World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0000164544
Reproduction Date:

Title: Pedogenesis  
Author: World Heritage Encyclopedia
Language: English
Subject: Pedology (soil study), Soil science, Soil morphology, Pedology, Technosol
Collection: Ecological Succession, Pedology
Publisher: World Heritage Encyclopedia


Pedogenesis (from the Greek pedo-, or pedon, meaning 'soil, earth,' and genesis, meaning 'origin, birth') is the science and study of the processes that lead to the formation of soil (soil evolution)[1] and first explored by the Russian geologist Vasily Dokuchaev (1846 – 1903), the so-called grandfather of soil science, who determined in 1883[2] that soil formed over time as a consequence of climatic, mineral and biological processes, which he demonstrated using the soil forming equation:

Soil = f(C, PM, O) × time (where C = climate, PM = parent material, O = biological processes)

In 1941, the Swiss scientist Hans Jenny expanded Vasily Dokuchaev equation by adding topographic relief as a factor and separating the biological processes into the fauna and flora coming up with the equation:

Soil = f(C, PM, R, O, V) × time (where C = climate, PM = parent material, R = relief/topology, O = fauna, V = flora)

Pedogenesis is a branch of pedology, whose other aspects include the soil morphology, classification (taxonomy) of soils, and their distribution in nature, present and past (soil geography and paleopedology).


  • Climate 1
  • Organisms 2
  • Parent material 3
  • Examples 4
  • See also 5
  • Notes 6
  • References 7


Climate regulates soil formation. Soils are more developed in areas with higher rainfall and more warmth. The rate of chemical weathering increases by 2-3 times when the temperature increases by 10 degrees Celsius. Climate also affects which organisms are present, affecting the soil chemically and physically (movement of roots).


The organisms living in and on the soil form distinct soil types. Coniferous forests have acidic leaf litter that form soils classed as inceptisols. Mixed or deciduous forests leave a larger layer of humus, changing the elements that are either leeched or accumulated in the soil, and thereby forming soils classed as alfisols. Prairies have very high humus accumulation, creating a dark, thick A horizon characteristic of mollisols.

For example, three species of land snails in the genus Euchondrus in the Negev desert are noted for eating lichens growing under the surface limestone rocks and slabs (endolithic lichens).[3] They disrupt and eat the limestone.[3] Their grazing results in the weathering of the stones, and the subsequent formation of soil.[3] They have a significant effect on the region: the total population of snails is estimated to process between 0.7 and 1.1 metric ton per hectare per year of limestone in the Negev desert.[3]

Parent material

The rock from which soil is formed is called parent material. The main types are: aeolian sediments, glacial till, glacial outwash, alluvium, lacustrine sediments and residual parent material (coral or bedrock).

Pedologists see soil formation or soil properties as a function of regional climate, biota, topography, parent material, time and other variables.[4]


A variety of mechanisms contribute to soil formation, including siltation, erosion, overpressure and lakebed succession. A specific example of the evolution of soils in prehistoric lake beds is in the Makgadikgadi Pans of the Kalahari Desert, where change in an ancient river course led to millennia of salinity buildup and formation of calcretes and silcretes.[5]

See also


  1. ^ Stanley W. Buol, F.D. Hole and R.W. McCracken. 1997
  2. ^ Dokuchaev, V.V. 1883. Russian Chernozem.
  3. ^ a b c d Odling-Smee F. J., Laland K. N. & Feldman M. W. (2003). "Niche Construction: The Neglected Process in Evolution (MPB-37)". Princeton University Press. 468 pp. HTM, PDF. Chapter 1. page 7-8.
  4. ^ Jenny, Hans (1994). Factors of soil formation: A System of Quantitative Pedology (PDF). New York: Dover.  
  5. ^ C. Michael Hogan. 2008


  • Stanley W. Buol, F.D. Hole and R.W. McCracken. 1997. Soil Genesis and Classification, 4th ed. Iowa State Univ. Press, Ames ISBN 0-8138-2873-2
  • C. Michael Hogan. 2008. Makgadikgadi, The Megalithic Portal, ed. A. Burnham [2]
  • Francis D. Hole and J.B. Campbell. 1985. Soil landscape analysis. Totowa Rowman & Allanheld, 214 p. ISBN 0-86598-140-X
  • Hans Jenny. 1994. Factors of Soil Formation. A System of Quantitative Pedology. New York: Dover Press. (Reprint, with Foreword by R. Amundson, of the 1941 McGraw-Hill publication). pdf file format.
  • Ben van der Pluijm et al. 2005. Soils, Weathering, and Nutrients from the Global Change 1 Lectures. University of Michigan. Url last accessed on 2007-03-31
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.