Title

Long-term analysis of responses of soil solution and stream water of Watershed 1 at Hubbard Brook to the experimental addition of wollastonite

Date of Award

December 2014

Degree Name

Master of Science (MS)

Department

Civil and Environmental Engineering

Advisor(s)

Charles T. Driscoll

Keywords

Acidification, Liming, Soil solution, Stream water

Subject Categories

Engineering

Abstract

On October 1999, forty-five metric tons of wollastonite (CaSiO3) were applied to Watershed 1 at the Hubbard Brook Experimental Forest in New Hampshire, USA. with the objective of restoring the calcium that have been depleted from soil exchange complex by chronic inputs of acid deposition. After the treatment, the concentrations and fluxes of calcium, dissolved silica, and ANC significantly increased and the concentrations and fluxes of inorganic monomeric aluminum significantly decreased in both soil solution and stream water in all sub-watersheds of W1. The treatment improved the conditions of acidification and aluminum toxicity in stream water in W1. In particular, stream water in the lowest part of the watershed showed some alleviation of conditions of acidification and aluminum toxicity. Approximately 4.7% of the added calcium from the wollastonite treatment was exported from W1 in streamwater by the end of 2010. Meanwhile, about 730 kg/ha of the added calcium was either transported to lower mineral soil horizons as particulate wollastonite or dissolved calcium (31.1 kg/ha), contributing to increases in the pool of total calcium in the soil, or taken up by vegetation and incorporated into internal calcium cycling in W1. This experimental wollastonite addition was an effective engineering tool to mitigate the acidification of ecosystem and restore the calcium status in this base-poor watershed.

Access

Surface provides description only. Full text is available to ProQuest subscribers. Ask your Librarian for assistance.

This document is currently not available here.

Share

COinS