坡度对紫花苜蓿和狗牙根光合生理特性的影响  

Effect of Slope Gradient on Physiological Characteristic of Mediccago sativa and Cynodon dactylon

作　　者：祝顺波[1] 许文年[2] 刘刚[2] 赵娟[1] 陈燚格[1] 

机构地区：[1]三峡大学化学与生命科学学院,湖北宜昌443002 [2]三峡库区生态环境教育部工程研究中心(三峡大学),湖北宜昌443002

出　　处：《水土保持研究》2012年第2期218-221,共4页Research of Soil and Water Conservation

基　　金：国家自然科学基金项目(50879043);国家水体污染控制与治理科技重大专项课题(2008ZX07104-003-03)

摘　　要：通过模拟试验,测定不同坡度条件下紫花苜蓿和狗牙根光合和蒸腾速率变化,从而分析坡度对护坡植物光合生理特性的影响。结果表明:紫花苜蓿和狗牙根的净光合速率与蒸腾速率随着坡度的增大表现为"单峰"型,且都在坡度为15°左右达到最大值。随着坡度的增大,两种植物的光合生理都受到胁迫影响,但紫花苜蓿变化极显著,而狗牙根则表现为在坡度60°以下的变化很小。紫花苜蓿的固氮能力较强,能在30°以下坡面较好地生长;而狗牙根的强抗逆性,可以在高陡边坡绿化中担当重要角色。研究不仅为边坡修复的物种选择提供了科学参考,也为边坡生态修复提供了理论依据。To analyze the influence of slope gradient on photosynthetic physiological characteristics of vegetation,the change rate of photosynthetic and transpiration of Medicago sativa and Cynodon dactylon growing on slopes with different gradient were measured.The results showed that the photosynthetic rate and transpiration rate of Medicago sativa and Cynodon dactylon were increasing with slope gradient,and the maximum occurred on 15° slope.The photosynthetic physiological characteristics of these two plants were affected by slope gradient.The changes of Medicago sativa was significant,but Cynodon dactylon changed little when the gradient is less than 60°.Medicago sativa grows well on slope below 30° due to its good nitrogen-fixing ability.Nevertheless,Cynodon dactylon could grow on steep slope in greening engineering.This study provided not only scientific references for species selection,but also theoretical basis for ecological restoration on slope land.

关 键 词：紫花苜蓿 狗牙根 坡度胁迫 光合速率 蒸腾速率 光合色素 

分 类 号：Q945.78[生物学—植物学] S541.1[农业科学—作物学]