Study On The Ecological Benefits And User Evaluation Of The Riverside Scenic Belt In Nanjing Hexi

With the development and progress of society,urban parks and green spaces are not only an indispensable part of people’s lives,but also an important indicator of civilized cities and ecological garden cities.Since the 21st century,China’s urban construction has developed rapidly,and also urban landscape construction.The number and scale of urban parks are increasing day by day.However,at present,most of the parks focus their planning design and construction on the creation of landscape beautification effect and recreational space for tourists.It makes man-made landscape completely replace the natural landscape,and urban parks serve as stages for flower display and tourist attractions.It is difficult for people to feel the real pure natural landscape,and the ecological benefits of urban parks are ignored.As an important part of the planning and construction of Nanjing Hexi New town,the riverside scenic belt in Nanjing Hexi is a major landscape ecological corridor for the construction of the city along the river.The construction of the scenic belt started in 2004.Through continuous improvement and upgrading,by 2014,the 11km coastline along the Yangtze Rive inr Hexi section has changed from the original urban-rural junction,andstone yard,dock and other disorderly plots into urban parks with green fields,beautiful environment,birds’ songs and flowers,and has become a model of urban construction along the river in the whole country.This not only promotes the development of urban construction in Hexi area,but also greatly improves the urban environment along the river.Taking the Hexi riverside scenic belt as a whole green corridor as the research object,the paper discusses the landscape environmental benefits,ecological benefits and social benefits brought by urban park green space from four aspects:microclimate,air purification,water purification and biodiversity.The paper chooses Nanjing hexi riverside scenic belt as a study case,and analyzes the ecological benefits and user evaluation of the belt from measured data and user perception.The measured data mainly include temperature and humidity data in winter and summer,PM2.5 and PM10 data in air,oxygen content,total phosphorus,total nitrogen,ammonia nitrogen and permanganate index in water quality,observation of animal and plant in the park.User perception is mainly based on questionnaire for tourists and local staff,which mainly includes microclimate,air purification,water purification and ecological diversity protectionThe results show that(1)The temperature and humidity regulation of urban ecological parks on regional microclimate is significant.In summer,the temperature of the green space environment with tree,arbor-shrub and arbor-shrub-grass structure is significantly lower than that of the control point,among which the adjustment of temperature and comfort by tree-grass structure is the most obvious.The most popular structure for users is the shade lawn,which is cool,well ventilated and comfortable.From the perspective of microclimate regulation,the green space construction of urban ecological parks should arrange reasonable evergreen and deciduous tree species,reduce canopy density and middle plant quantity,and use the underlying surface with high permeability.(2)Plants in urban parks have obvious purification effect on air pollutants.Different green space structures have different ecological benefits of air purification,and the structure with arbor-lawn as the main body has better air purification capacity.The majority of users think that the air quality of the riverside scenic belt is good and fresh,and the air quality of woodlands with dense shade is considered to be the best.To achieve the goal of upgrading air quality,we should reasonally allocate plant community structure and choose more suitable tree species in urban ecological park.Considering the growth law of different kinds of plants,we can promote carbon fixation and oxygen generation to optimize the ecological benefits.(3)The water system of the urban ecological park has good water quality,abundant aquatic plants,relatively humid regional microenvironment,good air mobility and high body comfort.Through comparison,it can be seen that the contact with soil,adaptive algae and other aquatic plants play a positive role in the purification of water quality.The majority of users think that the quality of water in riverside scenic belt is good and clean.The effective measures to improve the quality of water system of the park are giving play to the water purification function of natural wetlands,adjusting measures to local conditions,carrying out artificial water treatment,using ecological embankment,and strengthening the publicity of ecological science popularization.(4)Hexi riverside scenic belt has high green coverage,diverse plant communities and reasonable ecological allocation.After investigation,there were 386 species of common plant belonging to 226 genera and 104 families,and 17 species of common birds.Most users can see birds,reptiles,fish and insects in the park,and understand the ecological functions of green spaces.The principle of close to nature is adopted to protect the plant community environment and build diverse plant growth environment.The measures of developing scientific park plant protection,using native species reasonably and new species carefully,constructing scientific and reasonable plant communities and promoting positive succession can protect wild plants effectively.The measures of strengthening water protection and providing clean water for animals,strengthening habitat construction,controlling domestic animals,strengthening wildlife protection publicity and so on can protect wildlife effectively.The paper also puts forward the deficiency in how to balance the protection of ecological environment with the interference of human activities and tourism development,which still needs a more multiaspect and multilevel research.