夏季自然高温对桉树光合速率和暗呼吸速率的影响

Photosynthesis Properties of Seven Eucalyptus spp. at Summer Natural High Temperature

在湖南夏季的自然高温下 ,所测 7种桉树的日平均净光合速率在 12 56～ 2 7 85mg·dm- 2 ·h- 1之间 ,日平均暗呼吸速率在 6 0 6～ 2 2 39mg·dm- 2 ·h- 1之间。高温对桉树净光合速率的影响依品种而异。樟脑桉和蓝桉的净光合速率最高峰值出现在 35℃的气温下 ,而邓恩桉的净光合速率却受 35℃气温的显著抑制。桉树暗呼吸速率并不随气温的升高而增大。

The photosynthetic properties of several\% Eucalyptus\% spp were measured at summer high temperature in Hunan Province. The results showed that the daily average net photosynthetic rates of these several\% Eucalyptus\% spp varied between 12 56～27 85 mg·dm\+\{-2\}·h\+\{-1\}, daily average dark respiration varied between 6 06～22 39 mg·dm\+\{-2\}·h\+\{-1\}. The effect of high temperature on the net photosynthetic rates varied with changing of variety of \%Eucalyptus\% sp ,\%Eucalyptus\% spp , \%E maidenii\% and\% E camphora\% get their highest net photosynthetic rates at 35 ℃, while the photosynthesis of\% E dunnii\% is remarkable restrained at 35 ℃ Dark respiration ratio of\% E \% spp does not change with the rising of temperature.