Analysis Of Terrestrial Plant Species Diversity And Its Ecological Effects In Hefei City Park

Urban park is an important carrier for urban greening and beautifying and improving ecological environment,while plant community is the basic component unit of urban park.The rationality and scientific nature of plant community structure directly affect the exertion of ecological effect of urban park.Hefei has been committed to the establishment of a national ecological garden city,so it is of great practical significance to study the plant community in Hefei.The diversity of garden plants in four urban parks,including Baohe Park,Yinhe Park,Xinghua Park and Gu Xiaoyaojin,was analyzed.temperature and humidity,dust retention,noise reduction rate and other indicators.The main conclusions are as follows:Plant community composition:(1)There are 152 species of garden plants of 70 families and 140 genera in hefei survey park,including 55 species of trees,37 species of shrubs,67 species of herbs and only 7 species of lianas.There are 118 species of dicotyledons belonging to 108 genera in 56 families.There are 25 species of monocotyledons belonging to 9 families and 24 genera.Gymnosperms 8 species(4 families,7 genera),ferns 1 species(1 family,1 genus).Rosaceae,gramineae,compositae are widely used in hefei parks.Important value analysis of plant community,tree layer of dominant species of Trachycarpus fortunei,Cinnamomum camphora,Ligustrum lucidum,Osmanthus fragrans,etc.,the shrub layer of dominant species for Mahonia fortunei,Rhododendron pulchrum,Ophiopogon bodinieri(2)The geographical distribution types of genera are divided into 14 distribution types.The distribution characteristics are plants are mainly distributed in the temperate zone,and the temperate zone distribution is 77 genera,accounting for 55% of the total genera.There are 43 genera in tropical distribution,accounting for 30.71% of the total genera 16 genera in the world 11.43% of the total genera 4 genera endemic to China 2.86% of the total genera.(3)Survey statistics show that there are a total of 22 families,39 genera and 40 species of exotic plants in the surveyed parks.Among them,there are 25 kinds of herbs,8 kinds of trees,7 kinds of irrigation,and there are no foreign plants in lianas.There were 27 species of invasive plants in 13 families,26 genera and 27 genera,among which the most invasive plants were in the Compositae family(7 species),followed by the Gramineae family(5 species),followed by the Fabaceae family,Amaryllidaceae,Amaranthaceae,Apocynaceae,and so on.According to its source,17 species of 17 genera and 12 families were invasive plants,most of which were introduced intentionally,17 species of 17 genera and 12 families and 10 genera and 10 species of 10 genera and 10 species of 5 families were introduced unintentionally.According to the analysis of origin,it is mainly America(18 species),followed by Europe(6 species)and Asia(3 species).2.Plant community structure:According to plant life-form statistical analysis,among80 plant community,hefei park tree layer species in plant communities is still in the period in young adults,halosols deserts structure of plant communities have 50,accounting for62.5% of the total population,Joe grass structure of plant communities have 30,accounting for 37.5% of the total population,halosols deserts stratified structure is the main structure types in hefei park plant community;The plant species analogy of trees and grass is about1:0.67:1.22.The ratio of evergreen to deciduous in the tree layer was about 1:1.75,and that of evergreen to deciduous in the shrub layer was about 1:0.68.3.Diversity analysis was carried out according to the number of species in each layer of trees,shrubs and grass,and the species richness of hefei park was shown as herb layer(57.45)>Tree layer(38.12)>In the shrub layer(20.30),the Simpson diversity index showed as the tree layer(0.97)>Shrub layer(0.91)>Herbaceous laye(0.89);shannon-winner diversity index was specifically expressed as tree layer(1.76)>Herb layer(1.37)>In the shrub layer(1.35),the Pielou evenness index showed as the tree layer(0.37)>Shrub layer(0.33)>Herb layer(0.29).4.Ecological effects of plant communities:(1)The changes of environmental temperature and humidity are obviously different with different plant configurations.The effect of cooling and humidifying was shown in turn as arborescence >Joe grass & gt;The lawn& gt;Plant morphological characteristics such as bare land,plant species,composition,crown width,tree height and chest diameter had obvious effects on plant cooling and humidification.(2)Within different distances from the sound source,the plant community has a weakening effect on the noise.The plant community has a good noise reduction rate at 10 m,and the noise reduction rate of the plant community increases with the increase of the distance.Different plant communities have different noise reduction ability due to their species composition and morphological structure.(3)According to the size of dust retention per unit area,30 kinds of greening plants were divided into three categories,and the amount of dust retention such as Osmanthus fragrans,Platycladus orientalis,Pittosporum tobira and Loropetalum chinense were between 1.8750±0.0059-2.6292±0.0673 g/m2,which was the first category.Fatsia japonixa,jasminum nudiflorum,Cinnamomum camphora,Euonymus alatus,Magnolia grandiflora,Ophiopogon japonicus,Aucuba japonica,Ligustrum lucidum,Viburnum odoratissimum,Robinia pseudoacacia,Broussonetia papyifera,Koelreuteria paniculata,Nerium oleander,Buxus sinica,Prunus cerasifera,Photinia serratifolia,Triadica sebifera,Prunus cerasifera,Dust retention ranges from 0.7615±0.0109-1.5077±0.0172 g/m2,the second category;Prunus yedoensis,Pyracantha fortuneana,Cercis chinensis,Hypericum monogynum,Ginkgo biloba,Elaeocarpus decipiens,Punica granatum,Metasequoia glyptostroboides and other dust in0.1783±0.0026-0.5715±0.0061 g/m2,the third category.