| Abstract Detail
Ecological Section Abel, Josh [1], Graham, Jeremy [2], Vitt, Dale H. [3]. Sphagnum and ericaceous shrub responses to nitrogen and phosphorus additions in a boreal ombrotrophic bog. Canada contains one third of the earth’s boreal forest which consists of a patchwork landscape of forested uplands, lakes, and peatlands. Ombrotrophic bogs in Alberta, Canada, are peatlands isolated from surface water or groundwater inputs and receive nutrient inputs from within the ecosystem or from atmospheric deposition. Currently, most bogs in the Oil Sands Administration Area (OSAA) of Alberta receive ~2.0 kg nitrogen (N) ha-1 yr-1 from atmospheric N deposition which is expected to increase with further oil sands development. It was previously understood that ombrotrophic bogs were N limited due to low atmospheric N deposition. Recent studies; however, suggest that ombrotrophic bogs in the OSAA are not N limited by atmospheric N deposition and have accumulated upwards of 25 times more N that can be contributed through atmospheric deposition alone. Phosphorous (P) addition experiments can be used to test for N limitation. We hypothesized that P would limit peat moss, Sphagnum fuscum, and ericaceous shrub production in the bog while N would not be a limiting nutrient. This nutrient limitation hypothesis was tested experimentally by adding NH4NO3 and H3PO4 as wet deposition at seven treatment concentrations that consisted of two control treatments (control and water only control), two N only treatments (10 kg N ha-1 yr-1 and 20 kg N ha-1 yr-1), a P only treatment (7 kg P ha-1 yr-1), and a low N and P treatment, and a high N and P treatment. We examined the growth responses of S. fuscum and ericaceous shrubs following one field season (May-July) of N and P fertilizations. The N and P additions significantly increased S. fuscum linear growth. Sphagnum fuscum and ericaceous shrub net primary production was not influenced by N or P. These results represent the first year of a three year field study; therefore, observing few effects suggests no immediate responses of N and P additions on plant production. Log in to add this item to your schedule
1 - Southern Illinois University-Carbondale, Plant Biology, Southern Illinois University, Carbondale, IL, 62901, USA 2 - Southern Illinois University Carbondale, Plant Biology, 1125 Lincoln Drive, Life Science II, room 420, Carbondale, Illinois, 62901, United States 3 - Southern Illinois University, Plant Biology, Carbondale, IL, 62901, USA
Keywords: Sphagnum ericaceous shrubs nitrogen deposition phosphorus addition net primary production.
Presentation Type: Poster:Posters for Sections Session: P Location: Hall D/The Shaw Conference Centre Date: Monday, July 27th, 2015 Time: 5:30 PM Number: PEC015 Abstract ID:487 Candidate for Awards:Ecological Section Best Graduate Student Poster |