fnr soils test 2

Bulk density

Mass of soil/vol of soil(solids and pores)

Cation Exchange Formula

Sum of all exchangeable cations

What is available water capacity

the range of available water that can be stored in the soil

What is formula for soil porosity

1-(bulk density/ particle density) times 100

Available water capacity formula meaning 

field capacity minus wilting point. used for irrigation

What are the units for soil porosity

percentage

Particle density

Mass of soil/ vol of solids

\psi T=\psi M+\psi S+\psi G+\psi P

Water potential formula

Alfisols

(Alfs) moderately weathered soils

Types of horizons in Alfisols

Fragipan, plaic, Duripan

Fragipans

Dense brittle pan

Duripan

Dense, strong silica cemented Pan

Placic

very hard pan, Fe, Mn, cemented

lowercase t

Clay illuviation

Lowercase x meaning

Fragipan

Available water capacity formula

Inches of H2O/inches of soils =AWC (in/in)

Cohesion

Water molecules bonding with itself

What is soil conversion factor

SOM= SOC * 1.72

saturated hydraulic conductivity formula

Ksat=(q/A) * (L/Delta H)

Mollisols define

(olls) meaning soft moderately weathered

Parent material of mollisol

calcareous loess

What does loess mean? 

Transported by wind

What effects rate of decay

1. Temperature 

2. Organic matter (wood vs grass)

3. Water (moist soil)

4. Stage of decay

immbolization of nitrogen

nitrogen not used, woods

Categories of organic soil

1. Hummus (collid which means glue)

2. fresh residue(litter)

3. living organisms 

4. decomposing orgo matter

mobilization of nitrogen

release of nitrogen, greens, high nitrogen content 

percolation test

time it takes water to drop 1 inch in a pre-wetted hole= time/drop in water level = min/inch

Agrillic horizon in mollisols

accumulation of clay

What are the units for bulk density 

g/cm³ and g/cc

What are the units for particle density

g/cm³

What are the units for Ksat

in/h or cm/h

What does particle density help determine

soil porosity

What is base saturation formula

BS=(Ca + Mg + K + Na)

What is Ksat used for

the perc test

What are the units for cation exchange capacity

meq/100g

What is cation exchange capacity used for

soil fertility

Are earthworms beneficial or parasites

Major decomposers and use bacteria for nutrition

What kind of organisms are earthworms

hermaphrodites

What are surface species of earthworms called

Epideic species

What are the upper soil species of earthworm called

Endogeic species

What are the deep borrowing species of earthworms called

Anemic species

What are nematodes

Non segmented worms

Where do nematodes live

Maximum in A horizon and around roots

Are nematodes beneficial or parasitic

Beneficial nematodes control diseases and cycle nutrients. Mineralizing nutrients for the plants

Do nematodes provide symbiotic or parasitic

Parasitic because they damage plant cell walls

What kind or organisms are Protozoa

Single celled organisms and larger than bacteria

Where do Protozoa live

Maximum in A horizon. Around root and in humus

Are Protozoa beneficial or parasitic

Beneficial because they release nitrogen

Do protozoa form symbiotic or parasitic relationships?

They form both because not only do they feed on bacteria but also other protozoa

What kind of organisms are soil algae 

Single celled, autotrophic, cyanobacteria 

Where does soil algae live

Maximum in the A-
hor.; Around roots; On humus;
On the surface of
soil aggregates;
In spaces between
soil aggregates

Are soil algae beneficial or parasitic

??

Do soil algae  form symbiotic or parasitic relationships?

It forms symbiotic relationships by providing protection to algal cells and then host gets energy 

What type of organisms are fungi 

small cells that grow hyphae to push through soil particles 

Where do fungi live?

between soil particles, roots, and rocks

Are fungi beneficial or parasitic

They can be both. There root pathogenic fungi like Rhizoctina.  But there is mycorrhizal fungi that solubilize  phosphorus 

Do fungi form symbiotic or parasitic relationships 

in exchange for carbon from the plant, mycorrhizal fungi help solubilize phosphorus and bring soil nutrients so symbiotic

What kind of organism is bacteria

one celled organism

Where are bacteria found?

In A horizon around roots, humus, on and between soil aggregates

Are bacteria beneficial or parasitic

beneficial because it can cycle nutrients and suppress diseases

Do bacteria form symbiotic or parasitic relationships 

Nitrogen fixing bacteria form symbiotic relationships with the roots of trees and legumes

What kind of organisms are actinomycetes

large group of bacteria that grow hyphae like fungi 

Where are actinomycetes found

A horizon around roots, in humus, on top and in between soil aggregates 

Are actinomycetes beneficial or parasitic

beneficial because they decompose hard substances like cellulose and chitin 

Do actinomycetes form symbiotic or parasitic relationships 

The Frankia Family forms symbiotic with non legume plants the same way nitrogen fixing bacteria do 

Sodium Absorption ratio formula

..

SAR units

mmol/L

What is SAR formula used for

irrigation

Aridisols

(id) meaning dry