Study On The Influence Of Campus Microclimate On Human Comfort And Its Improvement Strategy In Zhejiang A & F University

By analyzing the microclimate characteristics of campus green space in spring,summer,autumn and winter,this thesis takes the types of plants,water,buildings and pavement as the main factors affecting campus microclimate,collects the data of microclimate factors,and collects the information of green space plants with laser scanner.Excel,SPSS and Rayman software were used to quantitatively analyze the correlation between green space microclimate and human comfort level.Numerical simulation was carried out with ENVI-met software,and strategies for optimizing campus microclimate were proposed.The results of this study will provide data support for improving the microclimate environment of campus green space.The research conclusions of this thesis are as follows:(1)The results show that the shading effect and cooling and humidification effect of green space of different tree species on microclimate are different.The shading effect of pine and cypress trees,shrubs with large crown width and dense branches and evergreen trees with tall trunks is better,the shading effect of low shrubs is worst,and the shading effect of deciduous trees in spring and winter is worse.The higher the richness of the plant community,the larger the average height and canopy width of the tree,the larger the leaf area index of the plant community,and the more significant the cooling and humidification effect of the green space.Leaf area index was positively correlated with shading rate,cooling rate and humidification rate.In terms of shading effect,the shading effect of arbor green space in spring,summer and autumn was the best,and the shading rate of shrub and grass green space in winter was the highest.In terms of cooling effect,the tree-lawn green space in spring and autumn and winter had the best cooling effect,while the arbor green space in summer had the best cooling effect.In terms of the humidification effect,the tree-lawn green space had the highest humidification rate in spring,and the arbor forest had the highest humidification rate in summer,autumn and winter.All green space had the effect of weakening wind power.(2)The results show that the cooling and humidification effects of water body gradually weaken with the increase of the distance from water body,and vegetation coverage and plant community structure are the important reasons for the humidification of green space farther from water body.Among the four types of ground surface on campus,the ground temperature of soft ground such as grass is lower in spring and summer,that of wood is lower in autumn and winter,and that of granite and square brick is higher in four seasons.(3)The simulation study shows that the air temperature and wind speed in summer are as follows:the average distributed green space and the centralized distributed green space < the natural distributed;Winter air temperature: centralized distributed < mean distributed green space and naturally distributed green space;Relative humidity and wind speed: centralized distributed > average distributed green space and naturally distributed green space.Three different ratios of shrub,shrub and grassland were simulated,and it was concluded that the community with the ratio of shrub,shrub and grassland at 1:6:20 in summer had better cooling and humidification effect on the green space and the ability to reduce wind speed.In winter,the community with the ratio of shrub,shrub and grassland at 1:3:15 had better humidification effect on the green space environment,and the community with1:6:20 had better ability to reduce wind speed on the green space.(4)The simulation results show that the relative humidity of the water body between the two greenbelts is higher and decreases to the northwest and southeast,while the relative humidity of the water body farther away from the greenbelts is lower.The simulation results show that the air temperature is lower and the wind speed is higher on the north side of the determinant building layout in winter and summer.The air temperature and wind speed in the atrium space of the enclosed building layout are lower.When about 10% of the hard paved ground area is replaced by grassland,the high temperature area is obviously reduced.When 10% of the woodland area is added,the high temperature area is reduced,and the humidity is also increasing.(5)According to the above conclusions,attention should be paid to the selection of shade tree species in campus green space,and plants with high tree height,crown width and leaf area index can be appropriately added.At the same time,appropriate proportions of trees,shrubs and grasses can be selected to enrich the hierarchy of plant communities.Deciduous trees can be planted on the northwest side of the water body.The orientation and layout of the building should conform to the dominant wind direction of the season;In the choice of campus construction ground type,can choose to set grass,or soft and hard combined underlying surface,improve the outdoor human comfort.