NRES 255 Final Exam

If you wanted to estimate the rate of saturated flow in two different soils, you would want to compare their

% macro porespace

Urea

(NH2)2CO 45-0-0

Diammonium phosphate (DAP)

(NH4)2HPO4 18-46-0

At wilting point, the soil water potential of a soil is _____, while at field capacity, the soil water potential of a soil is ____

-15 bars, -0.3 bars

What depth would you sample if this field was for pastures and lawns

0-4

What depth would you sample if this was a forest soil

0-6

Given the soil's native vegetation, what depth would you soil sample?

0-6"

Given this soil description what depth would you soil sample?

0-6"

What depth would you sample if this field was conventionally tilled

0-8 (tillage)

The gram atomic weight of Mg2+ is 24 grams per mole. The weight of Mg required to provide 1 cmole of + charge would be

0.12 grams 24/2= 12= 0.12 g

What are two potential benefits of a high CEC?

1. Reduces groundwater contamination 2. Buffers against pH changes 3. Nutrient holding sink 4. Ion exchange

What is the drinking water maximum contaminant level (MCL) set by the EPA

10 ppm Nitrate-N

A soil containing 5% organic matter would be expected to release how much available N per acre per year? (Assume OM:N Ratio = 20:1, 2% mineralization =/year)

100 lbs (2000000)(0.05)(1/20)(0.02)= 100 or (20)(5)= 100

A soil at pH 3 has ______ times as many H+ in solution as one at pH 6

1000 6-3= 3 increases by increments of 10 > 100 > 1000

Given the Munsell color notation, 10 YR 5/3:

10YR is the hue, 5 is the value, and 3 is the chroma.

How many subsamples would you need per composite sample

12-15

How many subsamples should be taken to provide a reliable composite soil sample to send to a soil testing lab AND what is the maximum number of acres that the composite sample should represent when sampling by type?

15 subsamples - 15 acres

How many tons of manure (0.5% N) would you need to apply to your soil if the soil test recommendation was 150 lbs of nitrogen per acre

15 tons 150/0.005/2000= 15

If the T value for a soil is 4 T/A/YR, how long would it take to remove the top 6-7 inches of topsoil if 50 tons/acre/year were lost each year?

20 years (2000000/50)/ (2000) = 20

How many lbs/acre of fertilizer with an analysis of 0-0-60 would you need to apply if 120 lbs/acre of the nutrient, K2O, is needed?

200 lbs/acre 120/0.60= 200

Critical C:N ratio

25:1

If you were sampling by soil type, approximately how many composite samples would you need for the drummer silty clay loam?

3-4

If you were sampling using the grid sampling method, how many composite samples would you need for this 80 acre field?

32 80/2.5= 32

How many acres are in the parcel described above

40

Soil buffering capacity changes with soil properties. Assuming each of the following has the same type of clay, which soils tends to have the highest buffering capacity?

5% OM + silty clay loam

The range of Chlorophenol red indicator is 4.8 to 6.4. The range of Bromothymol blue indicator is 5.8 to 7.4. What is the actual pH when the blue reads 7.0 and the red reads 6.4?

7.0

A soil containing 3600 lbs of Ca2+ per acre furrow slice would contain how many cmolc of Ca/kg of soil. (Atomic weight of Ca2+ = 40 g/mole)

9 cmolc/kg 3600/400= 9

The soil horizon with the largest population of microorganisms would be the

A horizon

Universal Soil Loss Equation (USLE) Give an example for C: Given an example for P:

A: Annual Soil Loss R: Rainfall Erosivity L: Slope Length C: Vegetative Cover K: Soil Erodibility S: Slope Steepness P: Erosion Control Practices C examples: examples of cropping (mono, rotate) and tillage systems (fall/spring/mulch/no-till) P examples: conturing and terracing

Which of the following is isomorphic substitution creating CEC.

Al substitutes for Si in the tetrahedral sheet at the time of formation

What was the likely parent material at Tappawingo Park?

Alluvium

Primary element in the octahedral sheet?

Aluminum

As Elsa traverses the frozen tundra landscape, in the high northern latitudes towards the mythical Ahtohallan in search of the origins of her powers, what soils should she expect to find?

Arendels

A soil horizon with clay accumulation is called a/an

Argillic horizon

Yoda - a fine-loamy, mixed, superactive, frigid Aridic Paleustalf a) What is the subgroup? b) Is Yoda one of the 2 most common soil orders in Indiana?

Aridic Paleustalf Yes

What technique/method would enable you to extract macro-organisms/invertebrates/arthropods from soil

Burlese Funnel

What two factors of the soil loss equation could be most easily adjusted by the individual land owner

C and P

Which of the following does not result in soil acidification?

CaSO4

Nitrogen deficiency

Chlorosis (pale green-yellow leaves) of the older leaves (starts at tip in grass, v along midrib in corn)

Boron deficiency

Chlorosis in younger leaves, high pH soils

Given the textural triangle below, what is the soil texture for a soil containing 30% sand, 35% silt, and 35% clay

Clay loam

You have a soil with pH of 4.5. You want to grow a tree which thrives at a pH of 6.5. You look in your garage and find 4 containers:

Container A: Ca(OH)2

Which of these soils would likely have the lowest bulk density?

Cryofolists

Vader - a coarse-loamy, isotic, mesic Vitrandic Dystroxerept a) What is the great group? b) Is the Vader a [ younger or older ] soil than the Yoda?

Dystroxerept Younger

Potassium deficiency

Edges of leaves roll, turn brown at edge and advances in, stunted plants, common in muck soils

The taxonomic class of the Eastport soil series is a Mixed, frigid Spodic Udipsamments. What is the soil order of this series?

Entisol

Rank the following soil orders Alfisol, Entisol, Inceptisol, Oxisol, Ultisol, from youngest (least weathered) to the oldest (most weathered):

Entisol, Inceptisol, Alfisol, Ultisol, Oxisol

IIIe IIs IIw

Erosion root-zone limitations (acidity, density, shallowness, solum, stoney, sandy) wetness

What is the oxidation state of the iron

Fe3+

What is the parent material of the C horizon?

Glacial Outwash

Which of the following does not result in soil acidification

Gypsum (CaSO4) application

Treble or Triple Super Phosphate (TSP) is made from

H3PO4 and rock phosphate

Magnesium deficiency

Interveinal chlorosis, starts in older leaves, low pH

Potassium Sulfate

K2SO4 0-0-50

The most common ingredient fertilizer to provide potassium is

KCl

Potash (Potassium Chloride)

KCl 0-0-60

Under the heading for each type of parent material are listed various transporting agents. Select the letter of the answer which correctly indicates the correct set of transporting agents for all parent materials.

Lacustrine: water Aeloian: wind Till: glacier Colluvium: gravity Alluvium: water

Following a bitterly cold winter, you monitor the soil temperature of 3 fields in West Lafayette during the early spring months and graph the following data: Each line represents a different management practice: (1) a bare poorly drained (wet) silt loam, (2) a poorly drained (wet) silt loam with straw mulch and (3) a bare tile drained (dry) silt loam. Of these practices, which line most likely represents the bare tile drained (dry) silt loam?

Line A

Which of these soils most likely has more than 30% organic matter

Loamy, mixed, euic, frigid terric haplofibrists

Of the following, which one primarily determines water movement in saturated soils?

Macropores

The kind of structure common in C horizons where no observable aggregation is present:

Massive

The EPA sets a limit for nitrate in the drinking water due to what adverse health effect?

Methemoglobinemia (blue baby syndrome)

Assuming you have an ideal silt loam, what soil component typically makes up the largest percentage/fraction of the soil?

Mineral

What is an advantage of grid sampling

More details, works with GIS/GPS

Pine seedlings transplanted into the prairie are likely to grow poorly and exhibit P deficiency if _____ are not present or introduced with the seedlings

Mycorrhizal fungi

Given the fertilizer label 9-15-22, which number from this fertilizer label represents P and K and what is the form of each?

N: means 9% of Total N P: means 15% of Available P2O5 K: means 22% Water Soluble K2O

Anhydrous Ammonia

NH3 82-0-0

Ammonium nitrate

NH4NO3 33.5-0-0

Which would be the best form of N fertilizer to apply to an already flooded rice paddy (you want to minimize N loss)

NH4SO4

Which would be the best form of N fertilizer to apply to an already flooded rice paddy (you want to minimize N loss)?

NH4SO4

N-serve, a nitrification inhibitor, is applied to soil to slow down the process of forming

NO2-

Which of these nutrients is most susceptible to leaching when fall applied to a silt loam soil in Indiana?

NO3 -

By definition, a heterotroph has which of the following characteristics:

Needs energy-rich organic substances for "food."

When we were at ACRE, what were we measuring in the water flowing from tile drain?

Nitrogen

What 2 soil horizons are soil organisms most abundant?

O and A

At any given time, most (usually >90%) of the nitrogen in soils is in the form of

Organic matter

We also visited a household which has an above ground septic tank. Explain why the tanks were not built below ground?

Poor drainage

Organic soils (Histosols) like we observed at Celery Bog are often deficient in which of the following nutrients:

Potassium

Use this graph of a plant response to different soil test levels in answering the following: If the soil test value is 30 lb. P/A, which would be more responsive to additional phosphate?

Potato

Phosphorus deficiency

Purple or bronzing on lower leaves, stunted plants

You are sampling soil from Celery bog and notice that the organic material is broken down into a black humic material that is no longer recognizable. This soil would be classified by the comprehensive classification system in the suborder

Saprist

Primary element in the tetrahedral sheet?

Silicon

Which of these soils with a 1% organic matter would be most susceptible to water erosion assuming equal R, LS, C, and P factors?

Silt loam

Which of these textures has the highest water holding capacity?

Silt loam

Which soil texture has the highest water holding capacity?

Silty clay loam

Two soil samples are placed in contact with one another. Soil A has a moisture potential of -15 bar and Soil B has a moisture potential of -0.3 bar. Circle the appropriate answer to make each statement true a) Which soil has the lowest moisture content? b) Water will flow from Soil ______ towards Soil _____

Soil A Soil B to Soil A

On our last field trip, we visited Celery Bog. Give the likely soil order and list 2 potential hazards/issues associated with this soil order

Soil order: histosol Hazards/Issues 1) Subsidence 2) Low potassium

The oldest soils in Indiana are found in which area?

South Central Indiana

Which of these would be the best group of soil acidifiers

Sulfur and FeSO4

Which of these fertilizers is a slow release source of nitrogen

Sulfur coated urea

Combining rock phosphate and H3PO4 makes

TSP

Two Indiana soils, one an alluvium and one a residuum would most likely differ in which soil forming factors?

Time and parent material

________ is the soil forming factor that causes soils to differ within the same catena

Topography

The Frodo silt loam is a fine silty, mixed mesic Typic Fragiudalf. What is the suborder

Udalf

If the base saturation is 20%, what is the soil order?

Ultisol

Which class of land in the Land Capability Class system describes a soil that has severe limitations and would likely only be suitable for recreation, wildlife, or aesthetics is?

VIII

Given the following diagram, what will happen when the wetting front reaches the clay layer? Assume the clay layer is non-expanding.

Water will enter the clay layer at the same rate that it is moving through the upper loam layer above and refrain (cease) from moving beyond the clay until nearly saturated and then will move into the lower loam layer

What is this soil's drainage class?

Well

A soil containing only ferric iron throughout the upper 40 inches of the soil profile would be:

Well drained

A pH meter measures

active acidity which is found on the soil solution

Organic matter has

an amorphous structure with most of its charge from dissociation of carboxylic acid and phenolic groups

In one procedure for determining microbial activity, CO2 - free air is passed over a soil and the CO2 evolved is collected in a solution of Ba(OH)2

as microbial activity increased the BaCO3 (a white precipitate) was formed

The organisms responsible for processes 2 and 3 in the Nitrogen Cycle are

autotrophic

As soils are weathered, they do all of the following except:

become more basic (base saturation increases)

If the hydrogen ion concentration of a soil is 3 x 10-5 M, its pH would be

between 4 and 5.

Heavy vehicle traffic on wet soils may cause soil

bulk density to increase and a platy structure to appear in the A horizon

At ACRE, we examined three different soil pits where the only difference was topography. What word/term do we use to describe this sequence of soils?

catena

A soil which will form a strong ribbon and feels coarse (but less than 50% sand) would most likely be a:

clay loam

Name 2 organisms responsible for non-symbiotic N-fixation

clostridium and azotobacter

Which organisms listed below are non-symbiotic N-fixing organisms

clostridium and azotobacter

On our last field trip, we visited Celery Bog. While standing at the bog, we talked about the golf course and how they were using a particular remediation strategy/technique to minimize the amount of nutrients and pesticides moving into the bog. What method is being used. Be specific.

constructed wetland

Following the tillage of a soil which had not previously been cultivated, the soil organic matter content would

decrease rapidly at first and then stabilize at a new equilibrium

Which are the major mechanisms of soil erosion?

detachment and transport

Time-Domain Reflectometer (TDR) uses an ____________ and records the ____________ of the signal.

electromagnetic pulse; dissipation

What is a disadvantage of grid sampling

expensive

Bioremediation often includes aeration and stirring. This has the effect of

exposing fresh surfaces to activity

Given blocky, granular, massive, and platy, in what order would you expect to find these structures in a well-drained forest soil profile (from top to bottom)?

granular, platy, blocky, massive

A somewhat poorly drained soil is one that

has grey mottles above 18" in a mostly brown background

According to the web soil survey, the soil underlaying Celery Bog is the Houghton series. It is classified as a Euic, mesic Typic Haplosaprist, which means this soil is _______.

highly decomposed, black humic material that is no longer recognizable

Manganese is ____ and symptoms show up in ____ leaves in ____ pH soils

immobile; young; high

The Indiana fertilizer control law protects consumers by

imposing penalties if guaranteed analysis is not met

As % pore space decreases, the bulk density:

increases

As the water content of the soil decreases, the tension with which the remaining water is held by the soil

increases

The tan/brown/red color in a mineral soils is caused by the

iron content

If ammonium nitrate (NH4+ NO3-) was added to soil, then rainwater should

leach the nitrate but not the ammonium

As you move down the soil profile, the subsoils tend to contain _________ macropores than the surface soil layer. _________ total pore space than the surface soil layer __________ organic matter than the surface soil layer

less; more; less

Water moves from ______ tension to ______ tension; ______ potential to ______ potential; ______ free energy to ______ free energy

low; high high; low high; low

Soil O.M (humus) affects the soil by

lowers bulk density, increases CEC, N supply, and H2O storage

Of the following, which one primarily determines water movement in unsaturated soils?

micropores

Microbial release of inorganic plant-available nutrient from organic matter is called

mineralization

Magnesium is ____ and symptoms show up in ____ leaves in ____ pH soils

mobile; old; low

Although we only saw them from a distance, we talked about and observed, the Purdue University Water Quality Field Station. From the soil constituents we have discussed in this class, what specifically could you line these plots with to create a barrier/wall to prevent lateral flow of water so that you could isolate each plot from one another?

montmorillonite

The symbiotic relationship between pine seedling plants and certain fungi growing in and around their roots which increases P uptake is called a

mycorrhizal relationship

Most of nitrogen in soils is in the form of

organic matter

Micronutrients are typically reported in

parts per million (ppm)

Macronutrients are typically reported in

percentage %

Ap Bw Bx Ck

plowed weakly developed fragipan carbonate (salt) accumulation

The weakest step (causes greatest error) in the soil testing procedure is more frequently

sample collection

A soil which forms a strong ribbon and feels gritty (more 50% sand) would likely be a:

sandy clay loam

Given the textural triangle below, what is the soil texture for a soil containing 60% sand, 10% silt, and 30% clay?

sandy clay loam

A soil which will form a strong ribbon and feels smooth would most likely be a

silt loam

Loess is a common parent material for Midwestern soils. The most common surface texture from/of loess is:

silt loam

You measure the diameter of a soil particle and find that it measures 0.03 mm. This particle is most likely a:

silt particle

Bhs Bk Bw

spodosol aridisol inceptisol

The pH of the soil in a buffer solution (SMP) is used to determine

the lime required to change pH

Soil tests should be derived from the soil

the portion of the nutrient closely correlated with that extracted by plants

Predicting the lime requirement of a soil as you did in the Soils Resource Center requires, in addition to the soil pH value

the soil color and texture

Highly weathered soils like ______ are more acidic than younger soils like ____ because some of the basic cations have been leached out of the soil and have been replaced by protons

ultisols, entisols

If your lawn is 100 ft. X 200 ft. and needs 1 lb of N per 500 sq. ft., how much 45-0-0 should be applied?

~89 lbs ((100 x 200)/500) / (0.45) = 89