Soil temperature Flashcards
Processes affected by soil temp
-growth rate, seed germination, root functions
- microbial processes
-freezing/thawing
-soil heating by fire
Are plants more sensitive to soil temperature or air temp?
Soil temp
Plants that cool soil temp for completion of life cycle
- tulips
- winter wheat, rye
Corn seeds planted in soil below 7-10 degree celsius will _____
rot and die
Some weed species have Better germination when?
soil temp fluctuates widley
What causes winter burn?
Look at notes
Biological zero
no biological processes under 5 degree celsius
“winter burn”
Air temp is higher then soil temp which causes photorespiration to not be as effective
Yellowing or purpling in corn
Low phosphorus uptake
Every ___ microbial respiration roughly doubles
10 degree celsius
Optimal microbial activity
35-40 degree celsius
Nitrification optical around ___ negligible below __
30 degree Celsius 10 degree celsius
Freezing and thawing causes ____
improves structure in structureless soils and can degrade structure in well-aggregated soils
Frost heaving
Upwards selling of soil during freezing conditions caused by presence of ice as it grows towards the surface
Detriments of frost heavings
-pushes up roots
- breaks roads
- pushes pillars out if not placed below frost line
Texture of soil less susceptible to heaving
gravel and pure sand
Soils more susceptible to heaving
silts and loams
burning plant material can create a _______ within soil
water repellent
Infiltration rate is ________ in burned areas compared to unburned areas
usually lower
After burning what may occur
mudslides
Factors that influence soil temp
-climate
-albedo (color)
-slope aspect
-soil cover
-soil moisture
Albedo
fraction of incident radiation that is reflected by the land surface
Factors that affect soil albedo
-soil color
-surface roughness
_______ is the primary source of energy to heat soils
solar radiation
