Species polluted soil

Functionally defined species in hea vily polluted soils... 

Small mammals (e.g., moles, mice, and voles) and certain bird species that live or nest in subsurface burrows may inhale volatile pollutants that are evaporated out of the soil as a vapor. This pathway is likely to be significant only in those cases where poor ventilation allows vapors to collect and concentrate and where the receptor spends a lot of time (e.g., when nesting) in such a poorly ventilated space. There is, however, little information available about how to quantify this exposure pathway. Small mammals are more likely to be significantly exposed to pollutants that have been taken up in their food items (e.g., plants, soil invertebrates) or through incidental ingestion of polluted soil particles. 

Revis NW, Osborne TR, Holdsworth G, et al. 1989. Distribution of mercury species in soil from a mercury-contaminated site. Water Air Soil Pollut 45(1-2) 105-114. 

J.G. Bundy, G.L. Paton, and C.D. Campbell, Combined Microbial Community Level and Single Species Biosensor Responses to Monitor Recovery of Oil Polluted Soil, Soil Biol. Biochem. 36(7), 1149-1159, July (2004). 

The condensed phosphates or polyphosphates are another important class of inorganic phosphates. In these compounds, two or more phosphate groups bond together via P - O - P bonds to form chains or in some cases cyclic species. In soils and waters polyphosphates generally account for only a small part of the total P content. However, these species are very reactive and in many places they are responsible for anthropogenic pollution of natural water, for instance, by detergents. The polyphosphates are formed also in reactions between orthophosphates of mineral fertilizers and soil organic matter and can be leached to surface waters (Kudeyarova and Bashkin, 1984 Kudeyarova, 1996). 

Within the defined areas, critical loads are calculated for all major combinations of tree species and soil types (receptors) in the case of terrestrial ecosystems, or water biota (including fish species) and water types in case of freshwater ecosystems. These combinations include the great variety of different ecosystems, the sensitivity of which to both acidification and eutrophication inputs by atmospheric pollutants differs greatly, determining the necessary reduction needs when CDs are exceeded by modern deposition levels. 

To date, little work has been cited in the literature with respect to arsenic speciation of polluted soil. A feasibility study on the identification and monitoring of arsenic species in polluted soil and sediment samples (Thomas etal. 1997) has been reported. In this study, polluted soil samples were extracted in phosphoric acid media using an open vessel microwave-assisted extraction system. The determination of arsenic species was investigated using an on-line system involving HPLC-ICP-MS system. The speciation was performed to identify As(III), As(V) and monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). The proposed method had the potential to form the basis of a routine procedure for monitoring the behaviour of arsenic species in soils. This extraction procedure was recently applied to contaminated... 

Aqueous extracts. Various bioassay protocols are available for testing soil elutriates or leachates. Historically these have previously been available for aquatic tests. However, it may be inappropriate to project effects generated with aquatic species to soil organisms or ecosystems. With the development of whole soil bioassays, the use of elutriate or leachate tests focuses now on the prediction of threats to groundwater (leaching of toxicants) or surface water (contaminant run-off). Tests using aqueous extracts address pollutants soluble in water, and therefore are a measure of mobile toxicants. 

Feeding behaviour, ubiquity, and the ability to accumulate various materials make earthworms useful species for soil pollution monitoring. Two of these substances are mercury and cadmium, which are highly toxic and non-essential for life. Both metals are proved to accumulate in earthworms in concentrations much higher than in the soil they inhabit [15-19]. 

Liquid wastes containing plutonium and other actinide elements may be detoxified by biological tteatment using Citrobacter species, isolated from metal-polluted soil (Plummer and Macaskie 1990). Metals in their trivalent state were most amenable to biodegradation. 

Heavy metal and radionuclide concentrations in soils increase due to man-made pollution. One of the first entry points of such elements into plant ecosystems is the rhizosphere, defined as the soil under the biological, physical and chemical influence of roots. Arbuscular mycorrhizal (AM) fungi, symbiotic microorganisms associated with the roots of many plant species, provide a direct link between soil and roots and affect metal transfer to plants. The present chapter includes recent laboratory work and some research aspects stiU to be adressed on the contribution of AM fungi to plant metal uptake. The necessity to develop new and adapted approaches, such as compartment devices and root-organ cultures, to separate AM to root contribution to metal uptake is emphasized. Available data may be difficult to compare because they were obtained under different experimental conditions. However, they suggest that the transfer of heavy metals from AM fungi to plants may be metal specific. Further research should focus on the mechanisms involved in reduced or improved uptake of metals by mycorrhizal plants, on AM tolerance to metals and radionuclides and on AM functional diversity in polluted soils. AM contribution to metal uptake should also be quantified to include data in models of plant uptake. 

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