There are a variety of elements that influence soil development. A. By analyzing the chemical composition of developed soil, it is possible to determine the location of the geological substrate from which the parent material was originally derived. B. Both topography and the types of organisms present in the soil as it develops determine its nutrient level. C. The length of time that is takes to develop high-quality soil is determined by humidity levels, the makeup of parent materials, and patterns of water flow and erosion. D. The weathering process is strongly influenced by temperature and its variation, the nature of the water flow, and by the acids carried in the water. E. Where soil material is regularly subject to rapid and extreme variations in temperature and water content, certain biogeochemical reactions necessary for soil formation cannot take place. F. Because high humidity speeds up both leaching processes and erosion, soils in humid regions take much longer to reach equilibrium than soils in dry regions, and are seldom as fertile.