HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Cirmo, C.P. Articles by Bowes, K. Search for Related Content PubMed Articles by Cirmo, C.P. Articles by Bowes, K. GeoRef GeoRef Citation Agricola Articles by Cirmo, C.P. Articles by Bowes, K.

DIVISION S-10-WETLAND SOILS

Chemical Fluxes from Sediments in Two Adirondack Wetlands

Effects of an Acid-Neutralization Experiment

^a Dep. of Geology, State Univ. of New York College at Cortland, Cortland, NY 13405 USA
^b Dep. of Civil and Environ. Engineering, Syracuse Univ., Syracuse, NY 13244 USA
^c Dep. of Art and Archaeology, Princeton Univ., Princeton, NJ 08544 USA

cirmoc{at}snycorva.cortland.edu

As a strategy of acid deposition mitigation, the application of neutralizing agents to hydrologic source areas has received substantial attention for the past decade. To compare mass balance–determined fluxes with field measurements at the sediment–water interface, we used benthic enclosures to determine chemical fluxes from the sediments of a reference beaver pond (no chemical treatment) and a beaver pond within the watershed of an acid-neutralization experiment (CaCO₃ treatment). Baseline O₂–consumption rates, the effects of reacidification, and the effects of CaCO₃ and CaCl₂ additions were determined. Oxygen consumption rates in pond sediments were higher in the CaCO₃–treated wetland, indicating stimulation of microbial activity and the subsequent enhancement of organic-matter decomposition. In the reference wetland, anoxia was followed by the sequential consumption of NO^-₃ and SO^2-₄, basic cation (C_B) and Fe²⁺ release, and the production of acid-neutralizing capacity (ANC), while the release of Ca²⁺ from cation-exchange sites dominated ANC in the treated wetland. Reacidification of CaCO₃–treated sediments caused an immediate increase in Al concentration in the water column, initially in the inorganic monomeric form (Al_IM), followed by increasing concentrations of the organic monomeric form (Al_OM). Hydrolysis of Al inputs from upland drainage, complexation of Al with dissolved organic carbon (DOC), and the formation of less toxic Al_OM were all observed. Our evidence reveals that these sediments may act as sinks for inputs of strong acid anions (e.g., SO^2-₄ and NO^-₃) from atmospheric deposition, and as sinks and transformation zones for Al associated with acidic upland drainage.

Abbreviations: Al_IM, inorganic monomeric form • Al_OM, organic monomeric form • ANC, acid-neutralizing capacity • C_B, basic cation • DOC, dissolved organic carbon • DO, dissolved oxygen • Exp., Experiment • SI, saturation index