Studies On Photosynthetic And Ecological Characters Of Naidong Shancha (Camellia Japonica L.)

Many photosynthesis characters of Camellia japonica were studied in this experiment, After measured the photosynthesis parameters, Diurnal and month variety of photosynthesis factors were studied, The effects of leaf age, leaf opposition, leaf chlorophyll content, LMA, leaf direction, PAR, CO₂ concentration and temperature to Pn were studied, Deflection relational coefficient between photosynthetic factors and environment factors were analysised. The photosynthetic characters of ever-green trees in Qingdao were compared with Camellia japonica, The ecological benefit of Camellia japonica were studied also. The results as follows:1. Diurnal changes in Pn of Camellia japonica were different in different months. It presents single and double curve. When it presents double curve, the noon rest of Pn may occured. The month changes of Pn presents single curve. The transpiration rate, dark respiration and stomatal conductance are all present single curve. The water use efficiency, light use efficiency are present V curve.2. Deflection relational coefficient between leaf age, leaf opposition, leaf chlorophyll content and Pn of Camellia japonica is manifest, but the positive relativity between LMA and Pn is slim. The Pn of middle and southern leaves are higher than other directions.3. The responsive curves of photosynthesis in Camellia japonica to PAR ,CO₂ concentration and temperature can be described with quadratic equations, the parameter is high. In different months, the responsive curves are different.4. The light compensation of Camellia japonica is 31.8-42.2 umolm^-2s^-1, the light saturation is 1233.3-1375 umolm^-2s^-1, the apparent quantum requirement is 0.382-0.414. The CO₂ compensation of Camellia japonica is 33-53ppm, the CO₂ saturation is 1700-2125ppm,the carboxylation efficiency is 0.414-0.468. The best temperature of Camellia japonica is 18-20℃.5. In different time, the deflection relational coefficient between photosynthetic factors and environment factors are different. The influences of environment factors to the photosynthetic factors are different in different season.6. In July, compared to the other ever-green trees in Qingdao, the photosynthetic index of Camellia japonica is lower, From the month variety of photosynthetic index,especially in winter, the photosynthetic index of Camellia japonica is higher than the others.7. Compared to other trees, the CO₂-absorbing and O₂-releasing, temperature-decreasing and humidity-increasing of are best of all in Janunery and July, but in May and October, the Camellia japonica is lowest of all .Compared to other trees, the dust aborption ability is low.