Test media solid samples and aqueous extracts

4 Test media solid samples and aqueous extracts 

Soil ecology generally addresses biota at the surface of soil (e.g. plants) or the top soil layer (about one to two metres). Soil is not abiotic below this depth but 

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. 

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