Soils fauna

Doeksen, J. and Van der Drift, J. (Editors), 1963. Proceedings of Colloquium on Soil Fauna, Soil Microflora and Their Relationdiips. North-Holland, Amsterdam, 453 pp. 

Handbook of Photosynthesis, edited by Mohammad Pessarakli Chemical and Isotopic Groundwater Hydrology The Applied Approach, Second Edition, Revised and Expanded, Emanuel Mazor Fauna in Soil Ecosystems Recycling Processes, Nutrient Fluxes, and Agricultural Production, edited by Gero Benckiser Soil and Plant Analysis in Sustainable Agriculture and Environment, edited by Teresa Hood and J. Benton Jones, Jr. 

Long-term grasslands provide plenty of organic matter for humus formation. If the soil is not acidic or waterlogged, the soil fauna and flora create humus and the subsequent useful development of a porous crumb and granular structure. Porosity encourages root growth and the uptake of soil nutrients. 

Soil is a relatively thin layer of unconsolidated matter on the surface of the earth, in which there is biological activity. The bulk of most soil consists of a mixture of extremely small, loose particles of minerals and organic matter the mineral particles are derived from the weathering of rocks the organic matter from the dead remains of living organisms (Rowell 1994 Limbrey 1975). The composition and texture of the soil are altered by human habitation humans change the natural flora and fauna of entire areas, their activ-... 

McGrath S.P. Adverse effects of cadmium on soil microflora and fauna. In Cadmium in Soils and Plant, McLaughlin M.J., Singh B.R., eds. Netherlands Kluwer Academic, 1999. 

Truncated ecological gradients Loss of soil fauna... 

Particulate organic matter LF — 2-18% of organic C, 1-16% of total N SSF - 20 45% of organic C and 13-40% of total N Partially decomposed plant litter isolated by density fractionation (LF) or sieving (SSF). Substrate and centre for soil microbial activity, short-term reservoir of nutrients, food source for earthworms and other soil fauna and focci for formation of water stable aggregates. 

Cadmium residues, in mg/kg dry weight (ppm) in soil, flora, and fauna collected near two zinc smelters in Palmerton, Pennsylvania... 

Parmelee, R.W., R.S. Wentsel, C.T. Phillips, M. Simini, and R.T. Checkai. 1993. Soil microcosm for testing the effects of chemical pollutants on soil fauna communities and trophic structure. Environ. Toxicol. Chem. 12 1477-1486. 

In terrestrial ecosystems, atrazine effectively inhibits photosynthesis in target weeds and can also affect certain sensitive crop plants. Atrazine metabolites are not as phytotoxic as the parent compound. Degradation is usually rapid, although atrazine can persist in soils for more than one growing season. Soil fauna may be adversely affected shortly after initial atrazine application at recommended levels, but long-term population effects on this group are considered negligible. 

Acute biological effects of the Chernobyl accident on local natural resources were documented by Sokolov et al. (1990). They concluded that the most sensitive ecosystems affected at Chernobyl were the soil fauna and pine forest communities and that the bulk of the terrestrial vertebrate community was not adversely affected by released ionizing radiation. Pine forests seemed to be the most sensitive ecosystem. One stand of 400 ha of Pirns silvestris died and probably received a dose of 80 to 100 Gy other stands experienced heavy mortality of 10- to 12-year-old trees and up to 95% necrotization of young shoots. These pines received an estimated dose of 8 to 10 Gy. Abnormal top shoots developed in some Pirns, and these probably received 3 to 4 Gy. In contrast, leafed trees such as birch, oak, and aspen in the Chernobyl Atomic Power Station zone survived undamaged, probably because they are about 10 times more radioresistant than pines. There was no increase in the mutation rate of the spiderwort, (Arabidopsis thaliana) a radiosensitive plant, suggesting that the dose rate was less than 0.05 Gy/h in the Chernobyl locale. 

The accident at the Chernobyl, Ukraine, nuclear reactor on April 26, 1986, contaminated much of the northern hemisphere, especially Europe, by releasing large amounts of radiocesium-137 and other radionuclides into the environment. In the immediate vicinity of Chernobyl at least 30 people died, more than 115,000 others were evacuated, and the consumption of locally produced milk and other foods was banned because of radiocontamination. The most sensitive local ecosystems were the soil fauna and pine forest communities. Elsewhere, fallout from Chernobyl measurably contaminated freshwater, marine, and terrestrial ecosystems, including flesh and milk of domestic livestock. Reindeer (Rangifer tarandus) calves in Norway showed an increasing frequency of chromosomal aberrations that seemed to correlate with cesium-137 tissue concentrations tissue concentrations, in turn, were related to cesium-137 in lichens, an efficient absorber of airborne particles containing radiocesium and the main food source of reindeer during winter. A pattern similar to that of reindeer was documented in moose (Alces) in Scandinavia. 

Hurt RA, Qiu X, Wu L, Roh Y, Palumbo AV, Tiedje JM, Zhou J (2001) Simultaneous recovery of RNA and DNA from soils and sediments. Appl Environ Microbiol 67 4495 1503 Ingham ER, Troymow JA, Ames RN, Hunt HW, Morley CR, Moore JC, Coleman DC (1986) Trophic interactions and nitrogen cycling in a semi-arid grassland soil. Part 2. System responses to removal of different groups of soil microbes or fauna. J Appl Ecol 23 615-630... 

Soil fauna, including invertebrates, like nematodes and earthworms. Effects are connected with biodiversity, productivity and biomass changes ... 

Possible effects on soil hfe, plants (phytotoxicity) and on ground water are of concern in all types of ecosystems. Food quality criteria are, however, of relevance for arable land only, whereas possible secondary poisoning effects on domestic animals or terrestrial fauna are relevant in grassland and non-agricultural land. A final critical limit can be based on the most sensitive receptor. Even though effects vary for each metal, soil microbes and soil fauna are generally most sensitive. 

Here we will describe the methods that are used to derive critical limits for soil, based on direct ecotoxicological effects on microorganisms and plants. The indirect approaches (food web models) to derive critical limits for soil based on critical limits for terrestrial fauna such as MPC values for target organisms will be also considered. 

As we have discussed earlier, the critical limit to be used depends on what we want to protect. In terrestrial ecosystems this can be soil fauna, the soil vegetation or the human beings that use ground water for drinking water or that consume crops that are grown on the soil. In aquatic ecosystems, the critical limits are connected with concentration of dissolved species in water. 

Another approach is to determine the effect of contaminating organic compounds on soil fauna such as worms. Although this can be informative, it is often impossible to differentiate between the effects of active uptake and passive uptake or simple exposure [4],... 

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