The fractionation of the organic matter, including nitrogen, of certain soils and its relation to their quality

Abstract

1. The proximate analysis of a number of widely differing soil profiles has been carried out, employing a slight modification of the scheme used by Waksman and Shewan. This included a nitrogen fractionation with water and acid, similar to that of Waksman and of Shewan. It was supplemented by ammonia and nitrate estimations. The data are expressed on the basis of total organic matter.2. The soils ranged in quality from peat and forest soils to grassland profiles. This gradation of quality was brought out by many of the figures of the proximate analysis. The better quality soils are associated with:(a) a lower average content of fats and waxes, hemicelluloses and cellulose;(b) a rapid decrease in cellulose with increasing depth;(c) higher total nitrogen and various fractions, including higher ammonia and nitrate and a higher ratio of nitrate to ammonia;