One-day rate measurements for estimating net nitrification potential in humid forest soils


TitleOne-day rate measurements for estimating net nitrification potential in humid forest soils
Publication TypeJournal Article
Year of Publication2006
AuthorsRoss, D, Fredriksen, G, Jamison, AE, Wemple, B, Bailey, SW, Shanley, JB, Lawrence, GB
JournalForest Ecology and Management
Volume230
Issue1-3
Pagination91 - 95
Date Published7/2006
ISSN03781127
Abstract

Measurements of net nitrification rates in forest soils have usually been performed by extended sample incubation (2–8 weeks), either in the field or in the lab. Because of disturbance effects, these measurements are only estimates of nitrification potential and shorter incubations may suffice. In three separate studies of northeastern USA forest soil surface horizons, we found that laboratory nitrification rates measured over 1 day related well to those measured over 4 weeks. Soil samples of Oa or A horizons were mixed by hand and the initial extraction of subsamples, using 2 mol L−1 KCl, occurred in the field as soon as feasible after sampling. Soils were kept near field temperature and subsampled again the following day in the laboratory. Rates measured by this method were about three times higher than the 4-week rates. Variability in measured rates was similar over either incubation period. Because NO3− concentrations were usually quite low in the field, average rates from 10 research watersheds could be estimated with only a single, 1-day extraction. Methodological studies showed that the concentration of NH4+ increased slowly during contact time with the KCl extractant and, thus, this contact time should be kept similar during the procedure. This method allows a large number of samples to be rapidly assessed.

URLhttp://www.sciencedirect.com/science/article/pii/S0378112706002714
DOI10.1016/j.foreco.2006.04.022
Short TitleForest Ecology and Management
Status: 
Published
Attributale Grant: 
IRWE
Grant Year: 
Year4 (Select this year for NEW RACC products)