| Abstract: | Abstract Alkaline‐soluble, acid‐precipitable organic matter from the Ah and Bm horizons of Chernozemic soils developed on four parent materials in each of three soil zones was analyzed for total and carboxyl acidity, and methoxyl groups. The values are expressed as meq/g dry ash‐free organic matter. Total acidity generally was higher in the Black Chernozems than in the Brown Chernozems and higher in the Bm horizon than in the Ah horizon. The distribution of carboxyl acidity between the Ah and companion Bm horizons of individual soils appeared to be related to texture and rainfall. The. methoxyl group content of the Brown Chernozems was larger than that of the .Dark Brown Chernozems, which in turn had a larger methoxyl group content than that of the Black Chernozems. It was concluded that the organic matter in the Ah horizons of the Brown Chernozems was not as humified as that of the Black Chernozems. The pH value and a minimum clay content are possible determining factors as to the amounts of methoxyl carbon present. |
