不同生长时期羊草大针茅光合速率与光照强度关系的比较研究

A COMPARATIVE STUDY ON RELATION BETWEEN PHOTOSYNTHETIC RATE OF LEYMUS CHINENSIS AND STIPA GRANDIS AND LIGHT INTENSITIES OF DIFFERENT GROWING STAGES

本文对不同生长时期羊草、大针茅的光合速率与光照强度的关系进行了比较研究。在从营养生长初期到生长后期,研究结果表明:光补偿点都有增加,但羊草增加很少,大针茅增加一倍;高的饱光强出现在营养生长的高峰期、其变动幅度,大针茅大于羊草;高的净光合速率的光强系数,羊草普遍高于大针茅,并且都以营养生长高峰期最高;在10千勒光强下,相对光合速率羊草大于大针茅;羊草、大针茅的光合速率与饱和光强的变化,跟它们的叶片含水率的变化有着广泛的一致性。

This paper focuses on comparison between Leymus chinensis and Stipagrandis in relation of photosynthetic rate and light intensity from theearly stage of vegetative growth to the late growing period. The result ofhis study indicated that: 1. The increase of light compensation point was bigger in S. grandis than that in L. chinensis with the rising of light intensity. 2. High light intensity of saturation point occured at the peak period ofvegetative growth and the fluctuation of it was higher in S. grandis thanin L. chinensis. The values of high net photosynthetic rate and light intensity coeffic-ient were bigger in L. chinensis than in S. grandis and both of their highestvalues occured at the highest growth stage. 4. The relative photosynthetic rate was higher in L. chinensis than inS. grandis under 10 Klux light intensity. 5. They appeared very obvious corelations between the changes ofphotosynthetic rate and saturation light intensities of L. chinensis and S.grandis and the variation of their leaf water content.