Soil (final) Flashcards
Soil erosion control measures
In zero till
Shelterbelts
Control structures
Soil erosion
It is estimated that topsoil is eroding faster than it forms on more than one third of the world’s croplands
Cover crops
Any crop grown primarily to provide ground cover to improve soil properties, rather than providing a harvestable yield. It is normally grown in the time period between regular crops, although it may be seeded in the preceding crop
Hydrologic cycle
Continuous circulation of water within the earth’s hydrosphere
Groundwater
GW is an important water source
Cone of depression
When a substantial amount of water is withdrawn from a well, the water table around the well is lowered in a conical in shape
Geological work of Groundwater
GW typically contains carbonic acid
Water “picks up; carbonic acid as rain passes the air and as the GW percolates through zones of decaying plant material
When GW contacts limestone the carbonic acid reacts with calcite and forms calcium bicarbonate
Caverns
Dissolving process slowly creates cavities and gradually enlarges them into caverns
When water table is lowered, cavities are filled with air and the following can form
Stalactites
Stalagmites
Columns
What are the 10 longest rivers in the world?
Nile
Amazon
Yangtze
Mississippi
Yenisel
Yellow River
Ob
Rio de la Plata
Congo
Amur
What are the 10 longest rivers in Canada?
Mackenzie
Yukon
Saint Lawrence
Nelson
Slave
Columbia
Saskatchewan
Peace
Churchill
South Saskatchewan
Soil
The connection of natural bodies on the earth’s surface supporting or capable of supporting plants
Three discriptors of our local soil
Rich
Saturated
Dense
Soil formation
Parent material
Soild matter making up of soil
Influences soil property (texture, PH, fertility)
Residual soils
Remain at site of formation
Transported soils
Transported from site of parent
Time
Weathering for a short time (parent material strongly influence the characteristics of material and soil)
Biota
Plants and animals supply organic matter to the soil
Microorganisms play an active role in in the decay of plant and animal remains
Topography
Length and steepness of slopes significantly affect the amount of erosion and the water content of soil
Soil horizons
Vertical differences divide soil into layers
Soil profile
Verticle section through all soil horizons
O horizon
Upper layer of O
Lower
High biodiversity
A horizon
Mostly mineral material, some humus, biological activity still high
E horizon
Contains little organic material
B horizon
Where much of the material removed from the E horizon by eluviation isn deposited
C horizon
Partly altered parent material (easily identifiable)
Not considered true soil
What is nitrogen fixation?
The process by which atmospheric nitrogen is converted by either a natural or an industrial means to a form of nitrogen
Ideal agricultural soils
Loamy
Includes equals parts in sand, silt, and clay
Rills
Smaller channels
Gullies
Deeper channels created as rills enlarge
Topsoil, how we conserve it
Cover cropping, composting, conservation tillage, and organic fertilization
