Study On Canopy Structure,Dust Catching Ability And Sterilization Of Jacaranda Mimosifolia

This study used dry cleaning method, improved natural sedimentation method and field survey, analysis of different specifications Jacaranda mimosifolia in Chengdu, Zigong, Suining, Jiajiang, Renshou, etc by botanical way. Focusing on the bacterial culturing and observing about Jacaranda mimosifolia, Cinnamomum pedunculatum, Loropetalum chinense, Ficus altissima., Broussonetia papyrifera at Chengdu riyue avenue. Discussion on the characteristics of canopy structure about Jacaranda mimosifolia,as well as its dust catching ability and bactericidal capacity situation. The following results were obtained through the experimental study:The experiment obtained through investigation and survey methods of Botany branching characteristics of Jacaranda mimosifolia and canopy structure characteristics,the branch high of adult Jacaranda mimosifolia is in the range of 1.90-3.00m, generally 4 to 5 branches,2 to 4 branches each level. Wherein there are average 2.9 branches on the first branching point. Adult Jacaranda mimosifolia leaves mainly in the 3 to 5 branches, the top of each twig grows 16 to 20 pinnates,10 to 24 leaflets on each pinnate, in which area is between 0.025 to 0.029 m2There are obvious positive correlation among tree height and DBH(r=0.7468, P< 0.01),crown diameter(r=0.8211,p<0.01),leaf number(r=0.7637, P<0.01),leaf area(r= 0.7637,P<0.01),LAI(r=0.6155,P<0.05),height of crown(r=0.8490,P<0.01)about Jacaranda mimosifolia. As can be seen from therelationship between tree height and DBH of Jacaranda mimosifolia, under certain conditions, the higher thetree, the greater the DBH. Besides,DBH and leaf number (r=0.9086,P<0.01)showed extremely significant positive correlation,so under certain conditions,the higher the Jacaranda mimosifolia, the greater the canopy and leaf area,the ability of dust catching,bactericidal,reduced noise and ecological functions will bestronger.Second, the relationship between dust catching ability and canopy of Jacaranda mimosifoliaAccording to Chengdu, Zigong, Suining in winter and spring with the same habitat beside the road of Jacaranda mimosifolia, Cinnamomum pedunculatum, Loropetalum chinense, Ficus altissima., Broussonetia papyrifera,and research of dust catching, come to the conclusion that the average amount of dust absorption about different species: L.chinense>F. altissima>B. papyr ifera>J.mimosifolia>C. pedunculatum, this phenomenon may have a great relationship with the plant surface structure of the blade. Such as microvilli make the blade of Jacaranda mimosifolia more dust,but since each pinnae composed of many leaflets,which are more susceptible to wind speed and other external influences,and dust on the blades scatter easily. Combined with leaf area increasing, dust catching ability increased, with leaflets area of Jacaranda mimosifolia is small, thus weakened the dust catching ability of Jacaranda mimosifolia. But from the point of view of Jacaranda mimosifolia canopy structure, the dust catching depends mainly on leaves, if the richer Jacaranda mimosifolia canopy structure, the more its branches and grading, and Jacaranda mimosifolia leaves mainly from the level 3 began to distribution and surrounded at the top, so the more branch and grading is, the greater the amount of leaf, and leaf area is bigger, dust catching ability also increases. Therefore, dust catching ability was positively related to canopy structure of Jacaranda mimosifolia. Third, the relations between bactericidal and canopy of Jacaranda mimosifolia.Through collecting leaves of Jacaranda mimosifolia, Cinnamomum pedunculatum, Loropetalum chinense, Ficus altissima, Broussonetia papyrifera on the Chengdu Riyue Avenue, then set up different concentration of culture medium, different temperature condition(10℃,20℃,25℃,30℃,37℃) and different time (24h,48h,72h),and recording experimental data of training, it is concluded that area about the experiment of five kinds of plant leaves culture bacteria:B.papyrifera> L.chinense>F. altissima>C. pedunculatum> J.mimosifolia. Combined with the average amount of dust absorption about different species:L.chinense>F altissima>B. papyrifera>J.mimosifolia>C. pedunculatum,and calculate that units colony area of different bacterial culture media that in experiment of different species C. pedunculatum> B. papyrifera> L. chinense>F. altissima> J.mimosifolia. Due to the the main microorganisms in air attached to the dust, and plants have strong dust catching ability, the same amount of dust and cultivate bacteria area smaller, indicating that plants bactericidal ability is stronger. Therefore, the results of 5 different kinds of plants in the experiment were compared:J.mimosifolia> F. altissima> L.chinense> B. papyrifera> C. pedunculatum.Due to some leaves secrete allelochemicals, Jacaranda mimosifolia has ability of antibacterial and air sterilization. While the canopy structure of Jacaranda mimosifolia richer, more leaves, the allelochemicals increased, so the stronger bactericidal effect. Therefore, there is a strong positive correlation between canopy structure and bactericidal ability of Jacaranda mimosifolia. Fourth, the relationship between dust catching ability and bactericidal of Jacaranda mimosifoliaStudy shows, mainly in the air microorganisms attached to dust.Due to the the main microorganisms in air attached to the dust, and Jacaranda mimosifolia have strong dust catching ability, while performance in the secretion of allelochemicals, can kill microorganisms on the part of the dust, with a strong bactericidal capacity, purify the air, beautify the environment.In conclusion, because of its unique botanical canopy structure of Jacaranda mimosifolia, there are distinctive features on the dust catching abiliy and killing microorganisms. This study can provide theoretical basis from an objective reference for the future city and green space system construction.