FW 5350 - Outline

Syllabus

Handouts

Lectures

I. Introduction

II. Soil Environment

A. What is Soil?

B. Composition

C. Influences on Microorganisms

1. Water

a. Climate

b. Texture

c. Impervious layers

d. Topography

e. Organic matter

2. Oxygen

3. Temperature

a. Water

b. Climate

c. Color

d. Surface cover

4. Nutrients

a. Availability classes

(1) Total

(2) Exchangeable

(3) Solution

b. Controlling factors

(1) Minerals

(2) Climate

(3) Soil age

(4) CEC

5. pH

a. Effects on soil organisms

(1) nutrient availability

(2) aluminum and hydrogen

(3) vegetation

b. Factors affecting soil pH

(1) minerals present

(2) soil texture

(3) climate

(4) vegetation

6. Organic Matter

a. Hetetrophic vs autotrophic

b. Humus

c. Forest floor layers

d. Factors affecting OM levels

(1) biomass produced

(2) decomposition rate

(a) type of OM

(b) climatic factors

D. Spatial Variations

1. Sample location

2. Soil depth

3. Replication

E. Movement of Microorganisms in Soil

1. Microorganisms in soil

a. Filtering

b. Adsorption

2. Isoelectric point

3. Cation effect

4. Microbial specificity

5. Movement through soil

a. Active

b. Mass flow

c. Diffusion

d. Roots

e. Soil animals

f. Growth

III. Bacteria

A. Abundance and Distribution

1. Numbers

2. Distribution Pattern

B. Environmental Influences

1. Water and Oxygen

2. Temperature

3. pH

4. Nutrients and Organic Matter

C. Bacteria Grouping

1. Taxonomically

2. Morphologically

3. Nutritionally

4. Ecologically

D. Methods

1. Qualitative

2. Elective Culture

3. Quantitative

a. Direct counts

b. Plate counts

c. Most probable number

IV. Actinomycetes

A. General

B. Distribution and Abundance

C. Environmental Influences

1. Water

2. Temperature

3. pH

4. Nutrients and Organic Matter

D. Taxonomy

E. Activity in Soil

V. Fungi

A. General

B. Taxonomy

1. Phycomycetes

2. Ascomycetes

3. Basidiomycetes

4. Fungi Imperfecti

5. Mycelia Sterilia

C. Fungal Structure in Soil

1. Hyphae

2. Rhizomorphs

3. Chlamydospores

4. Sclerotia

5. Spores

D. Observation and Isolation Methods

E. Abundance and Distribution

F. Environmental Influences

1. Water

2. pH

3. Temperature

4. Organic Matter

G. Activity in Soil

VI. Soil Algae

VII. Protozoa

VIII. Viruses

IX. Soil Fauna

A. Populations

1. Habitat

2. Numbers

B. Earthworms

1. Food Preferences

2. Soil pH

3. Water/Aeration

4. Soil Horizons

C. Ants and Termites

D. Other Soil Fauna

E. Methods

1. Arthropods

a. Heat Funnel

b. Pit Traps

2. Earthworms

X. Organic Matter Decomposition

A. Carbon Nutrition

1. Heterotrophs

a. Aerobes

b. Facultative anaerobes

c. Anaerobes

2. Autotrophs

B. Assimilation

C. Mineralization/Immobilization

D. Decomposition of Soil Organic Matter

E. Decomposition of Added Organic Matter

1. Environmental Factors

2. % Nitrogen

3. C/N Ratio

4. Carbon Substrate

5. Microbial Populations

F. Humus Formation

G. Methods of Measurement

1. Weight Loss

a. Litter bags

b. Core sampling

2. Substrate Change

a. Concentration or weight

b. Physical properties

3. CO₂ Evolution

4. Microbial Populations

XI. Carbon Cycle

A. Cellulose

B. Hemicellulose

C. Lignin

D. Hydrocarbons and Pesticides

XII. Nitrogen Cycle

A. Mineralization

1. Ammonification

a. Significance

b. Organisms Involved

c. Factors

d. Soil pH Changes

e. NH₃ Volatilization

f. Management Implications

2. Nitrification

a. Significance

b. Organisms Involved

c. Factors

d. Management Implications

3. Methods

B. Denitrification

1. Significance

2. Organisms Involved

3. Factors

4. Management Implications

5. Methods

C. Nitrogen Fixation

1. Nonsymbiotic

a. Organisms Involved

b. Factors

c. Management Implications

2. Symbiotic

a. Legumes

b. Non-Legumes

3. Management Implications

4. Methods