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• The urban 3D greenery volume is below the minimum limit set by the 2D indicators in the greenery regulations. • The GVI of 30% that can be used as a preliminary standard reference. • The central greenery belt and the Tree-Shrub structure are critical to improve the GVI. • Roads with 4-bar pattern have the greatest potential for GVI enhancement. • To improve the GVI, the shrubs, rather than the complete vegetation structures, should be applied first to roads. Urban streetscapes play a critical role in ecological benefits and resident health. The green view index (GVI) can improve the limitations of the existing road greenery index, which is too planarized. This study used road patterns and vegetation structures to explore the intrinsic connection and application possibilities between the GVI and the urban road greenery indicators. The study acquired and then selected 27,038 valid street images to calculate the GVI through semantic segmentation, and used ArcGIS10.6 to calculate the greenery land ratio (GLR) and greenery coverage ratio (GCR) for 593 roads. After strictly controlling of the variables, typical roads were selected for simulation scenario comparison experiments. The results indicates that the GVI will be lower than the greenery volume of two-dimensional indicators, and a threshold within 30% can be set as a preliminary reference of the GVI standard for urban streetscapes. The GVI is irreplaceable and has a more flexible range, which provides a more comprehensive, accurate and rigorous evaluation of the greenery volume. The central greenery belt and the shrub layer are essential to enhance GVI. From all researched viewpoints, the Tree-Shrub and Tree-Shrub-Herb structures have similar GVI values. The roads with the 4-bar pattern have the greatest potential for GVI improvement. The impact of the divided greenery belts to affect the GVI may lower than the central greenery belt. In addition, the arbors are critical in enhancing the GVI, but for roads in the early stage of construction or when aiming to improve the GVI level, the application of shrubs should be considered first rather than the perfection of the vegetation structure. This study verifies the necessity of utilizing the GVI to improve the urban greenery index system and provides a quantitative reference for the practical application of the GVI, constructive comments on the greenery volume construction of urban streetscapes, and future research directions for the GVI. [ABSTRACT FROM AUTHOR]

• Ta and RH at each parking lot is similar while Tg, Ts, and Tmrt differ significant. • Cooling effect of trees is stronger than shading devices for the same shaded area. • The structure and the mesh did not improve Ta and RH. • The combination shade of trees and mesh enhanced thermal benefits. • Grass can reduce the Ts and weaken the negative effects of the mesh on Ta. The conventional surface parking lots lead to prominent urban thermal environment problems. Therefore, it is important to explore the design form of the parking lot that can generate more thermal benefits. In this study, we compared the differences in the thermal environments of eight common urban parking lots in Hangzhou, China, and analyzed their main influencing characteristics. Results show that air temperature and relative humidity differed little among the studied parking lots, with the maximum mean differences during the daytime being only 0.7–0.8 °C and 3.2–3.3%, respectively; however, the globe temperature, surface temperature, and mean radiant temperature had significant differences, with the maximum mean differences of 11.6, 10.6, and 13.6 °C, respectively. Among the factors, shade had an important effect on the thermal environment of the parking lot. We found that the cooling effect of trees was stronger than that of shading devices for the same shaded area. In addition, the combination of trees and mesh enhanced thermal benefits and has great application prospects, especially for the low coverage trees. Increase in grass cover can weaken the negative effects on the air environment of the mesh and more effectively reduce the surface temperature. [ABSTRACT FROM AUTHOR]

• The most suitable scene for the human brain is a VGI of 60% to 80% with a three-layer vegetation structure. • A VGI of 60% can be used as a VGI grading indicator. • Residential landscape has the most significant effect on weakening delta and theta. • The two-layer vegetation structure with a VGI above 80% can have the greatest instantaneous weakening effect. Visible Green Index (VGI) reflects the degree of greening from human vision to affect human health and well-being that has gradually become a new type of urban green space index. But few studies show how human reacts to VGI under different vegetation structures. This study designed and conducted an experiment to evaluate human's response to scenes which were panoramic pictures of residential green spaces and projected by Virtual Reality. Participants (n = 97) were asked to do deep breath training and then they immersed in the VR experience of three groups scenes with different VGI and vegetation structure for five minutes, during which we collected Electroencephalography data, which indicated that the most suitable scene for human brain is a VGI of 60% to 80% with a three-layer vegetation structure by multiple comparisons. But the two-layer vegetation structure with a VGI above 80% can have the greatest instantaneous weakening effect. Besides, residential landscape is most significant in reducing brain waves of delta and theta, and we propose that a VGI of "60%" can be used as a VGI grading indicator. The study provides a certain theoretical basis for the landscape planning of residential areas, which is helpful to improve the theory of VGI and promote its establishment as a new type of urban green spaces indicator. Our findings also further verify the relationship between landscape and human health. [ABSTRACT FROM AUTHOR]

With the development of botany and urban greening, Europe and the United States have conducted extensive collections of urban greening plants worldwide especially in China. Because of its unique ornamental value, economic significance and ecological benefits, bamboo has become the main collecting target in China and has been widely introduced to the United States. Studying the history of introduction of bamboo is vital for understanding bamboo's redistribution and application in urban green space. Through a large number of literature reviews and extensive field investigations, we verified the scientific names of bamboos introduced from China to the United States, re-investigated the introduction places and dates, and counted the number of existing bamboos in the United States in an attempt to clarify the history of bamboo introduction from China to the United States and its application in urban greening. From 1898 to 2010, the bamboo introduced from China to the United States belongs to 29 genera (accounting for 85.3 % of the genera in China), 185 species (34.8 % of the species in China), 13 varieties, 20 forms, and 25 cultivated varieties. The bamboo was collected from 21 provinces, municipalities, autonomous regions and special administrative regions, almost covering the natural distribution area of bamboos in China. According to Inventory of Seeds and Plants Imported and Plantae Wilsonianae , 11 people have collected bamboo directly in China with McClure, Meyer and Wilson playing key roles. The time period of this research about bamboo introduction history spanned approximately 110 years with the main period centered from the 1900s to the 1940s, which affected by the historical background of the world especially China. Our research helps to get a better understanding of the bamboo, promotes its application as an ornamental in urban greening, and further boosts the integration of plant landscape diversity with plant culture. [ABSTRACT FROM AUTHOR]