The Analysis And Comparison Of Photosynthetic Characteristics And Ecological Benefits Among Four Ornamental Plants

In order to deploy the plants in urban green space scientifically and reasonably and full play their ecological benefits,the photosynthetic characteristics,solar energy utilization ability,carbon sequestration and oxygen release capability,humidification cooling capacity,antibacterial activity and dust catching of Aster tataricus,Campanula rotundifolia,Hylotelephium erythrostictum and Echinacea purpurea were studied from May to August.The results showed that:Firstly,Diurnal change of 4 kinds of ornamental plants photosynthetic rate showed single peak and double peak.Aster tataricus in May,Campanula rotundifolia in May and August,Hylotelephium erythrostictum in May,Echinacea purpurea in May and June showed single peak curve,Aster tataricus in 6~8 months,Campanula rotundifolia in 6~7 months,Hylotelephium erythrostictum in 6~8months,Echinacea purpurea in 7~8 months showed double peak curve.The order of photosynthetic rate from 5~8 months was as follows: Aster tataricus > Campanula rotundifolia > Echinacea purpureas > Hylotelephium erythrostictums.Secondly,correlations existed among the net photosynthetic rate and leaf temperature,photosynthetically active radiation of 4 kinds of ornamental plants.Extremely significant relativity existed between net photosynthetic rate and photosynthetically active radiation of Aster tataricus and Echinacea purpureas.Significant relativity existed between Aster tataricus’ net photosynthetic rate and leaf temperature.Very significant positive correlation existed between net photosynthetic rate and stomatal conductance of Aster tataricus,Hylotelephium erythrostictum and Echinacea purpurea.Intercellular CO2 concentration had less effect on 4 kinds of ornamental plants’ net photosynthetic rate.Thirdly,the order of solar energy utilization of 4 kinds of ornamental plants from May to June was Aster tataricus > Echinacea purpurea > Campanula rotundifolia > Hylotelephium erythrostictum.In July and August,the order of solar energy utilization was Aster tataricus > Campanula rotundifolia > Echinacea purpurea > Hylotelephium erythrostictum.The solar energy utilization of 4 kinds of ornamental plants was higher in the condition of low light than in bright light.Among four kinds of plants,Aster tataricus exhibited the strongest carbon sequestration and oxygen release capability,followed by Echinacea purpurea and Campanula rotundifolia,Hylotelephium erythrostictums had the minimum ability.Campanula rotundifolias exhibited the strongest humidification cooling capacity,followed by Aster tataricus,Echinacea purpurea and Hylotelephium erythrostictum.The order of 4 kinds of ornamental plants dust detention ability from high to low was: Campanula rotundifolia,Hylotelephium erythrostictum,Echinacea purpurea and Aster tataricus.The order of 4 plants antibacteria capability was Hylotelephium erythrostictum > Aster tataricus > Campanula rotundifolia > Echinacea purpurea.Considering the eco-efficiency indexes,the order of 4 kinds of ornamental plants ecological benefit was as follows: Aster tataricus > Campanula rotundifolia > Echinacea purpurea > Hylotelephium erythrostictum.