Leaf NPK stoichiometry, δ15N , and apparent nutrient limitation of co‐occurring carnivorous and noncarnivorous plants
Leaf NPK stoichiometry, δ15N , and apparent nutrient limitation of co‐occurring carnivorous and noncarnivorous plants
复制标题
食虫和非食虫植物的叶 NPK 化学计量、δ15N 和表观养分限制
DOI：
10.1002/ecy.3825
复制
发表时间：
2022
期刊：
影响因子：
4.8
通讯作者：
Shiba, Zackary W.
中科院分区：
文献类型：
--
作者：
Givnish, Thomas J.;Shiba, Zackary W.
之前的荟萃分析表明，食肉植物——尽管从猎物中获取氮、磷和钾——这些营养物质的叶子浓度明显低于非食肉植物。然而，这些研究主要将营养贫乏的栖息地的食肉动物与营养丰富的地点的非食肉动物进行比较，因此报告的差异可能反映了栖息地的差异以及营养捕获策略的差异。在这里，我们检查了同一营养贫乏沼泽中的 3 种肉食性植物和 12 种非肉食性植物，比较它们的叶面营养浓度，使用叶子 NPK 化学计量评估它们的营养限制模式，并使用稳定 N 同位素混合模型估计食肉动物从猎物中获取的 N 百分比。我们假设（1）在同样营养贫乏的栖息地，食肉动物叶子的营养浓度接近或超过非食肉动物； (2) 不同功能群的物种表现出不同的化学计量模式和明显的营养限制； (3) 非食肉动物可能有证据表明他们使用其他获取或保存营养的方式来减少营养限制。在威斯康星州北部的 Fallison Bog，食肉植物（圆叶茅膏菜、紫瓶子草、大狸藻）的叶百分比 C 和 N:P 比率显着较低，δ15N 较高，并且在叶 N、P、K 和 δ13C 方面与非食肉植物没有差异。与仅限于泥炭藓的非莎草相比，莎草具有显着较低的叶百分比 P、百分比 C 和 N:K 比率，以及较高的 K:P 比率，并且可以通过通气组织促进泥炭氧化（氧化性营养）来利用泥炭氮。常绿杜鹃花灌木比垫状无花果灌木表现出明显更高水平的碳百分比和更低的 δ15N 值。马蹄莲（生长在沼泽高地边缘营养丰富的护城河中）具有非常高的叶片 N、K、δ15N 和 N:P 比值，表明它可能从邻近高地和/或的矿营养流中获取养分。 迅速腐烂的泥炭。化学计量分析表明，大多数物种的氮含量有限。将混合模型应用于食肉动物、非食肉动物和昆虫的 δ15N 值，估计 50% 的叶子 N 来自于狸藻的猎物，42% 的瓶子草和 41% 的茅膏菜。
Previous meta‐analyses suggested that carnivorous plants—despite access to N, P, and K from prey—have significantly lower leaf concentrations of these nutrients than noncarnivores. Those studies, however, largely compared carnivores in nutrient‐poor habitats with noncarnivores in more nutrient‐rich sites, so that the differences reported might reflect habitat differences as much as differences in nutrient‐capture strategy. Here we examine three carnivorous and 12 noncarnivorous plants in the same nutrient‐poor bog to compare their foliar nutrient concentrations, assess their patterns of nutrient limitation using leaf NPK stoichiometry, and estimate percentage N derived from prey by carnivores using a mixing model for stable N isotopes. We hypothesized that (1) carnivore leaf nutrient concentrations approach or exceed those of noncarnivores in the same nutrient‐poor habitat; (2) species in different functional groups show different patterns of stoichiometry and apparent nutrient limitation; and (3) noncarnivores might show evidence of using other means of nutrient acquisition or conservation to reduce nutrient limitation. At Fallison Bog in northern Wisconsin, carnivorous plants (Drosera rotundifolia,Sarracenia purpurea,Utricularia macrorhiza) showed significantly lower leaf percentage C and N:P ratio, higher δ15N, and no difference from noncarnivores in leaf N, P, K, and δ13C. Sedges had significantly lower leaf percentage P, percentage C, and N:K ratio, and higher K:P ratio than nonsedges restricted to theSphagnummat, and may tap peat N via aerenchyma‐facilitated peat oxidation (oxipeditrophy). Evergreen ericaceous shrubs exhibited significantly higher levels of percentage C and lower values of δ15N than mat nonericads.Calla palustris—growing in the nutrient‐rich moat at the bog's upland edge—had very high values of leaf N, K, δ15N, and N:P ratio, suggesting that it may obtain nutrients from minerotrophic flows from the adjacent uplands and/or rapidly decaying peat. Stoichiometric analyses indicated that most species are N limited. A mixing model applied to δ15N values for carnivores, noncarnivores, and insects produced an estimate of 50% of leaf N derived from prey forUtricularia, 42% forSarracenia, and 41% forDrosera.