Basing on the livelihood vulnerability assessment framework， this study constructed a theoretical model of herders’ livelihood vulnerability. Using field survey data from 414 herder households in the pastoral areas of Inner Mongolia， the comprehensive index method was employed to evaluate their livelihood vulnerability. Furthermore， an Ordinary Least Squares （OLS） regression model was applied to analyze the impacts of herders’ climate change adaptation behaviors on their livelihood vulnerability. The results indicated a correlation between herders’ livelihood vulnerability and grassland resource endowments. Furthermore， adaptation behaviors such as purchasing forage and increasing the number of days of stall-feeding were found to exacerbate their livelihood vulnerability. Adaptation measures， such as selling weak livestock， constructing sheds， adjusting livestock composition， and well-digging， had a mitigating effect on herders’ livelihood vulnerability. The impact of grassland ecological compensation and reward policies on livelihood vulnerability exhibited a threshold effect and heterogeneity. Based on the research conclusions， the following recommendations were proposed： creating a pastoral innovation network， providing climate-adaptive technical guidance， and establishing a dynamic adjustment mechanism to formulate regionally differentiated compensation and reward standards. These measures aimed to serve as a reference for the government in formulating effective policies to alleviate herders’ livelihood vulnerability， enhance their capacity to withstand climate change shocks， and promote the sustainable development of animal husbandry.

To elucidate the adaptive capacity of Cyperus esculentus to salt-alkali stress and clarify the synergistic effects of salt and alkali， a two-factor completely randomized design was employed using ‘Zhongyousha 1’ as the test material. Compound salt-alkali stress was imposed using six salt gradients （0， 100， 150， 200， 250， and 300 mmol·L^-1 Na⁺） and three alkali gradients （pH 7.0， 8.5， and 10.0）. Seed germination， seedling growth， leaf osmolytes， and antioxidant parameters were determined under these conditions. The results showed that germination percentage， fresh weight， and seedling length decreased significantly with increasing salt stress （P<0.05）. Notably， the lethal salt threshold under strong alkali conditions （250 mmol·L^-1） was lower than that in neutral and weak alkali environments （300 mmol·L^-1）. With intensifying stress， seedlings mitigated damage by accumulating proline， soluble sugars， and soluble proteins for osmotic adjustment， and by enhancing peroxidase and catalase activities. In conclusion， Cyperus esculentus adapted to salt-alkali stress by regulating osmotic and antioxidant capacities； however， excessive salt and alkali levels exceed its tolerance threshold， causing irreversible damage. These findings provide a scientific basis for promoting the cultivation of Cyperus esculentus in saline-alkali lands in Xinjiang.

Biogenic volatile organic compound （BVOC） produced and emitted by plants exhibit high chemical reactivity in the atmosphere， exerting significant influence on atmospheric chemistry and climate change. They constitute important atmospheric trace gases. To elucidate the seasonal variation patterns and driving factors of BVOC emissions in alpine meadows， this study employed a dynamic headspace sampling system coupled with GC/MS technology for in situ monitoring in alpine meadows of northwestern Yunnan from July to October 2024， concurrently recording vegetation composition and environmental factors. we detected over 130 BVOCs belonging to 11 classes， including isoprene and monoterpenes. Total BVOC emission rates exhibited pronounced seasonal variation， peaking in July [（2485.51±847.08） μg·m^-2·h^-1] and reaching a minimum in October [（206.27±166.11） μg·m^-2·h^-1]. Emissions from July to August were dominated by isoprene （nearly 100%）， while emissions from September to October exhibited greater diversity， with notable increases in green leaf volatiles， sesquiterpenes， and aldehydes. Random forest analysis indicated isoprene as the key compound distinguishing monthly emission patterns. BVOC emissions were jointly influenced by temperature， light intensity， and vegetation structure： high temperatures and strong light promoted isoprene release， whereas low temperatures and plant senescence enhanced non-light-dependent BVOC emissions. Coverage of Carex muliensis was significantly positively correlated with isoprene emissions， while co-occurring species heterogeneity and flowering period variations enhanced BVOC emission diversity. These findings would aid in our understanding of BVOC-driven atmospheric processes and climatic feedbacks within the alpine meadows of northwestern Yunnan.

Bacterial extracellular polysaccharides （EPS） show great potential in enhancing plant stress resistance， but their mechanism of action on drought resistance in alfalfa （Medicago sativa） remains unclear. In this study， Alfalfa ‘Juneng 551’ was used as the experimental material， and seed coating technology was employed to investigate the drought resistance effect of Cp2-EPS from Erwinia persicina. Treatments included an uncoated control （CK）， a coating matrix control （T1）， and four Cp2-EPS concentration treatments （0.5， 1.0， 1.5， 2.0 g·L^-1， denoted as T2-T5）. Drought stress was applied after 21 days of seedling growth by maintaining soil relative water content at 40% for 14 days， and related physiological and growth indicators were measured. The results showed that Cp2-EPS coating significantly alleviated the growth inhibition caused by drought in alfalfa， with the 1.0 g·L^-1 （T3） treatment demonstrating the best effect. Compared with CK， the T3 treatment increased root length， shoot length， fresh weight， and dry weight by 17.87%， 17.87%， 74.53%， and 46.34%， respectively. Leaf photochemical quantum yield Y（II）， maximum photochemical efficiency of PSII， and total chlorophyll content were also significantly improved. In summary， Cp2-EPS seed coating can mitigate drought-induced oxidative damage by enhancing photosynthetic performance， and 1.0 g·L^-1 was identified as the optimal concentration. This study provides theoretical and technical references for developing eco-friendly drought-resistant coating agents and sustainable alfalfa production.

Elucidating the distribution patterns and driving mechanisms of herbaceous plant diversity provides a critical scientific basis for developing ecological protection strategies. This study conducted a systematic survey of herbaceous plant communities in Yongdeng County， Lanzhou City， using a grid sampling method. We investigated four distinct habitat types-temperate steppe， temperate desert steppe， alpine meadow， and cultivated grassland-to explore the effects of topographic and soil factors on species diversity. The results indicated that： （1） A total of 356 wild herbaceous species belonging to 197 genera and 53 families were recorded. Poaceae， Asteraceae， and Fabaceae were the 3 dominant families， accounting for 38% of the total species richness. （2） The effects of topographic factors on diversity were habitat-specific. The trends of alpha-diversity indices along the elevational gradient differed significantly among grassland types， with the temperate steppe showing the most sensitive response. Species richness exhibited a significant unimodal non-linear response to slope gradient and aspect； notably， species richness peaked on shady slopes and gentle slopes due to favorable hydrothermal conditions. （3） Soil nutrients were identified as key drivers of diversity variation. Species richness was positively correlated with soil total carbon， but it showed significant negative correlations with soil total nitrogen and total phosphorus （P<0.05）. （4） Multivariate analysis further revealed that species richness was primarily driven by soil carbon content （P<0.01）. The Simpson index was significantly correlated with soil phosphorus content （P<0.01）， while the Shannon-Wiener index showed a significant co-variation with the evenness index （P<0.05）.

This study employed high-throughput transcriptome sequencing to analyze gene expression changes in Medicago truncatula under salt stress （150 mmol·L^-1 NaCl） and alkali stress （135 mmol·L^-1 NaHCO₃+15 mmol·L^-1 Na₂CO₃） at five time points： 0 h， 6 h， 12 h，24 h and 48 h. The results showed that alkali stress induced more drastic gene expression changes， with downregulated genes generally outnumbering upregulated ones. Differentially expressed genes were significantly enriched in pathways related to ABA signaling transduction， osmotic regulation， antioxidant defense， and ion homeostasis. A total of 60 genes were commonly upregulated and 16 genes were commonly downregulated under both salt and alkali stresses. The commonly upregulated genes were mainly involved in stress-resistance mechanisms such as hormone regulation and signal transduction， whereas the commonly downregulated genes covered multiple functional categories including hormone signaling and cell wall remodeling. This study elucidates key genes involved in the responses of M. truncatula to salt and alkali stresses and identifies candidate genes for salt and alkali tolerance， providing a theoretical basis for molecular breeding of alfalfa.

Mowing and fertilization can optimize the transfer and storage of systemic nutrients during the growing season by interfering with the physiological process of nutrient reabsorption in alfalfa. This study was to investigate the differences in nutrient reabsorption in alfalfa leaves and find the balance point of plant nutrient balance. The experiment set up five fertilization gradients （CK， F1， F2， F3， F4） under different mowing （3 times a year and 4 times a year， denoted as M1 and M2） and fertilization （P₂O₅ and K₂O ratio of 3∶5） conditions on alfalfa leaves. The carbon， nitrogen， and phosphorus contents of mature and senescent leaves were measured， and the characteristics of nitrogen and phosphorus reabsorption efficiency were analyzed. The results showed that mowing and fertilization significantly increased the nitrogen and phosphorus content in leaves （P<0.05）. The overall carbon to nitrogen ratio and carbon to phosphorus ratio in leaves showed a decreasing trend， while the nitrogen to phosphorus ratio showed a trend of first increasing and then decreasing， both of which were greater than 16. The nitrogen and phosphorus reabsorption efficiencies in leaves were 25.08%-42.79% and 29.05%-44.30%， respectively. The nitrogen and phosphorus reabsorption efficiency was significantly positively correlated with the carbon， nitrogen， and phosphorus content of new leaves. Mowing promoted nitrogen and phosphorus reabsorption， while fertilization first promoted and then inhibited it. M2F2 had the highest carbon and nitrogen content in mature leaves and nitrogen and phosphorus reabsorption efficiency in senescent leaves， making the best nutrient acquisition strategy for alfalfa.

This study was conducted in an alfalfa field at the Luhuatai experimental site of the Institute of Plant Protection， Ningxia Academy of Agriculture and Forestry Sciences， where Beauveria bassiana and Metarhizium anisopliae were applied in alternate rows for three consecutive years. The results showed that both entomopathogenic fungi provided effective control of Odontothrips loti， with average control efficacies of 34.8% and 30.3%， respectively. Compared with the control， three years of B. bassiana application significantly improved soil physicochemical properties， with available phosphorus and soil organic carbon increasing by 67.2% and 41.7%， respectively， showing greater improvement than M. anisopliae. Soil enzyme activities were also enhanced， with increases of 36.91% in sucrase， 64.20% in alkaline phosphatase， and 31.03% in catalase. Application of M. anisopliae increased sucrase activity by 30.32% and catalase activity by 24.42% relative to the control. Compared with the soil bacterial community， soil fungal community structure was more strongly altered by the two biocontrol fungal treatments. Meanwhile， the relative abundance of beneficial taxa such as Sphingomonas increased， whereas the proportion of pathogenic fungi such as Fusarium declined. Overall， this study provides a theoretical basis and practical reference for pest biological control and the sustainable development of grassland agriculture in the Ningxia region.

Aldo-keto reductase （AKR） is widely present in various organisms and plays key roles in plant growth， development and stress responses. Bermudagrass （Cynodon dactylon （L.） Pers.） exhibits rapid growth and strong comprehensive stress tolerance， making it widely utilized in landscaping， turfgrass for sports fields， ecological restoration and forage production. In this study， a total of 88 members of AKR gene family were identified from the bermudagrass genome， which were clustered into 7 subfamilies and unevenly distributed across the 30 chromosomes of bermudagrass. Analysis of cis-acting elements in the promoter regions indicated that all the members contain varying numbers of light-responsive， hormone-responsive and stress-responsive elements， suggesting that this gene family may be involved in multiple growth， developmental， and stress response processes. Different AKR gene members exhibited distinct expression patterns under different salt treatment durations and in different organs. The overall expression response intensity of genes in roots was generally higher than that in leaves， with a greater number of genes being upregulated， whereas most genes in leaves were downregulated. Among them， CdAKR15， CdAKR30， CdAKR43， CdAKR48， CdAKR72， and CdAKR80 showed significant differences in expression levels under different salt stress durations. This study lays a foundation for further investigation of the response of bermudagrass AKR genes to salt stress.

Puccinellia tenuiflora is a halophyte with remarkable adaptability to the combined stress of saline and stagnant. The apoplastic barrier formed by endodermal thickening is likely crucial for this adaptation， in which the Casparian strip and suberin lamellae serve as key apoplastic barriers in endodermis for the radial transport of water and solutes. In this study， using Puccinellia tenuiflora as material， we cloned PtCASP1， a key gene involved in Casparian strip formation. Bioinformatic analysis， subcellular localization， and expression pattern analysis under saline， stagnant and combined saline-stagnant stresses were conducted. The results showed that the PtCASP1 gene was 552 bp in length， encoding 184 amino acids. It was a hydrophobic， stable protein and contained cis-acting elements responsive to gibberellin， drought stress， low temperature stress， and light response. Phylogenetic analysis indicated that PtCASP1 was closely related to those in Lolium multiflorum and Alopecurus aequalis. Immunofluorescence analysis revealed that the PtCASP1 protein exhibited dual localization in the nucleus and cell membrane. The expression level of the PtCASP1 gene in the roots of Puccinellia tenuiflora was significantly higher than that in the leaves， and it responded to saline， stagnant， and combined saline-stagnant stresses， with the highest relative expression levels at 72 hours post-treatment for all stress conditions. This study provides a reference for further investigation into the function of the Casparian strip in helping Puccinellia tenuiflora adapt to saline-stagnant combined stress.