Preliminary data on effects of different street vegetation on stress recovery

Streets are important public spaces in daily life, and their stress-relieving abilities help to improve people’s physical and mental health. To investigate the effects of different types of street vegetation on people’s stress recovery, this study used virtual reality technology to establish five street scenes with different vegetation types, including a non-vegetated street, a street with trees, a street with trees and grass, a street with trees and hedges, and a street with trees, grass, and flowers. Twenty-four participants completed the Trier Social Stress Test and then watched the five street scenes for stress recovery. Participants rated the vegetated streets as significantly better at reducing stress than the non-vegetated street. Compared with the non-vegetated street, the participants’ POMS scores decreased by 2.59–12.09 and ROS scores increased by 0.83–3.67 after watching the vegetated streets, indicating significant improvement in mood ( P < 0.001). HRV data showed that the combination of trees, grass, and flowers was the most effective for stress recovery (LF/HF = 0.67 ± 0.42; pNN50 = 27.41% ± 16.32%). EEG data showed that participants’ alpha power was 0.05–0.66 µV 2 higher and mental stress scores based on brainwave power were 0.23–0.37 points lower in the vegetated streets than in the non-vegetated street. The occipital and frontal regions showed the most positive responses to changes in vegetation elements, and alpha brainwaves in the O2 channel were the most active. Therefore, the streets with vegetation were more conducive to stress recovery than the non-vegetated street. It is thus suggested to integrate trees, grass, flowers, and other vegetation types along streets.