Using social media data to explore the impact of green spaces on physical activity and sentiment in China:A systematic literature review

Social media data offers invaluable insights into the crucial role that green spaces play in promoting physical activity and sentiment. This study systematically reviewed the scientific evidence exploring the influence of green spaces on physical activity and sentimental states based on social media data. Overall, 8842 studies were identified through searching PubMed, Web of Science, Scopus, and CNKI databases up to December 30, 2023. Forty studies met the inclusion criteria for this systematic review. The analysis of the included literature revealed that the physical attributes of green spaces-such as accessibility, area of green spaces, natural landscape features and quality, types of greenery, visibility of green spaces, and the Normalized Difference Vegetation Index are correlated with the expression of positive sentiments among residents or significantly enhance residents' physical activity. The research unveiled the profound impact of multidimensional factors on the green space experience, including gender, age, geographic location, individual needs and preferences, seasonal variations, and socioeconomic backgrounds. Additionally, thermal adaptation and the frequency of park visits serve as mediating factors in the relationship between green spaces and sentiment or physical activity. Although this study provides important insights into the associations of green spaces on physical activity and sentiment, it faces limitations such as reliance on a single data source and the lack of geographic universality. In conclusion, green spaces significantly enhance physical activity and improve sentimental states across populations. Analysis of social media data facilitates a nuanced understanding of public behaviors and attitudes toward green spaces. Using advanced data analysis techniques is essential for a deeper comprehension of the dynamic interplay and underlying mechanisms that shape the impact of green spaces on physical activity and sentiment. Future research should prioritize the integration data from various platforms and the implementation of longitudinal studies.

Mapping perceived sentiments in university campuses with varied landscape metrics and climatic conditions

A sustainable university campus should accommodate students to experience positive emotions, which can be evoked by sustainable landscape with green and blue spaces (GBS). This effect is location-dependent because local vegetative type is climate-determinative, but evidence is not sufficient for sentiments of people experiencing campus landscapes. Forty-seven university campuses were selected along a latitudinal gradient in mainland China, and 100 subjects were chosen per campus (50 indoor and 50 outdoor). Photos of the subjects' faces on Sina Weibo were collected. Facial expressions were assigned happy, sad, and neutral scores (n = 4,334). The average temperature (AveT) and blue space area (BlueA) showed negative relationships with latitude, thereby generating neutral emotion scores for subjects at indoor and outdoor locations. The ratio of green space area to host campus was the only landscape metric that depressed the presentation of happiness and enhanced sadness levels. Large water bodies should be built on campuses to induce calmness, and a high ratio of green spaces should be avoided. Mapping results show that campuses in eastern regions (Beijing and Liaoning) tend to elicit positive sentiments more frequently.

Joint effects of air PM2.5 and socioeconomic dimensions on posted emotions of urban green space visitors in cities experiencing population urbanization: A pilot study on 50 cities of East China

People may perceive and expose negative sentiments in days with PM_2.5 pollutions, but evidence is still insufficient about the joint effects of PM_2.5 and socioeconomic factors on human sentiments. In this study, a total of 8032 facial photos of urban green space visitors were obtained from Sina Weibo in 50 cities of East China and rated for happy, sad, neutral scores and net positive emotion index (NPE; happy minus sad). Seasonal air PM_2.5 concentrations were collected from days when people exposed faces in cities that were categorized to medium, large, outsize, and mega sizes according to resident populations (RPs). In summer, people posted lower sad score (11.28 %) than in winter (13.51 %; P = 0.0357) and higher NPE (35.86 %) than in autumn (30.92 %; P = 0.0009). Multivariate linear regression on natural logarithms revealed that factors of gross domestic product per capita (parameter estimate: 0.45), RP (0.59), non-production electricity consumption (0.34), and length of road transport (0.34) together generated positive contributions to posted happy score, while the total retail trade of consumer goods (-1.25) and PM_2.5 (-0.50) were perceived as joint depressors on NPE. Overall, cities with more rich households and activated retail sales attracted more people who exposed smiles in weathers with PM_2.5 compared to cities where local economy is reliable on heavy industry. The summertime in mega cities will be recommended to enjoy a higher frequency to perceive satisfaction due to exposure to low PM_2.5.

Interactive climate-soil forces shape the spatial distribution of foliar N:P stoichiometry in Vaccinium uliginosum planted in agroforests of Northeast China

In regions with a ban on forest logging, fruit-bearing shrubs are favored as an alternative source of ecological products over the harvesting of timber. The introduction of cultured shrubs from their habitat to newly developed lands has to be decided according to nutrient availability. Foliar nitrogen (N) and phosphorus (P) stoichiometry is an easily measured and reliable parameter to quickly indicate possible limits in imbalanced N-P availability. When attempting to create a spatial distribution map of the foliar N:P ratio in an objective shrub species, it is helpful to first explore its potential acclimation to the N:P imbalance caused by the joint forces of soil property and regional climate. This study evaluated the cultivated populations of Vaccinium uliginosum in northeastern China's agroforests, using Vaccinium uliginosum as a model shrub species. A total of 51 populations were selected from 51 managed stands, of which 34 were in forests and 17 on farmlands. Foliar N and P concentrations, soil physical and chemical properties, and topography were investigated in 2018, and regional climatic factors were assessed by averaging previous 5-year records (2013–2018). V. uliginosum was determined to have a foliar N:P ratio lower than 4.4, which can be characterized as a limit of N relative to that of P. On forested lands, soil pH negatively impacted regressed foliar N:P, which was also part of the contributions of soil total P content and average temperature to foliar N concentration. On farmlands, low soil pH also resulted in a reduced foliar N:P ratio with joint contributions of ammonium N, nitrate N, and available P contents in soils and air humidity. Spatial interpolation indicated that western forests could benefit from introduced V. uliginosum with a higher foliar N concentration, while the introduction to eastern farmlands can lead to a higher foliar N:P ratio up to 14.6. Our study demonstrates recommended locations with expected soil and meteorological conditions by mapping spatial distributions, which can be referred to by other species and regions.