Competition does not explain the absence of a carnivorous pitcher plant from a nutrient-rich marsh

作者：Abbott Matthew J^*; Brewer J Stephen

来源：Plant and Soil, 2016, 409(1-2): 495-504.

DOI：10.1007/s11104-016-3011-1

• Abiotic stress
• Carnivorous plants
• Competitive inferiority
• Hypoxia
• Sarracenia alata (Pale Pitcher Plant)
• Wetlands

Why is the carnivorous pitcher plant, Sarracenia alata Wood, largely absent from eutrophic habitats? Two hypotheses are addressed: (1) Sarracenia alata is competitively excluded by non-carnivorous plants where resource availability is high and (2) S. alata cannot tolerate stressful conditions unrelated to competition in a eutrophic wetland.
We tested these hypotheses using a reciprocal transplant experiment to compare the performance of Sarracenia alata in eutrophic marsh and oligotrophic bog, crossed with soil source and neighbor removal treatments. Multiple environmental co-variables were also measured to identify factors responsible for transplant performance.
Survivorship was 46.5% greater in the bog than in the marsh, and a significant proportion of the variation was explained by higher redox potential in the bog. Transplants were not negatively impacted by neighbors in either community.
Results lead us to reject the competitive inferiority hypothesis and provide support for a hypothesis of inadequate stress avoidance. We suggest that a lack of tolerance of abiotic stressors, as opposed to competition, be given greater consideration when explaining the distributions of terrestrial hydrophytic carnivorous plants.

• 出版日期2016-12