 For example, the Gray Luvisol great group includes 12 subgroups; Orthic Gray Luvisol is the typical expression of Gray Luvisols, and other subgroups are intergrades to the Chernozemic order (Dark Gray Luvisol), Podzolic order (Podzolic Gray Luvisol), Gleysolic order (Gleyed Gray Luvisol), Solonetzic and Gleysolic orders (Gleyed Solonetzic Gray Luvisol), etc.Families are based on parent material properties and soil climate.For example, the Orthic Gray Luvisol subgroup includes soils of a wide range of texture (gravelly sandy loam to clay), different mineralogy and different temperature and water regime.