Background and aims
Freshwater nitrogen inputs are increasing globally, altering the structure and function of wetland ecosystems adapted to low nutrient conditions. Carnivorous wetland plants, Utricularia spp., are hypothesised to reduce their reliance on carnivory and increase their assimilation of environmental nutrients when the supply of ambient nutrients increases. Despite success in using stable isotope approaches to quantify carnivory of terrestrial carnivorous plants, quantifying carnivory of aquatic Utricularia requires improvement.
Methods
We developed stable isotope mixing models to quantify aquatic plant carnivory and used these models to measure dietary changes of three Utricularia species: Utricularia australis, U. gibba, and U. uliginosa in 11 wetlands across a 794 km gradient in eastern Australia. Diet was assessed using multiple models that compared variations in the natural abundance nitrogen isotope composition (δ15N) of Utricularia spp. with that of non-carnivorous plants, and environmental and carnivorous nitrogen sources.
Key results
Carnivory supplied 40 – 100 % of plant nitrogen. The lowest carnivory rates coincided with the highest availability of ammonium and dissolved organic carbon.
Conclusions
Our findings suggest that Utricularia populations may adapt to high nutrient environments by shifting away from energetically costly carnivory. This has implications for species conservation as anthropogenic impacts continue to affect global wetland ecosystems.
Data for: To Eat or Not to Eat: Novel Stable Isotope Models Reveal a Shift in Carnivory with Nutrient Availability for Aquatic Utricularia spp
Creators
Emmi Kurosawa - Southern Cross University
Naomi S Wells - Southern Cross University
Joanne Oakes - Southern Cross University
Robert Gibson - Department of Climate Change, Energy, the Environment and Water
Zachary Lyons - Southern Cross University
Publisher
figshare
Grant note
National Science Foundation (NSF) funded Limnology and Oceanography Research Exchange (LOREX) program provided by Association for the Sciences of Limnology and Oceanography (ASLO) (award #1831075, 2019-2021), The Integrative Graduate Education and Research Traineeship (IGERT) funded by NSF (award #1249946), and Nancy Goranson Endowment Fund provided by the Goranson family
Identifiers
991013396251902368
Academic Unit
Faculty of Science and Engineering; Science
Language
English
Resource Type
Dataset
Data for: To Eat or Not to Eat: Novel Stable Isotope Models Reveal a Shift in Carnivory with Nutrient Availability for Aquatic Utricularia spp