| Diumal changes of photosynthesis and light response curve of Koelreuteria bipinnata were measured
with LI-6400 in ecological function zones of Moutai winery, and the relationship between photosynthetic physiology
and ecological factors were analyzed. The results showed that the net photosynthetic rate (Pn) and light use efficiency
(LUE) of K. bipinnata had the diurnal variation of single peak, which appeared around 12:00 a.m. and 10:00 a.m.
respectively. Intercellular CO2 concentration (Ci) had opposite diurnal variation, compared with Pn. Diurnal variation of
transpiration rate(Tr) and stomatal conductance(Cond) had gradual decrease on the whole day. The relationship among
Pn, Tr, LUE, Ci, Cond and photosynthetical active radiation (PAR), air temperature (Ta), relative humidity (RH) had
characteristics of quadratic curve model. There was a significant correlation between Pn, Tr and PAR, Ta, RH. A
correlation between Cond and PAR, Ta, RH was observed. At the same time, a siginificant correlation between LUE
and PAR, Ta was also observed. PAR was the most sensitive enrironmental factor to Pn, Tr, Ci and Cond of K.
bipinnata and LUE was mainly effected by Ta. |
