High variation in foliage and leaf litter chemistry among 45 tree species of a neotropical rainforest community
High variation in foliage and leaf litter chemistry among 45 tree species of a neotropical rainforest community
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DOI：
10.1111/j.1469-8137.2008.02438.x
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发表时间：
2008-01-01
期刊：
影响因子：
9.4
通讯作者：
Bonal, Damien
中科院分区：
文献类型：
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作者：
Haettenschwiler, Stephan;Aeschlimann, Beat;Bonal, Damien
不同生态系统水平的森林叶片碳、氮、磷（C: N: P）化学计量指标反映了植物养分利用生理策略的生态系统尺度选择。在这里，这个假设是在法属圭亚那的一个营养贫乏的低地雨林中进行的。研究了45种不同树种凋落叶和叶片中C、N、P浓度的变化，并测定了凋落叶中主要组分C的浓度。凋落物C在45.3 ~ 52.4%之间，凋落物N变化3倍（0.68 ~ 2.01%），凋落物P变化7倍（0.009 ~ 0.062%）。与叶片相比，凋落物氮、磷平均浓度分别下降30%和65%。相应的，凋落物质量N: P的变化范围由叶片的14 ~ 55转变为凋落物的26 ~ 105。吸收能力表明，在大多数物种中磷吸收最大，但与叶片相比，凋落物磷的变化显著增加。这些数据表明，受限制的生态系统水平C: N: P比率并不妨碍热带雨林树种养分利用和保护策略的高度多样化。由此产生的凋落物质量的巨大变化将影响分解者食物网内的化学计量限制，对养分动态和植物-土壤反馈具有潜在的深远影响。
Distinct ecosystem level carbon : nitrogen : phosphorus (C : N : P) stoichiometries in forest foliage have been suggested to reflect ecosystem-scale selection for physiological strategies in plant nutrient use. Here, this hypothesis was explored in a nutrient-poor lowland rainforest in French Guiana.Variation in C, N and P concentrations was evaluated in leaf litter and foliage from neighbour trees of 45 different species, and the litter concentrations of major C fractions were also measured.Litter C ranged from 45.3 to 52.4%, litter N varied threefold (0.68-2.01%), and litter P varied seven-fold (0.009-0.062%) among species. Compared with foliage, mean litter N and P concentrations decreased by 30% and 65%, respectively. Accordingly, the range in mass-based N : P shifted from 14 to 55 in foliage to 26 to 105 in litter. Resorption proficiencies indicated maximum P withdrawal in most species, but with a substantial increase in variation in litter P compared with foliage.These data suggest that constrained ecosystem-level C : N : P ratios do not preclude the evolution of highly diversified strategies of nutrient use and conservation among tropical rainforest tree species. The resulting large variation in litter quality will influence stoichiometric constraints within the decomposer food web, with potentially far-ranging consequences on nutrient dynamics and plant-soil feedbacks.