Carnivorous plants: the role of N-15 in tracing nitrogen dynamics in the prey-plant-soil-aquatic continuum

Carnivorous plants have access to several potential sources of nitrogen, including root uptake, predation, litterfall, atmospheric deposition and defecation by mutualistic animals. Our aim was to assess the relative importance of different N sources so as to better understand the ecology of these physiologically diverse plants that include many genera and species inhabiting terrestrial and aquatic environments worldwide. Plant physiology and habitat were the major determinants of the relative importance of N source. Our secondary aim was to examine protocarnivorous plants that do not fit the exact definition for carnivory. Several protocarnivorous plants were classified as carnivorous based on specialised trapping mechanisms, isotopic data and mixing models. Several carnivorous plants can transfer their functions of prey capture and digestion to mutualistic animal partners, which is termed ecological outsourcing. Outsourcing arthropod prey capture and digestion to mutualistic bats is a beneficial strategy for the carnivorous plant Nepenthes hemsleyana.

Automated summary

The study aimed to assess the relative importance of different nitrogen sources for carnivorous plants and to better understand their ecology. It was found that plant physiology and habitat were the main determinants of nitrogen source importance. Additionally, some protocarnivorous plants that didn't fit the exact definition for carnivory were classified as carnivorous, and it was discovered that some carnivorous plants can outsource prey capture and digestion to mutualistic animal partners.