Relationship Between Microclimate Of Plant And Human Comfort In Five Parks In Hangzhou

With the acceleration of urbanization,urban heat island effect,as a prominent issue of climate change,has attracted the attention of scholars at home and abroad.How to alleviate the urban heat island effect,create a comfortable living environment,and meet people's requirements for the quality of life is an important topic of urban ecological environment construction.Urban green space is an important outdoor green space for tourists,which can effectively alleviate the urban heat island problem.It is also a research direction to study the influence mechanism of green space microclimate by numerical simulation method in recent years.Based on the micro scale observation of Microclimate Characteristics of plant communities in summer,autumn and spring,combined with numerical simulation,the microclimate effects of different plant community structures and their impact on human comfort were quantitatively analyzed,and the plant community configuration mode conducive to the improvement of human comfort was studied,which provided scientific basis for urban green space to minimize the heat island effect and provide a scientific basis for the city Green space planning and design provides feasible construction strategies to create a more comfortable and livable living environment.The main conclusions of this study are as follows:(1)At the micro scale,the daily mean change trend of air temperature in summer,autumn and spring was consistent,and the seasonal variation law of air temperature was summer > spring > autumn.The diurnal mean change trend of relative humidity in the three seasons was consistent,and the seasonal variation law of relative humidity was spring > summer > autumn.The variation trend of daily average light intensity in three seasons was consistent,and the plant community had better shading effect.There was no regular change of wind speed at different measuring points in three seasons,and the plant community had a certain wind protection effect.The change trend of daily average humidity and heat index(THI)in the three seasons was the same.The seasonal variation of human comfort was autumn >spring > summer,and plant community played a role in improving human comfort.Human comfort is negatively correlated with air temperature and positively correlated with relative humidity,but not with wind speed and light intensity.Plant community can improve human comfort mainly by reducing air temperature and increasing relative humidity.(2)The order of air temperature of different plant community structure in three seasons was tree grass > tree shrub > tree shrub grass,and the order of relative humidity was tree shrub grass > tree shrub > tree grass.The results showed that the tree shrub grass structure had a higher level of human comfort.The leaf area index was positively correlated with the cooling and humidification rate and the improvement intensity of human comfort,and was significantly correlated with the improvement intensity of human comfort.(3)At the micro scale,the correlation between plant community structure and the temperature and humidity effect of green space was quantitatively analyzed by numerical simulation.The results showed that: under high temperature conditions,the order of cooling effect was arbor shrub grass > arbor grass > shrub grass > grassland,and the maximum temperature difference of plant community with tree,shrub and grass structure was 0.71 ?.The results showed that the order of humidification effect was arbor shrub grass > arbor shrub > shrub grass,and the maximum humidity difference of plant community was 1.6% compared with grassland.The moisture and heat index thi of shrub grass community and grassland are basically the same,and the human comfort level is lower than that of arbor structure plant community.