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In France, andic soils mainly occur in the Massif Central (andic and other volcanic soils >5000 km 2 ), and on the Vosges and the Morvan Hercynian massifs. In the Massif Central, Silandosols on recent pyroclastics are distinguished from Aluandosols on older Mio-Pliocene lavas. After a brief introduction to the parent materials, soil characterisation, survey, genesis, properties and land use are reviewed in two periods: from 1960 to 1979, and from 1980 to 2000. Soil distribution is related schematically to topo-climatic sequences, comparing recent pyroclastics to older volcanic lavas. An udic or perudic soil moisture regime is the primary factor in Andosol genesis in France. Silandosols occur only on recent pyroclastics and Aluandosols on old lavas after reworking by glacial erosion from a mantle of loose and pre-weathered materials. The anthropic impacts include accelerated erosion and changes in carbon content. |
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