Abstract Title: | Investigating Mercury in Soils of a Rural Salt Marsh in Massachusetts, USA: spatial and temporal patterns, speciation, source origins, and mobility |
Presenter Name: | Buyun Du |
Company/Institution: | University of Massachusetts, Lowell |
Session: | Mercury in Marine Ecosystems |
Day and Session: | Thursday 28th July - Session Four |
Start Time: | 15:00 UTC |
Co-Authors: | Buyun Du,Ting Wang,Inke Forbrich,Jun Zhou,Joshua Landis,Prentiss Balcom,Elsie Sunderland,Daniel Obrist |
Abstract Information :
Salt marsh soils are biogeochemical hot spots and develop through a combination of inorganic sedimentation facilitated by tidal inundation and organic matter accumulation from productive vegetation. Here, we investigate what controls internal Hg cycling. We took cores (105 cm depth) in the Plum Island Sound salt marsh in Massachusetts, and analyzed them for total Hg (THg) and Methyl-Hg (MeHg), mobility, fallout radionuclide chronometers, and auxiliary measures. Results show total THg concentrations of 212ñ201 æg kg-1 (meanñSD; range of 6-860 æg kg-1), which strongly exceed nearby sediments (82 æg kg-1) and result in high pools sizes of Hg sequestered in these soils (83ñ73 mg m-2). MeHg concentrations average 1.2ñ2.4 æg kg-1 (0.1-14.3 æg kg-1), largely lack correlations with THg (p>0.05), and generally account for