiological indices in 18 germplasms under drought stress and subsequent rewatering， using a natural drought simulation method. The study aimed to clarify the variations in drought resistance and recovery capacity， identify superior germplasm， and determine key indicators through grey correlation analysis. The results showed that by the 12th day of drought， the contents of leaf chlorophyll a， chlorophyll b， total chlorophyll， and relative water content decreased significantly， whereas relative electrical conductivity， malondialdehyde， and proline contents increased significantly. Membership function analysis revealed that the D value for drought stress ranged from 0.056 to 0.725， while the D value for recovery after drought ranged from 0.239 to 0.828. Under drought stress conditions， germplasms C136， C75， and C92 showed higher D values （0.725、0.670、0.537， respectively）. In terms of post-drought recovery， C121， C92 and C136 had the highest D values （0.828、0.767、0.721， respectively）. Among the germplasms， the drought resistance and post-drought recovery capabilities of C136， C92， C100 and C22 were all higher than those of the four control variety. Grey correlation analysis indicated that chlorophyll a content was highly correlated with drought resistance， while leaf relative water content was highly correlated with post-drought recovery ability. These parameters can serve as important indicators for evaluating drought tolerance in bermudagrass.

In this study， whole oilseed rape at the full-bloom period and dried rice straw were used as silage materials. Seven treatments were established： Pediococcus acidilactici， Lactobacillus buchneri， Lactobacillus acidophilus， silage mixed powder of lactic acid bacteria and cellulase， Lactobacillus plantarum， Enterococcus faecalis， and a control group （CK）. Each treatment was replicated three times. The sensory characteristics， fermentation quality， nutritional composition， and aerobic stability of the mixed silage were analyzed at 90 days of ensiling to assess the effects of different bacterial additives on silage made from oilseed rape and rice straw. The results showed that the addition bacterial agents improved sensory evaluation， increased lactic acid production and lactic acid bacterial count， and reduced pH and protein loss in the silage. The ammonia nitrogen to total nitrogen in all additive-treated groups was significantly lower than that of CK （P<0.05）， except for the groups treated with Lactobacillus acidophilus and Enterococcus faecalis. However， dry matter content in the group of silage mixed powder of lactic acid bacteria and cellulase was significantly lower than that of CK （P<0.05）. Neutral detergent fiber and acid detergent fiber levels in silage mixed powder of lactic acid bacteria and cellulase and Lactobacillus plantarum treatments were significantly lower than those in CK （P<0.05）. Based on a grey correlation analysis， the ranking of silage quality among the seven treatment groups， from highest to lowest， was as follows： silage mixed powder of lactic acid bacteria and cellulase>Lactobacillus plantarum>Lactobacillus acidophilus>Pediococcus acidilactici>Lactobacillus buchneri>Enterococcus faecalis>CK. In conclusion， the addition of bacterial agents influenced the nutritional quality and fermentation quality of mixed silage of oilseed rape and rice straw. Among the treatments， the silage mixed powder of lactic acid bacteria and cellulase exhibited the best overall performance and was the most suitable additive for preparing mixed silage from oilseed rape and rice straw.

Objectives of this research are investigate the effects of the coupling of phosphorus solution-bacteria and phosphorus fertilizer on the phosphorus and soil enzyme activities in rhizosphere and non-rhizosphere soil of alfalfa， and to clarify the relationship between soil phosphorus utilization efficiency， soil fertility and dry matter yield. A two-factor completely randomized design was fitted with inoculation， single inoculation of Bacillus mucilaginosus （J₁）， Bacillus megaterium （J₂）， combination of two inoculants （J₃） and the no inoculation （J₀） as control and phosphorus application 100 mg/kg P₂O₅ （P₁） and 0 mg/kg （P₀） as control as fixed variables. Results of the research revealed phosphorus concentration and dry matter yield of plants was higher compared to control after inoculation under both phosphorus application levels， in which J₃ was the highest. Dry matter yield after inoculation improved 19.7%-40.7% for P₀ and 26.9%- 66.1% for P₁. Rhizosphere and non-rhizosphere alfalfa soil were improved significantly compared to control after inoculation on available phosphorus content， AKP， urease and sucrase activities except non-rhizosphere available phosphorus content and sucrase activity of first cut or non-rhizosphere AKP of second cut. For soil pH， a significant reduction was found in both rhizosphere and non-rhizosphere alfalfa soil. Phosphorus utilization efficiency of alfalfa soil was the highest （13.9%） when J₃ and P₁ applied. Bacterial inoculation and phosphorus application had significant effects on alfalfa plant phosphorus concentration， alfalfa dry matter yield， soil available phosphorus content， soil pH， soil AKP activity， soil urease activity， and soil sucrase activity. Bacterial-Phosphorus Coupling had effects on alfalfa plant phosphorus concentration， soil available phosphorus content， non-rhizosphere pH， and soil urease activity. Level of treatment combinations was ranked for response variables by comprehensive analysis as J₃P₁>J₁P₁>J₂P₁>J₃P₀>J₂P₀>J₀P₁>J₁P₀>J₀P₀. Correlation of dry matter yield to soil pH was negative， whereas positive correlation of dry matter yield to plant phosphorus concentration， available phosphorus content， AKP， urease and sucrase activity was found. Best treatment combination to promote soil fertility， alfalfa rhizosphere phosphorus utilization efficiency， and alfalfa dry matter yield was the combination of 100 mg/kg phosphorus application and Bacillus mucilaginosus×Bacillus megaterium co-inoculation.

In this study， oat seedlings （3 leaves 1 heart stage） of low nitrogen insensitive material As581 and low-nitrogen sensitive material As533 were treated with low nitrogen stress. After 12 h of stress treatment， roots and leaves were collected for transcriptome sequencing， in order to reveal molecular and signaling pathways related to low-nitrogen stress in oat， and lay a foundation for cloning and functional verification of candidate genes. The results showed that compared with As581， the sensitive material As533 had more significant differences in plant height， chlorophyll content， nitrogen content， leaf length， leaf width， leaf area， root shoot ratio， longest main root length， and root area under low nitrogen conditions. Under low nitrogen conditions， there were 466 differentially expressed genes in oat As581 and 1090 in oat As533. The differentially expressed genes in leaves of the two materials were more than those in roots， and most of them were down-regulated. GO analysis showed that both the root and leaf biological processes of As533 and As581 were enriched in metabolic processes， cell components were enriched in cell and cell components， and molecular functions were enriched in catalytic activities， binding and transport activities. KEGG analysis showed that As533 roots and leaves were enriched in phenylalanine metabolism， plant circadian rhythm and starch and sucrose metabolism pathways， while As581 roots and leaves were enriched in nitrogen metabolism， ABC transport， TCA cycle， metabolism of alanine， aspartic acid and glutamate， and oxidative phosphorylation pathways. RT-qPCR analysis of candidate genes associated to response to low nitrogen stress showed that the expression trend of differentially expressed genes was consistent with that of RNA-seq.

Heat shock transcription factor （HSF）， widely found in eukaryotes， are one of the most crucial transcriptional factors families in the plant resistance to heat stress. HSF has highly conserved DNA-binding domain （DBD）， which is involved in complex stress signal transduction and response networks. HSF， as a terminal component of the signal transduction chain， mediated the expression of target genes under abiotic stress. In response to stress， HSF is phosphorylated and ubiquitinated by upstream protein kinases or binds to heat shock elements （HSEs） through ABA signaling pathway to regulate the expression of downstream genes such as heat shock proteins （HSPs）， thereby improving plant stress resistance. In this study， the discovery， structure， classification， regulatory mechanism of HSF and its role in plant response to abiotic stress （extreme temperature， drought， high salinity， heavy metal， et al.） were reviewed， and the future research direction was expected to provide theoretical basis and gene resources for the genetic improvement of crop and forage stress resistance.

SWEET （Sugars will eventually be exported transporter） is a new type of sugar transporter protein. In this study， the MrSWEET gene family was identified and bioinformatical analyzed based on the genome of Medicago ruthenica， and the expression pattern of MrSWEET in drought and cold environment was preliminically analyzed by qPCR， in order to further explore the role of the SWEET gene family in abiotic stress in Medicago ruthenica. The results showed that there were 18 members in the SWEET sugar transporter protein family of Medicago ruthenica， all of which had MtN3_saliva/PQ-Loop domain. Phylogenetic analysis showed that SWEET sugar transporter protein family in Medicago ruthenica could be divided into four evolutionary branches， among which Clade Ⅰ included MrSWEET1a， -1b， -2a， -2b， -3a and 3b； Clade Ⅱ included MrSWEET4-6； Clade Ⅲ included MrSWEET9-15， and MrSWEET16 and 17 belonged to Clade Ⅳ. All MrSWEETs contained Motifs 1， 3， 4， and 5， which might be related to the function of sugar transporters. The MrSWEET genes promoter region contained cis-acting elements related to light response， hormone response， abiotic stress， and plant growth and development. Under drought （15% PEG6000） and cold （4 ℃） stresses， the expression level of MrSWEET genes in the root of Medicago ruthenica was relatively higher than that in the leaves， and the expression level of most genes in the root was highest at 6 and 12 h under drought and cold stress. The relative expression level of MrSWEET1a and MrSWEET16 in root was significantly upregulated at 3， 6， 12， 24 h and 7 d after drought， and the expression levels of MrSWEET16 and MrSWEET1a at 7 d after cold treatment were higher than CK, suggesting that they might be involved in regulating the response of Medicago ruthenica to drought and cold stresses.

In order to explore the effects of litter on the plant community characteristics and functional groups of desert steppe， this research focused on Stipa breviflora desert steppe in Inner Mongolia. A field control litter experiment （including no addition （CK）， adding 83.3 g/m² litter， and adding 166.6 g/m²） was conducted on degraded steppe under overgrazing for more than a decade. The results showed that the addition of litter improved community height， coverage， density and aboveground biomass under the adding 83.3 g/m² litter treatment， and the community height， coverage and aboveground biomass increased significantly by 2 cm， 3% and 9 g/m²， respectively. Plant community indices such as Simpson dominance index， Shannon-Wiene diversity index， Pielou evenness index and Margalef richness index were also increased significantly. The addition of litter enhanced the competition of perennial bunch grasses between perennial rhizome grasses and perennial forbs. Plants adapted to the environmental changes by altering the occupancy ratio of the functional groups. The addition of 83.3 g/m² litter had a more significant effect on plant community of the desert steppe. In conclusion， the input of appropriate amount of litter can help the recovery of degraded grassland by influencing the diversity of the community and the relationship between functional groups to promote the positive growth of grassland.

Grassland restoration is a critical pathway toward achieving sustainable utilization and high-quality development goals for degraded ecosystems. While scientific evaluation of restoration outcomes provides essential evidence for optimizing rehabilitation strategies， current methodologies predominantly focus on pre- and post-restoration changes in individual or limited indicators （e.g.， biomass， vegetation coverage）， with insufficient attention to comprehensive multi-indicator assessments. To address this issue， this study used factor analysis to comprehensively evaluate eight restoration approaches and nine ecological restoration effect assessment indicators for degraded grasslands in Chen Barag Banner， Inner Mongolia， aiming to identify representative community assessment indicators and suitable restoration approaches. The findings demonstrated that： （1） Three critical indicators-vegetation coverage， aboveground biomass， and community species richness-were identified as representative metrics for restoration evaluation. （2） The integrated approach combining fencing with root pruning， fertilization， and sustained management practices demonstrated superior restoration effectiveness. Our comprehensive quantitative assessment methodology exhibited both scientific rigor and practical applicability. These findings provide an evidence-based framework for evaluating and managing grassland restoration initiatives in Inner Mongolia's degraded steppes and comparable ecoregions.

This study investigated the effects of grazing on the seed dispersal and soil seed bank dynamics of Stipa breviflora， a constructive species in desert grasslands. The experiment employed a grazing gradient （including a grazing prohibition control） and measured several key variables within sample plots： vegetation cover， surface litter biomass， reproductive branch height of Stipa breviflora， and seed dispersal. Simulated rainfall experiments were conducted to assess the influence of precipitation on seed burial rate. The experimental design aimed to identify key factors influencing seed dispersal and incorporation into the soil seed bank under grazing disturbances. The results showed as follows： （1） Grazing intensity negatively affects seed quantity， increasing grazing intensity resulted in a decrease in seed number. （2） Seed dispersal was characterized by small-scale， localized dispersal. A significant positive correlation was observed between Stipa breviflora seed dispersal and reproductive branch height （P<0.05）. （3） Soil moisture content influenced the seed burial rate of Stipa breviflora， particularly within the 0-5 cm soil layer. A significant regression relationship was found between soil moisture in this layer and burial rate （P<0.05）.

This research aims to investigate the effects of variations in precipitation on the ecological stoichiometry of soil organic carbon （SOC）， total nitrogen （TN）， and total phosphorus （TP） in desert steppes and to reveal the response of C， N， and P and their ecological stoichiometry to precipitation gradients in desert steppe ecosystems. The experiment was conducted in temperate desert steppe on the southern edge of Mu Us Desert， Yanchi County， Ningxia Hui Autonomous Region. Five precipitation levels， 33%， 66%， 100%， 133%， and 166% of natural precipitation （G1， G2， G3， G4， G5）， were simulated by rainout shelters and manual water replenishment. Variation patterns of SOC， TN， TP contents across soil layers （0-10 cm，10-20 cm， and 20-30 cm） were analyzed under different precipitation levels. The results indicate that： （1） When precipitation increased （G4）， the SOC， TN， and TP contents， and soil C∶P and N∶P ratios in 10-20 cm and 20-30 cm soils were significantly lower than in 0-10 cm soils （P<0.05）. However， the TP content did not respond significantly to precipitation changes. （2） With the increasing of soil layer depth， the correlation between the contents and ratios of SOC， TN， and TP within soil followed the order of 20-30 cm>10-20 cm>0-10 cm； （3） The variation in the SOC， TN， and TP contents was the highest in the 20-30 cm layer， followed by the 10-20 cm， and was the lowest in 0-10 cm. The variation of soil TP content was the least for all the three soil layers. In conclusion， precipitation changes have a significant impact on the ecological stoichiometry of soil carbon， nitrogen， and phosphorus， and the variation of carbon， nitrogen， and phosphorus in deep soil is greater. Deep soil （20-30 cm） is more responsive to precipitation changes than surface soil （0-20 cm）， indicating that the ecological stoichiometry of desert steppe soils is more sensitive to precipitation in deeper layers.

Warming and nitrogen deposition can affect the functions and structures of alpine meadow ecosystems on the Qinghai-Xizang Plateau. Ecological stoichiometry provides a framework to understand the biogeochemical cycling of nutrients between plant and soil. This study conducted a field experiment in an alpine meadow of Qinghai Province， to investigate the effects of different levels of warming and nitrogen deposition. The warming treatment included four levels： W0 （no warming）， W1 （air temperature increases 0.47 °C， soil temperature increases 0.61 °C）， W2 （air temperature increases 0.92 °C， soil temperature increases 1.09 °C）， W3 （air temperature increases 1.44 °C， soil temperature increases 1.95 °C）. Nitrogen application treatments included： N0 （no nitrogen application）， 16 kg N/（hm²·a）， and 32 kg N/（hm²·a）. The experiment assessed changes in carbon， nitrogen， and phosphorus contents in plant and soil， soil enzyme activity， and their stoichiometric ratios， as well as the relationship among these components. The results showed as follows： Warming significantly increased total nitrogen in the aboveground plant tissues， soil total nitrogen， soil organic carbon， the soil nitrogen phosphorus ratio， and the enzyme nitrogen phosphorus ratio. Simultaneously， it significantly decreased the carbon nitrogen ratio in aboveground plant biomass， and the carbon nitrogen and carbon phosphorus ratios of soil enzymes. Nitrogen deposition significantly increased total nitrogen in both aboveground and root tissues， soil organic carbon， soil total nitrogen， and the enzyme carbon nitrogen ratio. It significantly decreased the root carbon nitrogen ratio and enzyme nitrogen phosphorus ratio. The interaction between nitrogen deposition and warming significantly affected soil organic carbon content and the carbon nitrogen， carbon phosphorus， and nitrogen phosphorus ratios of soil enzymes. Analysis of stoichiometric homeostasis in plant tissues in responses to soil elements and enzyme activities revealed strict stoichiometric homeostasis in plant tissues under both warming and nitrogen deposition. Soil total nitrogen， soil carbon nitrogen ratio， and soil β-1， 4-xylosidase activity significantly influenced plant nutrient content and stoichiometry. In summary， short-term warming and nitrogen deposition significantly alter the stoichiometry of soil and enzyme systems in alpine meadows， which in turn influences the nutrient acquisition strategies of plants on the Qinghai-Xizang Plateau.

This study employed multivariate statistical methods， including analysis of variance （ANOVA）， principal component analysis （PCA）， correlation analysis， hierarchical cluster analysis， and membership function evaluation， to comprehensively analyze and evaluate five seed morphological traits of 329 wildrye （Agropyron cristatum） accessions conserved in the National Crop GeneBank. The objective was to establish a theoretical framework for the evaluation and innovative utilization of A. cristatum （L.） Gaertn germplasm resources. The results showed that among the five phenotypic traits examined， thousand-seed weight exhibited the highest genetic variation， with a genetic diversity index of 1.880 and a coefficient of variation of 24.56%. The average genetic diversity index for all five traits was 1.752， and the average coefficient of variation of 14.06%. PCA extracted three principal components， explaining 98.750% of the trait variation， with the first three main components contributing 65.555%， 26.162%， and 7.034% respectively， effectively preserving the core genetic information of seed traits. Correlation analysis demonstrated extremely significant positive correlations between seed length with the other four phenotypic traits （P<0.01）. Additionally， significant positive correlations were observed between seed width and both thousand-seed weight and single-seed area （P<0.01）， between thousand-seed weight and seed length-width ratio， as well as between seed length-width ratio and single-seed area. Hierarchical cluster analysis categorized the accessions into four groups： Group Ⅰ （284 accessions， moderate）， Group Ⅱ （41 accessions， small-grained）， and Groups Ⅲ and Ⅳ （two high-quality unique accessions each）. Comprehensive evaluation using the membership function identified B-288， B-243， B-233， and B-250 accessions with excellent performance in seed length， seed width， single-seed area， and thousand-seed weight. In contrast， B-152， B-143， B-128， B-149， B-141， and B-153 accessions exhibited relatively weak performance across multiple traits. In conclusion， seed length， single-seed area and thousand-seed weight were identified as the key morphological indicators contributing to the genetic diversity of A. cristatum germplasm.

The overexploitation of agro-pastoral systems has driven widespread grassland reclamation in northern China，accelerating soil carbon and nutrient depletion. However，the mechanisms underlying the responses of soil organic carbon （SOC） and its fractions to grassland cultivation remain unclear. In this study，we investigated the effects of grassland reclamation on soil physicochemical properties and SOC fractions across three representative sites in the agro-pastoral ecotone： Jianping （Liaoning），Youyu （Shanxi），and Yuzhong （Gansu）. Cultivation significantly increased soil nitrate nitrogen but reduced SOC content by 24.17%. Among SOC fractions，labile free particulate organic carbon （fPOC） decreased significantly，whereas occluded particulate organic carbon （oPOC） and mineral-associated organic carbon （MAOC） remained unchanged. Random forest analysis identified soil electrical conductivity，moisture，and the carbon-to-nitrogen （C/N） ratio as the primary regulators of SOC and its fractions. Specifically，SOC and MAOC were mainly influenced by soil electrical conductivity and moisture，while the C/N ratio was the dominant driver of SOC and fPOC dynamics. Overall，grassland cultivation selectively depleted labile carbon pools while maintaining oPOC and MAOC，a process largely mediated by shifts in soil electrical conductivity，moisture，and the C/N ratio，ultimately reshaping SOC distribution and stability.

Moisture content is a key indicator of seed quality，and its accurate and rapid determination is essential for seed grading. With the increasing use of seed coating technology in seed production and trade，traditional high （low） constant-temperature method often severely underestimated the actual moisture content of coated seeds due to the influence of coating materials. To address this issue，four coated forage species： Medicago sativa，Elymus dahuricus，Lolium perenne and Dactylis glomerata，were selected as experimental materials. By analyzing the relationship between water activity of coated seeds and the moisture content of naked seeds，a predicted model for coated seeds moisture content based on water activity was developed. The goodness-of-fit values of the prediction models for the four species were 0.9003，0.9124，0.9076，and 0.9323，respectively，with relative errors of 2.87%，4.08%，3.07% and 4.14%. These results indicated that seed water activity can serve as a reliable，non-destructive，and rapid indicator for determining the moisture content of coated seeds.

In this research， effects of varying apple pomace to citrus pulp ratios on the volatile compounds were analyzed by headspace-gas chromatography-mass spectrometry to evaluate the odor composition of wheat straw mixed silage. Silage was fermented for 45 days using mixtures of citrus pulp and apple pomace at mass ratios （m/m） of 0∶4 （T0）， 1∶3 （T1）， 2∶2 （T2）， 3∶1 （T3）， and 4∶0 （T4）. The water content was adjusted to approximately 65% by adding wheat straw. The results showed that the ammonia nitrogen content of T2， T3 and T4 groups was less than 5%， and there was no significant difference in silage pH and lactic acid content. Compared with T0， the relative abundance of Lactobacillus （P<0.05） in T4 was significantly higher， while relative abundances of Enterobacter and Weissella （P<0.05） were lower. The contents of esters such as ethyl acetate and 2-methylbutyl acetate gradually increased with the increase in apple pomace mixing ratio， while the contents of terpenes such as D-limonene and α-acacia gradually decreased. The relative abundance of Enterobacter positively correlated with acetic acid， ammonia-nitrogen， and D-limonene contents （P<0.01）， and had negative correlation with lactic acid， ethyl acetate， and 2-methylbutyl acetate contents （P<0.01）. In summary， the 2∶2 mixture of apple pomace-citrus pulp improved fermentation quality and volatile compound profiles， and maximized citrus pulp utilization efficiency.

To explore the effects of different grazing intensities on soil microbial biomass in alpine meadow，this study investigated the variation characteristics in soil microbial biomass and interactions between soil physicochemical properties and microbial parameters including biomass，microbial quotient，and stoichiometric ratios under no grazing （CK），light grazing （LG），moderate grazing （MG），heavy grazing （HG），and extreme grazing （EG） conditions in the alpine meadow of Tianzhu Zangzu Autonomous County on the northeastern edge of the Qinghai-Tibet Plateau. The results showed that both microbial biomass carbon （MBC） and phosphorus （MBP） reached the maximum levels under LG，which were significantly higher compared with EG condition （P<0.05）. Soil microbial biomass nitrogen （MBN） was highest under HG，followed by MG，while MBN was significantly lower under EG compared with HG （P<0.05）. Soil microbial quotient carbon （qMBC），microbial quotient phosphorus （qMBP） and the MBC∶MBN ratio were all highest under LG，whereas microbial quotient nitrogen （qMBN），MBC∶MBP ratio，and MBN∶MBP ratio were highest under MG. Soil bulk density emerged as the predominant factor influencing microbial biomass，microbial quotients，and their stoichiometric ratios. These findings indicate that both light and moderate grazing intensities benefit the accumulation of microbial biomass and promote efficient utilization and transformation of soil nutrient in alpine meadows. In contrast，extreme grazing leads to soil fertility decreasing and a reduction of microbial biomass. A win-win scenario of ecology sustainability and economic benefits will be achieved when apporiate grazing intensities adopted.

This research aimed to explore the alleviating effects of exogenous abscisic acid （ABA） and hydrogen sulfide （H₂S） treatments on aluminum toxicity in perennial ryegrass.Growth and photosynthetic parameters of perennial ryegrass 'Mathilde' seedlings exposed to 500 mg/kg aluminum stress were measured under five treatments： CK，aluminum （Al），Al+0.4 mmol/L ABA，Al+1.2 mmol/L H₂S，and Al+0.4 mmol/L ABA+1.6 mmol/L H₂S. The results showed that the growth of ryegrass was significantly inhibited under aluminum stress，with 43.33% decrease of the root length compared with CK. Compared to aluminum treatment alone，exogenous ABA and H₂S significantly increased root length，plant height，aboveground and underground biomass of ryegrass. Specifically，the root lengths under the ABA treatment，H₂S treatment，and ABA+H₂S treatment were increased by 63.92%，58.83%，and 71.37%，respectively，and the plant heights were increased by 18.86%，27.43%，and 33.71%，respectively. Individual or combined application of exogenous ABA and H₂S significantly increased the contents of chlorophyll a，chlorophyll b，and total chlorophyll. In addition，the intercellular CO₂ concentration decreased significantly，while the net photosynthetic rate，stomatal conductance，and transpiration rate increased significantly. Among them，after the combined addition of ABA and H₂S，the chlorophyll b，total chlorophyll content and net photosynthetic rate increased the most. In contrast，individual application of ABA induced transpiration rate even exceeded that of the CK. Exogenous ABA and H₂S were considered to mitigate aluminum-induced growth inhibition in perennial ryegrass，to enhance leaf photosynthetic pigments accumulation，to reduce photosystem damage，and to improve photosynthesis. Comprehensive evaluation revealed that the aluminum toxicity mitigation effects followed the order of ABA+H₂S>ABA>H₂S.

As a high-value cool-season grass species cultivated worldwide，perennial ryegrass （Lolium perenne L.） frequently faces various abiotic stresses. Fructans are the primary reserve carbohydrates in perennial ryegrass，which play a crucial role under abiotic stress conditions and significantly enhance stress tolerance. This article reviews research progress on fructan metabolism in perennial ryegrass in China and internationally，focusing on its biosynthesis and degradation pathways，as well as the regulatory mechanisms of certain biomolecules on fructan metabolism. In addition，metabolic changes and underlying mechanisms of fructans in perennial ryegrass were illustrated under various abiotic stresses including drought，low temperature，salinity，waterlogging，nitrogen deficiency，and mowing，with prospects on future research directions.

This study investigated the effects of different zinc （Zn） fertilizer types of on the growth， yield， quality， and Zn enrichment of Leymus secalinus， aiming to identify optimal foliar fertilization protocols. Potted L. secalinus were treated with inorganic （ZnSO₄-7H₂O） and chelated （EDTA-Zn， referred to as E-Zn） fertilizers at Zn concentrations of 0.2， 0.4， and 0.8 mg/g. Water served as the control （CK）. A comprehensive analysis of L. secalinus indicators was conducted using the grey correlation method to identify the most suitable micro-fertilizer form and concentration for improving trace element content and overall quality. The results showed that foliar application of appropriate concentrations of ZnSO₄ and E-Zn significantly promoted the plant height and stem thickness of L. secalinus， leading to increased biomass. Both fertilizer types significantly increased contents of crude protein， ether extract and Zn （P<0.05）， while significantly reducing acidic detergent fiber and neutral detergent fiber （P<0.05）， thereby improving the quality of L. secalinus. Notably， the absorption efficiency of Zn from E-Zn was significantly superior to that from ZnSO₄ at the same concentration. The comprehensive gray correlation analysis indicated that foliar spraying with E-Zn consistently outperformed ZnSO₄ across different concentrations. The optimal L. secalinus yield and quality were achieved at an E-Zn concentration of 0.4 mg/g.

Effective restoration measures such as organic fertilizer application and no-tillage reseeding， can significantly influence the composition and stability of soil aggregates and ecosystem nutrient cycling processes in degraded alpine meadows of the Yellow River Basin. In this research， effects of different restoration measures on soil aggregate composition， aggregate stability， and carbon， nitrogen， and phosphorus content of soil aggregates and their ecological stoichiometric characteristics were determined to provide fundamental data for understanding changes in soil structure and function during vegetation restoration of degraded alpine meadows in the Yellow River Basin， and to offer essential references for ecosystem restoration and reconstruction. In 2020， three ecological restoration measures， organic fertilizer application （F）， no-tillage reseeding （S）， and combination of organic fertilizer application and no-tillage reseeding （F+S） were conducted in degraded alpine meadows for a three-year field trial， with untreated meadows serving as controls （CK）. Results demonstrated that compared with CK， S significantly increased silt and clay aggregate content （P<0.05）， while F+S significantly increased micro-aggregate content （P<0.05）. Conversely， S significantly inhibited mean weight diameter （MWD） （P<0.05）. Total nitrogen and phosphorus content in micro-aggregates were increased by F+S （P<0.05）， whereas organic carbon contents in micro-aggregates and silt and clay aggregates were reduced by S significantly （P<0.05）. For carbon-to-phosphorus ratios， increases were found in micro-aggregates and silt and clay aggregates under F and F+S （P<0.05）， while the ratio in meso-aggregates was risen by S （P<0.05）. Additionally， nitrogen-to-phosphorus ratios in all aggregate compositions were increased by F and F+S （P<0.05）. The organic carbon content in micro-aggregates and silt and clay aggregates significantly affect macro-aggregate and silt and clay aggregate content， MWD， and geometric mean diameter （GMD） （P<0.01）. In conclusion， after three years of treatment， the soil aggregate properties and major chemical characteristics of degraded alpine meadows in the Yellow River Basin were effectively improved by organic fertilizer application and no-tillage reseeding treatments， with the organic fertilizer application+no-tillage reseeding combination being considered as the most optimal restoration mode.

In order to investigate the root-specific genes regulating root growth of alfalfa （Medicago sativa），transcriptome sequencing was performed to analyze differentially expressed genes （DEGs） and their functions between the aerial parts （stems and leaves） and root system of alfalfa cultivar Zhongmu No. 1. The results showed that compared to aerial parts，a total of 15258 DEGs were identified in root system，including 5095 up-regulated and 10163 down-regulated. The GO functional annotation demonstrated significant enrichment of these DEGs in cellular process，metabolic regulation，and biocatalytic activities. KEGG pathway enrichment analysis showed significant enrichment of these DEGs in pathways related to porphyrins and chlorophyll metabolism，photosynthesis-antenna protein synthesis，and carbon fixation in photosynthetic organisms. Six candidate up-regulated genes exhibiting significant differential expression were selected for real-time quantitative PCR validation. The results indicated high concordance between their expression patterns and transcriptome sequencing data.

To investigate the genetic variation characteristics and agronomic potential of the polycotyledon trait in alfalfa （Medicago sativa L.），this study evaluated the phenotypic diversity of alfalfa cotyledonous mutations under field cultivation. Eleven agronomic quantitative traits were assessed using the Kruskal-Wallis non-parametric test，mean analysis method，and the entropy-weight TOPSIS method. The results showed that： （1） The polycotyledonous mutation rate in the test population was 1.44%，with 29 phenotypic variation patterns were identified；（2） the B8 type （tricotyledon-one unifoliolate true leaf-normal main stem-erect branches） exhibited the highest mutation rate （41.28%），followed by the B2 type （dicotyledon-two unifoliolate true leaves-normal main stem-erect branches） at 8.74%；（3） Mean analysis indicated that differences among variant types were mainly associated with branch number and plant height；（4） The entropy-weight TOPSIS evaluation ranked the B2 type highest （score： 0.8389），followed by the B8 type （0.6297），whereas the B12 type （tricotyledon-one unifoliolate true leaf-clustered branch） scored lowest. This study provides the first systematically characterization of phenotypic diversity and agronomic polycotyledonous alfalfa variants and offers novel mutant germplasm resources for breeding innovation.

Carbendazim is widely used for prevention and control of leaf diseases in maize （Zea mays L.）. However， the effects of different carbendazim concentrations on silage maize yield and fungal community structure were lack of research. In this research， serial dilutions of 1∶1500 （low）， 1∶1000 （medium）， and 1∶500 （high） carbendazim （80% active ingredient， wettable powder） solutions were applied to investigate their effects on silage maize agronomic traits and fungal community structure during three growth period （big trumpet stage， milk stage， and dough stage）. The results revealed that compared with big trumpet stage， the plant height and leaf area of silage maize were increased significantly at the milk and dough stages （P<0.05）. Fresh weight per plant of silage maize under medium and high concentrations were decreased by 22.04% and 11.82%， respectively， compared with the low concentration. The contents of total phenolics， reducing sugars， vitamin C， free amino acid， and phosphorus， and mold count were significantly higher at the dough stage （P<0.05） compared with the big trumpet and milk stages. Carbendazim concentration had no significant effects on chemical properties of silage maze such as total phenolics， proline， reducing sugars， vitamin C， soluble protein， free amino acid， and phosphorus. Diversity analysis of fungi identified 186，186 and 202 OTUs under the application of low， medium， and high concentrations of carbendazim， respectively. At the genus scale， Symmetrospora， Papiliotrema， Hannaella， Filobasidium， and Cladosporium were the five fungi with the highest relative abundances. Under different carbendazim concentrations， the relative abundances of Symmetrospora， Phoma， and Hypoxylon varied significantly （P<0.05）. The determination coefficient of vitamin C content for molds and soluble protein for yeast counts was the highest whereas free amino acid content was the lowest. Considering the yield， utilization pattern， as well as species and relative abundances of epiphytic fungi， the low concentration of carbendazim was recommended to be applied.

This study investigated the impact of grassland subsidy and reward policy on the occupational differentiation of herder households by constructing Probit and Tobit models based on household survey data collected in 2010 and 2015 across five distinct grassland types in the Inner Mongolia Autonomous Region： meadow steppe， typical steppe， desert steppe， sandy grassland， and steppe desert. Subgroup regression analyses were further conducted to explore the heterogeneous effects of the policy on herders' occupational differentiation across these different grassland types. The results showed that following the implementation of the grassland subsidy and reward policy， 55.25% of herder households experienced occupational differentiation， indicating a significant trend toward occupational transition. Among these households， 48.40% shifted to non-herding occupations， while only 6.85% specialized in pastoralism， demonstrating a prominent tendency non-herding activity. The policy significantly promoted occupational differentiation among herder households and particularly encouraged shifts toward non-herding occupations. However， it also had a suppressive effect on the degree of occupational specialization within pastoralism. The impact varied by grassland types： it facilitated differentiation toward herding occupations in meadow steppe area， whereas in other grassland types， it primarily promoted transitions toward non-herding occupations. To ensure the robustness of these results， three verification methods were employed： redefining key explanatory variables， introducing additional control variables， and applying multiple econometric approaches. The results remained consistent across all robustness checks. Based on these findings， this study recommends optimizing the grassland ecological conservation subsidy and reward mechanism to better support the livelihoods of herders undergoing occupational transitions. In addition， efforts should be made to strengthen human capital development to facilitate integration into non-herding sectors.

Overexploitation and improper management of grasslands have intensified the conflict between grassland resources and livestock production， underscoring the necessity of implementing grassland-livestock balance management to alleviate these tensions. This study analyzed the evolution and research trends in grassland-livestock balance using data retrieved from the China National Knowledge Infrastructure （CNKI） and visualized with CiteSpace software. Furthermore， the study identified current hotspots and potential future directions within this field. The results showed three distinct phases in the research output from 1986 to 2023： a slow growth phase （1986-2002）， a fluctuating growth phase （2003-2012）， and a stable growth phase （2013-2023）. The total number of publications exhibited an increasing trend， and a cluster of influential research institutions emerged during the study period. However， inter-regional collaboration among authors and institutions was limited， indicating a weak overall correlation. Key word co-occurrence and cluster analysis identified three primary research hotspots： balanced development of grassland ecological animal husbandry， accounting and monitoring systems for grassland-livestock balance， and policy incentives and development strategies. Key word burst analysis indicated that since 2020， research has increasingly focused on themes such as grazing prohibition， family ranches， and grassland ecology. Therefore， it is suggested that future research should emphasize the management and monitoring system for grassland-livestock balance， standardizing the calculation methodologies for dynamic carrying capacity， and addressing existing challenges in grassland-livestock balance incentive policies， to promote sustainable grassland utilization within the framework of ecological civilization construction.

Alfalfa （Medicago sativa） was introduced into China following Zhang Qian's diplomatic missions to the Western Region during the Han Dynasty. However， scholarly consensus regarding its precise provenance remains elusive. This study critically examines the origin of alfalfa in Han China by analyzing 43 historical texts from various periods that document its source， integrated with modern research findings. Our analysis reveals significant discrepancies in the proposed origins of Han-era alfalfa across ancient records and contemporary studies， coalescing into six primary hypotheses： （1） the Western Regions broadly； （2） Dayuan （Ferghana）； （3） Jibin （Kashmir region）； （4） Wusun； （5） Anxi （Parthia）； and （6） unspecified foreign lands. While Wang Yi of the Eastern Han Dynasty was the first scholar documented to explicitly associate alfalfa with the Western Regions， his era postdates those of Zhang Qian， Sima Qian， and Ban Gu. Consequently， the attribution solely to the broader Western Regions lacks substantive historiographical support. Alfalfa was firstly recorded in Shiji·Dayuan Liezhuan， and there were abundant similar records in the later historical books， that is， it is certain that the alfalfa in the Han Dynasty came from Dayuan and was brought from Dayuan by the Han envoys to the Western Regions. Although no extant texts explicitly record the introduction of alfalfa from Jibin to the Central Plains， the possibility cannot be entirely excluded following the initial introduction from Dayuan， as suggested by relevant accounts in the Hanshu （Book of Han）， Xiyu Zhuan （Account of the Western Regions）. The proposed origins from Wusun， Anxi， or other unspecified foreign lands lack convincing support from primary historical sources and warrant further validation.