SSC LONG QUIZ

Question 1

Properties that are influenced by soil
texture include

Answer 1

PPISW
porosity, permeability, infiltration, shrink-swell rate, water-holding
capacity

Question 2

the only soil in which neither sand, silt nor clay
predominates is called

Answer 2

loam

Question 3

The mineral
constituents of a loam soil

Answer 3

40% sand
40% silt
20% clay

Question 4

Sand is least active, having the least specific surface area, followed by silt; clay is
the most active.

Answer 4

SSC
SAND>SILT>CLAY

Question 5

USDA STANDS FOR?

Answer 5

UNITED STATED DEPARTMENT of AGRICULTURE

Question 6

REVIEW TEXTURAL TRIANGLE

Question 7

The clumping of the soil textural components of sand, silt and clay
causes

Answer 7

AGGREGATE

Question 8

to form and the further association of those aggregates into
larger units creates

Answer 8

SOIL STRUCTURE/PEDS

Question 9

Soil structure affects

Answer 9

AWCPR
aeration, water movement, conduction of heat, plant root
growth and resistance to erosion

Question 10

RESEMBLES COOKIE CRUMBS AND USUALLY LESS THAN 0.5 CM IN DIAMETER. COMMONLY FOUND IN SURFACE HORIZONS WHERE ROOTS HAVE BEEN GROWING

Answer 10

GRANULAR

Question 11

IRREGULAR BLOCKS THAT ARE USUALLY 1.5-5.0 CM IN DIAMETER

Answer 11

BLOCKY

Question 12

VERTICAL COLUMNS OF SOIL THAT MIGHT BE A NUMBER OF CM LONG. USUALLY FOUND IN LOWER HORIZONS

Answer 12

PRISMATIC

Question 13

VERTICAL COLUMNS OF SOIL THAT HAVE A SALT CAP. AT THE TOP. FOUND IN SOILS OF ARID CLIMATE

Answer 13

COLUMNAR

Question 14

THIN, FLAT PLATES OF SOIL THAT LIE HORIZONTALLY. USUALLY FOUND IN COMPACTED SOIL

Answer 14

PLATY

Question 15

SOIL IS BROKEN INTO INDIVIDUAL PARTICLES THAT DO NOT STICK TOGETHER. ALWAYS ACCOMPANIES A LOOSE CONSISTENCE COMMONLY FOUD IN SANDY SOILS

Answer 15

SINGLE GRAINED

Question 16

Peds are flattened one atop the other 1–10 mm thick. Found in the Ahorizon of forest soils and lake sedimentation.

Answer 16

PLATY

Question 17

Prismlike peds are long in the vertical dimension,
10–100 mm wide. Prismatic peds have flat tops, columnar peds have rounded
tops. Tend to form in the B-horizon in high sodium soil where clay has
accumulated.

Answer 17

PRISMATIC and Columnar

Question 18

Blocky peds are imperfect cubes, 5–50 mm, angular
have sharp edges, subangular have rounded edges. Tend to form in the Bhorizon where clay has accumulated and indicate poor water penetration.

Answer 18

Angular and Subangular

Question 19

Spheroid peds of polyhedrons, 1–10 mm, often found in
the A-horizon in the presence of organic material. Crumb peds are more
porous and are considered ideal.

Answer 19

Granular and Crumb

Question 20

: Is a measure of the degree of development or cementation within
the peds that results in their strength and stability.

Answer 20

Grades

Question 21

Weak cementation allows peds to fall apart into the three textural constituents,
sand, silt and clay.

Answer 21

WEAK

Question 22

: Peds are not distinct in undisturbed soil but when removed they break into
aggregates, some broken aggregates and little unaggregated material. This is
considered ideal.

Answer 22

MODERATE

Question 23

PEDS are distinct before removed from the profile and do not break apart easily

Answer 23

STRONG

Question 24

Soil is entirely cemented together in one great mass such as slabs of clay
or no cementation at all such as with sand.

Answer 24

STRUCTURELESS

Question 25

Soil ______ is typically 2.60 to 2.75 grams per cm3 and is usually unchanging for a given soil. ______ with high organic matter content, and is higher for soils with high iron-oxides content.

Answer 25

PARTICLE DENSITY

Question 26

Soil ________ is equal to the dry mass of the soil divided by the volume of the soil; i.e., it includes air space and organic materials of the soil volume. Thereby soil bulk density is always less than soil particle density and is a good indicator of soil compaction.

Answer 26

Bulk Density

Question 27

The soil bulk density of cultivated loam is about

Answer 27

1.1 to 1.4 g/cm3 (for comparison water is 1.0 g/cm3 ).

Question 28

The more _______ the soil is the the greater is the bulk density value and the less _____ it is.

Answer 28

COMPACT and POROUS

Question 29

FORMULA FOR BULK DENSITY IS

Answer 29

BD=Ws/Vt

Question 30

1.0-1.3

Answer 30

Normal Soil

Question 31

>1.3

Answer 31

Compacted Soil, poor soil structure

Question 32

>1.0

Answer 32

Very loose Soil

Question 33

Sandy soils have ____ because the particles tend to lie close

Answer 33

HIGHER BULK DENSITY

Question 34

of soils is the mass (dry weight) per unit volume of soil excluding the pore spaces within that soil volume

Answer 34

PARTICLE DENSITY

Question 35

Particle density (2.65g/cm^3) indicate the

Answer 35

mineral ancestry of soil

Question 36

A higher particle density that (2.70g/cm^3) may mean that the soil could have been derived from?

Answer 36

Heavy minerals like iron bearing minerals

Question 37

A low particle density (less than 2.50 g/cm^3) may indicate that the soil is ?

Answer 37

high in humus

Question 38

The equation for determining soil particle density is?

Answer 38

PD=Ws/Vs

Question 39

the quality or degree of having minute spaces or holes through which liquid or air may pass.

Answer 39

POROSITY

Question 40

is that part of the bulk volume of soil that is not occupied by either mineral or organic matter but is open space occupied by either gases or water. In a productive, medium-textured soil the total pore space is typically about 50% of the soil volume.

Answer 40

PORE SPACE

Question 41

PORE SIZE

Answer 41

CRYPTOPORES>ULTRAMICROSPORES>MICROPORES>MESOPORES>MACROSPORES

Question 42

The higher its bulk density the lower its _____

Answer 42

Porosity

Question 43

SOIL POROSITY FORMULA

Answer 43

%PS = [1-BD/PD] X 100

Question 44

is the ability of soil to stick to itself or to other objects (cohesion and adhesion, respectively) and its ability to resist deformation and rupture.

Answer 44

CONSISTENCY

Question 45

A soil's resistance to fragmentation and crumbling is assessed in the dry state by rubbing the sample. Its resistance to shearing forces is assessed in the moist state by thumb and finger pressure.

Answer 45

CONSISTENCY

Question 46

depends on the ratio of the energy absorbed to that lost. Soil has a temperature range between -20 to 60 °C, with a mean annual temperature from -10 to 26 °C according to biomes.

Answer 46

SOIL TEMPERATURE

Question 47

* Soils can process and hold considerable amount of water. They can take in water, and will keep doing so until they are full, or until the rate at which they can transmit water into and through the pores is exceeded. Some of this water will steadily drain through the soil (via gravity) and end up in the waterways and streams, but much of it will be _______

Answer 47

RETAINED(SOIL WATER RETENTION)

Question 48

The maximum amount of water that a given soil can retain is called

Answer 48

Field Capacity

Question 49

whereas a soil so dry that plants cannot liberate the remaining moisture from the soil particles is said to be at

Answer 49

wilting point

Question 50

The process by which soil absorbs water and water drains downwards is called

Answer 50

Percolation

Question 51

Soil water retention is essential to life. It provides an ongoing supply of water to plants between periods of replenishment

Answer 51

Infiltration

Question 52

SOIL MOISTURE CONTENT( θ) FORMULA

Answer 52

θ%=[(FW-ODW)] X 100

Question 53

VOLUMETRIC MOISTURE CONTENT

Answer 53

Vw/Vt=θ

Question 54

SOIL WATER DEPTH (HW)

Answer 54

Hw = Ov x Ht

Question 55

a measure of the energy state of water in the soil

Answer 55

SOIL MOISTURE TENSION(SMT)

Question 56

Moisture Content when pore spaces are fully-filled up with water

Answer 56

SATURATION(SAT)

Question 57

Moisture content of the previously saturated soil

Answer 57

FIELD CAPACITY

Question 58

The moisture content of turgid plants begin to wilt permanently

Answer 58

PERMANENT WILTING COEFFICIENT(PWC)

Question 59

Air dry moisture content which is highly dependent on the relative humidity of the atmosphere

Answer 59

Hygroscopic coefficient (HC)

Question 60

_________ condition involves putting the moist soil in an oven at 105-110 C for 24 hours

Answer 60

Oven drying (OD)

Question 61

Gravitation Water (GW)

Answer 61

GW = SAT-FC

Question 62

AVAILABLE WATER CONTENT (AWC)

Answer 62

AWC= FC-PWP