Function Alanalysis And Ecological Evaluation Of The Dominant Landscaping Tree Species In Fuzhou City

Highways,as the entrances and exits of cities,are important carriers for displaying the city’s image,and they have functions such as ecological protection,characteristic landscapes,corridors,and educational culture.In this paper,10 kinds of common landscaping plants for Fuzhou Road(Bycle Michelia alba DC,Bauhinia purpurea Linn,Ficus microcarca Linn.f,Cybainsignis,Terminalia neotaliala Capuron,Sophoraxanthantha,Cinnamomum camphora(L)Presl,Lagerstroemia indica L,Erythrina crista-galli Linn,and Prunus cerasifera Ehrhar f)have the leaf functional traits,dust-retaining capacity,ability to retard particle size,and ability to adsorb different heavy metal elements.Screening highway greening tree resources with strong ecological purification ability,promoting urban forestry development and creating a favorable road ecological environment to provide scientific data support.(1)There were differences in leaf traits of ten common Fuzhou highway landscaping tree species,among which leaf carbon content had the smallest difference,the extreme value difference was 1.4 times,and the specific leaf area difference was the greatest.The extreme value difference was 2.6 times.There was a correlation between leaf traits of the 10 common landscaping tree species investigated in Fuzhou.The specific leaf area(SLA)of leaves was significantly negatively correlated with leaf dry matter(LDMC)and positively correlated with leaf nitrogen content(LNC).There was a significant negative correlation between carbon/nitrogen ratio(C/N).The leaf carbon content(LCC)was significantly negatively correlated with the leaf phosphorus content(LPC)and was significantly positively correlated with the ratio of nitrogen to phosphorus(N/P)and carbon/nitrogen ratio(C/N).The carbon-nitrogen ratio(C/N)was significantly negatively correlated with leaf nitrogen content(LNC)and leaf phosphorus content(LPC).(2)There are differences in the dust-retention abilities of 10 plants in different seasons.The seasonal regularity of the dust-retention abilities of most plants(except for Sophora xanthantha and Bauhinia purpurea Linn)is summer>spring>winter>autumn.Through cluster analysis of SPSS,the dust-retention abilities of the 10 species of plants can be roughly divided into four categories,with the strongest is Sophora xanthantha 3.43 1 g/m2,followed by Lagerstroemia indica L,Terminalia neotaliala Capuron,and Ficus microcarca.Linn.f.Their dust retention capacity is Between 1.515 g/m2to 2.34 g/m2,followed by Cinnamomum camphora(L.)Presl,Erythrina crista-galli Linn,Prunus cerasifera Ehrhar f,and Ceiba insignis,their dust-removing capacity is between 0.77 g/m2 to 1.149 g/m2,and finally is the Michelia alba DC and Bauhinia purpurea Linn.Their dust holding capacity is less than 0.5 g/m2.Through the analysis of the differences in the microstructures of the 10 plants,it can be seen that the dust-retention capacity has a certain relationship with the number of stomata,the degree of surface folds,and the density of the coat,but it is not absolute.(3)Sorts of TSP Average Adsorption Amount of Four Plants in Four Seasons Autumn>Summer>Spring>Winter,the ranking of PM10 average adsorption amount is spring>summer>autumn>winter,and the order of PM2.5 average adsorption was spring>summer>Autumn>Winter.However,there were differences in different types of granular particles adsorbed in different seasons.In the spring and autumn,the highest amount of TSP absorbed by the tree species is Sophora xanthantha,which is 0.44g/m2 and 2.248g/m2,respectively.In the summer,it is the Bauhinia purpurea Linn plum is 0.754 g/m2,and in the winter,it is Michelia alba DC,0.1 g/m2.From the perspective of PM10,the most adsorbed plant in spring is Lagerstroemia indica L 0.724g/m2.In summer is Prunus cerasifera Ehrhar f.0.774g/m2.In the fall,it is Erythrina crista-galli Linn 0.28g/m2,and 0.043g/m2 of Bauhinia purpurea Linn in the winter.From the point of view of PM2.5,the plants with the highest adsorption capacity in spring,summer and autumn were Sophora xanthantha,which were 2.534 g/m2,1.487 g/m2,0.501 g/m2,and 0.59 g/m2 in winter.The tree species with the strongest adsorption capacity of PM2.5 in the four seasons was Sophora xanthantha 1.067 g/m2.(4)The leaves of 10 plant species have certain adsorption and accumulation capacity for the six kinds of heavy metal elements,and there are certain rules,with the highest iron content,followed by zinc,manganese,cadmium,and lead,and the lowest is copper.The highest cumulative iron content is Prunus cerasifera Ehrhar f 1.277 mg/g,the highest cumulative amount of manganese is Terminalia neotaliala Capuron 0.129 mg/g,and the highest cumulative amount of zinc is 0.209 mg/g of Ceiba insignis.The highest accumulation of copper is Lagerstroemia indica L 0.059 mg/g.The highest accumulation of lead was found in the Ceiba insignis 0.017 mg/g,and the highest cumulative amount of cadmium is Erythrina crista-galli Linn 0.053 mg/g.Their seasonal trends are different.Tree species have significant differences in the accumulation of some heavy metal elements in the four seasons.Most tree species have relatively small accumulation of heavy metals in spring and high summer and autumn seasons.(5)AHP method was applied to comprehensively evaluate the tree species of 10 highway planting species in Fuzhou to select the best tree species and provide scientific data support for promoting urban forestry development and creating a good road ecological environment.The tree species with a comprehensive score of 7 or higher was Sophoraxanthantha,and the tree species with a comprehensive score of 6-7 were Ceibainsignis,Lagerstroemia indica,Bauhinia purpurea Linn,and Erythrina crista-galli Linn.The species with a comprehensive score less than 6 points were Prunus cerasifera Ehrhar f,Michelia alba DC,Cinnamomumcamphora(L.)Presl,and Terminalia neotaliala Capuron.