Study On The Classification And Stress Resistance Of The Three-dimensional Green Plants In Haikou City

With the acceleration of the urbanization process,the problems of population,resources and the environment have become increasingly prominent.Three-dimensional greening scheme is a scheme with significant advantages in ecology,economy and art,which has been widely promoted in the shortage of urban land resources.But at present,the focus of urban three-dimensional greening is still focused on the open Spaces such as road sections,squares and parks,while the three-dimensional greening of residential areas starts late and develops slowly.In view of the situation of promoting the construction of energy-saving gardens and livable city in China,this paper studies the three-dimensional greening plant landscape of residential green space,evaluates its current situation,and discusses the widely used greening mode and plant application types,in order to provide reference for the three-dimensional greening construction of residential area.At the same time,in order to improve the utilization efficiency of residential green space and improve the ecological environment,the resistance of three kinds of green plants will be studied.This study carries out field investigation and evaluation on 8 residential areas developed and constructed in Haikou city after 2015,aiming to explore the current problems of three-dimensional greening construction of residential areas in Haikou city,and puts forward reference solutions.The study results are as follows:1.The residential area can adopt five types of three-dimensional greening methods: roof greening,corridor greening,hedge greening,wall greening and windowsill greening.In the process of field investigation and data collection,it was found that the plant life types in Haikou residential district were very rich,including different types of trees,shrubs,bamboo,vines and herbs.Among trees,shrubs and woody vines,evergreen plants represented 82.61%,while deciduous plants represented only 17.39%.This suggests that evergreen plants are more suitable for three-dimensional greening,because they can make the area evergreen and meet people’s needs for the plant environment.2.A total of 219 kinds of plants were used for three-dimensional greening,and 17 kinds of trees,85 kinds of shrubs,44 kinds of vines,66 kinds of herbs and 7 kinds of bamboo were used in 42 sample sites.Shrubs and herbs occupy a relatively large proportion.Further classification of plants revealed that most of them belonged to Rosaceae,Jingaceae and Poaceae.Longxing Apartment,Renheng Binjiang Park and Jiayuan-Riverside Jinyu are the top three residential areas in the use of three-dimensional green plants.The most extensive form of greening,namely the roof greening.Among them,vine rose,velvet crape myrtle and Begonia with good ornamental effect and stress resistance were selected as test materials,and the physiological resistance of the three plants were studied by measuring the physiological and biochemical indexes under high temperature,drought and pollution stress.3.High temperature resistant physiological determination,based on the relative conductivity,MDA content,soluble protein content,SOD,POD activity five resistance identification index,the heat resistant physiology of test material,the study found that different plants under stress of different physiological differences,with the extension of the stress time and the increase of temperature,the change of the physiological index trend and amplitude is different.The relative conductivity,MDA content,soluble protein content,SOD and POD activity were significantly correlated with the high temperature treatment,while the relative conductivity,MDA content,SOD and POD activity were all positively correlated with the high temperature treatment process,while the soluble protein content had both positive and negative correlation.Based on the changes of various indicators,the experiment concluded that the selected plants had heat order: velvet crape myrtle> four seasons begonia> rattan rose.4.Under drought stress,combined with the soil water content,plant form and leaf water content evaluation of the selected plants of drought tolerance,velvet crape myrtle under drought stress still has good plant form,leaf water content and soil environment water capacity,in the selected three kinds of plants have good drought resistance,this is consistent with the study of heat stress,so the test that velvet crape myrtle is greening plants,can have good physiological state and performance under drought and high temperature conditions.5.Under anti-pollution stress,SO2 stress tests were conducted on three green plants to observe their phenotype,and comprehensively evaluate the resistance to SO2 with physiological indexes such as relative conductivity,MDA,CAT activity and p H value.The experiment shows that the seasonal Begonia has an ideal phenotype and physiological state under the stress of SO2,and has a strong resistance to the environmental conditions of high SO2.Therefore,the seasonal begonia is suitable for planting in areas with serious environmental pollution.