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ESPM 120 “Soil Characteristics”. Fall 2007. Today. Syllabus and expectations Soils and Berkeley and You Mini field trip (to Hilgard Hall). Syllabus and expectations– main points. Schedule subject to change Basic weekly structure Ask questions, be excited Respect each other Have fun.
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ESPM 120“Soil Characteristics” Fall 2007
Today • Syllabus and expectations • Soils and Berkeley and You • Mini field trip (to Hilgard Hall)
Syllabus and expectations– main points • Schedule subject to change • Basic weekly structure • Ask questions, be excited • Respect each other • Have fun
Soils and Berkeley and You How are the following related to soil? • Pizza • Don Edwards Wildlife Refuge • http://www.fws.gov/desfbay/habitats.htm • Your house/apartment
History of Pedology • mid 19th Century: no scientific study of soils • Soil science followed closely behind development of geology (early 19th century) and biology (Origin of Species). • Two key contributors to development of Pedology • Vasili Dokuchaev (Russian geographer/mineralogist) • Eugene Hilgard (American geologist/chemist)
Eugene Hilgard and Soil Science at Berkeley Born in Germany Raised in American frontier (Illinois) in intellectually oriented family Received PhD at University of Heidelberg Agricultural chemistry and geology Accepted position as Assistant State Geology of Mississippi in 1855
Hilgard in Mississippi Not a glamorous job Recognized his future with state lie not with geology but agriculture and soils Produced a landmark document (next slide) with half geology and half soils
The Mississippi Report Detailed discussion of soil formation and soil chemistry “soil” map of state….
Hilgard’s Agricultural Map Analogous to modern generalized soil map Map units based on geology and vegetation
Hilgard Moves to California Recruited by UC president in 1874 Replaced first chair of agriculture (who was fired)
Berkeley when Hilgard arrived…. Despite cultural isolation Hilgard seized opportunity to expand College of Agriculture (now CNR) and make soils a national issue
Hilgard and John Wesley Powell (USGS) Prodded JW Powell to start a national soil survey program (later adopted by USDA)
Hilgard and his legacy…. Mountains, lakes, streets, buildings, journals are all named after Hilgard His influence was international, inspiring the next generation of scientists, particularly Hans Jenny……
Hans Jenny and Soil Formation Soils form predictably in response to environmental factors (Dokuchaev ~ 1880) Hans Jenny (1920’s to 1930’s) transformed conceptual model to a more quantitative theory following tenets of physical chemistry
State Factor Equation Soil = f (initial conditions, external conditions, time) or, based on field observation Soils = f (climate, biota, topography, parent material, time, …. )
Key Concepts of State Factor Theory Factors are independent of system System is small relative to surroundings A change in variables defines a new system there are essentially an infinite number of soils
Mini Field Trip • Soil Profiles
http://soils.usda.gov/technical/classification/osd/index.htmlhttp://soils.usda.gov/technical/classification/osd/index.html
San Joaquin Series • Extent map • Typical pedon • Natural vegetation
Next Time • Chapter 1 • Handout • Study questions