Research On The Optimization Of Urban Park Space For Pollen Allergy

As an "oasis" in modern cities,city parks are important green open spaces for purifying urban air and for citizens to carry out various leisure activities,breathe fresh air,and get in touch with nature.However,in the planning and construction of urban parks,insufficient attention has been paid to the allergenicity of plants.Therefore,areas with high allergenic risk have also appeared in existing urban parks,which have caused harm to the health of recreational people.Xuanwu Lake Park in Nanjing is an important urban park in Nanjing.In this study,Xuanwu Lake Park was used as the research object,and the allergenic index of each area of the park was investigated using the measurement and calculation method of Urban Green Zone Allergenicity Index.The study found that the areas with high allergy risk in Xuanwu Lake Park are mostly distributed in the tourist a ctivity areas with large crowds and relatively concentrated,the number of allergenic plants in these active areas is more concentrated,and due to poor air mobility,pollen stays in the area for a longer time and the concentration is relatively higher.At the same time,the influence of the monsoon will also have a certain impact on the area of low allergy risk of the downwind.The study believes that although the use of non-allergenic plants to replace allergenic plants is the most effective measure to reduce the allergenic risk and reduce the harm to tourists,however,the existing plants in the city park have formed the unique forest canopy line and forest edge line.The park space created by the plants not only carries the memory of the city but also reflects the historical context of the city,Therefore,it is impossible to replace all the allergenic plants in the park in the space optimization of the city park.For areas with a large number of allergenic plants,more concentrated cultivation,poor air mobility,and temporarily unable to be replaced with non-allergenic plants,the layout of the park road should be optimized,the spatial elements should be adjusted,and the spatial function should be changed.Avoid arranging the garden road in the area where allergenic plants are concentrated and dense,and try to arrange it in the open space area adjacent to the grass or water.At the same time reduce the planting of sidewalk trees,strengthen the mobility of air to prevent pollen accumulation,reduce pollen reside nce time.The arrangement of garden chairs,stone benches and landscape sketches should be minimized under the allergenic plants to reduce the space elements that are easy to attract tourists to stay.Spatial functions such as leisure and entertainment,exercise and fitness,and picnics in high allergy risk areas should be changed for longer stays to reduce stay time and harm to tourists.At the same time,the use of hard paving should be reduced for park roads,squares and regional spaces located at the downwind of high allergy risk,add lawns and shrubs to reduce the updraft caused by the temperature differencebetween the hard ground and the air,and prevent the allergen pollen falling to the ground from re-diffusing into the air under the action of the updraft,thereby reducing the pollen concentration in the air near the ground,with a view to reducing the risk of allergies.New information technology methods of smart parks should be introduced,and on-site pollen concentration monitoring means should be used to remind visitors of pollen concentration coefficients in real time through multiple media,issue location information of areas with high allergenic pollen concentration to warn visitors to reduce the harm of allergic plants to tourists.The selection of allergenic plant varieties should be based on the principle of non-allergenicity,while taking into account the spatial function and the lands cape effect of the park.Use non-allergenic color-leaved plants.Manually pruning and watering allergenic plants that cannot be replaced at present to reduce the spread of pollen and achieve the purpose of improving the environmental quality of the park.Thereby creating a comfortable,restful and reassuring park leisure and recreation environment.