Soils Exam 1 Flashcards
Soil spatial variable
Large to micro scale concerning climatic vegetation to aggregates
Gelisols
Very cold climate
Permafrost
Slow soil formation
High organic content due to slow decomposition
Spodosols
Acid soils with thin subsurface
Form in coarse textured parent materials
Form under coniferous vegetation
Alfisols
Moderately leached forest souls
Temperate humid and subhumid regions
Very productive
Found in upper Midwest of USA
Weathering involves both
Destruction and synthesis
4 processes of soil formation
Transformation
Organic parent material
Forms where plant growth exceeds rate of decomposition
Aridisols
Light color low organic matter
High salts and minerals
Deserts
Glaciel till parent material
Material deposited directly by Glaciel ice
E horizon
Bleached almost white color, often sandy. Elucidation of clay. Fe, Al
6 functions of soil
Support plant growth Control fate of water Recycling system Modify atmosphere Habitat for organisms Engineering medium
C horizon
Un consolidated material
Mollisols
Dark, soft and if grasslands
Thick and dark
Crumb like structure
Important for agriculture
Alluvial parent material
Sediments deposited by streams and rivers and deposited into floodplains, deltas, etc
Biochemical reactions double fur every ___ degree Celsius increase in temperature
10
Degree of weathering is related to ________ rather than total precipitation?
Effective
Soil interface consists of:
45% solids
5% organic matter
O horizon
Organic materials above mineral soil
Andisols
Volcanic ash
Highly organic
High water and naturally fertile
Covers significant land in PAC NW
Eolian parent material
Silt sized material and smaller carried by wind. Volcanic ash
Lacustrine parent materials
Materials deposited when glacial out wash turns into lake. Stratified
A horizon
Topmost mineral horizon containing enough organic material to blacken. Coarse texture