Luvisols form on flat or gently sloping landscapes under climatic regimes that range from cool temperate to warm Mediterranean.
Occupying just over five percent of the total continental land area on earth, they are found typically in west-central Russia, the United States, central Europe, the Mediterranean basin, and southern Australia.
Luvisols are technically characterized by a surface accumulation of humus overlying an extensively leached layer that is nearly empty of clay and iron-bearing minerals.
Below the latter lies a layer of mixed clay accumulation that has high levels of available nutrient ions comprising calcium, magnesium, sodium, or potassium.
Luvisols are often associated with Cambisols and Albeluvisols are a related FAO soil group also exhibiting clay migration.2. From the classification system of the Food and Agriculture Organization, FAO.
3. Etymology: from Latin luere, "to wash".