不同坡位胡枝子光合特性及其影响因子研究  

Study on Photosynthetic Characteristics and Its Influencing Factors of Lespedeza bicolor Turcz. under Different Slope Situation

作　　者：赵思金[1] 韩烈保[1] 张咏新[2] 张才厚 肖昆仑[1] 

机构地区：[1]北京林业大学,北京100083 [2]辽宁农业职业技术学院,辽宁营口115009 [3]抚顺矿业集团责任有限公司林业处,辽宁抚顺113004

出　　处：《西北植物学报》2008年第2期342-347,共6页Acta Botanica Boreali-Occidentalia Sinica

基　　金：北京市门头沟区政府基金项目(D0605046040191)

摘　　要：采用Li-6400光合分析仪,在自然条件下对不同坡位胡枝子叶片净光合速率(Pn)、蒸腾速率(Tr)及其相关环境因子的日进程进行了观测。结果表明:在5月份晴天条件下,不同坡位胡枝子叶片Pn、Tr日变化均呈单峰曲线,而水分利用效率(WUE)表现出早晚高、中午低的变化趋势。它们的叶片Pn峰值不同坡位均出现在11:00,而且上坡位峰值和日平均值略高于下坡位和平地(P>0.05);Tr峰值上坡位出现在11:00,下坡位和平地均出现在13:00,且上坡位峰值和日平均值显著低于下坡位和平地(P<0.01);上坡和平地WUE均在15:00达到最大值,但下坡位推迟到17:00,而且上坡位峰值和日平均值略高于下坡和平地(P>0.05)。胡枝子叶片Pn与PAR、Ca、RH等生态因子间的拟合方程分别为:Y上pn=-26.148+0.002 3xPAR+0.11xCa-0.84xRH,Y平pn=-19.148+0.001 9xPAR+0.106xCa+0.86xRH,Y下pn=-27.148+0.002xPAR-1.16xRH,其主要生态影响因子及其大小顺序为XPAR>XRH>XCa。研究发现,不同坡位胡枝子叶片主要光合指标日变化趋势相似,但其峰值出现时间和高低有别,其主要生态影响因子为光合有效辐射、大气相对湿度和大气二氧化碳浓度。Diurnal variations of Pn or Tr of Lespedeza bicolor Turcz.under different slope situation were studied under natural conditions by Li-6400 photosynthesis analyzer.The results indicated that the curve of diurnal variation of Pn,Tr were both one-peak curve on the may sunny day.The diurnal variation of WUE was high in morning and evening and low in midday.The peak value of Pn occurred at 11：00 O＇clock and that top slope situation is slightly higher than foot slope situation and flat（P〉0.05）;The Tr peak value of top slope situation occurred at 11：00 O＇clock,The peak value of lower slope situation and flat occurred at 13：00 O＇clock,moreover Tr diurnal average value and peak value of top were remarkable lower than other those（P〈0.01）;WUE diurnal average value and peak value of top slope situation were slightly higher than those under foot slope situation and flat（P〉0.05）.The related equation was constructed in this paper,Y上Pn=-26.148＋0.002 3xPAR＋0.11xCa-0.84xRH,Y平Pn=-19.148＋0.001 9xPAR＋0.106xCa＋0.86xRH,Y下Pn=-27.148＋0.002xPAR-1.16xRH.The order of influencing factors on Pn was XPAR〉XRH〉XCa.

关 键 词：胡枝子 坡位 光合速率 蒸腾速率 水分利用效率 

分 类 号：Q948.1[生物学—植物学]