巨尾桉光合特征与水分消耗的季节适应  

Seasonal Variations in Photosynthesis and Water Use Efficiency of Eucalyptus grandis × E. urophylla

作　　者：邓云[1,2] 张磊[2,3] 王冰[2] 苏文华[2] 张光飞[2] 邓晓保[1] 

机构地区：[1]中国科学院西双版纳热带植物园,勐腊666303 [2]云南大学生态学与地植物学研究所,昆明650091 [3]云南新兴职业学院,昆明650501

出　　处：《林业科学》2010年第8期84-90,共7页Scientia Silvae Sinicae

基　　金：云南省政府科技专项项目"云南人工桉树林的生态环境效应及调控对策研究"

摘　　要：使用Li-6400于旱季和雨季分别对云南省澜沧地区种植巨尾桉的净光合速率和蒸腾速率、气孔导度进行测定。研究发现:雨季巨尾桉光饱和点达1590μmol photon·m-2s-1,而旱季土壤水分不足时光饱和点仅867μmol photon·m-2s-1,光补偿点亦有下降。旱季气孔导度对蒸腾和光合的限制作用明显强于雨季。旱季巨尾桉气孔限制强度及蒸腾对光强变化的响应均与本地植物红木荷类似,而雨季巨尾桉的净光合速率远高于后者。巨尾桉具有与环境水分供应变化相协调的水分利用策略,旱季减少水分消耗以尽量节水,雨季则充分光合以获得更多生长。其类似本地植物季节变化的蒸腾特征和水分利用对策有利于维持群落地段的水分平衡。The photosynthesis,transpiration and stomatal conductance of Eucalyptus grandis × E. urophylla was studied under different seasons in Lancang,Yunnan Province with Li-6400. Result showed that LSP of E. grandis × E. urophylla was 1 590 μmol photon·m -2 s -1 in rainfall season,and decreased to 867 μmol photon·m -2 s -1 in dry season. Seasonal drought enhanced stomatal limitation to both photosynthesis and transpiration. E. grandis × E. urophylla had similar change patterns of stomatal conductance and transpiration in response to irradiation intensity as native species Schima wallichii in dry season,but the photosynthesis was much higher than Schima wallichii. E. grandis × E. urophylla could adapt different water conditions in different seasons as native species.

关 键 词：巨尾桉 光合速率 蒸腾特征 水分利用效率 

分 类 号：S718.43[农业科学—林学]