No abstract

During the COVID-19 outbreak, college students experienced different periods of isolation on campus, which has had an impact on students’ mental health. Based on ART theory, this study randomly selected students at Northwest A&F University, Shaanxi, China and distributed questionnaires in order to evaluate the psychological recovery effect of campus environment during the epidemic. The results showed that: (1) There were significant differences in the psychological restoration of four types of campus environments. Blue space had the greatest effect, followed by green space and sports grounds, while grey space had the least. (2) Time of stay had a very significant impact on psychological restoration. Longer time of exposure is not necessarily correlated with a better recovery experience. (3) In the different campus environments, extent is easier to be perceived followed by fascination and compatibility, and the weakest is being away. At the time of stay level, no significant difference was found in the perception of compatibility. Time of stay was negatively correlated with fascination and compatibility. These findings can provide theoretical and practical bases for campus environmental planning and construction following the COVID-19 epidemic.

With the acceleration of urbanization and industrialization, air pollution is becoming one of the most serious problems in cities. Urban green spaces, as “green infrastructure”, are an important part of urban ecosystems for air purification. Therefore, 10 typical green spaces of urban parks in the city of Xi’an, China, were selected as study areas according to vegetation structure and species composition. Considering meteorological factors and time changes, the effects of the selected green spaces with different vegetation structures of different heights on the reduction in airborne particulate matter concentration were explored. The results showed that the following: (1) Temperature, relative humidity, wind speed, and air pressure had significant correlation with the concentration of airborne particulate matter at the different heights, and the correlations were the same at 1.5 and 5 m. (2) After heating in winter, the concentration of airborne particulate matter with different particle sizes increased significantly. The concentration of airborne particulate matter showed different trends throughout the day, and the small particles (PM1 and PM2.5) had a trend of “lower in the morning and evening, and higher at noon”, while the large particles (PM10 and TSP) gradually decreased over time. (3) In the selected green spaces with different vegetation structure types, the concentration of airborne particulate matter below the canopy (1.5 m) was generally higher than that in the middle of the canopy (5 m), but the effects of reducing the concentration of airborne particulate matter were consistent at the different heights. (4) The adsorption capacity of PM1 and PM2.5 concentration was strong in the partially closed broad-leaved one-layered forest (PBO), and poor in the partially closed broad-leaved multi-layered forest (PBM). Partially closed broad-leaved multi-layered forest (PBM) and partially closed coniferous and broad-leaved mixed multi-layered forest (PMM) also had strong dust-retention effect on PM10 and TSP, while closed broad-leaved one-layered forest (CBO) had a poor dust-retention effect. The results showed that the reduction effects of urban green spaces with different spatial structures on air particles were different, and were restricted by various environmental factors, which could provide a theoretical basis for the optimization of urban green space structure and the improvement of urban air quality.