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.

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.

Setaria viridis （L.） P. Beauv， a widely adaptable herbaceous plant distributed throughout China， possesses significant ecological and forage value. Due to its notable stress tolerance and its role as an important model plant， Setaria viridis has attracted wide interest in recent years. This article reviews research findings on the biological characteristics， genetic diversity， ecological value， and cultivar development of Setaria viridis， and offers perspectives for further research. It will provide theoretical references for the development， utilization， and breeding of new Setaria viridis varieties.

Salt stress leads to the accumulation of reactive oxygen species （ROS） in plants， causing damage to plant cells. However， the enzymatic antioxidant system is responsible for scavenging ROS in plant cells and protecting cells from ROS damage. At present， there are few functional analyses of genes related to ROS-scavenging enzymes in alfalfa （Medicago sativa） in response to salt stress. Based on the transcriptome data of roots and leaves of salt-tolerant alfalfa cultivar （GIB） and salt-sensitive cultivar （LS） under salt stress， this study identified 28 differentially expressed genes related to ROS-scavenging. Twenty-eight genes are distributed on 19 chromosomes， belonging to five gene families： MsGST， MsPOD， MsAOX， MsGRX and MsPrdx， among which MsGST （12） and MsPOD （11） families account for the largest proportion. The physicochemical properties of ROS scavenging enzyme proteins were different among the members of each gene family. There were highly similar conserved motifs in the members of the gene family. Phylogenetic analysis showed that MsGSTUs and MsPODs were located in the branches defined by Tau and AtPERs in Arabidopsis thaliana， respectively， suggesting that they had similar evolutionary processes and similar functions.Real-time fluorescence quantitative PCR analysis showed that the expression levels of MsGSTU26， MsPOD2 and MsPOD4 genes in GIB leaves under salt stress were significantly higher than those in LS， and the promoter regions of the three genes had elements （G-box and CGTCA-motif） related to adverse stress. It indicated that the MsGSTU26， MsPOD2 and MsPOD4 genes may be involved in the regulation of the adaptability of GIB and LS to salt stress.

Against the backdrop of China’s “dual-carbon” strategy and the advancement of ecological civilization， scientific assessment of the ecosystem service values and the realization of ecological product value have becomeacritical approach to harmonize ecological protection and economic development. As the dominant type of grassland ecosystem in China， temperate grasslands play crucial roles in carbon sequestration， water conservation， wind erosion control， and biodiversity maintenance. This article systematically reviews the research progress and methodological framework in economic valuation of temperate grassland ecosystem services， both in China and internationally. The applicability and limitations of major models were compared， and deficiencies in current Chinese research regarding data precision， parameter localization， service coverage， and policy integration were analyzed. This review proposes that future research should focus on constructing multi-scale integrated assessment frameworks， improving model localization and data sharing mechanisms， and strengthening the integration between assessment results and policies such as ecological compensation， GEP accounting， carbon trading， etc.， thereby forming the closed-loop mechanism of “Assessment-Accounting-Compensation-Feedback”. This study aims to provide theoretical foundation and decision support for valuing temperate grassland ecosystem services and realizing the value of ecological products.

Smart prataculture represents a vital component of modern agriculture and serves as a key strategy for promoting sustainable agricultural development and advancing the initiative “Big Food View” in China. As global challenges such as climate change and land degradation intensify， traditional grassland management models are increasing unable to meet the requirements of modernization. The integration of artificial intelligence （AI） technologies presents unprecedented opportunities for the advancement of prataculture， greatly enhancing the efficiency， precision， and intelligence of grassland management. AI-driven smart prataculture employs cutting-edge technologies such as machine learning， deep learning， big data analytics， and the Internet of Things （loT）. Through comprehensive data collection and analysis， these technologies enable real-time monitoring， precise prediction， and adaptive management of grassland growth， resource allocation， and livestock production. While the application of AI demonstrates substantial potential in optimizing grassland productivity， ecological restoration， and livestock health monitoring， significant challenges remain in data collection， technological dissemination， infrastructure development， talent cultivation， economic feasibility， and policy support. In the future， continued innovation in AI technologies and the integration of interdisciplinary approaches are expected to accelerate the intelligent transformation of prataculture in China. This evolution will promote comprehensive intelligence， precision， and transparency across the entire industry chain， from production and ecological protection to resource utilization and market systems， thereby providing new insights for the sustainable development of smart agriculture.

Nitrogenase is the key enzyme driving the natural nitrogen cycle， as it catalyzes the conversion of inert dinitrogen （N₂） into bioavailable ammonia （NH₃）. The most extensively studied nitrogenases， molybdenum nitrogenase （Mo-nitrogenase） and vanadium nitrogenase （V-nitrogenase）， differ significantly in their structure， catalytic properties， and environmental responses. Structurally， V-nitrogenase contains a unique δ subunit and has distinct encoding genes compared to Mo-nitrogenase. For catalytic mechanisms， Mo-nitrogenase exhibits higher specificity for N₂ reduction， whereas V-nitrogenase demonstrates broader substrate range and reduces alternative substrates such as acetylene. Furthermore， the two enzymes exhibit different sensitivity to carbon monoxide （CO）： Mo-nitrogenase is easily inhibited by CO， while V-nitrogenase can reduce CO even under high concentrations. These differences shape their functional performance in diverse environments. By systematically illustrating the structural， catalytic， and environmental differences between these nitrogenases， this study deepens the understanding of dynamic biological nitrogen fixation. The findings provide a critical theoretical basis for optimizing nitrogen management in grassland agriculture and offer guidance for the restoration of degraded ecosystems， such as grasslands， forests， and deserts.

Silage is a critical component of livestock diets in China and worldwide due to its high nutritional value and palatability. However， silage is highly susceptible to contamination by harmful fungi， leading to reduced quality， resource loss， and potential risks to both animal and human health during feeding. This review summarizes current knowledge on the major harmful fungi associated with silage and outlines corresponding control strategies. The objective is to enhance silage quality， safeguard feed safety， and support the sustainable， green， and high-quality development of the livestock industry.

Overgrazing will destroy grassland， aggravate vegetation degradation， and induce soil wind erosion. In this study， wind erosion monitoring was conducted on Stipabreviflora desert steppe under different grazing intensity （CK: control， LG: light grazing， MG: moderate grazing， HG: heavy grazing）. Plant community coverage was also measured to explore the patterns of aeolian sediment flux at sand collection height of 0-120 cm aboveground and its relationship with vegetation under different grazing intensities. The results showed that during the growing season of Stipa breviflora desert steppe： (1) Under different grazing intensities， the plant community coverage from May to October demonstrated the pattern of CK>LG>MG>HG. Under the same grazing intensity， it initially increased then decreased. (2) With the increase of grazing intensity， the total aeolian sediment flux rose gradually， with the value under LG， MG and HG reaching 1.40， 1.82， and 1.95 times of that under CK， respectively. (3) There was a significant negative correlation between plant community coverage and total aeolian sediment flux across all grazing intensities （P<0.05）. (4) The functional relationship among grazing intensity （G）， plant community coverage （C）， and total aeolian sediment flux （Q） was constructed： Q=（0.003 5G²－0.020 2G－0.032 7） C+（-0.251 2G²+1.478G+2.463 6）. The goodness of fit （R²） of plant community coverage and total aeolian sediment flux in CK， LG and MG was greater than 0.9， indicating high goodness-of-fit， while R² of HG was only 0.54， which offers a more integrated solution by striking a viable balance between aeolian sediment flux reduction and herder livelihood needs.Despite ideal windbreak and sand fixation performance of the CK and LG treatments， the MG treatment integrated the requirement of grassland ecosystem multifunctional role on aeolian sediment flux bloking and livelihood needs of herdsmen. This finding provides a scientific basis for exploring ecological protection and resource utilization in desert steppe， and has important practical value for establishing a sustainable and coordinated human-land grassland management framework.

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.

Fertilization is a key strategy for restoring degraded grasslands. To identify suitable nitrogen （N） and phosphorus （P） fertilization gradients for enhancing the productivity and soil characteristics of degraded alpine meadows， a lightly degraded alpine meadow in Dangxiong County， Xizang Autonomous Region， was selected for study. A two-factor randomized block design was employed， with four nitrogen levels （N0：0 kg N/hm²， N1：60 kg N/hm²， N2：90 kg N/hm²， N3：120 kg N/hm²） and four phosphorus levels （P0：0 kg P₂O₅/hm²， P1：30 kg P₂O₅/hm²， P2：60 kg P₂O₅/hm²， P3：90 kg P₂O₅/hm²）， resulting in 16 N-P treatments combinations， with N0P0 treatment serving as the control （CK）. Grassland productivity and soil characteristics were evaluated to determine the optimal N-P combinations. The results showed that the combined application of nitrogen and phosphorus fertilizers significantly enhanced aboveground biomass compared with the control， with the N2P2 and N2P3 treatments increasing biomass by 136.9% and 111.9%， respectively （P<0.05）. The combined application also improved soil organic carbon content， particularly in the 0-10 cm soil layer， where the N2P1 and N2P3 treatments reached 15.67 g/kg and 15.26 g/kg， respectively. Available phosphorus content was highest under N2P3 treatment in both 0-10 cm and 10-20 cm soil layers， while total nitrogen content was greatest under N3P1 treatment. Grey correlation analysis of aboveground biomass and soil characteristics （0-10 cm） indicated that N2P3 treatment provided the most favorable comprehensive improvement in productivity and soil nutrient status， followed by N3P3 treatment. Therefore， the combination of 90-120 kg/hm² nitrogen fertilizer with 90 kg/hm² phosphorus fertilizer is recommended as the optimal strategy for the restoration of degraded alpine meadows in Dangxiong County， Xizang Autonomous Region.

To clarify the impact of wind turbines on biodiversity and soil properties of grasslands， this study took a wind power area with wind turbines installed and operated for 15 years in the temperate meadow steppe of Inner Mongolia as the research area， and selected a grassland without wind turbines as the control area. The plant community， insect community， soil microorganisms， and soil physical and chemical properties in the area were investigated， and the relationships among these factors were analyzed. The results showed that compared with the grassland in the control area， the vegetation coverage， aboveground biomass， and community diversity of the grassland in the wind power area decreased significantly （P<0.05）. The number of insects in the wind power area increased significantly （P<0.05）， but the diversity of the insect community decreased significantly （P<0.05）. The number of soil fungi and community diversity in the wind power area were all significantly reduced （P<0.05）.Soil moisture content， bulk density， total nitrogen， ammonium nitrogen， alkali-hydrolyzable nitrogen， total phosphorus， and total potassium in the wind power area were all significantly reduced （P<0.05）. Correlation analysis found that there was a significant relationship between soil physicochemical properties and soil microbial communities. Overall， during the operation period of wind power stations， it will cause the degradation of grassland plant communities， the loss of soil nutrients and reduce plant diversity， and lead to a homogenization of the insect community structure.

Ecosystem services （ES） and ecological risk （ER） respectively represent the capacity of ecosystems to support human well-being and the potential for degradation under external disturbances. In recent years， the cumulative impacts of glacier retreat， permafrost degradation， and grassland deterioration have led to a decline in ES and an increase in ER on the Qinghai-Xizang Plateau. Therefore， exploring the coupling relationship between ES and ER on the Plateau is of great importance for accurately identifying ecological degradation processes， improving regional ecological resilience， and supporting effective environmental management. Based on remote sensing and statistical data from 2000 to 2020， this study evaluated important ES indicators and constructed an ER assessment framework using the InVEST model and landscape ecological risk assessment methods. The results showed that： （1） From 2000 to 2020， mean annual grassland productivity increased from 91.63 g/m² to 107.52 g/m²， while carbon storage declined from 6 571.73 Mg to 5 897.60 Mg. Water yield decreased from 122.10 mm to 86.55 mm in 2015 and rebounded to 110.71 mm in 2020. Habitat quality declined from 0.51 to 0.45， and soil conservation showed periodic fluctuations， ranging between 33 391.59 g/m² and 25 772.08 g/m². （2） The overall ER level showed a slight decline， but high-risk areas still accounted for over 19%， primarily concentrated in ecologically fragile zones such as Kekexili， the Qiangtang Plateau， and the Qaidam Basin. （3） Correlation analysis revealed significant negative correlations between ER and both grassland productivity （R² = -0.66， P < 0.05） and habitat quality （R² = -0.73， P < 0.05）. Carbon storage， water yield， and soil conservation also exhibited moderate negative correlations， suggesting that ER exerts an overall inhibitory effect on ES.

In order to explore potassium-solubilizing microbial resources and investigate their effects on alfalfa （Medicago sativa） growth， this study isolated and screened potassium-solubilizing bacteria （KSB） with strong potassium-solubilizing ability from the rhizosphere soil of alfalfa using selective media. The potassium-solubilizing， phosphate-solubilizing， and indole-3-acetic acid （IAA）-producing capabilities of these strains were measured， and their identities were confirmed via 16S rRNA gene sequencing. Subsequently， pot experiments were conducted using the selected superior strains to validate their impact on alfalfa growth. The results demonstrated that 21 KSB strains were isolated and screened from the alfalfa rhizosphere， among which 10 exhibited potassium-solubilizing activity， with solubilized potassium levels ranging from 1.57 to 7.96 μg/mL and solubilization rates ranging from 12.07% to 57.50%. Five strains （jk6-5、jk20-1、jk20-2、jk20-3 and jk20-8） with high potassium-solubilizing activity also demonstrated IAA production and phosphate-solubilizing abilities. Their IAA secretion levels ranged from 9.60 to 11.77 μg/mL， while inorganic phosphate solubilization ranged from 2.84 to 173.96 μg/mL， and organic phosphate solubilization from 35.34 to 62.55 μg/mL. Based on 16S rRNA gene sequencing， strains jk20-8， jk20-1， and jk20-2 were identified as Pantoea ananatis， strain jk20-3 belonged to the Paenibacillus hordei group， and strain jk6-5 was identified as Priestia megaterium. Inoculation of the superior strains jk20-8， jk20-3， and jk6-5 into alfalfa significantly increased plant height， root length， aboveground biomass， underground biomass， and nitrogen （N）， potassium（K）， and phosphorus （P） contents in plants. Additionally， soil available N， available P， available K， and organic matter contents were enhanced， with strain jk20-8 exhibiting the most pronounced growth-promoting effects. In conclusion， the potassium-solubilizing strain jk20-8 serves as a promising candidate for developing potassium-solubilizing microbial fertilizers.

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.

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.

To investigate the growth adaptability of ten forage oat （Avena sativa L.） varieties in continuous alfalfa replanting fields in the northeastern Ordos and to identify high-quality varieties suitable for multiple cropping， ten representative forage oat varieties were selected based on preliminary screening. A randomized block design was employed to analyze and compare their growth period， agronomic performance， and nutritional quality. Partial least squares path model （PLS-PM） was further applied to examine the effects of varieties and harvest date on agronomic traits and forage quality， while the grey relational analysis method was used for comprehensive evaluation. The results showed that varieties reached the milk stage in approximately 70-80 days in the northeastern region of Ordos. Among varieties， ‘Sun God’ and ‘Yellow Oat’ exhibited significantly greater plant height （121.44 cm and 114.31 cm， respectively； P<0.05）. ‘White Oat No.7’ produced the highest hay yield （9414.79 kg/hm²）， followed by ‘Yellow Oat’ （9130.31 kg/hm²）， both significantly exceeding other varieties （P<0.05）. ‘Aiwo 256’ had the highest crude protein （CP） content （12.14% DM）， significantly higher than ‘Qingyin No.1’ and ‘Leader （Surui）’ （P<0.05）. ‘White Oat No.7’ showed significant lower acid detergent fiber （ADF） and neutral detergent fiber （NDF） contents than most varieties， except ‘Qinghai 444’ and ‘Qingyin No. 2’ （P<0.05）. Except for ‘Qingyin 2’，the potassium （K） content of ‘White Oat No.7’ was significantly lower than that of all other varieties， while its relative forage quality （RFQ） was significantly higher than those of other varieties （P<0.05）. Across harvest dates， oats harvested on September 9th exhibited significantly greater plant height， hay yield， dry-to-fresh ratio， and RFQ， while CP， ADF， and K content were significantly lower compared to earlier harvests （P<0.05）. In contrast， oats harvested on August 21st had higher CP， ADF and K contents but lower plant height， hay yield， dry-to-fresh ratio， and RFQ. Grey relational analysis identified CP， NDF， and hay yield as key indicators for evaluating forage oat productivity. Overall， ‘White Oat No.7’ and ‘Yellow Oat’ demonstrated superior performance and were recommended for re-cultivation after alfalfa cutting in the northeastern Ordos.

This study investigated the efficacy of exogenous 2，4-epibrassinolide （2，4-EBR） in mitigating saline-alkali stress during seed germination and seedling growth of quinoa （Chenopodium quinoa Willd.‘Longli 1’）. Seeds were treated with various concentrations （0， 0.05， 0.1， 0.2， 0.4， 0.8， 1.5 and 2 mg/L） of 2，4-EBR and exposed to a range of simulated saline-alkali stress conditions. Principal component analysis and membership function method were used to comprehensively evaluate the physiological and biochemical indicators of quinoa under different saline-alkali stresses and different 2，4-EBR treatments. The results demonstrated that both single salt stress and mixed saline-alkali stress significantly inhibited the germination of quinoa seeds and the growth of seedlings. Exogenous application of 2，4-epibrassinolide （2，4-EBR） at concentrations of 0.05-2 mg/L effectively enhanced quinoa's osmotic adjustment capacity， alleviated oxidative damage induced by saline-alkali stress， and thereby improved its saline-alkali tolerance. Additionally， comprehensive evaluation analysis indicated that 0.2 mg/L 2，4-EBR exhibited the optimal alleviating effect on mixed saline-alkali stress； 0.4 mg/L 2，4-EBR proved the most effective for single salt stresses （NaCl and NaHCO₃）； and 0.8 mg/L 2，4-EBR was optimal for single salt stresses induced by Na₂SO₄ and Na₂CO₃.

Heat shock transcription factors （HSFs） play crucial roles in plant growth and development， as well as in responses to biotic and abiotic stresses. In this study， we identified the MruHSF gene family in Medicago ruthenica using genomic data and conducted bioinformatic analyses. The expression patterns of MruHSF gene under drought stress were comprehensively analyzed through transcriptomic data and quantitative real-time PCR （qRT-PCR）， preliminarily exploring their potential roles in drought stress responses. The results showed that 27 MruHSF family members， with encoded proteins ranging from 97 to 505 amino acids （aa）， isoelectric points （pI） between 4.64 and 8.72， and molecular weights of 10 998.3 to 55 296.45 Da. Except for three unassigned gene， the remaining MruHSF genes were distributed across eight chromosomes. Phylogenetic analysis classified them into three evolutionary clades. Conserved motif analysis revealed that all MruHSF proteins except MruHSF02， MruHSF03， and MruHSF27 contained Motifs 1， 2， and 4， which were highly conserved in M. ruthenica HSF protein. Additionally， multiple cis-acting elements related to hormone response， light response， and abiotic stress were identified in the promoter regions of MruHSF genes. Expression analysis shows that MruHSF01， MruHSF08， MruHSF13， MruHSF16， and MruHSF22 exhibited significant differential expression under drought stress， suggesting their potential roles in the drought response mechanism of M. ruthenica.

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.

This study investigated the effects of companion crops on forage growth and soil physicochemical properties during the first year of establishing a perennial alpine mixed grassland （Elymus breviaristatus ‘Tongde’ and Puccinellia tenuiflora ‘Tongde’） on the Qinghai-Xizang Plateau. The impacts of Brassica napus， Vicia faba， and Avena sativa at sowing rates of 10%， 30%， and 50% of their respective monoculture amounts were assessed. Aboveground biomass， belowground biomass， forage nutritional quality， and soil physicochemical properties were measured. The results showed that companion crops significantly improved forage productivity， nutritive value， soil moisture， and nutrients availability compared with the control. The 50% Vicia faba treatment yield the greatest benefits， significantly enhancing aboveground biomass （321.83%）， belowground biomass （56.29%）， crude protein （132.22%）， ether extract （52.75%）， and relative feeding value （126.80%）， as well as soil moisture （14.35%）， total nitrogen （57.58%）， ammonium nitrogen （301.49%）， and nitrate nitrogen （185.00%）. Structural equation modeling indicated that soil nitrogen and phosphorus contents were the primary drivers of forage biomass， nutritional quality， and soil physicochemical properties. A comprehensive Technique for Order Preference by Similarity to an Ideal Solution （TOPSIS） evaluation further identified the 50% Vicia faba treatment as the optimal companion crop strategy for establishing perennial alpine mixed grasslands on the Qinghai-Xizang Plateau.

This study aimed to explore the impacts of salt stress on the photosynthetic characteristics and sugar metabolism of Astragalus cicer seedlings. A. cicer cultivar ‘Gan Green No. 2’ was treated by 120 mmol/L NaCl solution as salt stress simulation. Sampling was conducted at 0， 1， 3， 5， 7， 14， and 21 days after stress applied for relevant indices measurement. The results indicated that salt stress induced stomatal closure in the leaves of A. cicer seedlings resulting in reduced stomatal conductance reduction and impairment of the photosynthetic system. Simultaneously， the chlorophyll content， net photosynthesis rate， transpiration rate， actual photochemical efficiency， apparent photosynthetic electron transport rate （ETR）， and photochemical quenching coefficient were significantly decreased. However， the contents of sucrose， fructose， and glucose exhibited trends of increasing initially followed by declining. Moreover， the intercellular CO₂ concentration， non-photochemical quenching coefficient （NPQ）， starch content， sucrose synthase （SS） activity， and activities of soluble acid invertase （SAI） and neutral invertase （NI） increased and eventually stabilized with treatment time prolonged. In contrast， the sucrose phosphate synthase activity （SPS） gradually exhibited a decreasing trend. Correlation analysis demonstrated that soluble sugars content were closely related to photosynthetic parameters， suggesting that sugars may play a crucial role in regulating of photosynthesis and plant light use efficiency. Starch content was positively correlated with NPQ， indicating that starch may be involved in regulating photoprotection and energy dissipation. In conclusion， salt stress tolerance of A. cicer seedlings can be enhanced by regulating sugar metabolism-related enzyme activities and photosynthetic system， leading to increased soluble sugar and NPQ levels. The findings of this study provide valuable insights into the growth and physiological mechanisms of A. cicer in saline-alkaline soils.

Grassland ecosystems have undergone severe degradation and shrub encroachment due to climatic drought and overgrazing. Water availability is the principal limiting factor regulating vegetation dynamics in these grassland ecosystems， with precipitation acting as the dominant water input that directly governs the spatiotemporal dynamics of soil moisture. Grazing， the main land-use practice in grasslands， interacts with precipitation to influence soil moisture dynamics and vertical distribution， thereby shaping competition between species with contrasting root architectures （e.g.， shrubs vs. grasses） and ultimately affecting ecosystem stability. This study reviewed the differential responses of upper and lower soil layers to precipitation during growing and non-growing seasons， and examined the combined impacts of overgrazing and precipitation on vertical soil moisture dynamics. The results showed that growing-season precipitation primarily enhanced soil moisture in the upper 0-30 cm， with limited effects on deeper layer （> 30 cm）. In contrast， non-growing-season precipitation increased post-thaw soil moisture in upper or lower layers， though findings varied regionally. Overgrazing significantly decreased soil moisture in the 0-30 cm layer during both growing and non-growing seasons， while its influence below 30 cm remained inconsistent. Compared with the growing season， non-growing-season precipitation regulated by freeze-thaw processes exhibited more complex effects on soil moisture vertical dynamics， yet remained poorly understood. Future studies should prioritize： （1） elucidating the mechanisms by which non-growing-season precipitation affects soil moisture distribution across diverse grassland ecosystems； （2） analysing grazing-precipitation interactions on vertical soil moisture variation， especially below 30 cm during the non-growing season. Advancing knowledge will provide a theoretical basis for understanding shrub encroachment mechanisms and for improving the management of soil hydro-ecological processes in grasslands.

This study focused on the moderately degraded alpine meadow in the eastern part of Qilian Mountains. A gradient of microbial fertilizer application rate was applied， namely CK （no microbial fertilizer）， BIM （7.5 g/m²）， BIIM （15 g/m²）， and BIIIM （22.5 g/m²）. The effects of different microbial fertilizer application rates on soil nutrient content， microbial community structure， and diversity of degraded alpine meadow were investigated. The results show that： In 0-10 cm soil layer， the soil nutrient content with microbial fertilizer application was significantly increased （P<0.05） compared with CK， with BIIM treatment showing the greatest effect. The contents of organic matter， available phosphorus， alkali hydrolyzable nitrogen， and available potassium were increased by 6.6%， 30.52%， 18.79% and 12.02%， respectively compared with CK； With the increase of soil depth， the effect of microbial fertilizer on soil nutrient content gradually declined； At the 20-30 cm depth， except for available potassium， no significant differences were observed among the treatments for any nutrients. The analysis of soil microbial community composition and diversity indicated that the effect of any bacterial fertilizer treatment on the diversity of fungal community was not significant， whereas the species richness of the bacterial community was significantly reduced by the BIIM treatment （P<0.05）. From the compositional perspective， the functional composition of microbial community was positively influenced by increasing the relative abundance of beneficial bacteria such as Penicillium， Mortierella， Bacillus， and Ferribacterium. Correlation analysis showed that the relative abundance of most beneficial bacteria was positively correlated with soil nutrient content. The results demonstrated that the application rate of 15 g/m² for the microbial fertilizer enriched with Bacillus subtilis， Bacillus mojavensis and Pseudomonas synxantha was effective. It significantly increased the content of key nutrients in soil and improved the soil microbial community structure， which could be applied in the restoration of regional degraded alpine meadow.

This study investigated the spatiotemporal dynamics of harvesting activities in Dongting Lake （South China） and their effects on Miscanthus lutarioriparius using multi-source satellite remote sensing data from 2015 to 2023. An object-oriented classification approach was applied to extract spatial distribution patterns based on vegetation spectral characteristics. Harvesting area （hectares） and landscape metrics were quantified through spatial and landscape pattern analyses in ArcGIS 10.7 and Fragstats 4.2. The results showed that the harvested area and harvest rate of Miscanthus lutarioriparius peaked in 2015 （57686.06 hm²； 55.69%） and declined to their lowest levels in 2019 （3743.21 hm²； 4.59%）. Following policy adjustments after 2018， harvesting intensity decreased， with spatial shifts toward the southern and eastern Lake regions， reflecting a northeastward migration trend. While early harvesting exhibited no preference for patch size， later mechanization promoted harvesting in large， contiguous Miscanthus lutarioriparius， reducing costs and improving efficiency. Correlation analyses indicate that harvesting maintained community aggregation and total area but altered shape complexity and spatial cohesion. These findings suggest that strategic planning of harvesting activities is essential to stabilize Miscanthus lutarioriparius populations， prevent further decline， and support wetland ecosystem. Expanding harvesting ranges may provide a pathway to achieving ecological and economic synergy for this species.

In order to provide scientific basis for precise fertilization of sorghum，Sorghum sudanense and Sorghum bicolor × S. sudanense hybrid in China，this study was carried out by using a new method of crop soil testing and recommended fertilization system research. The results showed that the regression equations of relative yield of sorghum，S. sudanense and S. bicolor × S. sudanense hybrid under nitrogen deficiency treatment in China with the contents of soil total nitrogen （TN），soil alkaline hydrolysis nitrogen （AHN） and soil organic matter （OM） were as follows： y＝14.533ln（x _TN） + 79.118，y＝16.607ln（x _AHN）-0.035，y＝-0.056x _OM ² + 3.126x _OM + 45.625. The 1st to 7th grade indicators of AHN for sorghum，S. sudanense and Sorghum bicolor × S. sudanense hybrid in China were ≥414，227-414，124-227，68-124，38-68，21-38 and <21 mg/kg，respectively. The 1st to 7th grade indicators of TN were ≥4.3，2.2-4.3，1.1-2.2，0.6-1.1，0.3-0.6，0.15-0.3 and <0.15 g/kg in sequence. The 3st to 7th grade indicators of OM were 16-41，（10-16，41-47），（6-10，47-51），（2-6，51-55） and （<2，≥55） g/kg，respectively. When the nitrogen fertilizer use efficiency was 30%-50%，and the target yield of sorghum and S. sudanense seeds was determined to be 4.5-15 t/hm²，the suitable nitrogen application rate for soil grades 1 to 7 were 0，21-115，41-230，62-345，83-460，104-575 and 124-690 kg/hm²，respectively. When the target yield of fresh grass for sorghum，S. sudanense and Sorghum bicolor × S. sudanense hybrid was determined to be 45-240 t/hm²，the suitable nitrogen application rates for soil grades 1 to 7 were 0，27-240，54-480，81-720，108-960，135-1200 and 162-1440 kg/hm²，respectively. When the target yield of silage for sorghum，S. sudanense and Sorghum bicolor × S. sudanense hybrid was determined to be 30-120 t/hm²，the suitable nitrogen application rates for soil grades 1 to 7 were 0，33-220，66-440，99-660，132-880，165-1100 and 198-1320 kg/hm²，respectively.

Erosion control blanket technology is a practical and environmentally friendly ecological restoration method. This article systematically reviews nearly a century of global application history of erosion control blankets. The application of erosion control blanket demonstrates significant ecological benefits for soil and water conservation，soil improvement，and vegetation restoration. Advantages of erosion control blanket in ecological restoration are illustrated as wide material availability，high construction efficiency，ease of maintenance，low cost，and environmental friendliness. Regarding challenges in erosion control blanket application such as the lack of standardization in producing，weak long-term ecological data，poor performance on difficult sites，and outdated instillation techniques and equipment，this review proposes prospects to provide theoretical foundations for advancing the sustainable application of erosion control blankets in ecological restoration. Future research will focus on establishing standardized production systems，investigating medium-to-long-term ecological effects，and developing technological process and mechanical construction equipment.

The spotted alfalfa aphid （Therioaphis trifolii） is recognized as one of the most damaging pests of alfalfa （Medicago sativa）. The application of exogenous elicitors represents a viable and environmentally friendly strategy that bolsters plant defenses while diminishing the risks that chemical pesticides pose to plants and the environment. This study focused on aphid-susceptible alfalfa cultivar， WL343 at the full-bloom stage. Salicylic acid （SA） and methyl jasmonate （MeJA） were sprayed with three concentrations （0.01， 0.1 and 1 mmol/L） to measure the effects on honeydew excretion and population growth of Therioaphis trifolii. The effects of exogenous elicitors at optimal concentrations on physiological characteristics of alfalfa under spotted alfalfa aphid stress were also analyzed. Results indicated that both SA and MeJA significantly reduced honeydew excretion and aphid population density， and optimal concentrations of SA and MeJA were 0.1 mmol/L and 0.01 mmol/L， respectively. The application of exogenous SA and MeJA significantly boosted the contents of soluble sugars， tannins and flavonoids， and enhanced the activities of polyphenol oxidase， superoxide dismutase and phenylalanine ammonia-lyase. Consequently， this regulated the physiological and metabolic responses of alfalfa， which suppressed aphid honeydew excretion and population growth thereby enhancing the plant defense against Therioaphis trifolii.

To explore the optimal legume-grass sowing ratio for synergistically improving yield and quality, a two-year field experiment with multiple mowings was conducted on the Loess Plateau. Five sowing patterns of white clover (Trifolium repens) and tall fescue (Festuca arundinacea) were evaluated, including monocultures of each species and mixtures at legume-to-grass ratios of 1:1, 1:2, and 1:3. The study aimed to assess the seasonal dynamics of forage yield and nutritional quality under different patterns and to identify the optimal strategy using a coupling coordination degree model. The results indicated that mixed sowing exhibited significant overyielding effects. Specifically, the mixtures with 1:2 and 1:3 ratios achieved the highest total yields, which were significantly increased by 23.92%-62.71% compared to monocultures (P<0.05). Regarding quality, compared with the monoculture of tall fescue, mixed sowing effectively increased crude protein content and reduced fiber content. The coupling coordination degree analysis of yield and quality demonstrated that the 1:2 legume-grass ratio is the optimal pattern for achieving synergistic development. This pattern not only achieved synchronous optimization in yield and quality but also maintained a high-level coordination state throughout the growing season. Consequently, it extends the window period for optimal utilization, making it the ideal strategy for establishing high-yielding, high-quality, and stable grasslands.

Leymus chinensis is an important native forage grass species in China， yet its low seed setting rate greatly constrains large-scale production and utilization. To identify the key traits influencing seed setting and to evaluate their relative contributions， this study examined 100 Leymus chinensis germplasms collected from different geographic origins. Fifteen traits closely related to seed setting were measured， including seed number， spike weight， seed weight， floret number， spikelet number， spike length， number of spike knots， vegetative plant height， reproductive plant height， leaf length， leaf width， seed setting percentage， thousand seed weight， and the number of vegetative and reproductive branches. The results showed that there was substantial genetic variation among the germplasms， with coefficients of variation for the 15 traits ranging from 10.88% to 56.05%. Correlation analysis showed that spike weight， seed number， seed weight， and thousand seed weight were significantly and positively correlated with seed setting rate， indicating their central roles in reproductive success. Multiple regression and hierarchical partitioning analyses demonstrated that seed number had the greatest contribution to seed setting rate， accounting for 31.57% of variation. Principal component analysis indicated that the first five principal components collectively explained 78.126% of the total variance. Based on a comprehensive evaluation of these traits， ten germplasms （77， 23， 24， 37， 35， 20， 57， 10， 22， 7） were identified as superior germplasms with high reproductive potential and stable performance across multiple traits.

Mowing is a common management and utilization method in grasslands. Understanding the ecological adaptive strategies of plant to mowing disturbance is the prerequisite for scientific implementation of mowing management. This study was conducted using a pot controlled experiment to investigate the effects of three mowing intensities on the functional traits and compensatory growth of Cynodon dactylon and Lolium perenne. The results showed that with the increase of mowing intensity， plant height， leaf area， root length， and root surface area of both C. dactylon and L. perenne decreased significantly. After 15 days of mowing， the tiller number of C. dactylon significantly increased under moderate and high mowing intensities， while mowing significantly increased the growth rate of both species. The aboveground biomass of both C. dactylon and L. perenne reached the peak under light mowing intensity， which was significantly higher compared with that of the control. The specific root length of C. dactylon， and the specific leaf area and specific root length of L. perenne were significantly decreased with the rising mowing intensities. The compensation index of C. dactylon was the highest under light mowing， whereas L. perenne had the highest compensation index under moderate mowing. Both species demonstrated compensatory growth in plant height under their respective mowing intensities， reaching overcompensation levels. Based on the integrated responses of traits including tiller number， growth rate， biomass and its allocation， post-mowing response of C. dactylon primarily is characterized by increases in tiller number and growth rate， whereas under light to moderate mowing， L. perenne exhibited increased aboveground biomass， a reduced root：shoot ratio， and higher growth rates during late growth. This suggests that the two species may achieve compensatory growth through different trait adjustments.

This study aimed to reveal the effects of three carbendazim concentrations on physiological characteristics and bacterial community of silage maize in three maturity stages （big trumpet stage，milk stage，and dough stage）. Results showed that the net photosynthetic and transpiration rate at the big trumpet stage and dough stage decreased by 9.50 µmol/（m²·s） and 15.2 µmol/（m²·s），1.75 mmol/（m²·s） and 2.59 mmol/（m²·s），respectively （P<0.05） compared with milk stage. Compared with at the big trumpet stage and dough stage，the moisture retention capacity at the milk stage increased by 24.50% and 13.20%，respectively （P<0.05）. The numbers of aerobic bacteria，Escherichia coli，and lactic acid bacteria at the milk stage and dough stage were significantly reduced （P<0.05） compared with the big trumpet stage. The concentration of carbendazim had no significant impact on the physiological characteristics or bacterial numbers of silage maize. At the genus level，the four bacteria with the highest relative abundance were Sphingomonas，Massilia，Rhodococcus，and Frigoribacterium. Different concentrations of carbendazim significantly affected the relative abundances of Pseudonocardia，Clostridium_sensu_stricto_1，Friedmanniella，unclassified_o_Micrococcales，Luteimonas，Steroidobacter，and Acinetobacter （P<0.05）. Considering the utilization of maize silage and the need to prevent the proliferation of drug-resistant bacteria，this study recommends applying low concentration carbendazim on silage maize.

This study investigated the effects of variety and planting density on the agronomic traits and yield of silage maize （Zea mays）， and aimed to identify optimal variety-density combinations to alleviate the silage forage supply-demand imbalance in Yuyang District， Shaanxi Province. Growth characteristics and yield performance of 10 varieties were evaluated under three planting densities （82 500， 90 000， and 97 500 plants/hm²）， and comprehensive evaluation was conducted using Grey Relational Analysis （GRA）. Results showed that variety had a significant effect on plant height （P<0.01）， with the plant heights of both Xianda 6331 and Zhongnongda 787 exceeding 320 cm. Both the leaf area index and light interception rate increased significantly with increasing planting density （P<0.01） and were positively correlated with each other （P<0.001）. The fresh forage yield was the highest under 90 000 plants/hm². Comprehensive analysis with GRA identified varieties Zhongnongda 787， Lilong 915， and Jingke 627 as the top varieties. In conclusion， an optimal planting density of 90 000 plants/hm² is recommended for Yuyang District， with Zhongnongda 787 and Lilong 915 as suitable varieties. This provides theoretical and technical support for efficient silage maize production in this region.

Salt stress is one of the most critical abiotic factors limiting plant growth and development. An in-depth understanding of the molecular mechanisms underlying salt tolerance in forage grasses is essential for the improvement of saline-alkali soils and the breeding of salt-resistant varieties. In this study， Festuca rubra L. was subjected to a series of salt concentration gradients to determine the concentration most sensitive to root response， which was identified as 100 mmol/L NaCl. Based on this， F. rubra roots exposed to 100 mmol/L NaCl were analyzed using RNA-Seq technology to elucidate transcriptomic changes under salt stress. A total of 43 091 differentially expressed genes （DEGs） were identified compared with the control group， including 16 486 significantly upregulated and 26 605 significantly downregulated genes. Gene Ontology （GO） enrichment analysis revealed that these DEGs were primarily enriched in intracellular signal transduction， protein transport， cytosol and GTPase activity. KEGG enrichment analysis showed that the DEGs were mainly involved in metabolic pathways such as the mitogen-activated protein kinase （MAPK） signaling pathway， endoplasmic reticulum protein processing， and the tricarboxylic acid （TCA） cycle. Within the MAPK signaling pathway， genes encoding MAPKs related to salt stress resistance were upregulated in F. rubra roots. Moreover， several transcription factor families， including C2H2， bHLH， NAC， MYB， WRKY， and bZIP， exhibited differential expression under salt stress， with members of the C2H2 family showing particularly strong responses. In conclusion， under 100 mmol/L NaCl stress， F. rubra roots primarily respond by upregulating MAPK gene expression， activating the MAPK signaling pathway， and regulating the activity of key transcription factors to enhance osmotic adjustment and salt tolerance.

Biochar has shown great potential for improving soil physicochemical properties and enhancing crop productivity. However， the mechanisms by which the combined application of biochar and nitrogen fertilizer influences forage yield， soil nutrient dynamics， and soil microbial communities in legume-grass mixed pastures remain unclear. In this study， a mixed pasture of alfalfa （Medicago sativa） and smooth bromegrass （Bromus inermis） was used to examine the effects of biochar and nitrogen fertilizer co-application on soil physicochemical properties， microbial biomass， diversity， and community structure， as well as their interrelationships. The results showed that the combined application of biochar and nitrogen fertilizer significantly enhanced soil nutrient availability. Compared with application of nitrogen fertilizer alone at 180 kg/hm²， the treatment of 8 t/hm² biochar plus 180 kg/hm² nitrogen fertilizer increased soil total nitrogen by 35.71%， ammonium nitrogen by 42.19%， and available potassium by 34.38% （P < 0.05）， while no significant difference was observed in total phosphorus content. Biochar addition markedly altered soil microbial community structure， increasing the number of unique bacterial ASVs （e.g.，10 372 in the 8 t/hm² biochar plus 180 kg/hm² nitrogen treatment） and elevating the relative abundance of Actinobacteria， Chloroflexi， Gemmatimonadota， and Sphingomonas. Alpha diversity analysis indicated that nitrogen fertilization alone reduced bacterial richness， whereas biochar addition had no significant effect on alpha diversity indices. Correlation analysis revealed that variations in the relative abundance of different soil bacterial groups were primarily associated with soil total nitrogen， nitrate nitrogen， available potassium， and forage yield. In conclusion， the combined application of 8 t/hm² biochar and 180 kg/hm² nitrogen fertilizer significantly improves soil fertility， promotes nutrient cycling， and enhances forage productivity. These findings provide a theoretical basis for the use of biochar-nitrogen integration to support degraded grassland restoration and sustainable pasture management.

To evaluate the salt tolerance of eight Trifolium repens germplasms，this study applied a continuous salt stress treatment using saline water with an electrical conductivity （EC） of 12 dS/m，while a nutrient solution （EC=0.8 dS/m） as the control. Morphological，physiological，and photosynthetic traits were determined to provide baseline data for breeding salt-tolerant T. repens varieties. The results showed that saline irrigation significantly inhibited seedling growth and photosynthesis across all germplasms，reducing plant height，stem diameter，branch number，leaf length，leaf width，petiole length，net photosynthetic rate （Pn），transpiration rate （Tr），stomatal conductance （Gs），and intercellular CO₂ concentration （Ci） to varying degrees. In contrast，soluble sugar，proline，and hydrogen peroxide （H₂O₂） contents increased significantly （P<0.01）. Germplasm TRYJ010 exhibited minimum reductions in plant height，Pn，Tr，and Gs，together with the greatest increase in soluble sugar and the smallest increase in H₂O₂. Conversely，germplasm TRYJ065 showed pronounced declines in plant height and Pn，the smallest increase in proline，and the largest reductions in Tr and Gs. Principal component analysis indicated H₂O₂ content，plant height，Pn，and branch number as key indicators of salt tolerance. Based on D-value comprehensive evaluation，the salt tolerance ranking was： TRYJ010>XJ03>Kaola>TRYJ014>XJ08>XJ07>XJ04>TRYJ065. Among them，TRYJ010 represents a promising parental line for breeding salt-tolerant T. repens varieties in Xinjiang.

The typical steppe has long experienced high intensity grazing pressure， resulting in biodiversity loss and the degradation of ecosystem services. Although appropriate grazing can promote nutrient cycling and improve soil nutrient levels in grassland ecosystems， the specific effects of rational grazing on soil nutrient dynamics in typical steppe regions remains insufficiently understood. In this study， five representative steppe zones in Hulunbuir City were selected as research sites. Comparative experiments were conducted between grazing balance zones （supporting 0.6 to 1.5 sheep units per hectare） and grazing exclusion areas to examine soil nutrient variations across different soil depths. The results showed that soil nutrient indicators， including organic carbon， total nitrogen， total phosphorus， total potassium， and available phosphorus， were consistently higher in grazing balance zones than in grazing exclusion areas. Grazing exclusion exerted positive effects on soil organic carbon and total nitrogen across all layers （0-30 cm） in regions with lower aridity indices. The grazing response ratios of major soil nutrients exhibited strong correlations with climatic factors： grazing response ratio of soil total nitrogen was significantly positively correlated with grazing response ratio of soil total phosphorus， available phosphorus and aridity index， grazing response ratio of soil total phosphorus showed a highly positive correlation with aridity index， while all nutrient response ratios were negatively correlated with precipitation. In conclusion， rational grazing effectively enhances soil nutrient levels in typical steppe ecosystems.

This research was conducted in the Stipa breviflora desert steppe of Siziwang Banner， Inner Mongolia. We established four stocking-rate treatments 0， 0.91， 1.82， and 2.71 sheep/（hm²·a） and plant community was categorized into five plant functional groups-perennial rhizomatous grasses， perennial forbs， perennial bunchgrasses， annual–biennial herbs， and shrubs/sub-shrubs. Quadrat sampling was used to measure plant height， cover， density， above-ground biomass， and species composition in August 2022. We calculated importance values and applied principal component analysis （PCA） to evaluate productivity-diversity coupling. Results showed that：（1） Species richness exhibited a hump-shaped response to stocking rate （22， 24， 22， and 21 species， respectively）， while morphological traits and productivity of the plant functional groups generally declined with increasing grazing pressure. （2） Importance-value analysis showed that the relative importance of perennial bunchgrasses increased from 40% to 68%， while their contribution to community productivity rose from 60% to 95%. PCA further indicated that productivity and diversity together accounted for 66.12% of the variance， which was primarily driven by this functional group.（3） A positive linear relationship was observed between species richness and productivity in the perennial forb group under no grazing， light grazing， and moderate grazing， whereas this relationship under heavy grazing was found in shrubs/sub-shrubs group. No other functional groups exhibited significant correlations. These results demonstrate that while stocking rate significantly alters plant functional group composition， species diversity alone is not a direct determinant of productivity， indicating complex interactions among disturbance， diversity， and productivity. Since perennial bunchgrasses play a crucial role in supporting productivity at higher stocking rates， grazing management strategies should prioritize the conservation and regulation of this functional group to ensure sustainable use and the ecological stability of the desert steppe.

As a fundamental component of regional water resource planning and management， reference evapotranspiration （ET₀） requires a thorough investigation into the time-lag effects and synergistic interactions of different environmental variables for a comprehensive understanding. However， the response time of ET₀ to vapor pressure deficit （VPD） and temperature and their influencing factors remains unclear. In this study， time-lag effects and their interactions for VPD， temperature （including maximum， minimum， and mean temperatures）， Normalized Difference Vegetation Index （NDVI） on ET₀ were analyzed using data from 107 meteorological sites across Inner Mongolia during 2000—2020. The results indicated： ET₀， VPD， temperature， and NDVI exhibited increasing trends over the study period. Notably， the time lag of ET₀ in response to VPD was longer compared to air temperature， particularly for minimum temperatures in high-altitude regions. ET₀ exhibited a stronger potential sensitivity to VPD compared to mean temperature， whereas the response to extreme low temperatures exceeded that to maximum temperature and VPD. an increase in NDVI was found to shorten the lag time of ET₀ in response to air temperature， whereas it prolonged the lag time of ET₀ in response to vapor pressure deficit.