1. Soil chemistry on Watershed 1: 1998 - 2014
Chris Johnson
Syracuse University

2. Wollastonite Addition: W1, October 1999

3. Motivation and Hypotheses
“Replace” Ca depleted from soils by:
Acid rain
Successional vegetation growth
Soil Hypotheses:
Wollastonite application will result in increased total and exchangeable Ca in W1 soils.
Increases in exchangeable Ca will be accompanied by decreased exchangeable acidity (Al + H).
…causing soil pH and base saturation to increase.
Soil chemical change will occur over many years, in a “chromatographic” manner.

4. Changes in Exchangeable Ca in W1 Soils:
Exchangeable calcium increased in all sampled layers after wollastonite treatment.
Exchangeable acidity (Al+H) declined in all layers, though Ca increases generally exceeded acidity declines.
Data reflect a progressive downward migration of Ca in the soil. Significant changes were detected in the Oi+Oe horizon in 2000, while changes did not occur until 2002 in the Oa horizon, and in the mineral soil.

5. Changes in Soil pH and Base Saturation

6. Is Watershed 1 Losing Soil Organic Matter?

7. Is Watershed 1 Losing Soil Organic Matter?
It does not appear to be a sampling issue.

8. Is Watershed 1 Losing Soil Organic Matter?

9. Possibilities Worms? [They are out there.]
Higher OM solubility at higher pH? [There has been little or no change in soil solution DOC.]
Enhanced decomposition?
Treatment-related? [Groffman sees few differences between W1 and (west of) W6.]
Climate-related? [W6 OM mass may be declining as well.]

10. Is Watershed 1 Losing Soil Organic Matter?
Woods Lake Data: Melvin et al. (2013)

11. “Punch List” Digestions/total elemental analysis (esp. Ca)
Organically bound Al (CuCl2 extraction)
Total Acidity (buffered BaCl2 extraction)