Geochemistry Gradients

Abstract

Gradient is an important concept in ecology and landscape study. For example, in ecology gradients are frequently studied in relation to the change in plant cover types or in response to some environmental factor; in soil science the concept is often used in relation to relief or natural drainage. Two kinds of gradient are commonly distinguished: (1) continuous gradients within which the rate of change is gradual and relatively uniform; and (2) discontinuous gradients along which abrupt changes occur.

“Catena: A sequence of soils of about the same geological age, derived from similar parent materials and occurring under similar climatic conditions but having different characteristics due to variations in relief and in natural drainage.”

R. L. Donahue, J. C. Shickluna, and L. S. Robertson, Soils: An Introduction to Soils and Plant Growth, 3rd ed. (Englewood Cliffs, N.J.: Prentice Hall, 1971), p. 508.