Domingues Tomas Ferreira, Ishida F Yoko, Feldpausch Ted R, Grace John, Meir Patrick, Saiz Gustavo, Sene Olivier, Schrodt Franziska, Sonké Bonaventure, Taedoumg Herman, Veenendaal Elmar M, Lewis Simon, Lloyd Jon
School of GeoSciences, University of Edinburgh, Edinburgh, UK.
Oecologia. 2015 Jul;178(3):659-72. doi: 10.1007/s00442-015-3250-5. Epub 2015 Mar 10.
Photosynthesis/nutrient relationships of proximally growing forest and savanna trees were determined in an ecotonal region of Cameroon (Africa). Although area-based foliar N concentrations were typically lower for savanna trees, there was no difference in photosynthetic rates between the two vegetation formation types. Opposite to N, area-based P concentrations were-on average-slightly lower for forest trees; a dependency of photosynthetic characteristics on foliar P was only evident for savanna trees. Thus savanna trees use N more efficiently than their forest counterparts, but only in the presence of relatively high foliar P. Along with some other recent studies, these results suggest that both N and P are important modulators of woody tropical plant photosynthetic capacities, influencing photosynthetic metabolism in different ways that are also biome specific. Attempts to find simple unifying equations to describe woody tropical vegetation photosynthesis-nutrient relationships are likely to meet with failure, with ecophysiological distinctions between forest and savanna requiring acknowledgement.
在喀麦隆（非洲）的一个生态交错区，对近缘生长的森林和稀树草原树木的光合作用/养分关系进行了测定。尽管稀树草原树木基于面积的叶片氮浓度通常较低，但两种植被类型的光合速率并无差异。与氮相反，森林树木基于面积的磷浓度平均略低；光合特性对叶片磷的依赖性仅在稀树草原树木中明显。因此，稀树草原树木比其森林同类更有效地利用氮，但仅在叶片磷含量相对较高的情况下。与其他一些近期研究一起，这些结果表明氮和磷都是木本热带植物光合能力的重要调节因子，以不同方式影响光合代谢，且这些方式也具有生物群落特异性。试图找到简单统一的方程来描述木本热带植被光合作用-养分关系很可能会失败，需要认识到森林和稀树草原之间的生态生理差异。
