Effects Of PM_2.5 And PM₁₀ In Plant Communities In Chengdu Living Water Park Under Different Weather Conditions

After the 18th national congress of the communist party of China（CPC）,the construction of ecological civilization as an important part of the overall layout of the"five elements"is the first time that the construction of ecological civilization has become a popular word for the people.In recent years,the smog in chengdu has been frequent,and garden plants can effectively reduce the concentration of particulate matter and play an indispensable ecological role through the effect of dust removal.What kind of weather and time period is more suitable for tourists to travel is not yet decided,how to scientifically and rationally design and build garden plant community,to give full play to its stagnant effect,urgently needs to be solved.Based on the chengdu living water park as an example,in a sunny day,cloudy and cloudy days after the rain weather conditions,through the different approaches to campus structure types xerophytes and aquatic plant community PM_2.5 and PM₁₀ from7:00 to at 19:00,the results showed that:（1）There was no significant difference between PM_2.5 and PM₁₀ daily concentration in sunny days and cloudy days,and the cloudy days after rain were significantly lower than those of the previous two,but the test values were significantly higher than that of the national control points in chengdu.In sunny days and cloudy weather,the concentration of particulate matter in the park will be high in the morning and evening,and at noon,the lowest value will be at 13:00.In the cloudy days after the rain,the concentration of particulate matter continued to decline.（2）The purification effect of plant community on PM2.5 and PM10 showed a high noon and a low trend in the morning and evening.（3）Under cloudy and sunny weather,the differences in PM_2.5 dust reduction rate among different xerophytia were as follows:Tree-Grass Plant community structure was the best,Tree Plant community structure was the second,Grass Plant community Tree-Shrub Plant community,and Tree-Shrub-Grass Plant community are negative and Tree-Shrub-Grass Plant community is the worst.The difference of PM₁₀ dust reduction rate among different community structures was as follows:the dust reduction rate of the Tree-Shrub-Grass Plant community was the highest,Tree-grass Plant community was the second,Grass Plant community was the lowest,and all had positive values.After cloudy days,the PM₁₀ and PM_2.5 dust-reducing rates were highest in Tree-Shrub-Grass Plant community,followed by the Tree-Grass Plant community and Grass Plant community is lowest.（4）The aquatic plant community also has a remarkable ability of dust removal,which is a vacuum cleaner to reduce dust in the water environment,and it is quite water-floating complex community,which is more than a single water type.（5）Oarticle mass concentration is correlated with temperature,light intensity and air pressure,which is positively correlated with humidity and traffic flow,and has no significant correlation with noise.It is suggested that people’s leisure time should be chosen in the afternoon,and the weather after rain is the ideal weather for recreation.Landscape designers and managers in designing and building community space,should pay attention to scientific planting density,keep colony forming suitable crown density and horizontal permeability,recommend building Tree-Grass Plant community or Tree-Shrub-Grass Plant community.The aquatic plants in the future can continue to common dust effect research,in some serious atmospheric pollution of water environment by configuring high efficiency dust detention of aquatic plant community to improve air quality.