Conservation Methods And Theoretical Studies Of Plants And Landscapes In Urban Environment

With the development of society,the environment of human existence and even the whole ecological environment system are constantly changing.In particular,the development of industrialization and the acceleration of urbanization.People gradually settle in cities,which leads to a series of problems,such as urban land,air,water pollution and heat island effect.Otherwise,greening can improve the quality of urban environment to a certain extent,such as beautifying the urban landscape,improving the urban ecological environment,adjusting the local microclimate of the city and so on.These are of great significance to the promotion of urban development.Landscape plants are one of the garden elements,which have functions of purifying air,preventing dust and noise,and improving local climate.In addition,landscape plants are the materials that constitute the color environment.They have many kinds and different postures.According to the changes of tree posture,leaf color and flower and fruit season,the beautiful scenery is formed,giving people a sense of beauty in many aspects.Therefore,the rational use and maintenance of plants to create landscape can not only provide and produce ecological effects beneficial to human survival,but also bring rich artistic experience to people.The ancient capital of Nanjing has a superior natural environment.It is also a historical and cultural city.During the past 30 years of reform and opening up,Nanjing has attached great importance to urban greening and made outstanding achievements in the field of environment.As the development of city,landscape plants are playing a more important role in city and ecology,but the pressure of conservation in later period is also become increasingly prominent.In the field research,it was found that most of the plant types in Nanjing were single,and the greening function of the street trees was insufficient.The phenomenon of "lack of seedlings" and "dead seedlings" has appeared many times,and the phenomenon of pests and diseases is serious.Therefore,Nanjing needs to improve its scientific and artistic aspects in the allocation of garden plants and the management of maintenance.Based on the field survey of urban plant landscapes in Nanjing,this study records the plant species information,geographical location,growth status,plant community collocation,conservation management mode and ecological effects according to the urban green space classification criteria.According to the investigation,there are 48 species of plants in Nanjing,including Ficus sylvestris,Siraitia grosvenorii,Liquidambar formosana and Photinia fragrans.After the on-the-spot investigation,the data was collated,and the comprehensive evaluation method of green plant landscape in Nanjing was established by using the research method of Analytic Hierarchy Process(AHP)Through comprehensive evaluation and consideration of the five aspects of ecology,environment,function,value and appreciation,a comprehensive evaluation model of plant landscape conservation was established,and its differential function was evaluated from the perspective of plant landscape quality.This study summarized the development,problems and protection measures of modern urban plant landscapes by means of literature research,case analysis,analysied and summarized,etc.,then referring to the domestic and international plant landscape research review and related theories.After completing the above research process,in order to improve the maintenance quality and grade level of green space,create a city landscape that respects nature and local characteristics,and constantly improve the green space system of Nanjing,the strategies and projects of optimizing and upgrading for the construction of sustainable ecological garden city are put forward from the perspectives of conservation methods and maintenance and nursing theory.