Nitrate Production in the Field by Incubating the Soil in Polyethylene Bags

Abstract

Nitrate production was studied in the field by incubation of the soil in pint polyethylene bags during the 1958-59 winter season. This technique permits the diurnal changes in soil temperature to be taken into consideration in studying microbial processes, such as nitrification.Laboratory studies showed that the rate of nitrification in soil contained in the bags was equal to that contained in ventilated bottles. The bags were tightly closed against the soil and secured with rubber bands. Only slight losses in soil moisture occurred during a 6-week period of incubation. Polyethylene is permeable to oxygen and carbon dioxide. No nitrate difused through the polyethylene bags in a 24-week period.Field studies were made using bags of soil buried at a depth of 4 inches for periods of 1 to 6 weeks. Although soil temperatures at this depth were never below freezing, they varied sufficiently to result in considerable changes in the rate of nitrate production.This technique should also prove to be of considerable value in evaluating nitrification in climates where the soil is frozen or at a temperature near freezing during a portion of the year.

Forest canopy uptake of atmospheric nitrogen deposition at eastern U.S. conifer sites: Carbon storage implications?

“…Net N mineralization (defined as net ammonification plus net nitrification) was determined in the O horizon (forest floor) and top 10 cm of the B horizon (mineral soil) at the Howland Forest from 1993 to 1995 using the in situ buffed soil bag technique [Eno, 1960]. In this method, 20 pairs of samples were collected from each horizon at 6-week intervals throughout the growing season.…”

Winter and growing season nitrogen mineralization from fall-applied composted or stockpiled solid dairy manure

“…Of the field methods, the buried bag technique of Lentz and Lehrsch (2012a), as adapted from Eno (1960), gives representative estimates of in situ net N mineralized for the region's irrigated soils (Westermann and Crothers 1980;Meek et al 1994;Lentz et al 2011). The technique utilizes polyethylene film, permeable to O 2 and CO 2 but nearly impermeable to water vapor, to encase moist soil collected from, then replaced within a few hours into cavities in the soil profile.…”

Comparison of Available Soil Nitrogen Assays in Control and Burned Forested Sites

“…These methods allow determination of potential N availability; however, they are carried out in ideal environmental conditions and may overestimate site processes. Eno (1960) introduced the in situ buried bag incubation technique. While this method incorporates in situ soil temperature variations into estimates of net N mineralization and nitrification, soil moisture remains unchanged during the incubation period.…”