安吉毛竹林净生态系统碳交换量及叶绿素荧光参数的变化  

Variations of net ecosystem carbon exchange and chlorophyll fluorescence parameters of Phyllostachys edulis forest in Anji

作　　者：龚莎莎[1] 江洪[1,2] 马锦丽[1] 舒海燕[3] 陈晓峰[1] 

机构地区：[1]浙江农林大学国际生态研究中心,浙江杭州311300 [2]南京大学国际地球系统科学研究所,江苏南京210093 [3]西南大学生命科学学院,重庆400715

出　　处：《浙江农业学报》2016年第6期1003-1008,共6页Acta Agriculturae Zhejiangensis

基　　金：国家自然科学基金项目(61190114;41171324);上海市科学委员会项目(12231205101);科技部国家科技基础条件平台项目(2005DKA32300)

摘　　要：利用涡度相关法,对安吉毛竹林生态系统的碳通量进行实时观测,同时用叶绿素荧光仪PAM-2500测定通量框架下毛竹的叶绿素荧光参数。分析了毛竹林净生态系统碳交换量(NEE)的日变化和月平均变化及荧光参数变化。结果表明,NEE值在6:00—7:00开始转为负值,至17:00—18:00转为正值;白天表现为碳汇,并且在数值上,NEE值的负值最高点表现为秋季(9月,10月,11月)>春季(3月,4月,5月)>冬季(12月,1月,2月),说明毛竹CO2通量具有明显的季节变化。逐月NEE值变化范围为-25.563 3~85.531 2 g C·m^(-2)·月-1,12和1月份NEE值较低,1月份达到最低点。叶绿素荧光参数中PSⅡ的最大光合量子产量(F_v/F_m)先降后升,12月,1月和3月份F_v/F_m低于正常水平,与其他月份差异显著(P<0.05),说明毛竹在这3个月份受到了胁迫,光化学效率降低;F_v/F_o与F_v/F_m趋势相同,12月,1月和3月份潜在活性最低,并且与其他月份差异显著(P<0.05);PSⅡ的实际光合量子产量(ФPSⅡ)变化趋势与F_v/F_m、光化学猝灭系数(q P)大致相同;在10月至翌年3月份,q P逐渐下降之后开始升高,同时伴随非光化学猝灭系数(q N)值的上升和下降。研究表明,毛竹在受到低温胁迫时,会导致其吸收的光能用于光化学电子传递的部分减少,光合碳同化率下降。CO2 fluxes of Phyllostachys edulis ecosystem in Anji was 24 hours observationed using an eddy covariance method. Meanwhile, the chlorophyll fluorescence parameters of Phyllostachys edulis under the framework of CO2 flu-xes were measured by PAM-2500 chlorophyll fluorometer. The diurnal variations and monthly variation of net ecosys-tem carbon exchange （ NEE） and the variations of chlorophyll fluorescence parameters were analyzed. The results showed that the monthly NEE was always negative in 6：00—7：00, positive in 17：00—18：00, indicating that Phyl-lostachys edulis assimilated CO2 in daytime. The highest NEE in the numerical value was autumn （ September, Octo-ber, November） 〉 spring （March, April, May） 〉 winter （December, January, February）, which showed that the NEE had obvious seasonal characteristics. The monthly variation range of NEE value was-25. 5633-85. 5312 gC·m^-2·month^-1 , with the minimum in January. The maximal photochemical efficiency of photosystemⅡ（ Fv/Fm ） showed the trend of down after rise, the values from December to March were significantly lower than those of the normal levels （P〈0. 05）. It illustrated that Phyllostachys edulis was stressed and photochemical efficiency（ФPSⅡ） was decreased in that three months. Fv/Fo was the same as Fv/Fm. Photochemical quenching coefficient （qP） gradu-ally decreased from October to March then rose. On the contrary, non-photochemical quenching coefficient （ qN） grad-ually rose then decreased. The study showed that low temperature stress reduced the proportion of light energy which used for photochemical electron transport, and decreased the photosynthetic carbon assimilation of Phyllostachys edulis.

关 键 词：毛竹林 生态系统 净生态系统碳交换量 叶绿素荧光 

分 类 号：S795.7[农业科学—林木遗传育种] S718.5[农业科学—林学]