Brown forest soils

Gl (MW >5000). Most of the pyrolysis fragments found in this fraction are derived from the three general classes just mentioned. Pyrrole and methylpyrrole originate from proteinaceous material such as polypeptides as well as from single amino acids such as proline and hydroxyproline. A quantitative relationship between amino acid hydrolyzable content and pyrrole abundance was established by Bracewell (20) for some Scottish brown forest soils, and such a correlation probably could be established for water. 

Ebes Brown forest soil with clay illuviation 6.6 6.2 3.3... 

Ragaly Acidic brown forest soil with clay illuviation 4.3 3.4 3.4... 

It is somewhat surprising that so few Rn emanation power studies have been carried out on soils. The study by Delwiche (1958) on Rn release from "Great World Soil Groups" gives relative emanation powers for all but one soil. His results show clearly that the more highly weathered soils emanate more Rn and that the clay intervals emanate more than the silty and sandy intervals. Red podzolic, lateritic podzolic and solodic soils emanate the most and desert soils and western brown forest soils the least. Quantified emanation powers for soils and stream sediments are shown in Table 11-XII. 

Ten Khak-Mun., 1973. The role of microorganisms in the formation of Mn-Fe concretions in brown forest soils of the Far Bast. Dokl. Akad. Nauk USSR, 209 1203—1205 (in Russian). 

Berthelin, J., Kogblevi, A. and Dommergues, Y., 1974. Microbial weathering of a brown forest soil influence of partial sterilization. Soil Biol. Biochem., 6 393—399. 

Based on the mineralogy controlling weathering and soil development, sensitivity of ecosystem to acid deposition is assessed with a comprehensive consideration on the effect of temperature, soil texture, land use and precipitation. The results show that the most sensitive area to acid deposition in China is Podzolic soil zone in the Northeast, then followed by Latosol, Dark Brown Forest soil and Black soil zones. The less sensitive area is Ferralsol and Yellow-Brown Earth zone in the Southeast, and the least sensitive areas are mainly referred to as Xerosol zone in the Northwest,... 

Dark Brown Forest soil and Black soil are in frigid temperate conditions. The accumulated temperature of > 10 °C is about 2000, the annual mean temperature is lower than 5 °C, and the precipitation is low. These soils contain large sand and small clay fraction. Thus, the chemical weathering rates are low and critical loads are also low. 

Tamura, T., M. L. Jackson, and G. D. Sherman (1955). Mineral content of latosolic brown forest soil and a hunuc ferruginous latosol of Hawaii. Soil Sci. Soc. Amer. Proc. 19, 435-439. 

Brown forest soils — these occur in loess hilly countries and lowlands in marginal zones of chernozem areas. The basic morphology of the profile is as follows ... 

Shand et al. (1994) Soii soiution (centrifugation) Brown forest soils Scotland Upland grazed grass/clover 0-18 55-110 85-96... 

The most typical podzols are usually those formed under coniferous forests less typical are the podzol-like soils formed chiefly under deciduous forests or in a warm climate. In many areas of the United States these two types of vegetation occur in mixture and the resulting soil shows characteristics that are intermediate between the two. In other cases, where man has interfered with nature, deciduous trees may follow coniferous ones, or the reverse. The podzol-like soils are commonly referred to as either gray-brown forest soils of the Temperate Zone or red and yellow podzolic soils of the warmer regions. 

Forest soils may, for the purpose of this discussion, be divided into brown forest soils and those that are more typically podzolic. In general, the brown forest soils are those formed under predominantly deciduous vegetation and are either neutral or only slightly acid. The true podzols are formed under predominantly evergreen softwood vegetation and are often very acid. 

A typical podzol is formed under a heavy layer of organic debris consisting chiefly of needles, cones, dead twigs and branches derived from the heavy stand of coniferous trees that may have been there for many years, usually centuries (see Chapter 7). These organic residues are low in bases, unsuitable as foods for earthworms, and are resistant to decay. The result is the accumulation of a duff or mor layer, often several inches thick. The natural cycle of removal and return of soil bases, so characteristic in brown forest soils, occurs to only a minor extent. 

Bain, D.C. and Griffen, D.T. (2002). Possible effects of land use on the clay mineralogy of a brown forest soil. Clay Minerals, 37 663-670. 

Table 2. Distribution of amino acid - and nucleic acid-N in 6M HCl hydrolysates of the fractions of alkali-soluble humic substances, isolated from a brown forest soil, and separated by "salt-boundary" gel chromatography.

Zimovets, B. A., 1963. Orthoeluvial new formations of amorphous silica in brown forest soils of the Amur region. Soviet Soil Sci. 132. 

Y. Onikura, and S. Tokudome, 1965. Genesis and characteristics of brown forest soils derived... 

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