Distribution in soil profile

Two groups of chemical elements can be considered related to their distribution in soil profiles. The first group includes the essential nutrients actively absorbed by vegetation and relatively tightly bound in soil organic matter (Figure 11). 

Swaine DJ, Mitchell RL. 1960. Trace-element distribution in soil profiles. J Soil Sci ll(2) 347-368. 

The distribution in soil profiles follows the general trends of soil solution circulation (Kabata-Pendias et al. 1989, Kabata-Pendias and Pendias 1991). The aim of our experiments was to examine the influence of the geological origin and the condition of soil formation on the correlation of the elements in shooting wheat (n = 550), rye in blossom (n = 485), field red clover (n = 3269) and meadow red clover in blossom... 

Fernandez C, Labanowski J, Cambier P, Jongmans AG, Van Oort F (2007) Fate of airborne metal pollution in soils as related to agricultural management I. Zn and Pb distributions in soil profiles. Eur J Soil Sci 58 547-559... 

Moreira-Nordemann LM, Sieffermann G (1979) Distribution of uranium in soil profiles of Bahia state, Brazil. Soil Science 127 275-280... 

The distribution of Al and a number of other elements in soil profiles across the W-E transect appears to be strongly dependant on climate gradients rather than significant changes in soil parent materials and soil age. This observation provides important information about the relative importance of a number of geochemical processes that are not revealed in studies at more detailed (local) scales. 

ABSTRACT This study forms part of a larger multidisciplinary environmental study of the Lower Guadiana River basin carried out by a joint Portuguese-Spanish research team. It describes the mobility of lead in soil profiles taken over varied lithologies of the Iberian Pyrite Belt and the distribution of this metal with the root, stems and leaves of three plant species native to the area (Cistus ladanifer L., Lavandula luisieri and Thymus vulgaris). Results indicate that at all sample sites the mobility of lead is very low. 

The determination of distribution pattern of various forms of both macroelements and heavy metals in soil profile is a very complicated task. We have to know the... 

Z.M. Xie, Z.H. Ye, M.H. Wong, Distribution characteristics offluoride and aluminum in soil profiles of an abandoned tea plantation and their uptake by six woody species. Environ. Int. 26 (2001) 341-346. 

Figure 14.15. Depth distribution of summed compound classes in soil profiles under Miscan-thus stands. L and Of describe organic litter layers mainly composed of the Miscanthus residues, Ah the humic mineral topsoil, and Bh an argillic subsoil horizon. Samples were taken in the years 1999 and 2000.

Huang, L.Q. and C.R. Frink (1989). Distribution of atrazine, simazine, alachlor, and metolachlor in soil profiles in Connecticut. Bull. Environ. Contam. Toxicol., 43 159-164. 

Wang, X.J., Chen, J., Zhang, Z.H., Piao, X.Y., Hu, J.D., Tao, S., 2004b. Distribution and sources of polycyclic aromatic hydrocarbons in soil profiles of Tianjin Area, People s Republic of China. Bull. Environ. Contam. Toxicol. 73, 739-748. 

Fig. 12-25. Element distributions in two profiles from bedrock to the soil A horizon in a costean across the stratiform sulphide lens at the Hcnty Fault Zone (in Profile I Ag is below the detection limit, in Profile 2 As is below the detection limit) S = soil, T = fluvioglocial sediment, B = bedrock (from Carr et al., 1986).

Factors that control the geochemistry, abundance and distribution of carbonate cements are of prime importance in the understanding and prediction of porosity-permeability variations and in tracing the geochemical evolution of pore waters during the burial of sandstones and associated sediments. Moreover, the stable isotopic composition of nearsurface, eogenetic carbonates (e.g. in soil profiles) provides important clues to the palaeoclimatic conditions (e.g. Ceding, 1984). 

Wright, J. R., Levick, R., and Atkinson, H. J. (1955). Trace element distribution in virgin profiles representing four great soil groups. Soil Sci. 19, 340-344. 

There is little information on the distribution of Mo in soil profiles. The Mo content was generally found to be higher in surface soils as compared with subsurface soils in some alluvial, black, red, and hill soils in Uttar Pradesh (Pathak, Shanker, and Misra, 1968 Misra and Misra, 1972). In the salt-affected soils of Haryana, the total Mo content decreased with depth (Gupta and Dabas, 1980), whereas in the soils of Assam and Himachal Pradesh no regular pattern of its distribution was found (Chakraborty, Sinha, and Prasad, 1982 Sharma et al., 1988). 

Figure 11.5 Vertical distribution of in soil profiles at various times after incorporation into the arable layer (0-20cm). 1 - podzoluvisol, 2 - greyzem, 3 - meadow chernozem, and 4 - typical chernozem. Source-. Kashparov et al., (2005) reproduced with permission from Elsevier.

Figure 10.3 Vertical profile of distribution in soil at the completion of the experiment. Chemicals applied as a seed treatment. [Reproduced with permission from J. D. Gile and J. W. Gillett, ]. Agr. Food Chem. 27, 1159 (1979). Copyright 1979, American Chemical Society.]...

ORGANIC MATTER DISTRIBUTION IN THE PROFILES OF VIRGIN SOILS... 

A consideration of the organic matter distribution in the profiles of our main types of virgin soils is necessary in order to understand the conditions that now exist in our agricultural soils. Although many years removed from the virgin condition, cultivated... 

The "field approach" based on metal distribution within soil profiles did not give a clear answer whether or not heavy metals were leached downwards from the surface layers. The negative result of long-term field monitoring prompted a new approach to the problem, i.e. the determination of the chemical forms of heavy metals in soils and their changes under controlled conditions. 

Typical lor the application of mobile EDRFA is the fast determination of element distributions in drilling cores or in finding hot spots in soil profiles (Fig. 9). 

Water leaves the field either as surface mnoff, carrying pesticides dissolved in the water or sorbed to soil particles suspended in water, or as water draining through the soil profile, carrying dissolved pesticides to deeper depths. The distribution of water between drainage and mnoff is dependent on the amount of water appHed to the field, the physical and chemical properties of the soil, and the cultural practices imposed on the field. These factors also impact the retention and transformation processes affecting the pesticide. 

Plant uptake is one of several routes by which an organic contaminant can enter man s food chain. The amount of uptake depends on plant species, concentration, depth of placement, soil type, temperature, moisture, and many other parameters. Translocation of the absorbed material into various plant parts will determine the degree of man s exposure—i.e., whether the material moves to an edible portion of the plant. Past experience with nonpolar chlorinated pesticides suggested optimal uptake conditions are achieved when the chemical is placed in a soil with low adsorptive capacity e.g., a sand), evenly distributed throughout the soil profile, and with oil producing plants. Plant experiments were conducted with one set of parameters that would be optimal for uptake and translocation. The uptake of two dioxins and one phenol (2,4-dichlorophenol (DCP)) from one soil was measured in soybean and oats (7). The application rates were DCP = 0.07 ppm, DCDD 0.10 ppm, and TCDD = 0.06 ppm. The specific activity of the com-... 

UNSAT-H simulates plant transpiration with a PET concept. The model partitions plants removal of soil-water between soil layers based on (1) distribution of plant roots within the soil profile for cheatgrass (an invading and weedy grass species found in dry regions of Washington State) or (2) the user may supply other functions. The user must enter soil-water parameters that describe the limits for plant extraction of water from each layer of soil. The model also uses the same daily value pattern for the LAI for each year. 

DBCP. The predictions suggest that DBCP is volatile and diffuses rapidly into the atmosphere and that it is also readily leached into the soil profile. In the model soil, its volatilization half-life was only 1.2 days when it was assumed to be evenly distributed into the top 10 cm of soil. However, DBCP could be leached as much as 50 cm deep by only 25 cm of water, and at this depth diffusion to the surface would be slow. From the literature study of transformation processes, we found no clear evidence for rapid oxidation or hydrolysis. Photolysis would not occur below the soil surface. No useable data for estimating biodegradation rates were found although Castro and Belser (28) showed that biodegradation did occur. The rate was assumed to be slow because all halogenated hydrocarbons degrade slowly. DBCP was therefore assumed to be persistent. 

Fig. 2. Distribution of organic C and microbial biomass C in the soil profile under sugarcane annually preharvest burnt or green cane harvested with retention of crop residues on the soil surface. Soils were sampled from below the plant row or in the centre of the inter-row area. Values for microbial quotient are shown in parenthesis. LSD (P<0.05) shown. (From Haynes, unpublished, 2005).

Chen QQ, Shen CD, Sun YM, Yi WX, Li ZA, Jiang MT (2005) Mechanism of distribution of soil organic matter with depth due to evolution of soil profiles at the Dinghushan Biosphere Reserve. Acta Pedologica Sinica 42(1) 1-8 (in Chinese with English abstract)... 

In soils of non-agricultural ecosystems, above ground biomass (foliar uptake) and metal cycling is considered important (see Figure 8), due to large impact on the metal distribution in the humus layer and mineral soil profile. Especially in soils of Forest ecosystems, it may affect the accumulation in the humus layer, which is considered a very relevant compartment regarding the calculation of a critical load. In these soils, however, a steady-state element cycle is assumed, which implies that mineralization, Minj, equals litterfall, Mjf. 

The vertical distribution of oil products in a soil profile depends on the fluxes and ground level of soil-ground waters, which both temporally and spatially are very dynamic. In spite of being restricted due to low water solubility, migration of oil products with natural waters in the areas of oil pollution may significantly increase the distance of lateral pollutant transport with surface and sub-surface waters. 

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