Soil systems transportable elements

Fungi clearly play significant direct and indirect roles in effecting and modulating transport of a wide range of elements in soil systems. The principal transport modes that they are implicated in can be summarized as dispersion, concentration, inter-organism and bulk transfer (Fig. 3.5). 

As reactive P is transported through the terrestrial system, it is assimilated into plants and subsequently into the rest of the biosphere (2). Although many elements are required for plant life, in many ecosystems P is the least available and, therefore, limits overall primary production (Schindler, 1977 Smith et al., 1986). Thus, in many instances the availability of P influences or controls the cycling of other bioactive elements. When organisms die, the organic P compounds decompose and the P is released back into the soil-water system. This cycle of uptake and release may be repeated numerous times as P makes its way to the oceans. 

Soil solution is the aqueous phase of soil. It is in the pore space of soils and includes soil water and soluble constituents, such as dissolved inorganic ions and dissolved organic solutes. Soil solution accommodates and nourishes many surface and solution reactions and soil processes, such as soil formation and decomposition of organic matter. Soil solution provides the source and a channel for movement and transport of nutrients and trace elements and regulates their bioavailability in soils to plants. Trace element uptake by organisms and transport in natural systems typically occurs through the solution phase (Traina and Laperche, 1999). 

To facilitate fundamental understanding of the linkage of trace elements in soils with plant—animal—human—environment systems and related geomedical problems and to provide practical solutions to their deficiency and toxicity problems, it is essential to promote research on the relationship between soil physicochemical-biological interactions and the impacts on the transformation, transport, bioavailability, toxicity, and fate of trace elements in the terrestrial environment. 

System XVIII, XIX human being (XVIII) human society (XIX) development of agriculture, industry and transport (XIX) accumulation of wastes in soil (40), air (43) and natural waters (44). Increasing accumulation of pollutants in the environment. We have to remember here that from the biogeochemical point of view, pollution is the destruction of natural biogeochemical cycles of different elements. For more details see Chapter 8 EnvironmentalBiogeochemistry . 

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