Net photosynthesis (P n), transpiration (E), stomatal conductance (g s) and water use efficiency (WUE) of more than 218 species belonging to two different reproductive functional types, i.e. clonal (115 species) and non-clonal species (103 species), along the 1 670 km Northeast China Transect (NECT) were analyzed. The results showed that P n and WUE appeared to be lower in the east and west ends of NECT, with peaks in the middle. Transpiration was found to be higher in the west end, where most temperate desert species were distributed. On the same site, most clonal species showed higher P n and related physiological variables than non-clonal species. For different growth forms over NECT, e.g. forest trees, shrubs and grasses, meadow steppe shrubs and grasses, typical steppe shrubs and grasses, the meadow steppe and typical steppe grasses, showed higher values of physiological variables than the forest or the desert species. But for the two reproductive plant functional types (PFTs), clonal species had higher physiological variables, with averages of 22%, 15%, 23% and 14% higher than the non-clonal ones for P n, E, gs, and WUE, respectively. Such differences indicated that clonal species might have advantages over non-clonal species in utilizing environmental resources such as light, CO2, and especially water.
沿中国东北样带（NECT）分布的若干克隆植物与非克隆植物光合速率与水分利用效率的比较
蒋高明 董鸣
（中国科学院植物研究所，北京100093）
摘要：比较了沿 1 6 70km长的中国东北样带 (NECT)分布的在繁殖习性上不同的植物功能型 ,克隆植物 (clonalplant)与非克隆植物 (non_clonalplant)的光合作用、蒸腾作用、气孔导度、水分利用效率。所测定的 2 1 8种植物中有1 1 5种属于克隆植物。对于灌木和草本植物功能型而言 ,净光合速率 (Pn)和水分利用效率 (WUE)在样带东西两端较低 ,在样带中间较高 ;蒸腾速率在温带荒漠植物分布的西端出现升高的趋势。在森林乔木、森林灌木、森林草本、草甸草原灌木、草甸草原草本、典型草原灌木、典型草原草本、荒漠草原灌木、荒漠草原草本等不同功能型的植物中 ,典型草原灌木和草本植物的光合生理指标较高。在相同的生长环境中 ,克隆植物比非克隆植物表现出较高的Pn 以及其他生理指标。克隆植物的光合速率、蒸腾速率、气孔导度、水分利用效率分别比非克隆植物高出 2 2 %、1 5 %、2 3%和 1 4 %。这种现象表明克隆植物在CO2 、光能和水分资源利用能力上优于非克隆植物
关键词： 光合作用；克隆植物；非克隆植物；森林；草原；温带荒漠；中国东北样带
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