SOURCES OF ACIDITY IN SOME FORESTED UDULTS.
Three sources of soil acidity (bicarbonate leaching; base-cation accumulation in aboveground wood, roots, and forest floor; and acid atmospheric deposition) were evaluated in relation to exchangeable acidity of three forested Udults in Tennessee. The Udults have low effective CEC (CEC//e), from 2. 4 to 3. 7 cmol//c kg** minus **1. In the three soils, H** minus from bicarbonate leaching averaged 0. 60 kmol//c ha** minus **1 yr** minus **1 over 2 yr. In five forest stands, 30 to 80 yr in age, H** plus from accumulation of excess base (EB) cations left bracket EB equals (Ca plus Mg plus K) - (P plus S) right bracket in aboveground wood, roots, and forest floor averaged 1. 11 kmol//c ha** minus **1 yr** minus **1. Variations in H** plus inputs were caused by annual differences in the hydrologic cycle and by stand differences due to nutrient-cycling and soil-chemistry effects. In these forest ecosystems, sources of soil acidity from annual bicarbonate leaching and cation accumulation appeared to exceed atmospheric inputs.
Volume / Issue
Start / End Page
International Standard Serial Number (ISSN)
Digital Object Identifier (DOI)