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IntroductionThe COVID-19 pandemic has underscored the health benefits of green spaces, yet research on how specific elements of natural infrastructure affect well-being during the pandemic has been limited.MethodsThis study, conducted at Sichuan Agricultural University with 300 students in 2022, investigated how urban natural infrastructure impacts physical and psychological well-being during the pandemic. Different aspects of natural infrastructure, such as thermal comfort, air quality (negative ion concentration), and noise and light levels, varied in their positive effects on students’ health.ResultsThe findings revealed that 65.6% of university students felt reduced stress when engaging with outdoor spaces, and 72.8% of them renewed recognized the therapeutic value of nature.DiscussionThe study emphasizes the importance of incorporating natural elements into urban planning to enhance outdoor activity and well-being, especially in post-pandemic settings. Recommendations are provided for future urban design to address the therapeutic needs of specific populations.

Abstract Atmospheric nitrogen deposition may affect the biodeterioration process of stone monuments through direct and indirect pathways, but relevant studies are lacking. Therefore, taking the biologically colonized rocks around the Leshan Giant Buddha (World Heritage - Mixed Property) as the research objects, we studied the effects of multiple nitrogen addition levels (0, 9, 18, 36, 72 kg N hm-2 a-1; N0, N1; N2 ; N3; N4) on the bacterial community structure and soil nutrients on the surfaces of stones with four biocolonization types, including naked rock (NR), and lichen (LR), bryophyte (BS) and vascular plant (VS) colonization, to investigate the potential effect of atmospheric nitrogen deposition on the rock weathering of the Leshan Giant Buddha. The results demonstrated that nitrogen addition impacted soil carbon, nitrogen and phosphorus nutrients, as well as bacterial community structure and composition, but the responses to nitrogen input varied among different colonization types. Nitrogen fertilization promoted the accumulation of total organic carbon and total nitrogen in NR and LR, and increased the content of total phosphorus in VS. Bacterial α-diversity decreased with nitrogen addition in NR but increased with nitrogen addition in VS. Nitrogen addition significantly (R > 0.9, p

Urbanization accelerates habitat fragmentation and leads to the decline of biodiversity in cities. Urban greenway landscapes provide not only social functions but also important ecological services. In this study, taxonomic richness, abundance, diversity, and the distribution of soil meso- and microfauna were investigated in three different urban greenway landscapes to assess their environmental quality. Urban greenway landscapes that had a richer tree species composition, higher deciduous tree ratios, wider ecological greenspace, moderate soil temperature and moisture, and lower soil bulk density and less lead were conducive to the survival and development of the soil meso- and microfauna community. Different soil fauna groups had varied responses to different environmental conditions in urban greenway landscapes. Microarthropods were more sensitive to plant communities; in contrast, soil moisture was the most important abiotic driver for hygrophilous meso-micro fauna. Our study highlights the importance of deciduous trees for their rich litter input, and the wide ecological greenspace for its buffering effect on various disturbances, which promote the conservation of biodiversity in urban greenway landscapes.

IntroductionAs global urbanization intensifies, the physical and mental stressors of modern life have led to the growing prevalence of suboptimal health conditions. Spending time in a forest benefits human health and well-being. In this context, based on the forest spatial types (forest interior and forest edge spaces), landscape elements (architecture, water and roads) and forest stands (coniferous, broadleaf and bamboo forests), this study investigated the effects of different forest spatial landscape characteristics on the restorative potential for college students, aesthetic preference and eye movement behavior (total fixation duration and fixation count).MethodsIn this study, a total of 60 subjects were exposed to 42 photographs depicting typical forest landscapes acquired through field studies. The Short-version Revised Restoration and Preference Scale and eye-tracking technology, were employed to study the recovery efficiency and visual attraction of forest spatial of different forest spatial types, element compositions and forest stands.Results(1) The restorative potential and aesthetic preference score of forest edge spaces were significantly higher than those of forest interior spaces. (2) The restorative potential of bamboo forests was significantly higher than those of coniferous and broadleaf forests. (3) In terms of forest interior space, the restorative potential of “forest + 1 element” composition and “forest + 2 elements” composition was significantly higher than that of pure forest, and the restorative potential of interior space of bamboo forest was significantly higher than those of coniferous and broadleaf forests. (4) In terms of forest edge space, the restorative potential of “forest + 2 elements” composition was significantly higher than that of pure forest, and the restorative potential of pure forests was significantly higher than that of the “forest + 1 element” composition. (5) The restorative potential of forest spatial landscape characteristics positively correlated with aesthetic preference and negatively correlated with total fixation duration and fixation count. These results can provide a reference for future forest landscape research, construction and management.

Different sizes of clonal fragments contain various number of ramets with different spacer lengths, which strongly affects the redistribution of photosynthetic assimilates. Although clonal integration significantly affects rhizosphere processes via microbial enzymes under heterogeneous conditions, the effects of clonal fragment size (ramet number and spacer length) on rhizosphere N turnover processes remain poorly understood. Here, we sampled clonal fragments of Phyllostachys bissetii with different ramet numbers and spacer lengths to determine the relative effects of clonal integration and fragment size on rhizosphere processes and resource availability. We found that clonal integration had positive effects on the C and N availability of shaded ramets in clonal fragments with different ramet numbers, owing to the large resource storage in the fragment. However, it only promoted the dissolved organic carbon of the shaded ramets in clonal fragments with different spacer lengths. Results of regression analyses indicated that the response ratios of the soil variables of the shaded ramets first increased when the spacer length was about less than 30 cm and then decreased when the spacer became longer (about >30 cm), suggesting a cost–benefit tradeoff in the fragment. The contribution of the size of clonal fragment to the soil N turnover process was higher than that of clonal integration, whereas its contribution to soil C availability had the opposite effect. These results further revealed the mechanism of the size of clonal fragment in affecting the rhizosphere processes of stressed ramets, which is critical for the adaptation of P. bissetii to stressed habitats and further bamboo ecosystem N turnover under climate change.

The retaining wall is a passive engineering measure to prevent and control unsafe factors caused by rock collapse in the valleys. Existing studies have mainly focused on its functional robustness and safety features, with few exploring its visual quality in the landscape. A multiple regression analysis was applied to evaluate the Scenic Beauty Estimation (SBE) of the giant retaining wall in Jiuzhaigou’s (a world natural heritage site) Heye Village, then the factors affecting SBE were analyzed. It is found that enhancing the sense of perspective and spatial hierarchy of retaining-wall murals in narrow roads contributes to the extension of observers’ sight, which is the key to improving SBE. Furthermore, the showcase of folk culture in murals can realize the beautification function of the giant retaining walls. In addition, the SBE of giant retaining walls is also linked to coordination, where the walls embellished with the natural landscape and folk culture murals have better SBE performance than those with local stones. This study provides a reference for constructing scenic beauty after fulfilling the safety function of retaining wall engineering.

Jiuzhai Valley, a World Natural Heritage Site, was significantly damaged by an earthquake in 2017. However, case studies on the restoration of World Natural Heritage sites are lacking. This study aimed to use the box-counting method to analyze fractal characteristics of the terrain in Shuzheng Valley. Research data were used to conduct artificial intervention restoration of the earthquake-damaged terrain. Our results showed that (i) the travertine terrain shows self-similarity at different scales. The fractal dimension was related to terrain complexity: the more complex the terrain, the higher the fractal-dimension value; (ii) a combined form of fractal generator elements at the same scale was related to terrain complexity—differences in the spatial combination of the fractal generator elements can be compared based on fractal dimension; and (iii) the newly restored dam terrain also showed fractal characteristics whose spatial combination form was similar to that of the surrounding terrain. The complexity of the terrain’s fractal element combination may be related to the influence of surrounding environmental factors and the different ecological functional requirements. This study provides basic data for the near natural restoration of the Sparkling Lake travertine terrain after an earthquake and proposes new concepts and strategies for restoring World Natural Heritage Site terrains.

The transfer of CO2 from lakes to the atmosphere is a component of the global carbon equilibrium, while the quantification of the CO2 partial pressure (pCO2) is critical for exploring the contribution of freshwater CO2 emissions in the regional/global carbon budget. To investigate the daily variability of pCO2 and CO2 fluxes (fCO2), we conducted in situ biweekly pCO2 detection at 7:00, 10:00, 14:00, and 17:00 China Standard Time (CST) from Jan. to Sept. 2020 in the subtropical urbanizing Qinglonghu Lake in Chengdu, Sichuan, China. The pCO2 during the daytime varied greatly from 8.3 to 1,061.3 μatm, with an average of 137.7 μatm, while the average pCO2 (n = 11) clearly gradually decreased from 7:00 CST (204.9 ± 295.7 μatm) to 17:00 CST (93.5 ± 105.5 μatm). Similarly, the average fCO2 values were −19.3 (±27.5), −24.8 (±20.7), −29.2 (±9.1) and −30.4 (±10.7) mmol m2 h−1 at 7:00–17:00 CST, respectively. Further, we observed a negative correlation between pCO2 and water temperature and dissolved oxygen, but a positive correlation between pCO2 and total organic carbon and chlorophyll a. By a systematic overview of previously published data, we also discussed the differences and uncertainties in pCO2 and fCO2 estimates at regional and global scales. We therefore speculate that uncertainties may exist in the contributions of CO2 balance on lake surface in regional/global carbon budgets due to this daily pCO2 variation.

Dwarf bamboos are clonal plants with potential applications in the remediation of heavy metal-polluted soils, although their pollution adaptation strategies are unknown. This study examined the biomass allocation strategies and lead (Pb) enrichment characteristics of various dwarf bamboo tissues by the end of the growing season and explored their potential for phytoremediation of Pb stress in the soils. Six dwarf bamboo genotypes were treated with three levels (0, 300, and 1500 mg kg–1) of soil Pb stress. The majority of the bamboos adopted two biomass allocation strategies to adapt to Pb stress, namely, “reducing biomass allocation into new bamboo growth” and “increasing/stabilizing biomass allocation into rhizomes”. Pb accumulation was highest in the roots, rhizomes, and old stems and showed the following trend: rhizomes/old stems> new roots/old roots> old leaves> new leaves> new stems among various tissues. Moreover, the six bamboos used three different Pb-enrichment strategies, as follows: (i) “rhizome domination and old stem synergy” (Sasaella glabra (Nakai) f. albo-striata Muroi, Sasa auricoma (Mitford) E.G. Camus, Sasa fortunei (Van Houtte) Fiori, and Shibataea lanceifolia C.H. Hu); (ii) “old stem domination and rhizome synergy” (Indocalamus decorus Q.H. Dai); and (iii) “old stem domination and new root synergy” (Sasa argenteostriata (Regel) E.G. Camus). In Pb-contaminated soils, genotypes with TFs greater than 1 were Sasa fortunei (Van Houtte) Fiori, Sasa argenteostriata (Regel) E.G. Camus, and Indocalamus decorus Q.H. Dai; in addition, only S. argenteostriata had BCF values greater than 1. Furthermore, this study provides the first evidence that S. argenteostriata can extract 0.22 and 0.58 mgplant−1 of Pb ions in soil polluted with 300 and 1500 mg kg−1 Pb, respectively. S. argenteostriata showed the greatest potential for phytoremediation among the bamboo genotypes in both Pb-contaminated urban and mining sites.

Abstract Fargesia Franchet emend. Yi is closely allied with Thamnocalamus Munro but differs in many major morphological characteristics. Based on traditional morphological characters, it is difficult to differentiate these two genera. The current study measured 19 species in these two genera to determine whether variations in 12 categories of major characters are continuous. In addition, a self-organizing map (SOM) and cluster analysis were used together to reveal whether the known species of Fargesia represent discontinuous sampling of Thamnocalamus. The results show that 46 morphological characteristics exhibited high variation at the generic and species levels. In addition, the cluster analysis showed that 32 morphological characteristics of Thamnocalamus and Fargesia were divided between two species and well separated from the outgroup. Additionally, significant differences (P

Urban greenways are playing an increasingly important role in promoting green and healthy lifestyles. However, the correlation between the physical properties of greenways and user satisfaction is unclear, so the health benefits of greenways cannot be effectively brought into full play. To figure out what physical properties of the greenway affect the user satisfaction, an empirical study was carried out. Multiple linear regression is used to evaluate the users' satisfaction of 90 randomly selected samples of greenways in Chengdu. MATLAB visual numerical analysis is used to quantify the color values of the sample pictures. The results show that eco-belt greenways in Chengdu adopt a great variety of hues and are presented with medium saturation and medium brightness. Users significantly prefer red asphalt pavement for large-width greenways and non-asphalt pavement for small and medium-width greenways. The study finds that greenway widths and pavement colors (hue and brightness) are the main factors affecting user satisfaction. It is suggested that designers make differentiated designs for greenways of different widths in emerging urban communities. Large-width greenways are more compatible with red asphalt and moderate brightness due to broad space vision. Small and medium-width greenways are more congruent with non-asphalt pavement and moderate brightness. This study has positive significance for the user's satisfaction with urban greenways, greenway design and construction, environmental management, and the health and well-being of urban residents. [ABSTRACT FROM AUTHOR]

Chengdu with typical basin climate characteristics is located in the western part, Sichuan province, China. Its special topographic and climatic conditions often cause PM accumulation in urban area. Plants may play an important role in alleviating air pollution. A field experiment was conducted to investigate effects of leaf trait on particulate matter trapping of 12 plant species in urban roads, Chengdu. The traits of leaf shape and surface were qualitatively described in the experiment. PM content per unit leaf area and heavy metal element content per unit leaf weight were measured respectively.PM content per unit leaf area was significantly increased by rough leaf surface characteristic of hair or complex surface texture. Meanwhile, significant positive correlation between Cd and Hg content per unit leaf weight with PM content per unit leaf area was observed. These results partially supported our hypothesis. In addition, significant linear regression between ascorbic acid content and air pollution tolerance index of plant was observed. It was suggested that increase of ascorbic acid content enhanced tolerance of plants to air pollution. Finally, Loropetalum chinense, Osmanthus Jragrans and Aucuba japonica were recommended as adaptive plant for PM trapping in Chengdu. [ABSTRACT FROM AUTHOR]