Soil AtmosphereSoil Atmosphere

TemperatureTemperature

(Chapter 7)(Chapter 7)

Ch 7 OutlineCh 7 Outline

I. Section 7.8: Processes affected by soil I. Section 7.8: Processes affected by soil temperaturetemperature

II. Section 7.10 – only “soil temperature variations”II. Section 7.10 – only “soil temperature variations”

III. Section 7.11: Soil temperature controlIII. Section 7.11: Soil temperature control

I. Soil Temperature – the ProcessI. Soil Temperature – the Process

A. Plant processesA. Plant processes

B. Microbial processesB. Microbial processes

C. Freezing/thawingC. Freezing/thawing

D. PermafrostD. Permafrost

E. Heating by fireE. Heating by fire

F. Contaminant removalF. Contaminant removal

A. Plant ProcessesA. Plant Processes Seed germinationSeed germination Root functionsRoot functions

High temps=death/lifeHigh temps=death/life

Low temps=slow chemical Low temps=slow chemical and bio rxnsand bio rxns

Narrow range for optimum Narrow range for optimum growthgrowth

Figure 7.18Figure 7.18

B. Microbial ProcessesB. Microbial Processes

Biological zero=5Biological zero=5ooCC Double for each 10Double for each 10ooC riseC rise Useful for nutrient mngmt Useful for nutrient mngmt

planning/disease controlplanning/disease control

Figure 7.20

I. Soil Temperature – the ProcessI. Soil Temperature – the Process

A. Plant processesA. Plant processes

B. Microbial processesB. Microbial processes

C. Freezing/thawingC. Freezing/thawing

D. PermafrostD. Permafrost

E. Heating by fireE. Heating by fire

F. Contaminant removalF. Contaminant removal

Effects of FireEffects of Fire

Figure 7.24

II. Thermal properties of soils: temperature II. Thermal properties of soils: temperature fluctuationsfluctuations

A. SeasonalA. Seasonal

B. VerticalB. Vertical

C. DailyC. Daily

Seasonal and Vertical VariationsSeasonal and Vertical Variations

Figure 7.31

Note: daily fluctuations lag behind air temperature min and max

III. Soil Temperature ControlIII. Soil Temperature ControlA. Organic residue management=buffer A. Organic residue management=buffer

temperature extremestemperature extremes

1. forest floor1. forest floor

2. conservation tillage2. conservation tillage

Tillage EffectsTillage Effects

C4NQVP

Figure 7.34

III. Soil Temperature ControlIII. Soil Temperature ControlA. Organic residue management=buffer A. Organic residue management=buffer

temperature extremestemperature extremes

1. forest floor1. forest floor

2. conservation tillage2. conservation tillage

B. Plastic mulches=specialty useB. Plastic mulches=specialty use

1. generally increase soil temps1. generally increase soil temps

2. clear plastic > temp increase than black2. clear plastic > temp increase than black

C. Moisture controlC. Moisture control

1. more water=lower temps1. more water=lower temps

2. management=improve drainage2. management=improve drainage

ReviewReview

I. Soil Temperature – the ProcessI. Soil Temperature – the Process

II. Temperature fluctuationsII. Temperature fluctuations

III. Soil Temperature ControlIII. Soil Temperature Control

Soil WaterSoil Water

Chapter 5Chapter 5

Chapter 5 OutlineChapter 5 Outline

I. General Properties of WaterI. General Properties of Water II. Capillary ActionII. Capillary Action III. Energy ConceptsIII. Energy Concepts IV. Flow of WaterIV. Flow of Water V. Specific ExamplesV. Specific Examples