Study On The Ornamental Characteristics Of Different Ornamental Fruit Trees In Tianjin

With the gradual improvement of urban afforestation level,higher requirements are imposed on urban greening.Fruit trees are a special type of trees.They have high ornamental value and can enrich the garden landscape of the four seasons,especially for the monotonous autumn and winter season plant landscape.The fun and vitality meet the needs of building a green eco-city,with a wide range of development and application.In order to explore the fruit tree species that are suitable for the growth and ornamental effect in Tianjin,this paper uses the combination of literature review,field measurement and collection experiments to select Tianjin Water Park,Nan Cuiping Park,Changhong Park and other major parks and campuses.Fourteen different fruit trees with common adaptability and good growth were used to measure the ornamental characteristics,and their photosynthetic characteristics and fruit tolerance to low temperature were determined.AHP level analysis method was used to establish different views of Tianjin fruit trees.The comprehensive evaluation system of wood ornamental characteristics,and recommended that ornamental tree species with high comprehensive valuation of ornamental value be applied to garden landscapes,in order to provide certain reference for urban landscape greening in autumn and winter in Tianjin.The main findings are following:(1)Determination of photosynthetic characteristics.Persimmon trees,jujube trees,hawthorn,and the Midget crabapple have strong light and ability,and their growth is good.The ability of solidifying CO2 to release O2 is strong.From the standpoint of photosynthetic characteristics,it is a good landscaping tree species,while Bitter buckwheat and Torch are weak.(2)The fruit’s tolerance to low temperature.Most of the color differences did not change much.In the natural state,when the temperature gets-7℃,the fruit still has good ornamental qualities,such as Cotoneaster horizontalis,Donghong North American Begonia,torch tree,and bitter buckwheat,and the indoor freezing to-15℃ is still good for fruit ornamental effect.Silk cotton,Donghong North American Begonia,hawthorn,Cotoneaster horizontalis.Based on a comprehensive comparison,Donghong North American Begonia,bitter buckwheat,Cotoneaster horizontalis and typhoid tree are more superior to other kinds of ornamental fruit trees in tolerance to low temperatures.(3)AHP method was used to establish the evaluation system of ornamental characteristics of different fruit trees in Tianjin.It is divided into target layer(A): evaluation of ornamental characteristics of different fruit trees in Tianjin;constraint layer(C): flower(C1),leaf(C2),posture(C3),fruit(C4);standard layer(P): 22 specific trait indicators for flower diameter(P1)and flower color(P2).The weight of each standard layer(Pi)had the highest degree of low temperature tolerance(P18),followed by fruit color(P19),flower color(P2)and fruit weight(P21),and the fruit type(P13)was the smallest.(4)Comprehensive evaluation of ornamental characteristics of fruit trees and assessment of fruit ornamental characteristics.Total is divided into I,II,III,IV,and V.The total score and rank are as follows: Cotoneaster horizontalis>Amur honeysuckle> Donghong North American Begonia> Torch tree> Viburnum sargentii>Melia azedarach> Koelreuteria paniculata>Midget crabapple> Xi Yang yang North American Begonia >Hawthorn> Pomegranate> Jujubetree> Euonymus bungeanus > Persimmon tree.For the fruit ornamental characteristic C4,the fruit weight-tolerance(P18)ranks the most in the weight sorting,followed by the fruit color(P19),and the fruit type(P22)is the smallest.In terms of scores,Donghong North American Begonia = Cotoneaster horizontalis>Melia azedarach>Amur honeysuckle > Viburnum sargentii > Torch tree > hawthorn>Midget crabapple >Jujube tree> Koelreuteria paniculata > Xi Yang yang North American Begonia > Euonymus bungeanus >Pomegranate>Persimmon tree.It is recommended to select grade I and II fruit trees with high ornamental value and high scores to be widely used in gardens.