Research On The Function Of Ornamental Bamboos In Purifying Environment

Plants plays a very important role in improving the urban ecological environment. This study based on field surveys combined with experimental analysis, quantitative the bamboo groves green biomass of leaf area with leaf area index. And set carbon fixation and oxygen release, transpiration endothermic, absorption of environmental pollutants, soil conservation as measured evaluation indexes of the function of purifying the environment of the ornamental bamboos. Quantitative study of the purifying fuction of the ornamental bamboos through the determination of the eco-efficiency value of various bamboo species per unit leaf area plots, and on this basis to compare the various bamboo species to screen excellent bamboo species. The results are as follows:(1) Quantitative study of the bamboo grove ecological benefits based on the green biomass of leaf area and its ecological function. The ecological function decided by both the bamboo itself and the environment, the leaf area index is decided by the number of bunches, leaves and the size of the crown. The more the leaves/brunches are, the large the leaf index is. The leaf index of bamboo makes up the bamboo grove’s leaf index. In the case of the area to determine, vegetation visualization rate and leaf area index is positively correlated. The top leaf index bamboo is P. simonii f. albostriatus (102.05) and at this situation, it is the most special seed of the30species.(2) The ability of carbon fixation and oxygen release is decided by the net photosynthetic rate, the net photosynthetic rate and oxygen release is proportional relations. There are "two-peaks" of the photosynthetic curve of the bamboos, and the result shows its higher in the morning than the afternoon. The mean photosynthetic rate is between3.00-4.99μmol·m-2·s-1of all the30bamboos. Comparison of the carbon fixation and oxygen release capacity of the ornamental bamboos, the amount of absorbing CO2and releasing O2is positively correlated with its leaf area. Considering the function of releasing O2and absorbing CO2, D.farinosus(Keng et Keng f.)Chia et H.L.Fung comes the most special seed.(3)Transpiration endothermic of the bamboo is decided by the transpiration rate, and the stronger ability of transpiration, the more endothermic is. The mean max-transpiration rate is between2.00-2.99mmol·m-2·s-1of all the30bamboos. Through the comparison of the bamboos, it can be found that leaf area is positively correlated with the transpiration of water per unit area and the heat of vaporization per day. In that case, while think about the function of reducing temperature though transpiration, it comes the Pleioblastus yixingensis S. L. Chen et S. Y. Chen to be the most special seed.(4) The bamboo has a great ability of absorbing SO2, and it shows out that the highest content of sulfur is highest in autumn than other seasons. And the annual mean is4.00-7.00mg·cm-2of the four seasons, the minimum amount of absorption comes to2.79mg·cm-2. Through the sulfur content of30species of ornamental bamboo unit area and leaf area comparative analysis, the SO2absorption capacity of the bamboos is negatively correlated to its leaf area. In this situation, considering the function of absorbing SO2, Bambusa multiplex (Lour.) Raeuschel ex J. A. et J. H. Schult. var. riviereorum R.Maire is the most special seed.(5)The bamboo has a great ability of absorbing chloride, and it shows out that the content of chloride manifests as the highest in summer, and the lowest in autumn. Among all the30breed of bamboos, the amount of absorbing chloride are all larger than10.00mg·cm-2, and most between15.00-23.00mg·cm-2. Through the chloride content of30species of the ornamental bamboo unit area and leaf area comparative analysis, the chloride absorption capacity of the bamboos has nothing to do with the leaf area. While considering the function of absorbing Chloride, it comes to the Dendrocalamus sinicus Chia et J. L. Sun.(6)Analyzing the relationship between the30species of ornamental bamboo’s capacity of removing dust and the leaf area, it shows out that, the dust removal capacity is positively correlated with the leaf area. Quantitative determination of the dust on the bamboo species found that the amount of the single leaf dust is mainly concentrated between0.001-0.002g·d-1. Through the comparison of the amount of the dust absorbed by the bamboos, when considering the function of dust detention, the P. simonii f. albostriatus is the best choice of the30bamboos.