天山北坡不同区域野生鸭茅种群光合生理生态特性研究

Study on Photosynthetically and Ecophysiological Characteristics of Dactylis glomeratain Different Regions on the Northern Slope of Tianshan Mountain

野生鸭茅（Dactylis glomerata）属多年生优良禾本科牧草,通过对分布于天山北坡不同野生鸭茅光合生理生态特性的比较,分析其在不同生长区域的生态适应性.结果表明,不同区域野生鸭茅种群的净光合速率日变化曲线均呈先降低再升高再降低趋势,11：00-12：00达到一个峰值,随之下降.光合有效辐射、蒸腾速率、气孔导度、大气温度及叶片温度测定中所有曲线日变化的峰值位置均在12：00-15：00,随后出现下降趋势.不同区域野生鸭茅种群的光能利用效率日变化动态曲线均呈现倒“V”型,在15：00左右出现低谷;水分利用效率日变换曲线整体上呈现出高G低G高G低的走势.分析表明,不同区域野生鸭茅种群对环境的适应产生了光合生理机制的差异.

Dactylis glomerata was a kind of excellent perennial grass forages.The results of diurnal dynamic changes indicated that the diurnal variation curve of the three regions of D.glomerata decreased first and then increased and then decreased,and reached to peak at 11:00-12:00am and then decreased.The results of photosynthetically active radiation intensity,transpiration rate,stomatal conductance,leaf temperature and air temperature measurement showed that the peak position of the diurnal variation of all the curves was at12:00-15:00,then followed downward trend.The light use efficiency diurnal variation curves of the three regions showed an inverted'V'type,appeared trough at around 15:00noon.while,the whole day transformation curve of water use efficiency showed a high-low-high-low trend,the light use efficiency and water use efficiency of D.glomerataat three regions was different.