N:P stoichiometry and ontogeny of crustacean zooplankton:: A test of the growth rate hypothesis
N:P stoichiometry and ontogeny of crustacean zooplankton:: A test of the growth rate hypothesis
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DOI：
10.4319/lo.1997.42.6.1474
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发表时间：
1997-09-01
影响因子：
4.5
通讯作者：
Elser, JJ
中科院分区：
文献类型：
--
作者：
Main, TM;Dobberfuhl, DR;Elser, JJ
最近的研究假设浮游动物元素组成的差异（N:P 比率）与特定生长速率的差异有关，因为生长速率的增加需要更多的核糖体 RNA，这会导致 %P 增加和 N:P 减少。使用具有不同特定生长速率的浮游动物类群进行种间测试，并使用单个物种内的不同个体发育阶段进行种内测试。在所有五个物种中，生长速率与%N和%P呈正相关，与N:P呈负相关。然而，%N 仅从大约 8% 增加到大约 9%，而 %P 在观察到的增长率范围内变化了四倍，表明 %P 的变化推动了增长率与 N:P 之间的负相关关系。种内比较表明，水溞的生长速率与%P呈正相关，与N:P呈负相关，而大溞和大溞的生长速率与%P和N:P无关。平均 %P、%N 和 N:P 在水蚤属中存在显着差异。以及 Scapholebris mucronata 和 Bosmina longirostris 的种群。这些数据有力地支持了生长速率假说，作为浮游动物体内 N:P 差异的解释，并表明快速生长速率生命史的生物化学计量是磷密集型的。
Recent studies have hypothesized that differences in elemental composition of zooplankton (N:P ratio) are related to differences in specific growth rate, as increased growth rate requires greater ribosomal RNA, which should result in increased %P and decreased N:P. This hypothesis was tested interspecifically using zooplankton taxa with different specific growth rates and intraspecifically using different ontogenetic stages within single species. Among all five species, growth rate was positively correlated with %N and %P and negatively correlated with N:P. However, %N increased only from similar to 8% to similar to 9% while %P varied fourfold across the observed range of growth rates, indicating that changes in %P drive the negative relationship between growth rate and N:P. Intraspecific comparisons showed that growth rate was positively related to %P and negatively related to N:P for Daphnia lumholtzi, but growth rate was unrelated to %P and N:P for D. magna and D. oblusa. Mean %P, %N, and N:P differed significantly among Daphnia spp. and among populations of Scapholebris mucronata and Bosmina longirostris. These data strongly support the growth rate hypothesis as an explanation for differences in body N:P in zooplankton and indicate that the biological stoichiometry of a rapid growth rate life-history is phosphorus intensive.