| Abstract Detail
Ecological Section Tyrrell, Christopher D. [1], Chambers, Patricia A. [2], Culp, Joseph M. [3]. Phenotype, not phylogeny, drives tissue nutrient concentrations in aquatic plants. Aquatic plants incorporate nitrogen and phosphorus from the substrate into their aboveground tissues and, upon senescence, often leach these nutrients into the water. This process effectively "pumps" nutrients from the substrate into surface waters and can amount to substantial quantities annually. The amount leached by an individual plant is related to its tissue nutrient concentration, but these concentrations are influenced by several factors including morphology and species evolutionary history. Morphology, however, is itself often linked to species identity confounding our ability to understand the relative importance of phenotype vs. phylogeny to tissue nutrients. We compared the influence of growth form and species identity on aquatic angiosperm tissue nutrient composition using phylogenetic and experimental approaches. Examination for phylogenetic signal identified significant autocorrelation with morphology but not with nutrient concentrations. Experimental manipulation of morphology within three aquatic plant species showed consistent differences in tissue nutrients among species but divergent differences between phenotypes. The terrestrial form of emergent species had lower tissue nutrient concentrations than the aquatic form, but the terrestrial form of submerged species had higher concentrations than the aquatic. We conclude that variation in tissue nutrient concentrations is more attributable to expressed growth form than evolutionary history, therefore environmental factors that affect plant morphology, such as water level fluctuation, may alter aquatic plant driven nutrient cycling. Log in to add this item to your schedule
1 - Milwaukee Public Museum, Botany Department, 800 W Wells St, Milwaukee, WI, 53233, USA 2 - Environment Canada, Water Science & Technology, 867 Lakeshore Rd, Burlington, ON, L7S 1A1, Canada 3 - Environment Canada, Water Science & Technology, 10 Bailey Dr, Fredericton, NB, E3B 5A3, Canada
Keywords: Macrophyte Biochemistry ecology Aquatic.
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: PEC022 Abstract ID:1279 Candidate for Awards:None |