Soil orders

Table 8-4 USDA soil orders with common ecosystems or environments in which they occur and shown in...

Soil order Unique features Ecosystem/environment... 

See "Keys to Soil Taxonomy" (Soil Survey Staff, 1998) for complete criteria for each soil order. 

Figure 8-5 shows soil orders that form in relation to climate and vegetation along a transect from the poles to the equator along with processes occurring in the soil. In this conceptual diagram, it is assumed that there is a uniform parent material, similar topography and... 

Soil Order Entisols Gelisols Inceptisols Spodosols Inceptisols Alfisols... 

Plate 3 shows a map of dominant soil orders for the entire world. Although this map necessarily lacks detail due to its scale, the relationship between soils and the biosphere is evident. Different terrestrial ecosystems are correlated with climatic conditions and different soils are correlated with both. For example, Mollisols are common in areas where there are prairies or steppes a result of grasses as the dominant vegetation and low, seasonal rainfall. Spodosols occur where coniferous forests dominate and the climate is cold and wet. Comparing Fig. 8-5 and Plate 3 carefully will show how strong this correlation is for the entire Earth. 

Melanization, responsible for the Mollisol soil order, 2. Pedoturbation, responsible for the Vertisol soil order, and 3. Argilluviation (mobilization and transport of clay to an accumulation horizon) responsible for the Alfisol order. 

Soil order Suborder Africa Asia Australia Europe South Central North Global... 

Fenton T.E. Mollisols. In Pedogenesis and Soil Taxonomy, II. The soil orders, L.P. 

Nettleton W.D., Peterson F.F. Aridisols. In Pedogenesis and Soil Taxonomy. II. The Soil Orders, P. Wilding, N.E. Smeck, G.F. Hall, eds. Amsterdam Elsevier, 1983. 

International Society of Soil Science, has a system that includes 26 soil groupings. There are many other systems including those developed by Canada, France, the former Soviet Union, China, Australia, and other countries. Each recognizes a different number of major soil groups or soil orders. 

The three kinds of soils used in the present study represent a broad national geographical area. Three soils were selected from the eleven soil orders found in the US to determine the effect of soil adsorptive capacity on the reduction of contaminant toxicity in leachates prepared from COMs. The selected soils are discussed below. 

Army. 1985a. Comparison of extraction techniques and solvents for explosive residues in soil. Order no. A1-5-R0001-XX-A1-48. Aberdeen Proving Ground, MD U.S. Army Toxic and Hazardous Materials Agency. Document no. AD A2205888. 

Oospores often several to many, free zoospores produced in attached zoosporangia mostly saprobic in water or soil.Order Saprolegniales... 

Biome DOC DON (mg N1) DOC (kg ha DON OO) Soil Order Location Data source... 

Soil orders Alf, alfisol And, andisol Cam, cambisol Gley, gleysol Hist, histosol Inc, inceptisol Moll, mollisol Ox, oxisol Spod, spodosol Ult, ultisol. 

Spodosols are one of the 12 soil orders in the USDA Soil Taxonomy. The soil orders, and their key properties, are listed in Table 4. The distribution of the soil orders in the world is illustrated in Figure 14. With respect to Spodosols, which are common to the NE USA, Canada, Scandinavia, and Russia, the key... 

Figure 13 Soil organic C depth in three contrasting soil orders (source Soil Survey Staff, 1975).

Table 4 The soil orders of the US Soil Taxonomy and a brief definition of their characteristics.

Figure 14 The global distribution of soil orders (source http //www.nrcs.usda.gov/technical/worldsoils/mapindx/).

Culminating a long-term international effort, the Soil Survey staff of the Soil Conservation Service (U S. Department of Agriculture) developed a Comprehensive Soil Classification System (CSCS) for world soils (Soil Survey Staff 1975). The CSCS defines soil classes strictly in terms of soil morphology, rather than based on soil genesis. A brief explanation of the 10 soil orders in the CSCS is given in Table 7.4 (see also Bodek et al. 1988). Their temporal relationships are considered in Fig. 7.6. 

TABLE 7.4 A simplified description of the 10 soil orders as defined in the Comprehensive Soil Classification System (CSCS)... 

Table 6.1. Average organic carbon contents of several soil orders in temperate and tropical regions (to obtain approximate SOM values, multiply by 1.7)a...

Table 9.2. Charge characteristics of various soil orders...

Soil Order Horizon pHsalt Charge cmolc Negative kg-1 Positive... 

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