Methane （CH₄） is recognized as the second-largest contributor to greenhouse gas emissions. The enteric fermentation from ruminant livestock accounts for approximately 40% of the total anthropogenic CH₄ emissions. This poses a major obstacle to national efforts in combating global warming and achieving the “dual carbon goals”. In this study， we systematically synthesized the existing knowledge on enteric methane emissions from ruminant livestock and their measurement methods. The results indicated that there were significant variations in CH₄ emission factors across regions， livestock species and feeding stages. There was a larger span of emissions in warmer and humid regions than in colder and drier regions. Larger-bodied animals generally produced higher emissions. For example， female breeding buffaloes emited up to 110.6 kg·head^-1·a^-1， whereas emissions from sheep and goats were considerably lower （approximately 12~13 kg·head^-1·a^-1）. Overall， the emission factors ranged widely from 6.5 to 110.6 kg·head^-1·a^-1 depending on production stages and feeding systems. Key measurement techniques for enteric methane included the sulfur hexafluoride （SF₆） tracer technique， respiration chamber/headbox systems， the GreenFeed system， in vitro fermentation， laser-based methods， and predictive modeling. Promising mitigation strategies encompassed dietary composition adjustments， feed additives， rumen microbiota manipulation， vaccine-based methods， genetic improvement， and optimized management practices， as well as emerging approaches such as targeted inhibition of key methanogenic enzymes， modulation of hydrogen metabolic shunting， and remodeling the rumen microbiome through gene editing. Future studies should prioritize establishing accurate methodologies for accounting enteric CH₄ emissions throughout the entire production cycle. In addition， more studies are needed to refine region-specific emission factors. For greenhouse gas mitigation， efforts should focus on improving dietary formulations， integrating farm management， and implementing genetic selection programs to promote the sustainable development of ruminant livestock production.

To investigate whether seasonal freeze-thaw promotes the emission of nitrous oxide （N₂O） and accelerates the gaseous loss of nitrogen in the talus plateau vegetation ecosystem， this study focused on the grassland （Thylacospermum caespitosum） pad vegetation at an altitude of 4000-4400 m on the Gangshigacha snow peak in the eastern part of the Qilian Mountains. The soil （0-30 cm） temperature， humidity， nutrient dynamic characteristics， and N₂O flux were monitored continuously for two years. The results showed that the soil experienced approximately 70 daily freeze-thaw cycles throughout the year， divided into four periods： unstable thawing period （25 times）， stable thawing period， unstable freezing period （45 times）， and stable freezing period. For every 100-meter increase in altitude， the average start and end time of soil freeze-thaw was delayed or advanced by 3.88 days. The N₂O emission was the most significant during the unstable thawing period （accounting for only 5.5%-6.8% of the entire year）， with a cumulative emission （225.97 g·hm^-2） accounting for 35.88% of the annual total， a maximum emission rate of 24.52 μg·m^-2·h^-1， an average flux of 13.63 μg·m^-2·h^-1， which was 1.39 times the annual average， and the cumulative emission during the non-growing seasons （excluding the stable thawing period） accounted for as high as 74.09%. The emission was dominated by soil water and heat， pH， and substrate scarcity， leading to low production. Under climate warming， the freeze-thaw driven nitrogen gas loss of N₂O in the ice margin zone intensified， and further research on the water and heat conditions and nitrogen transformation mechanism is needed.

To determine the optimal drying duration for forage oat （Avena sativa L.） hay preparation and mitigate fungal contamination risks， this study monitored microbial counts and the succession of fungal communities on oats and the attached topsoil during the drying process （days 1-5）. The results showed that with prolonged drying time， the counts of molds， yeasts， coliforms， and aerobic bacteria in both oats and topsoil generally exhibited a logarithmic growth trend. Specifically， aerobic bacteria counts remained at their lowest levels on days 1-2， while mold counts peaked on day 3. Notably， from days 2 to 5， the counts of molds and aerobic bacteria significantly exceeded the limits specified in the Hygienic Standard for Feeds （GB 13078-2017）. Regarding community structure， Ascomycota （72.24%） and Basidiomycota （21.10%） were identified as the dominant phyla. The dominant genera on the oat surface exhibited a distinct succession pattern： the relative abundances of Bulleromyces （19.22%） and Sarocladium （16.12%） decreased with prolonged drying， whereas those of Microdochium （15.14%） and Cryptococcus （11.07%） significantly increased. Correlation network analysis indicated that the fungal community network underwent a topological shift from a simple， sparse structure in topsoil to a complex， dense structure on oat plants. Furthermore， correlation analysis revealed a succession path of potential pathogens： the community dominated by potential toxin-producing or endophytic pathogenic taxa （represented by Sarocladium and Acremonium） in the topsoil gradually evolved into a community dominated by soil-borne root rot pathogens （represented by Plectosphaerella and Idriella） on the plants. In conclusion， to inhibit pathogen colonization and ensure the hygienic quality of hay， it is recommended to control the drying duration within 1-2 days in production practice.

Grazing is one of the main ways to utilize grassland. A reasonable grazing method can achieve sustainable utilization of grassland. However， most studies focus on grazing of a single livestock species or fixed-proportion mixed grazing， lacking exploration of the impact of different proportion mixed grazing on grassland ecosystem. This study investigated the effects of different herbivore assemblage grazing on soil nutrients and enzyme activities based on the alpine grasslands of the Qinghai-Tibet Plateau. The experiment was established including a control （CK）， yak-only grazing （YG）， Tibetan sheep-only grazing （SG）， and mixed grazing of yaks and Tibetan sheep （MG1∶2， MG1∶4， MG1∶6）. Plant and soil samples were collected from the experimental plots from the 6th to the 8th year of grazing to analyze changes in grassland plant biomass， soil total nutrients （total carbon， total nitrogen， total phosphorus）， and the activities of enzymes related to carbon and nitrogen cycles （nitrate reductase， nitrite reductase， urease， hydroxylamine reductase， amylase， and neutral protease）. The results showed that both grazing patterns and experimental year had significant interactive effects on the activities of carbon- and nitrogen cycle-related soil enzymes. Soil nutrients and enzyme activities exhibited significant interannual dynamic characteristics. Mixed grazing had distinct effects on soil nutrients and enzyme activity compared to single-species grazing. As the grazing duration increases， the mixed grazing system with a yak-to-Tibetan sheep ratio of 1∶2 or 1∶4 gradually restores the soil nutrients and enzyme activity of alpine grasslands to levels closer to those of natural grasslands. The results suggest that grazing with different livestock combinations is more conducive to maintaining the stability of grassland ecosystem functions.

MYB-related gene family plays important roles in plant growth， development， and stress response. This study analyzed the number， evolutionary relationships， gene structure， and physicochemical properties of MYB-related family genes in Atraphaxis bracteata by bioinformatics methods based on the full-length transcriptome data of A. bracteate. The qRT-PCR was used to analyze the temporal and spatial expression patterns of these genes in various tissues of A. bracteata under drought stress， and to analyze their response to drought stress. The results showed that a total of 55 MYB-related family members of A. bracteata were identified and divided into 5 subgroups. The encoded proteins were mostly hydrophilic and mainly located in the nucleus. Motif 2 was the characteristic motif， while Motif 4 had the highest conservation. The secondary and tertiary structures of their proteins were mainly irregularly coiled. Expression analysis showed that after 24 h of drought stress， gene expression levels were higher than those at 6 h and 0 h， and most of these genes were highly expressed in the leaves. These genes responded more strongly in roots and stems under severe drought， while they had higher expression levels in leaves under mild drought. In summary， the MYB-related gene family of A. bracteata exhibited distinct tissue-specific expression patterns under drought stress， laying a theoretical foundation for subsequent functional research and stress resistant breeding.

Laccase （LAC）， as an important member of the ceruloplasmin protein family， plays a key role in the regulation of plant growth and development and the response to abiotic stress. In this study， the local superior germplasm of Medicago sativa ‘Pianguan’ in Shanxi Province was used as the experimental material. The MsLAC17 gene was cloned by PCR. And was analyzed by bioinformatics means and fluorescence quantitative PCR technology. The tissue specificity expression of MsLAC17 gene and its response under different abiotic stresses were systematically explored. The results showed that the length of the MsLAC17 gene is 1782 bp， encoding 593 amino acids. The relative molecular mass of this protein is 66.26 kDa， and its theoretical isoelectric point is 10.05. It is a hydrophilic protein mainly located in chloroplasts and mitochondria. The results of phylogenetic analysis indicated that the LAC17 protein of Medicago sativa ‘Pianguan’ is closely related to that of Medicago truncatula. Fluorescence quantitative PCR detection revealed that the expression level of the MsLAC17 gene was the highest in the stem， and responded to salt， drought and ABA treatment. It is speculated that this gene may play a role in regulating the response of Medicago sativa ‘Pianguan’ to abiotic stress. The results of this study provide an important basis for further clarifying the biological function of the MsLAC17 gene.

WRKY transcription factors are widely involved in plant growth and development and play important roles in biotic and abiotic stress responses. In this study we cloned the EnWRKY26 gene from Elymus nutans Griseb ‘Ba Qing’ and conducted bioinformatics analysis， subcellular localization analysis， gene expression profiling， and transcription factor activity validation. The results indicated that EnWRKY26 was 996 bp in length， encoding 331 amino acids， with a molecular weight of 35 501.70 Da. The theoretical isoelectric point of the EnWRKY26 protein was 9.49， with an instability index of 53.78 and an average hydrophobicity of -0.652， indicating that it was an unstable hydrophilic protein. The entire protein sequence lacks transmembrane domains， and its secondary structure is predominantly composed of random coils. EnWRKY26 is most closely related to TraseCS7B02G418600 and TraseCS7D02G497700 in terms of phylogenetic relationship. Subcellular localization analysis revealed that EnWRKY26 was localized in the nucleus. Transcription factor activity validation confirmed that it possesses transcriptional activation activity. Under salt stress treatment， the relative expression level of EnWRKY26 showed an increasing trend. This study provides a theoretical basis for an in-depth understanding of the molecular mechanism by which EnWRKY26 regulates the response of Elymus nutans to salt stress.

Chicory （Cichorium intybus L.） is a perennial forage extensively utilized in livestock production. The magnesium-dechelatase involved in chlorophyll degradation plays a pivotal rolein regulating chlorophyll breakdown and is a key factor in the control of stay-green traits of plants. Enhancing the stay-green phenotype is critical for improving chicory’s resilience to environmental stresses. In this study， two putative SGR （Stay-Green） genes were preliminarily identified in the chicory genome， and designated as CiSGR and CiSGRL based on their respective phylogenetic affiliations to the SGR and SGRL subfamilies. The proteins encoded by these genes were composed of 274 and 232 amino acids， respectively. Structural domain analysis revealed that both CiSGR and CiSGRL possessed chloroplast transit peptide domains， highly conserved SGR domains， and variable regions at the C-terminus. Cis-regulatory element analysis indicated that the promoters of CiSGR and CiSGRL contained light-responsive， hormone-related， and stress-inducible transcriptional elements. Subcellular localization assays demonstrated that CiSGR predominantly localized to chloroplasts and nuclei， whereas CiSGRL primarily resided in nuclei and cytoplasm. Tissue-specific expression profiling showed the highest transcript levels of both genes in stems and significant induction under six different abiotic stress conditions. This systematic identification and analysis of chicory SGR and SGRL genes provides a theoretical foundation for strategies aimed at improving chicory forage yield and quality.

To provide a theoretical basis for the breeding of salt-tolerant germplasm resources in Bothriochloa ischaemum， this experiment investigated the effects of ascorbic acid （AsA） priming on the AsA-GSH cycle in the embryonic mitochondria of B. ischaemum under salt stress. Seeds of ‘Taihang’ B. ischaemum were used as experimental materials， and were primed with 0.1 mmol·L^-1 AsA solution for 12 h， then were germinated in NaCl and Na₂SO₄ solutions containing 30 mmol·L^-1 Na⁺. The changes in AsA-GSH cycle enzymes activities and lipid peroxidation levels in their mitochondria of radicle and plumule were analyzed. The results showed that the activities of catalase （CAT）， glutathione transferase （GST）， dehydroascorbate reductase （DHAR） and monodehydroascorbate reductase （MDHAR） in the mitochondria of radicle and plumule of B. ischaemum were increased significantly after AsA priming （P<0.05）， while the activities of superoxide dismutase （SOD）， ascorbate peroxidase （APX） and glutathione peroxidases （GPX）， as well as the contents of malondialdehyde （MDA） and H₂O₂， were decreased significantly （P<0.05）. Under salt stress， APX and GPX were the key enzymes regulating salt tolerance of embryonic mitochondria in B. ischaemum， but CAT， MDHAR and DHAR were served as the core regulatory enzymes after AsA priming. The membership function analysis indicated that priming with 0.1 mmol·L^-1 AsA had the best effect on enhancing the activities of mitochondrial AsA-GSH cycle enzymes in the radicle of B. ischaemum under 30 mmol·L^-1 NaCl stress.

This study conducted a preliminary investigation on the rhizosphere fungi diversity of Kobresia humilis in the source region of the Yellow River， aiming to screen plant growth-promoting strains and provide basic materials for the future development of microbial fertilizers. Rhizosphere soil samples of K. humilis were collected from five different altitude sites in the source region of the Yellow River. Fungal strains were isolated and purified， then identified based on morphological and molecular biological methods. The plant growth-promoting activities of the dominant species Trichoderma paraviridescens were evaluated. A total of 207 fungal strains belonging to 18 genera were isolated. Among them， Fusarium and Trichoderma were the dominant genera， with 67 and 55 strains isolated， respectively， corresponding to isolation frequencies of 32% and 27%. Diversity index analysis revealed that the fungal diversity was the highest in Gonghe County （3208 m； H'=0.9381） and lowest in Maduo County （4512 m； H'=0.3378）. The overall fungal diversity in the study area was relatively low （H'=2.0809）. Both the diversity index and evenness index of rhizosphere fungi showed a trend of initial decrease followed by an increase with rising altitude. Analysis of the plant growth-promoting activities of the 55 T. paraviridescens strains indicated that 53 strains had the ability to produce cellulase， 51 strains possessed ability to produce protease， 32 strains had the ability to dissolve phosphorous， 6 strains had the ability to produce siderophores， and 4 strains had the ability to release potassium. These findings provide a theoretical basis and microbial resources for the exploitation of rhizosphere fungal resources of K. humilis and the development of microbial fertilizers in the source region of the Yellow River.

To elucidate the initial effects of nitrogen deposition on soil organic carbon （SOC） and its stability in alpine meadows， we conducted a field nitrogen addition experiment in the eastern Qilian Mountains. Aboveground biomass， soil physicochemical properties， enzyme activities， and SOC fractions were measured， and their key drivers were identified using variance partitioning. Nitrogen addition significantly increased aboveground biomass but reduced cellulase and β-glucosidase activities （P<0.05）. Particulate organic carbon （POC） content and proportion decreased markedly， whereas easily oxidizable organic carbon （EOC） and mineral-associated organic carbon （MAOC） increased significantly （P<0.05）. POC dynamics were mainly regulated by total phosphorus and carbon-acquiring enzymes， MAOC was closely associated with aboveground biomass， pH， and β-glucosidase， while EOC was primarily driven by available phosphorus and cellulase. Overall， microbial biomass carbon （17%） and dissolved organic carbon （14.1%） primarily explained short-term SOC variations. In summary， nitrogen addition enhanced soil carbon pool stability by promoting plant carbon inputs， modulating enzyme activities， and reshaping the distribution of SOC fractions. These findings reveal the pathways through which nitrogen deposition stabilizes SOC in alpine meadows， providing critical insights into carbon cycling processes and the carbon sequestration potential of fragile ecosystems under nitrogen enrichment.

In order to study the nitrogen and phosphorus homoeostasis of plant community of desert steppe under different stocking rates， the Stipa breviflora desert steppe in Inner Mongolia was used as the research object. The grazing experiment adopted a completely randomized block design， with a total of 4 levels of stocking rate and 3 repetitions， namely control （CK）， light grazing （LG）， moderate grazing （MG） and heavy grazing （HG） [sheep units·hm^-2·0.5a^-1]. The total nitrogen （TN） and the total phosphorus （TP） in plant community and soil were measured， and than calculated the homeostasis index （H）， the results showed that the interaction between grazing and soil layer had no significant effect on the soil. Grazing attenuated TN and TP homeostatic regulation of the plant community. When the stocking rate was <1.1 or> 3.65， TN homeostasis was weakly homeostatic. The TP homeostasis was enhanced in HG. When the stocking rate was <1.09 or> 2.78， TP homeostasis was weakly homeostatic. The N∶P homeostasis was the strongest in MG， and when the stocking rate ranged from 0.17 to 1.9， the N∶P homeostasis was weakly homeostatic. Overall， when the stocking rate ranged from 0.17 to 1.09， which is a light to moderate grazing level， the grassland ecosystem had homeostatic regulation. The stocking rate has a minimum threshold of 2.37 for H_TN and 1.94 for H_TP， while a maximum threshold of 1.03 exists for H_N∶P.

This study focued on alfalfa fields in the Loess hilly region as research objects， with four experimental treatments were established： no fertilization （CK）， nitrogen fertilizer alone （T1）， phosphorus fertilizer alone （T2）， and combined nitrogen-phosphorus fertilization （T3）. By examining the ecological stoichiometry of soil-microbe-extracellular enzyme systems under nitrogen and phosphorus addition， this research explored the characteristics of soil nutrient limitations and the feedback mechanisms of microbial communities to metabolic constraints. The results showed that fertilization significantly decreased soil carbon to phosphorus ratio， microbial biomass carbon to phosphorus ratio （MBC∶MBP）， microbial biomass nitrogen to phosphorus ratio （MBN∶MBP）， and enzymatic stoichiometric carbon to nitrogen ratio （EEA_C∶N）. In contrast， soil nutrient content， microbial biomass， extracellular enzyme activities， and enzymatic stoichiometric nitrogen to phosphorus ratio （EEA_N∶P） were significantly increased. Enzyme vector modeling and vector analysis indicated that long-term alfalfa cultivation led to varying degrees of carbon and phosphorus limitation in soil microorganisms. Nitrogen and phosphorus addition alleviated the microbial phosphorus limitation and increased microbial carbon use efficiency （CUE）. In conclusion， appropriate supplementation of nitrogen and phosphorus fertilizers is recommended for soils under long-term alfalfa cultivation in the Loess hill region， to mitigate nutrient limitations on soil microorganisms.

Saline-alkali land is widely distributed worldwide， and it is of great significance to screen for germplasm resources of saline-alkali resistant Bromus inermis for improving saline-alkali land In this study 100 Bromus inermis germplasm resources were selected as the reseat objects. During the seedling stage， 200 mmol·L^-1 NaHCO₃ solution was used for stress treatment， and 14 traits including plant height， root length， seedling fresh weight/dry weight， root fresh weight/dry weight were measured. Multiple statistical methods such as correlation analysis， principal component analysis， membership function analysis， and cluster analysis were used to comprehensively evaluate the alkali tolerance of different smooth brome germplasm resources. The results showed that there were varying degrees of variation in the alkali tolerance coefficients of 14 personality traits， ranging from 39.52% to 74.83%. Relative conductivity was negatively correlated with 13 indicators including plant height， root length， and seedling fresh weight. Using principal component analysis， 14 traits were classified into 3 components， with a cumulative contribution rate of 73.719%. Plant height， stem thickness， fresh weight of aboveground parts， dry weight of aboveground parts， survival rate， root surface area， root volume， and relative conductivity can be used as the main evaluation indicators for alkali tolerance at the seedling stage of smooth brome. Cluster analysis grouped 100 rootless barley seeds into three categories， including 16 alkali tolerant materials， 63 medium resistant materials， and 22 alkali sensitive materials. The results provide excellent germplasm materials for the screening of alkali tolerance indicators and the breeding of new varieties of smooth brome.

The North and Northwest regions of China are major oat-producing areas. However o persistent drought stress there leads to significant yield losses of oat production. The identification of drought-resistant germplasm resources is therefore a core strategy for achieving stable and even enhanced oat production in these regions. In this study， 99 oat germplasm accessions were evaluated under simulated drought conditions using a 10% PEG-6000 solution， with Hoagland’s solution serving as the control. A total of 16 growth traits—including both aboveground and root parameters—were systematically measured at the seedling stage. Drought resistance was comprehensively assessed through membership function analysis， principal component analysis， and linear regression modeling. The results revealed a general decline in all measured traits under drought stress， with aboveground dry weight， total root length， root tip number， and root fork number showing particularly high sensitivity. Based on the integrated evaluation， the 99 oat accessions were classified into three drought-resistance categories， and ten highly drought-tolerant lines—including ZYC-101， ZYC-38， and AM-124—were identified. This work not only provides a theoretical foundation for stress-resilient oat breeding but also establishes a practical framework for the large-scale screening and utilization of drought-tolerant germplasm resources.

To accelerate the breeding of salt-alkali-tolerant alfalfa （Medicago sativa L.） varieties， in this study 19 alfalfa germplasms were used to establish a seedling-stage screening system for identifying salt-alkali-tolerant materials. By combining generation breeding， salt-alkali-tolerant alfalfa germplasms were rapidly propagated to obtain the first generation hybrid （F1）， which were subsequently evaluated for salt-alkali tolerance. The results showed that two-week-old alfalfa seedlings treated with 0.1 mol·L^-1 Na⁺ （NaCl∶NaHCO₃=1∶1， pH=8.5） for 72 h could be effectively used to screen salt-alkali-tolerant individuals. Evaluation of 19 alfalfa germplasms at the seedling stage revealed that cultivars ‘WL-168HQ’ ‘Galaxie Max’ and ‘Bara416’ exhibited significantly higher salt-alkali tolerance than the others. By adjusting the light quality ratio， the FCL5 light condition （450-465 nm （white light） 66.67%， 450-480 nm （blue light） 6.67%， 615-650 nm （red light） 26.66%） was identified as optimal， which supported healthy growth and high induction efficiency. Under FCL5 condition， 110 elite salt-alkali-tolerant plants were subjected to flowering induction and open pollination to produce F1 half-sib family seeds. Evaluation of six F1 half-sib families demonstrated that the proportions of salt-alkali-tolerant plants in ‘Octane’‘Bara416’ and ‘ZN-CT25’ families were significantly higher than those of unselected commercial cultivars. This study provides technical support and valuable germplasm resources for the breeding of new salt-alkali-tolerant alfalfa varieties.

To comprehensively evaluate the differences in cadmium tolerance of different alfalfa （Medicago sativa L.） germplasms during seed germination， the indicators related to seed germination and seedling growth of 40 cultivars were measured under two conditions of control （distilled water） and cadmium stress （50 μmol·L^-1 CdCl₂） in this study. Based on the comprehensive indicator weight， membership function analysis and comprehensive evaluation value （D value）， the cadmium tolerance of the tested alfalfa germplasms was comprehensively analyzed. The results indicated that 50 μmol·L^-1 cadmium solution had inhibitory effects on nine indicators including seed vigor index， root length， and seedling vigor index of the tested alfalfa cultivars， with root length being the most inhibited. Based on the comprehensive evaluation of cadmium tolerance D value and systematic clustering analysis， the cadmium tolerance of 40 tested alfalfa germplasms was divided into three categories， namely strong cadmium tolerance （D≥0.691）， medium cadmium tolerance （0.691>D≥0.468） and weak cadmium tolerance （0.468>D）. The cultivars with the strongest and weakest cadmium tolerance were selected as ‘Bara520YQ’ and ‘WL298HQ’， respectively. This study provides a theoretical reference for screening and utilization of new germplasms of alfalfa with cadmium tolerance， the mining of cadmium tolerance genes， and the exploration of molecular regulatory mechanisms.

Grazing is a primary utilization method of grasslands， and determining the appropriate grazing intensity is of crucial for grassland conservation and the sustainable development of animal husbandry. A controlled grazing experiment was conducted during the warm season of 2023 at the 77th Regiment Horse Farm in Zhaosu County， four treatments were set up： no grazing， light grazing （1 horse·hm^-2）， heavy grazing （4 horse·hm^-2）， and extreme grazing （6 horse·hm^-2）， and a randomized block design was adopted. The effects of grazing intensity on pasture carrying capacity were evaluated by monitoring plant community structure， diversity， standing biomass， forage nutritional quality， and by calculating digestible energy （DE） and the grading index 2001 （GI₂₀₀₁）.The results indicated that light grazing maintained relatively a high species diversity， while the no-grazing area exhibited the best forage nutritional quality. The biomass carrying capacity was the highest under heavy grazing [0.73 horse·hm^-2·（122d）^-1]， and the crude protein yield carrying capacity was relatively high under extreme grazing [0.99 horse·hm^-2·（122d）^-1]. However， these conditions were accompanied by the decline of sedges and a surge in forbs， representing an unsustainable short-term phenomenon. The PLS-PM （Partial Least Squares Path Modeling） model showed a direct negative effect of grazing intensity on GI₂₀₀₁ and DE. In conclusion， light grazing （1 horse·hm^-2） is the suitable intensity for the Zhaosu mountain meadow steppe， effectively balancing ecological conservation and the needs for continuous grazing of Yili horses.

This study was conducted in the temperate steppe of Ningxia Luoshan Nature Reserve. The dominant plant species at different altitudes were selected as research objects： Carex aridula at 2374 m， Stipa grandis at 2132 m and 1823 m， and Stipa breviflora at 1566 m. Xylem water from the dominant plants， precipitation， and soil water from the 0-100 cm layer were collected. The stable hydrogen （δD） and oxygen （δ¹⁸O） isotopic compositions were determined. The MixSIAR mixing model was employed to quantitatively analyze the utilization ratios of plants to potential water sources. The results showed that： （1） Soil water δ¹⁸O exhibited significant spatial heterogeneity， generally decreasing with increasing altitude， with significantly lower isotopic values in soil water at high altitudes compared to low altitudes. （2） The water use patterns of dominant plants at different altitudes showed significant differences during the growing season （June-July）. Carex aridula at high altitude shifted its main water absorption source from the 40-60 cm soil layer （23.8%） in June to the 0–20 cm layer （26.9%） in July. Stipa grandis at mid-altitude changed from absorbing water from all soil layers （0-100 cm） with proportions ranging between 15.9% and 22.3% in June to concentrating water uptake in the 0-40 cm layer in July. Stipa breviflora at low altitude stably utilized water from the 0-20 cm shallow soil layer， with a utilization proportion between 27.8% and 32.4%. This study provides an important scientific basis for understanding the water use strategies of dominant species and the water balance in the Luoshan temperate steppe ecosystem.

This study aimed to assess the sustainability of alfalfa-grain maize rotations in central-northern Shanxi Province， China， and to screeen the optimal management strategies. The Agricultural Production System Simulator （APSIM） model was calibrated using multi-site experimental data and employed to simulate long-term historical （1985—2014） and future climate scenarios （2021—2050； 2051—2080）. Three rotation systems were compared： 6A （6-year continuous alfalfa）， 5A1C （5-year alfalfa+1-year grain maize）， and 4A2C （4-year alfalfa+2-year grain maize）. The results indicated that the model performed well in simulating yield and biomass （Normalized Root Mean Squared Error， NRMSE<20%）. Under future climate scenarios， the equivalent yield of 6A was significantly higher than that of 5A1C and 4A2C （P<0.05）， which were increased by 9.45% and 23.02% compared to 5A1C in the 2020s and 2050s， respectively and increased by 23.02% and 28.49% compared to 4A2C. Furthermore， 6A achieved the highest single-cycle equivalent yield （59.98 t/hm²） under the historical scenarios. Regarding precipitation matching， values exceeded 0.6 for maize and were >0.8 for alfalfa during May–August. However， the matching degree was lower in April， September， and October， indicating substantial irrigation requirements. The precipitation matching were significantly improved by future scenarios （P<0.05）， though the values of 6A remained lower than 4A2C during April and May. In conclusion， 6A maximized land productivity under future climates with enhanced irrigation in spring conversely. 4A2C offers a more balanced combination of productivity and water use efficiency. Our results could support the strategies of optimized forage and adaptive rotation strategy in Shanxi.

No-tillage reseeding is one of the important measures for improving degraded grasslands. This study focused on three types of temperate grasslands in the Ili River Basin of Xinjiang， setting up no-tillage reseeding and free grazing treatments. The aim was to investigate the effects of short-term reseeding treatment on plant communities， soil physicochemical properties， and plant-soil ecological stoichiometric characteristics， as well as to reveal the ecosystem’s internal stability response mechanisms. The results showed that no-tillage reseeding significantly increased aboveground biomass and community coverage， with community diversity significantly enhanced only in the temperate meadow steppe. The effects of no-tillage reseeding on soil physical properties varied across the grassland types. Plant carbon content significantly increased across all three grassland types， while nitrogen content significantly decreased， and the nitrogen-to-phosphorus ratio of vegetation significantly decreased. Soil organic carbon and total nitrogen both significantly increased， while total phosphorus showed no significant change. The soil carbon-to-phosphorus ratio in the temperate desert steppe and temperate grassland significantly increased， and nitrogen-to-phosphrous ratio increased significantly only in temperate desert steppe. Plant communities of all three grassland types exhibited “absolutely steady state” characteristics. In conclusion， no-tillage reseeding significantly enhanced grassland productivity by promoting community restoration and regulating soil nutrients. The responses of different grassland types to no-tillage reseeding vary， providing scientific evidence and theoretical support for the “differentiated zoning management” of grassland ecological restoration in arid and semi-arid regions.

In order to explore the response of sagebrush deserts grassland community structure and biomass component allocation pattern of Seriphidium borotalense to degradation under different degradation degrees， the plant community characteristics， plant community diversity index， species diversity characteristics， and modular biomass allocation patterns of S. borotalense desert grassland in undegraded （UD）， lightly degraded （LD）， moderately degraded （MD）， and highly degraded （HD） areas were measured and analyzed. It was found that with the increase of degradation degree， the community height， coverage and aboveground biomass decreased significantly， and the density increased significantly （P<0.05）. The Patrick index did not change， and the other diversity indexes decreased significantly. The height， coverage and aboveground biomass of S. borotalense decreased significantly （P<0.05）， and the density reached the maximum at LD， but no S. borotalense was found at HD. The distribution of stem and leaf components such as plant height， stem length and leaf weight decreased significantly （P<0.05）， and the distribution of root components such as root weight， root diameter and root weight ratio reached the maximum at LD. Redundancy analysis showed that community coverage was the most critical environmental factor driving the component allocation pattern of S. borotalensei. To sum up， S. borotalense responded to grassland degradation by optimizing the component allocation pattern， and the optimization threshold was between LD and MD.

To investigate the appropriate nitrogen addition concentration for synergistically restoring productivity and maintaining biodiversity in degraded alpine steppe， this study conducted a randomized block experiment in the northern Xizang alpine steppe （elevation 4634 m）. Six nitrogen addition gradients （0，5，10，15，20， and 25 g·m^-2·a^-1 N） were set under natural conditions and with phosphorus application. Mixed-effect models were used to analyze the effects of nitrogen addition on plant aboveground biomass， community structure， and diversity. The results showed that short-term nitrogen addition significantly increased plant aboveground biomass， with the promoting effect strengthening as nitrogen concentration increased. Simultaneously， nitrogen addition significantly reduced plant diversity， with the inhibitory effect intensifying with higher nitrogen concentrations， accompanied by an increase in the importance value of grasses and a decrease in the importance values of sedges and forbs. Phosphorus application enhanced the positive effect of nitrogen addition on aboveground biomass but did not significantly exacerbate the inhibition of plant diversity. This study reveals that moderate nitrogen addition （10~15 g·m^-2·yr^-1N） with phosphorus application may be an effective restoration measure for degraded alpine steppe， providing a scientific basis for the sustainable management of alpine steppe ecosystem.

The Enhanced Vegetation Index （EVI） is a key indicator for characterizing vegetation activity and understanding the processes of the terrestrial ecosystem carbon cycle. Investigating its response to climate change helps deepen the understanding of vegetation-climate interaction mechanisms. This study focused on the Yin Mountain region of Inner Mongolia. Utilizing MODIS EVI datasets and meteorological data from 2001 to 2021， and employing methods such as trend analysis， partial correlation analysis， multiple linear regression， and partial least squares structural equation modeling （PLS-SEM）， we analyzed the spatiotemporal patterns of vegetation EVI and climatic factors in the region， and revealed the influence mechanisms of wind speed， precipitation， temperature， and solar radiation on EVI changes. The results indicated that from 2001 onwards， the annual mean EVI in the study area showed a fluctuating yet significantly increasing trend， with a slope of 0.002 74 per year （P<0.01）. The EVI increased from 0.172 in 2001 to 0.256 in 2021， representing a growth rate of 48.8%. Spatially， EVI increased gradually from northwest to southeast， with most areas showing a significant increasing trend， and the highest slope （>0.012） was observed in the south. Regarding the influencing mechanisms， EVI in the western and southern parts was primarily driven by wind speed and in the east by radiation， while in the north， it was jointly influenced by precipitation， radiation， and temperature. This research provides valuable insights for formulating regional ecological restoration policies.

Taking the grassland in the upper reaches of the Yellow River Basin as the research object， based on multi-source data from 2000 to 2023， the degradation problem was analyzed from the dual perspectives of “grassland coverage type transformation + degradation evaluation index system”， and the CA-Markov model was used to predict the future degradation pattern. The results showed that： （1） The grassland is mainly composed of medium coverage grassland. Over the past 23 years， the total area of grassland has decreased by 2201.60 km²， and the coverage conversion has fluctuated greatly， showing obvious spatial differentiation characteristics. （2） The proportion of un-degradation grassland has decreased from 59.77% to 54.62%， showed an overall “one decrease and three increases” degradation feature. Spatially， it presented a pattern of “low in the southwest and high in the northeast”， and the area of regions with increased degradation grades was larger than that of regions with decreased grades. （3） By 2030， the proportion of un-degradation grassland will further decline， while the proportions of mild， moderate and severe degradation grassland will increase， and the degradation trend will continue to intensify. The research can provide a scientific basis for regional grassland protection and management.

To investigate the short-term effects of biogas slurry fertilizer on the physicochemical properties of degraded grassland soil， this study investigated moderately degraded grasslands in Zhenglan Banner， Xilingol League. Four treatments were established： blank control （CK）， water control （W₀）， 50% diluted concentration of biogas slurry fertiliser （BS_50%）， and full concentration of biogas slurry fertiliser （BS_100%）. The application rate was 300 m³·ha^-1. The contents of nitrogen （N）， phosphorus pentoxide （P₂O₅） and potassium oxide （K₂O） in the biogas slurry are 0.11%， 0.07% and 0.09% respectively. Soil samples from 0~15 cm and 15~30 cm soil layers were collected to analyze their physical and chemical property indexes. The results showed that compared with CK， both BS_50% and BS_100% treatments significantly improved soil physical structure， with decreasing soil bulk density and increasing soil porosity. Applying biogas slurry fertilizer markedly enhanced soil physical and chemical properties and microbial activity. The contents of soil total nitrogen， available phosphorus and available potassium increased significantly by 14.50%-25.86%， 66.87%-204.06% and 30.26%-193.91%， respectively， while the contents of soil microbial biomass carbon and microbial biomass nitrogen increased significantly by 11.04%-18.39% and 12.47%-28.34%， respectively. This study revealed the short-term effects of biogas slurry fertilizer on the physicochemical properties of degraded grassland soils. It provides fundamental scientific evidence for restoring degraded grasslands and enhancing soil fertility， while also offering reference support for the resource utilization of biogas slurry fertilizer and the sustainable management of grassland ecosystems.

Land-use change is a significant factor affecting biodiversity. To explore the effects of different land-use types on insect community structure and diversity in the agro-pastoral ecotone of the Bashang region， a study on insect species composition and community structure was conducted from July to September 2024 in fenced grassland （FG）， grazed grassland （GL）， and cropland （CL） in the Bashang region of Hebei Province. A total of 937 insect individuals were collected， representing 103 species belonging to 45 families and 6 orders. The study revealed that land-use type significantly affected insect community structure and diversity （P<0.05）. Among them， FG had the highest diversity， followed by GL， and CL had the lowest diversity. The community functional groups and dominant families varied significantly across different land-use types， with herbivorous insects being the predominant group in all habitats. Different functional groups responded differently to environmental conditions： predators preferred warm， low-vegetation， and resource-rich environments. Detritivores favored tall， dry environments with low biomass. And herbivores preferred moist environments with sparse vegetation. Correlation analysis revealed that soil temperature， plant species richness， and aboveground biomass were the key influencing factors （P<0.001）. Multivariate analysis showed significant differences in community composition among the different land-use types （R²=0.238， P<0.05）. In conclusion， land-use management regulates insect community structure and function by altering vegetation and soil conditions. This study provides a reference for land-use changes aimed at biodiversity conservation in the Bashang region.

To elucidate the multilevel drivers of stocking rate increase on plant community state transition in desert steppe， this study was performed in a long-term grazing manipulation platform （2004-present） in Stipa breviflora desert steppe of Inner Mongolia. Four grazing intensity treatments were established： no grazing （CK）， light grazing （LG，0.91 sheep units·hm^-2·half-year^-1）， moderate grazing （MG， 1.82 sheep units·hm^-2·half-year^-1）， and heavy grazing （HG， 2.71 sheep units·hm^-2·half-year^-1）. Based on data from 145 monitored quadrats in representative plots， a state transition probability matrix was constructed， integrating species interaction networks， functional group succession， and plant family closure analysis. The results showed that： （1） Plant population network complexity peaked during the stage of LG transition to MG （with only 4 isolated species）， whereas core species （e.g.， the disappearance of Teloxys aristata） reduced and isolated species sharply increased to 15 at the HG stage； （2） As stocking rate increased， the transition probabilities from shrub-subshrub （SS） and perennial forbs （PF） to perennial grasses （PG） rose， while the transition probability from PG to annual-biennial plants （AB） increased by more than 30% under HG； （3） The receiving capacity of the Poaceae （POA） strengthened with increasing stocking rate， whereas the biomass proportion of Asteraceae （AST） declined. In summary， a stocking rate exceeding 1.82 sheep units·hm^-2·half-year^-1 triggered the critical threshold for community degradation. In contrast， moderate grazing （LG-MG） maintained community stability through species redundancy， optimized resource allocation among functional groups， and the formation of closed-loop transitions between plant families. This study provides a multidimensional theoretical foundation for early warning of desert steppe degradation and targeted restoration.

Algal crusts represent a crucial type of biological soil crust in desert grasslands and serve as an important significant “ecological engineer”. They play a vital role in soil stabilization， water retention， wind erosion resistance， and carbon and nitrogen sequestration. However， researches on the effects of different grazing intensities on the characteristics of algal crusts in desert grasslands remains relatively limited. Based on a long-term grazing experiment platform （2004-present） in the desert grassland of Siziwang Banner， Inner Mongolia， in this study we investigated the impacts of varying grazing intensities on the algal crusts characteristics and identified the key driving factors. We measured the coverage， thickness， chlorophyll-a content of algal crusts， as well as related soil physicochemical properties under different grazing intensities. The results showed that as grazing intensity increased， the coverage， thickness， and chlorophyll-a content of algal crusts significantly decreased （P<0.05）. Structural equation modeling further revealed the key soil factors driving changes in algal crusts， among which soil available nitrogen was the most critical factor influencing characteristics of algal crusts. This study demonstrated that moderate and heavy grazing significantly inhibited the growth of algal crusts in desert grasslands， with soil bulk density， capillary water holding capacity， and soil available nitrogen were the most closely related factors to the changes in algal crusts characteristics. To maintain the ecological functions of algal crusts in desert grassland ecosystems， it is essential to strictly control grazing intensity， as long-term high-intensity grazing will lead to their severe degradation.

Grazing is a key human disturbance affecting the structure and function of desert steppe ecosystem. Most of the current studies focus on the response of species or functional groups at a single level， and there is a lack of systematic analysis of the changing patterns of the correlation between the two with the change of disturbance gradient. In this study， Stipa breviflora desert steppe in Inner Mongolia was taken as the object， and four stocking rate gradients were set up. By measuring the characteristics of plant populations and dividing functional groups， the relationship between dominant species （Stipa breviflora， Cleistogenes songorica， Artemisia frigida） and functional groups （life form， photosynthetic type， root type） was analyzed by grey correlation degree. The results showed that： （1） The dominant species had different responses to grazing. Stipa breviflora and Cleistogenes songorica had strong grazing tolerance， and Artemisia frigida decreased significantly with the increase of stocking rate. （2） Perennial grass （PG） was always dominant in the community， C₄ functional group performed the best under moderate grazing， and the axis root system （ARS） was sensitive to grazing. （3） Grazing intensity regulated the association pattern of dominant species and functional groups： the two were the most closely related under light grazing （LG）， the dominant species contributed the most under moderate grazing （MG）， and heavy grazing （HG） led to the weakening of functional group association and community simplification. This study revealed the dynamic response of dominant species and functional groups to grazing， and provided a scientific basis for grassland management in arid areas.

This study investigated the effects of lactic acid bacteria （LAB） and Amomum villosum Lour. stems and leaves （ASL） on the fermentation quality， nutritional composition， and bacterial diversity of King grass（Pennisetum purpureum×P. americanum） silage. Four treatments were established： CK （no additives）， ASL （30% ASL addition）， LAB （compound LAB inoculant at 5×10⁶CFU·g^-1 fresh weight）， and ASL-LAB （30% ASL+LAB）， each with three replicates. Samples were collected and analyzed after 56 days of ensiling. Results showed that， compared to CK， the pH and ammonia nitrogen （NH₃-N） content were significantly decreased （P<0.05） in the ASL， LAB， and ASL-LAB groups， while lactic acid （LA） content significantly increased （P<0.05）. Dry matter （DM） and crude protein （CP） content in the CK group were significantly lower than those in the other treatments （P<0.05）. The relative abundance of Lactiplantibacillus increased by 12.17%， 37.58%， and 57.19% in the ASL， LAB， and ASL-LAB groups， respectively. Conversely， the relative abundance of Unclassified Enterobacteriaceae decreased by 3.91%， 28.82%， and 30.27% in these groups. Correlation analysis indicated that Lactiplantibacillus was negatively correlated with Enterobacter， Unclassified Enterobacteriaceae， and NH₃-N（P<0.05）， but positively correlated with LA and CP （P<0.05）. In conclusion， while supplementation with LAB inoculant or ASL alone improved fermentation quality and mitigated nutrient loss in King grass silage， the combined application of ASL and LAB yielded the most pronounced improvements.

The purpose of this study was to investigate the effects of different additives on the fermentation characteristics and microbial community of mulberry leaf silage. In this experiment， fresh mulberry leaves were served as raw materials， and six treatment groups were established， including control group （CK）， Pediococcus pentosaceus group （SSW）， Lactobacillus plantarum group （SSZ）， cellulase group （SSX）， Pediococcus pentosaceus+cellulase group （SSWX）， and Lactobacillus plantarum+cellulase group （SSZX）. Nutritional indicators， fermentation quality， and microbial diversity were assessed during a 45-day silage process at room temperature. The results revealed that the SSZX group exhibited the highest crude protein content （18.81% DM） and significantly reduced levels of neutral detergent fiber （NDF） and acid detergent fiber （ADF） （26.00% DM and 22.00% DM， respectively） （P<0.05）. Regarding fermentation characteristics， the additives markedly enhanced fermentation quality. The SSZX group recorded the lowest pH value （4.29）， the highest lactic acid content （39.90 g·kg^-1）， and the lowest ammonia nitrogen （AN） content （4.97 g·kg^-1）， without being detected butyric acid. In terms of microbial composition， the CK group was predominantly composed of Enterobacter （40.00%） and Fusarium （20.00%）， indicating a risk of spoilage. In contrast， Lactobacillus plantarum was the dominant bacterium in the SSZ and SSZX groups， comprising 75.00% to 84.00% of the microbial population. The abundance of Lactobacillus plantarum was significantly negatively correlated with both pH and NDF， thereby confirming its inhibitory effect on harmful microorganisms. In conclusion， the addition of Lactobacillus plantarum and cellulase to mulberry leaf silage had the highest quality.

The experiment was designed to investigate the effects of the composite bacterial agent composed of Lactobacillus plantarum， Bacillus subtilis and Aspergillus niger and its compounding with molasses or cellulase on the silage quality and microbial diversity of corn straw. A single-factor randomized design was adopted with four treatments： control group （CK）， composite fungicide group （BC）， composite fungus with molasses group （FT）， and composite fungus with cellulase group （FX）. Each group was replicated three times， and after 30-day fermentation at room temperature， the samples were opened and sampled to determine their nutrient composition， fermentation quality and microbial diversity. The results showed that compared with the CK group， the crude protein （CP） and crude ash （Ash） contents in BC， FT and FX groups increased significantly， while the neutral detergent fiber （NDF） and acid detergent fiber （ADF） contents decreased significantly. The FX group had the highest contents of ammonia nitrogen （NH₃-N， 9.13%DM） and acetic acid （AA， 1.95%DM）. The Entropy Weight-TOPSIS evaluation indicated that the FX group had the best quality with a relative closeness degree （C_i） of 0.510. Microbial diversity analysis showed that BC， FT and FX groups significantly reduced community richness and diversity. At the phylum level， the dominant phylum in all groups was Bacillota， with the highest relative abundance in the FX group， followed by Pseudomonadota with the highest abundance in the CK group. At the genus level， the dominant genera in the CK group were mainly Lentilactobacillus， Sporolactobacillus， Clostridium， and Lactiplantibacillus， while the BC， FT and FX groups were dominated by Lentilactobacillus. In conclusion， the composite bacterial agent significantly improved the silage quality of corn stover and altered its microbial community structure， with the FX group （bacteria enzyme synergism） showing the best silage effect.

To screen plant growth-promoting rhizobacteria （PGPR） that are capable of stably colonizing the rhizosphere of Stipa purpurea， four PGPR strains previously isolated from this alpine grass were evaluated. Rifampicin-resistant derivatives were generated to monitor root-zone colonization dynamics， and the effects of bacterial inoculation on seed germination， seedling morphology， and physiological indices were assessed under the culture of 15℃， 20℃， and 25℃. Serratia proteamaculans GD-1-1 and Paenarthrobacter nitroguajacolicus YD-2-4 established stable populations in the S. purpurea rhizosphere， and the colonization amounts were 1.22×10⁸ and 0.06×10⁸ CFU·g^-1 at 20 d， respectively. Dilutions of YD-2-4 （1×10¹ and 1×10² CFU·mL^-1） significantly enhanced germination and seedling growth across 15℃-25℃， concurrently increasing antioxidant enzyme activities and lowering malondialdehyde content. In contrast， the stimulatory effect of GD-1-1 （1×10² and 1×10³ CFU·mL^-1） declined with temperature and disappeared at 15℃. These results indicated that YD-2-4 possessed robust colonization ability and broad temperature adaptability， making it an excellent candidate for the development of microbial inoculants for alpine grasslands.

In order to alleviate the pressure caused by the shortage of forage grass in the alpine region of Xizang， Elymus nutans ‘Baqing’ was used as the research object in this experiment. A two-factor split-plot design was used. The main plot was the amount of nitrogen fertilizer added， and the sub-plot was the sowing rate. The amount of nitrogen fertilizer added was N₁ 0 kg·hm^-2， N₂ 60 kg·hm^-2， N₃ 120 kg·hm^-2， N₄ 180 kg·hm^-2， N₅ 240 kg·hm^-2 and N₆ 300 kg·hm^-2. The sowing rate was D₁ 15.0 kg·hm^-2， D₂ 22.5 kg·hm^-2 and D₃ 45 kg·hm^-2， so as to screen out the optimal planting configuration combination of ‘Baqing’ forage production. The results showed that under the same sowing rate， with the increase of nitrogen application rate， the production performance and nutritional quality of ‘Baqing’ were increased to varying degrees. Under the same nitrogen application rate， with the increase of sowing rate， the production performance and nutritional quality of ‘Baqing’ showed a trend of increasing first and then decreasing. Principal component analysis showed that 240 kg·hm^-2 nitrogen application rate and 22.5 kg·hm^-2 sowing rate were the optimal planting configuration for the production of ‘Baqing’. The above optimal planting configuration has certain theoretical reference value and production guiding significance for the promotion and utilization of ‘Baqing’ in the alpine region of Lhasa， Xizang.