Mercury distribution in Typha angustifolia biomass in a St. Lawrence River wetland

Session: Wetland Restoration in the Great Lakes Basin: Research and Innovation (3)

Evie Brahmstedt, Clarkson University, [email protected]
Carla Crespo, University of Puerto Rico, [email protected]
Thomas Holsen, Dept. Civil & Environ. Eng., Clarkson University, [email protected]
Michael Twiss, Clarkson University, Dept. of Biology & Great Rivers Center, [email protected]

Abstract

Atmospheric mercury (Hg) has deposited in the St. Lawrence River (SLR) watershed over the past 60 years, coinciding with a stable water level regulation plan, which allowed for Typha spp. to dominate riparian wetlands by out competing other vegetation. A recent change in water level regulation, Plan 2014, calls for water level fluctuations, which are predicted to increase biodiversity of the river ecosystem by reducing Typha spp. and allowing for increased vegetation diversity. It is expected that 29% of Typha spp. will be lost. However, Typha spp. do bioaccumulate Hg. Here, the ability for Typha angustifolia in a protected embayment wetland to accumulate Hg was assessed. Total Hg content in wetlands was estimated to predict the risk for future Hg mobilization. The bioconcentration factor between hydric soil and T. angustifolia roots was low (1.61 ± 1.46) and the translocation factor between roots and leaves was 0.22 ± 0.12, indicating the majority of Hg in accumulates in T. angustifolia roots at concentrations slightly greater than in the hydric soil. The contribution of T. angustifolia and hydric soil to the total Hg in the wetland and the 29% loss throughout the upper SLR will be reported in terms of total Hg.

Twitter handle of presenter
@ESBrahmstedt