You are here

Ellison Abstract- 2007 Butler and Ellison

Printer-friendly version

Butler, J. L. and A. M. Ellison. 2007. Nitrogen cycling dynamics in the carnivorous northern pitcher plant, Sarracenia purpurea. Functional Ecology 21: 835-843. 


  1. In nutrient-poor environments, plants employ many strategies to acquire and recycle scarce nutrients. Predictable relationships among a variety of leaf traits, including leaf nitrogen (N) suggest that how plants obtain, use, store and re-use N is a major component of plant fitness. The northern pitcher plant, Sarracenia purpurea, receives nitrogen from multiple sources: NH4 and NO3 dissolved in precipitation; N mineralized from captured prey; the scant N in saturated peat; and N remobilized from storage. In two greenhouse experiments, we examined N cycling in S. purpurea and consider how these dynamics relate to prior observations that this carnivorous plant has an unusually low photosynthetic rate for its tissue N content.
  2. In the first experiment we assessed assimilation, translocation, storage and remobilization of 15N supplied to pitchers and roots. In the second experiment, we examined how 15N assimilated by the first pitcher produced at the start of the growing season contributed to the production and maintenance of subsequent pitchers, roots and rhizomes.
  3. Patterns of N cycling were similar at the individual-leaf and whole-plant level. Pitchers assimilated 55%–69% of available 15N and served as both the largest sink for newly assimilated N (> 90% of the 15N assimilated during 2004) and the largest source of N remobilization the following spring. In contrast, N assimilated by roots was low and accounted for 2·5% of the overall S. purpurea N budget. Sarracenia purpurea used both stored N and newly-acquired N throughout the growing season. The importance of stored N decreased throughout the growing season as newly assimilated N contributed more to later pitcher production.
  4. Our detailed mechanistic analysis of nitrogen cycling dynamics of S. purpurea suggests why this plant has a low photosynthetic rate for its tissue N content. Excess nitrogen is stored for future use, and production of new pitchers is primarily aimed at enhancing prey capture rather than increasing photosynthetic tissue.

 [ Read the full text ]