|MadSci Network: Agricultural Sciences|
Well, Iím not too surprised that you had difficulty finding information on the effects of gunpowder on soil Ė I had difficulty finding anything myself. The only people who routinely analyze for gunpowder are forensic scientists who are looking for minute traces on clothing or other surfaces.
The problem with gunpowder is that it is not made of very durable stuff. As you may know- itís made out of KNO3 (saltpetre), carbon and sulfur. KNO3 is an inorganic salt and dissolves quite easily in water and can be washed away. NO3- is actually a nutrient that can be taken up by plants and microbes. This just leaves carbon and sulfur that can oxidize over time. Besides, all of the ingredients: carbon, nitrate, potassium and sulfur occur naturally in soil in one form or another which would make it hard to be sure what you were seeing was from gunpowder. Some of the products of a gunpowder reaction might settle on the soil in a battlefield (in the same way that they leave residue on criminalís clothing) but most of these chemicals would be in incredibly small amounts and could be broken down over time by microbes and environmental conditions. Bacteria can break down all sorts of things, as in this story.
All this did get me thinking about soil and munitions in general, however. A site here in Ithaca, NY has just gotten some press as the soil is contaminated with lead from a gun factory. Some people are also concerned about the contamination of soil by lead shot used for skeet. I suppose the same might apply to Civil War ammunition. The references are at the end of this post.
Ecology and Biogeochemistry
P.S. If you are generally interested in geology and history there is an interesting book I heard about called "Battling the Elements" by Harold Winters that describes how battles relate to geology and meteorology.
Lead Shot in Soils:
Distribution and phytoavailability of lead in a soil contaminated with lead shot
Rooney CP, McLaren RG, Cresswell RJ
WATER AIR AND SOIL POLLUTION,1999, Vol 116: (3-4) pp.535-548
The environmental and ethical implications of lead shot contamination of rural lands in North America
J. OF AGRICULTURAL & ENVIRON. ETHICS 1997, Vol 10, Iss 1, pp. 41-54
The Effects Of Lead Shot Deposition On Soils and Crops at a Clay Pigeon Shooting Site in Northern England
MELLOR A; MCCARTNEY C
SOIL USE AND MANAGEMENT 1994, Vol 10, Iss 3, pp 124-129
The Fate of Lead in Soils - The Transformation of Lead Pellets In Shooting-Range Soils
JORGENSEN SS; WILLEMS M
AMBIO 1987, Vol 16, Iss 1, pp 11-15