The light saturation point was lower of defoliated plants than that of non - defoliated plants . with reduced light irradiance , light saturation point also decreased 葉損失植株的光飽和點要低于未受損植株,隨光照強度的降低,植株的光飽和點逐漸下降。
Dark respiration changed with the same trend of light saturation point . but apparent quanta efficiency was not differentiated remarkably and need to be researched further 不同處理植株的暗呼吸變化趨勢同光飽和點相同,表觀量子效率卻無顯著差異,其機理還需進一步探討。
Comparing with full light treatment ( control ) , tr , gs , wue and light saturation point were significantly decreased , ci was increased by shading . so far as curve of light response , seedlings of 2 tree species represented higher photosynthetic capability under shading treatments in the ranges of low light 和對照的全光照處理相比,遮蔭處理顯著地降低了多脈青岡和金葉含笑的蒸騰速率、氣孔導度、水分利用率和光飽和點,細胞間隙co _ 2濃度在遮蔭條件下顯著上升。
The results show : ( 1 ) the light compensation point and light saturation point of s1 s2 and s3 were in range of 12 ~ 27 mol / m2 s and 180 ~ 360 mol / m2 s , respectively , and they changed with the irradiance . ( 2 ) both light compensation point and light saturation point of s1 were higher than those of s2 and 83 , and s1 showed greater capability against high irradiance than s2 and s3 . ( 3 ) the optimal temperature of the three strains were 25 , 35 and 30 , respectively , and they had temporal effect . ( 4 ) respiratory rate rose as the temperature rising , and at about 40 , it reached the peak 結果表明: ( 1 ) s _ 1 、 s _ 2 、 s _ 3的光補償點和光飽和點的變化范圍分別為12 27 mol m ~ 2 ? s和144 360 mol m ~ 2 ? s ,二者可隨光照環(huán)境的變化而變化,其中s _ 1的光補償點和光飽和點均高于s _ 2和s _ 3 ,且表現(xiàn)出強于其余兩個藻種的抵御強光輻射的能力; ( 2 )三個藻種的最適溫度分別為25 , 35 ,和30 ,具有時間效應; ( 3 )呼吸速率隨溫度的升高而升高,最大值出現(xiàn)在40附近;溫度低于25 , s _ 1的光合速率最高,呼吸速率最低,表現(xiàn)出很強的低溫適應性; ( 4 )螺旋藻的光合特性可隨光照環(huán)境的變化而變化,光強增強,可使螺旋藻的最適光照范圍增大,抵御強輻射的能力增強; ( 5 )螺旋藻受到溫度脅迫時,其最適光照范圍變窄,對光強的敏感性增加。
The light saturation points , compensation points and dark respiration rates of t . media cv . hicksii seedlings go down while the contents of chlorophyll and the ratios of chlorophyll a and b increase along with the weakening of light intensity of the growing environment , but their co2 compensation points and photorespiration rates go up 遮蔭使曼地亞紅豆杉幼苗光飽和點、光補償點及暗呼吸速率降低,但光呼吸速率和co _ 2補償點升高,葉綠素含量增大而葉綠素a b減小。