生态环境学报2011，Vol.20Issue(1)：51-57,7.
东江中上游主要造林树种光合生理特征
The photosynthetic physiological characteristics of main tree species in the upper and middle reaches of Dongjiang watershed
摘要
Abstract
The upper and middle reaches of Dongjiang watershed is the important water source protected area of Pearl River Delta and HongKong. Situation of water resources not only impact the economic development and people's life in Pearl River Delta, but also in HongKong. Guangdong Provincial has started water conservation forest construction project in the upper and middle reaches of Dongjiang watershed so as to construct an important ecological security system of water source protected area that are expected to protect water sources and purify water quality. While the problems of afforestation design, tree species selection, cultivation and management appeared in water conservation forest construction project by field investigation. By using Li-6400 portable photosynthesis system produced by Ll-COR company, six-year-old major broad-leaved tree species for afforestation, Schima superba,Castanopsis hystrix, Michelia macclurel, and Castanopsis sfissa, in the upper and middle reaches of Dongjiang watershed for comparative studies on their photosynthetic and physiological parameter characteristics, such as photosynthesis, transpiration, and water use efficiency, as well as the diurnal changes of photosynthetic characteristics and response to light intensity of the four tree species in natural habitats. The results showed that the diurnal change of net photosynthetic rate ( Pn ) of Schima superba and Castanopsis fissa displayed a two-peak pattern, while Michelia nacclurei and Castanopsis hystrix displayed a one-peak pattern, and values of Pn of all the four trees Pn occurred at 10:00, with 8.73, 6.00, 6.68, 7.91 rmol·m-1s-1 respectively. The daily average value of Pn of Schima superba was highest, followed by Michelia macclurei, Castanopsis hystrix, and Castanopsis fissa respectively, as for the order of magnitude, the transpiration rate ( Tr ) in a descending order of Castanopsis hystrix, Schima superba, Michelia macclurei,Castanopsis fissa, and the water use efficiency ( WUE ) in a descending rank of Schima superba, Castanopsis fissa, Michelia macclurei, and Castanopsis hystrix. Schima superba thus had higher photosynthetic ability, water use efficiency, and high adaptability to the environment. The photosynthesis-light response curves of the four species could be well simulated by the non-rectangular hyperbolic models (R2 ＞ 0.98) and the exponential curves (R2 ＞ 0.98). For each of the four species, the predicted values of maximum net photosynthetic rate (P max), dark respiration (Rd) and apparent quantum yield (a) by the non-rectangular hyperbolic model were greater than those by the exponential curve respectively, and moreover were closer to the corresponding observations, while the predicted light saturation point (Lsp) by each of the two models was far lower than the observed. The young and middle-aged the four trees were photophilic and shade-tolerant with high light saturation point, low light compensation point (Lcp)and low a, and thus had high adaptability to high light and high ability to use low light and high light. These physiological studies may be helpful to planting design, tree species selection, and tending of water source forest.关键词
光合生理特征/主要造林树种/东江中上游Key words
photosynthetic physiological characteristics/ main plantation tree species/ the upper and middle reaches of Dongjiang watershed分类
农业科技引用本文复制引用
张卫强,曾令海,王明怀,殷祚云,周平,李召青,陈光胜..东江中上游主要造林树种光合生理特征[J].生态环境学报,2011,20(1):51-57,7.基金项目
广东省林业科技创新专项项目(2010KJCX013-02) （2010KJCX013-02）
国家"十一五"科技支撑计划专题项目(2006BAD03A1805) （2006BAD03A1805）
国家林业公益性行业科研专项项目(200904015) （200904015）
广东省科技计划项目(2009B020303006) （2009B020303006）
