The Photosynthetic Characteristics And Simulation Of Coniferous And Broad-leaved Trees In Daqing Mountain

In this paper, the light response curve and the diurnal course in the photosynthetic rate of7coniferous and broad-leaved tree species such as Pinus tabulaeformis,Betula platyphylla Suk, Quercus liaotungensis,Populus davidiana,Prunus armeniaca,Ostryopsis davidianary and Spiraea salicifolia messured and studied in natural condition in Daqing Mountain using LI-6400portable photosynthesis system,AP-4Dynamic stomatal system and NK5925meteorological.Furter, the photosynthetic rste,stomatal conductance and transpiration rate model of the tested trees established on leaf level.The results show that:(1)The net photosynthetic rate of the tested tree increases rapidly in low light and slowly in high light as the light intensity increases and the relationship between photosynthetic rate and light intensity can simulated as the non-rectangular hyperbola model in different months on the growth season of tree(relational coefficient≥0.9).(2)The light quantum efficiency,maximum net photosynthetic rate,light saturation point,light compensation point and dark respiration rate are different with the different tree speseis.the light compensation point of S.salicifolia and O.davidianary is lest and that of P. tabulaeformis is most in tested trees,and that order of other trees is B. platyphylla,P. davidiana, Quercus liaotungensis and P. armeniaca from less to greater on the average of the light compensation point in7and8month.The order result showes the light compensation point can be used to evaluate tree adaption to light.(3) In the sunny condition, the diurnal variation curve of the photosynthetic rate of P. tabulaeformis and S. salicifolia showed double peak type curve,others test tree showed single peak. The photosynthetic rate of Q. liaotungensis,B. platyphylla Suk,P. armeniaca,O. davidianary P. davidiana have high peak value. S. salicifolia and P. tabulaeformis have low peak value. the photosynthetic rate of the test tree have the peak value in June and have the minimum value in September.(4) The photosynthetic rete,stomatal conductance and transpiration model for leaf were constructed by the photosynthetic curve model responsed to light. The test results between simulation and measure in photosynthetic rate,stomatal conductance and transpiration show the relativity coefficient between simulation and measure value reaches0.99in those light course for7species trees.In those diurnal course the relative error between simulation and measure is11%-22%for the net photosynthetic rate,6%-33%for stomatal conductance,14%-29%for transpiration rate,and X2test is no significant difference (p<0.05).The research show that the models can simulate photosynthetic rate,stomatal conductance and transpiration rate for leaf.