摘要
沙拐枣同化枝的Ｐｎ随光照强度增加递增并具有高的ＬＳＰ。夏季的Ｐｎ、Ｐｔ和ＬＳＰ高于秋季，而ＬＣＰ、Ｒ和饱和光照下的ＣＯ２ＣＰ低于秋季。表明沙拐枣是阳地生态型植物，９月的同化枝已开始衰老。在饱和光照下，Ｐｎ随处理温度上升明显下降，相反Ｒ升高，但Ｐｔ在夏季和秋季均只有轻度变化。说明Ｐｎ下降是由Ｒ升高的致。在干旱影响下，同化枝的水势随干旱时间延长递降，Ｐｎ、Ｒ、Ｒｐ、Ｐｔ、ＬＳＰ、ＬＣＰ和Ｃｈｌ含量均呈现同样变化，饱和光照下的ＣＯ２ＣＰ则明显升高，在１２天干旱后水势下降至－１．８６ＭＰａ时，Ｐｔ仍能保持５８．５％，将干旱和高温结合处理沙拐枣柏株，结果与干旱处理相似，但受等程度加重，Ｐｔ仍能保持对照的４１．５％。这些结果表明，沙拐枣除形态结构适应外，生理功能对强光、高温和干旱的荒漠环境也有广泛的适应能力。
Net photosynthesis in assimilative shoot of C.arborescens Litv. rised gradually following with the increase on light intensity and light saturation point was higher. Net and ture photosynthesis and light saturation point were higher in summer than autumn. The results showed that C. arborescens Litv. is a sun ecotype plant and its assimilative shoot started decline in September. Net photosynthesis was significently decreased following with the gradual rising of temperature under saturation light, On the contrary,respiration tised,but changes of ture photosynthesis where little in those two seasons. These indicated that the decline of net photosynthesis was induced by the rising of respiration. there were many effects of drought on photosynthesis in assimilrtive shoot of C. arborescens Lity. Water potential declied gradually with the increase of treatment time. The change inclination of net photosynthesis, ture photosynthesis,respiration,photorespiration,light saturation point,light compensation point and chlorophyll content were similar to that of water pocential. Contrarily, Co 2 compensstion point was significently rised at saturation light,but,net photosynthesis can keep 58.5% yet after 12 days. The plant was treated by the combination of drought and temperature. The change tendency of all aspects were similar to the effects of drought. though,the degree of damage was greater,however,the ture photosynthesis is yet. kept 41.5%. It showed that except morphological constitution,physiological founction of the desert plant has wider adaptability to strong light, hight temperature and drought of environment.
出处
《林业科学》
EI
CAS
CSCD
北大核心
1997年第1期18-24,共7页
Scientia Silvae Sinicae
基金
国家自然科学基金
关键词
光合作用
呼吸作用
温度
干旱
沙拐枣
Photosynthesis Respiration,Temperature,Drought,Calligorum Arborescens Litv
