Plant functional traits are effective indicators and predictors of environmental change, revealing plants’ ecological countermeasures and adaptability through phenotypic plasticity. We conducted a 6-year grazing experiment on typical temperate grassland to assess the impact of different grazing periods on the plasticity and variability of the functional traits of Leymus chinensis and the relationship between traits and individual plant biomass. Our study included four treatments: CK (enclosure), T1 (grazing in May and July), T2 (grazing in June and August), and T3 (grazing in July and September). The results for 13 functional traits indicated that the T3 treatment showed the smallest reduction in individual plant biomass, plant height, leaf area, stem length, and leaf length, making it the most effective type of grassland management and optimal for the maintenance and restoration of L. chinensis traits. Under T1, T2, and T3, the plasticity of stem weight, total leaf weight, total leaf area, and stem length was higher and crucial for regulating individual plant biomass. The results underscore that the changes and plasticity of dominant species under grazing treatments are key to understanding the relationship between ecosystem function and grassland management. This study provides a theoretical basis and data support for the adaptive utilization and restoration management of typical grassland resources.

Urbanization in the 21st century has reshaped carbon stock distributions through the expansion of cities. By using the PLUS and InVEST models, this study predicts land use and carbon stocks in Wuhan in 2050 using three future scenarios. Employing local Moran’s I, we analyze carbon stock clustering under these scenarios, and the Getis–Ord Gi* statistic identifies regions with significantly higher and lower carbon-stock changes between 2020 and 2050. The results reveal a 2.5 Tg decline in Wuhan’s carbon stock from 2000 to 2020, concentrated from the central to the outer city areas along the Yangtze River. By 2050, the ecological conservation scenario produced the highest carbon stock prediction, 77.48 Tg, while the economic development scenario produced the lowest, 76.4 Tg. High-carbon stock-change areas cluster in the north and south, contrasting with low-change area concentrations in the center. This research provides practical insights that support Wuhan’s sustainable development and carbon neutrality goals.

Litter serves as a crucial source of soil nutrients in sandy land ecosystems. Soil enzyme activities and their stoichiometric ratios act as essential “bridges” linking microbial metabolism with nutrient cycling, thereby reflecting the availability of soil nutrients and the sensitivity to microbial substrate limitations. To investigate the effects of litter quality changes on soil nutrients, enzyme activities, and stoichiometric ratios in sandy land, leaf litter and surface soil were collected from four sand-fixing forests in the Mu Us Sandy Land, including YC (Corethrodendron fruticosum), NT (Caragana korshinskii), ZSH (Amorpha fruticose), and SL (Salix cheilophila). These samples were then used for indoor cultivation. Experiments with these four leaf litter types were carried out; one treatment with no litter added served as the control. Our aim was to systematically study the changing characteristics of enzyme activities related to soil carbon, nitrogen, and phosphorus with different litter inputs. The results indicate the following: (1) Compared to the control treatment with no litter added (CK), the addition of all four types of litter significantly increased soil organic carbon, total nitrogen, and alkaline nitrogen contents. The addition of NT and YC litter significantly increased dissolved organic carbon, microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN). (2) The addition of the four types of litter had different effects on the soil enzyme activity, showing increasing trends overall. A chemical analysis of the enzyme activity revealed that the soil was limited in nitrogen and phosphorus. After the addition of the ZSH, NT, and YC litter, the enzymatic C/P acquisition ratio (E_C/P) and enzymatic N/P acquisition ratio (E_N/P) decreased significantly, alleviating the limitation of phosphorus. After the addition of the NT litter, the enzymatic C/N acquisition ratio (E_C/N) increased significantly, alleviating the limitation of soil nitrogen. (3) A correlation analysis showed that the soil nutrients had varying degrees of correlation with enzyme activity and their stoichiometric ratio. The redundancy analysis results show that MBN, TN, MBC/MBN, organic carbon, and available nitrogen were key factors influencing soil enzyme activity and stoichiometric ratios. These results provide a reference for nutrient cycling during sandy soil restoration, and they provide essential data support for the development of fragile ecosystem models in the context of global change.

Monoculture and legume–grass mixed cropping are the two most common planting methods, with mixed cropping generally demonstrating higher hay yield and superior nutritional quality compared to monoculture. However, research on legume–grass mixed cropping for establishing cultivated pastures in typical sand-fixing vegetation areas of the Mu Us Sandy Land remains scarce. These knowledge gaps have hindered the synergistic integration of forage production and ecological restoration in the region. This study conducted mixed cropping trials in the sand-fixing vegetation zone of the Mu Us Sandy Land using Dahurian wildrye (Elymus dahuricus), Mongolian wheatgrass (Agropyron mongolicum), and Standing milkvetch (Astragalus adsurgens) to investigate the effects of species combinations and planting ratios on forage productivity and nutritional quality, aiming to determine the optimal planting strategy. Results showed that in the first establishment year, the yield of all mixed cropping systems significantly exceeded that of monocultured Dahurian wildrye and Mongolian wheatgrass. All mixed cropping combinations exhibited land equivalent ratios (LER) and relative yield totals (RYT) below 1, indicating varying degrees of interspecific competition during the first year, with grass species generally demonstrating stronger competitive abilities than legumes. Mixed-cropped forages showed higher crude protein, crude fat, and crude ash content compared to monocultures, alongside lower neutral detergent fiber (NDF) and acid detergent fiber (ADF) levels, suggesting improved relative feed value (RFV). Among the combinations, E₅A₅ and E₆A₄ (5:5 and 6:4 ratio of Dahurian wildrye to Standing milkvetch) achieved higher RFV, with RFV gradually declining as the legume proportion decreased. In conclusion, both monoculture and legume–grass mixed cropping are viable in the Mu Us Sandy Land’s sand-fixing vegetation areas and the E₅A₅ combination (5:5 ratio of Dahurian wildrye to Standing milkvetch) as having the highest overall score, demonstrating that this mixed cropping ratio optimally balances yield and nutritional quality, making it the recommended planting protocol for the region. This mixed cropping system offers a theoretical foundation for efficiently establishing artificial pastures in the Mu Us Sandy Land, supporting regional pastoral industry development and desertification mitigation.

Understanding the community assembly mechanisms and stability of artificial sand-fixing forests is critical for the management of desert ecosystems. This study investigated the understory vegetation of four artificial sand-fixing shrub forests in the Mu Us Sandy Land to understand community assembly mechanisms and stability by analyzing niche characteristics, interspecific associations, and community stability. The results showed the following: (1) Lc (Leymus chinensis), Ee (Euphorbia esula), Gd (Grubovia dasyphylla), and Ch (Corispermum hyssopifolium) all have wide ecological niches and high importance values, serving as key species for maintaining community function. (2) The understory herbaceous plant communities of S. psammophila, A. ordosica and C. fruticosum exhibited low niche overlap, and the A. fruticosa understory herbaceous plant community showed high niche overlap. (3) The overall association of the understory herbaceous plant communities of S. psammophila, A. ordosica, and C. fruticosum is positive, while that of the understory herbaceous plant community of A. fruticosa is negative; the interspecific associations are weak, and the species show an independent distribution pattern. (4) Among the four understory herbaceous plant communities, the stability of the S. psammophila understory herbaceous plant community is relatively the highest, followed by A. ordosica and C. fruticosum understory herbaceous plant community, and the stability of A. fruticosa understory herbaceous plant community is the lowest. Furthermore, community stability was positively correlated with the variance ratio (VR) but negatively correlated with mean niche overlap. We recommend prioritizing S. psammophila and C. fruticosum for sand fixation and conserving key herbaceous species to optimize resource use and stabilize interspecific relationships. The novelty of this study lies in its integrated assessment of niche characteristics, interspecific associations, and community stability, and it primarily focused on the role of interspecific relationships. Future research should incorporate environmental drivers and shrub functional traits to disentangle the synergistic effects of biotic and abiotic factors, thereby providing a more robust scientific foundation for vegetation restoration in desert ecosystems.

This study proposes the Urban Landscape Emotion Analysis Framework (ULEAF) based on images of urban parks shared on social media. This framework integrates an emotion recognition module driven by a convolutional neural network (ConvNeXt Tiny) with a semantic extraction module supported by multimodal semantic matching models (CLIP and DeepSentiBank ANP lexicon). It constructs a systematic analysis pathway from semantic understanding to emotional perception, effectively overcoming the limitations of traditional research methods. Results indicate that positive emotion images predominantly correlate with nature, health, and openness, while negative emotion images are closely associated with the characteristics of decay, abandonment, and oppression, as well as loneliness and calmness, estrangement and disharmony, and gloom and bleakness. Findings reveal trends consistent with prior research, further validating the stable association between urban landscape visual features and emotional perception. The analytical framework developed in this study facilitates the systematic revelation of semantic characteristics and affective perception mechanisms in large-scale urban park imagery, providing scientific reference for optimizing urban park landscapes and implementing emotion-oriented design.