ESPM 120 “Soil Characteristics” Fall 2007

Today Syllabus and expectations Syllabus and expectations Soils and Berkeley and You Soils and Berkeley and You Mini field trip (to Hilgard Hall) Mini field trip (to Hilgard Hall)

Syllabus and expectations– main points Schedule subject to change Schedule subject to change Basic weekly structure Basic weekly structure Ask questions, be excited Ask questions, be excited Respect each other Respect each other Have fun Have fun

Soils and Berkeley and You How are the following related to soil? Pizza Pizza Don Edwards Wildlife Refuge Don Edwards Wildlife Refuge Your house/apartment Your house/apartment

History of Pedology mid 19th Century: no scientific study of soils mid 19th Century: no scientific study of soils Soil science followed closely behind development of geology (early 19th century) and biology (Origin of Species). Soil science followed closely behind development of geology (early 19th century) and biology (Origin of Species). Two key contributors to development of Pedology Two key contributors to development of Pedology Vasili Dokuchaev (Russian geographer/mineralogist) Vasili Dokuchaev (Russian geographer/mineralogist) Eugene Hilgard (American geologist/chemist) Eugene Hilgard (American geologist/chemist)

Eugene Hilgard and Soil Science at Berkeley Born in Germany Born in Germany Raised in American frontier (Illinois) in intellectually oriented family Raised in American frontier (Illinois) in intellectually oriented family Received PhD at University of Heidelberg Received PhD at University of Heidelberg Agricultural chemistry and geology Agricultural chemistry and geology Accepted position as Assistant State Geology of Mississippi in 1855 Accepted position as Assistant State Geology of Mississippi in 1855

Hilgard in Mississippi Not a glamorous job Not a glamorous job Recognized his future with state lie not with geology but agriculture and soils 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 Produced a landmark document (next slide) with half geology and half soils

The Mississippi Report Detailed discussion of soil formation and soil chemistry Detailed discussion of soil formation and soil chemistry “soil” map of state…. “soil” map of state….

Hilgard’s Agricultural Map Analogous to modern generalized soil map Analogous to modern generalized soil map Map units based on geology and vegetation Map units based on geology and vegetation

Hilgard Moves to California Recruited by UC president in 1874 Recruited by UC president in 1874 Replaced first chair of agriculture (who was fired) 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 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) 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 Mountains, lakes, streets, buildings, journals are all named after Hilgard His influence was international, inspiring the next generation of scientists, particularly Hans Jenny…… 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) 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 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 Factors are independent of system System is small relative to surroundings System is small relative to surroundings A change in variables defines a new system A change in variables defines a new system there are essentially an infinite number of soils there are essentially an infinite number of soils

Mini Field Trip Soil Profiles Soil Profiles

Extent map Extent map Typical pedon Typical pedon Natural vegetation Natural vegetation San Joaquin Series

Next Time Chapter 1 Chapter 1 Handout Handout Study questions Study questions