p.1
Soil Profile Description Format
What is the purpose of a profile description format in soil morphology?
To systematically describe the characteristics of soil layers.
p.1
Morphological Parameters of Soil
What are morphological parameters in soil science?
Characteristics that describe the physical appearance and structure of soil.
p.29
Morphological Parameters of Soil
What is the main focus of the Morphological Parameters in Soil Science?
To describe the physical characteristics of soil.
p.12
Mottling Patterns in Soil
What are mottles in soil?
Spots or blotches of different color or shades interspersed with the dominant color.
p.46
Morphological Parameters of Soil
What is the main focus of the Soil Test Kit (STK)?
To assess various soil parameters.
p.44
Morphological Parameters of Soil
What is the reaction of soil with HCl indicative of?
It indicates the presence of carbonates in the soil.
p.43
Morphological Parameters of Soil
What are concretions in soil science?
Hard, compact masses of matter formed by the precipitation of mineral cement within the spaces between particles.
p.19
Morphological Parameters of Soil
In which regions do prismlike soil aggregates commonly occur?
In subsoil horizons of arid and semi-arid regions.
What is the definition of platy soil structure?
Aggregates or groups arranged in relatively thin horizontal plates, leaflets, or lenses.
p.13
Mottling Patterns in Soil
What are mottling patterns used for in soil science?
They are chief criteria for placing soils in drainage classes.
p.36
Morphological Parameters of Soil
What are the morphological parameters related to soil?
Characteristics that describe the physical structure and form of soil.
p.29
Morphological Parameters of Soil
Who is the source of the information on Morphological Parameters?
The Soil Survey Division Staff (1993).
p.40
Morphological Parameters of Soil
What is the significance of pH in soil?
It is an important morphological parameter affecting soil properties.
p.37
Morphological Parameters of Soil
What types of roots are found inside peds?
Common very fine roots and many medium roots between peds.
p.32
Soil Consistence Evaluation
What operations are performed during the evaluation of rupture resistance?
Operations required to rupture the soil specimen.
p.26
Morphological Parameters of Soil
What size particles are included in the Coarse Fragments class?
Gravel and cobbles up to 25 cm in diameter.
p.8
Soil Color and Its Significance
What is the dominant spectral color represented by?
The letter abbreviation of the color preceded by numbers from 0 to 10.
p.31
Soil Consistence Evaluation
How is plasticity defined in soil?
An estimate of the soil material's ability to deform without rupturing.
p.32
Soil Consistence Evaluation
How is rupture resistance evaluated?
By removing a block of soil from the horizon and estimating its moisture content.
p.13
Mottling Patterns in Soil
What are the classes of abundance for mottling patterns?
Few (< 2%), Common (2 - 20%), Many (> 20%).
p.36
Morphological Parameters of Soil
What is the significance of studying morphological parameters in soil science?
It helps in understanding soil behavior, fertility, and its interaction with plant roots.
p.15
Mottling Patterns in Soil
What does 'few fine distinct strong brown' (7.5YR 5/6) mottle signify?
It signifies a specific type of mottle in soil description.
p.9
Soil Color and Its Significance
What does the scale from 0 to 10 represent in terms of color?
The darkness or lightness of color based on the amount of light reflected to the eye.
p.6
Soil Color and Its Significance
What does the color white in soil indicate?
The predominance of silica (quartz) or the presence of salts.
p.30
Soil Consistence Evaluation
At how many moisture levels is soil consistence determined?
Three different moisture levels: moist, dry, and wet.
p.28
Soil Texture and Its Classes
What is the definition of Clay (C) textural class?
40% clay and more, less than 45% sand, and less than 40% silt.
p.33
Soil Consistence Evaluation
What does cementation in soil consistence refer to?
A brittle hard consistence caused by cementing substances other than clay minerals, such as CaCO3, Si, or oxides of iron and aluminum.
p.19
Morphological Parameters of Soil
What is the defining characteristic of prismlike soil?
Vertically-oriented aggregates or pillars that vary in length and may reach a diameter of 6 or more inches.
p.34
Soil Consistence Evaluation
How is stickiness evaluated in soil?
By wetting a handful of soil and squeezing and mixing it while adding water and drier soil.
p.7
Soil Color and Its Significance
What was the purpose of the Munsell System of Color Notation?
To provide a color order system before quantitative means of measuring color were developed.
p.32
Soil Consistence Evaluation
What is the first step in evaluating rupture resistance?
Removing a block of soil from the horizon.
p.38
Morphological Parameters of Soil
What is a vugh?
Unconnected voids with irregular shape and walls, often found in fine-textured soils.
p.4
Morphological Parameters of Soil
What are the soil properties evaluated in the field for profile description?
Color, Roots, Mottles, Pores, Structure, Texture, Consistence, Horizon boundary, and other features.
p.3
Soil Profile Description Format
What is the color description of Horizon A in the soil profile?
Light gray (10 YR 7/2) dry.
p.5
Soil Color and Its Significance
What is said about the age of red soils?
They are said to be older.
p.9
Soil Color and Its Significance
What does a rating of 0 on the scale indicate?
Light is completely absorbed, making the material appear black.
p.4
Morphological Parameters of Soil
What does the term 'soil structure' refer to?
The arrangement of soil particles and the spaces between them.
p.41
Morphological Parameters of Soil
What are Soluans?
Cutans consisting of coatings of soluble salts such as carbonates, chlorides, and sulfates.
p.39
Horizon Boundaries and Distinctness
What characterizes a 'Wavy' topography?
Boundary undulates with vertical distance.
p.21
Morphological Parameters of Soil
What are spheroidal aggregates?
Aggregates not over ½ inch in diameter, characteristic of many surface soils, especially those high in organic matter.
p.31
Soil Consistence Evaluation
What is stickiness in terms of soil characteristics?
The tendency of wet soil material to adhere to other objects.
p.43
Morphological Parameters of Soil
What is an example of a type of concretion?
Calcium carbonate concretions.
p.15
Mottling Patterns in Soil
How are mottle colors described?
In the same way as colors of any horizon.
p.10
Soil Color and Its Significance
What does the gradation of purity of color in soil refer to?
The intensity or brightness of a color and the amount of dilution with white light.
What effect do tillage operations have on soil structure?
They tend to destroy structure.
p.20
Morphological Parameters of Soil
What factors influence the development of blocklike aggregates?
Soil drainage, aeration, and root penetration.
p.5
Soil Color and Its Significance
How is soil color determined?
Indicated by common names and Munsell notation.
p.41
Morphological Parameters of Soil
What are Organs?
Cutans of organic matter that usually do not effervesce upon application of 30% H2O2.
p.4
Morphological Parameters of Soil
What does soil consistence refer to?
The resistance of soil to deformation or rupture.
p.14
Morphological Parameters of Soil
What characterizes 'Prominent' contrast in soil mottles?
Mottles are very obvious.
What does soil pH measure?
The acidity or alkalinity of the soil, expressed as H+ ion concentration.
p.42
Soil Color and Its Significance
What is the typical coating that results in a white color in soils?
Sodium salts, carbonates, and silt-sized or smaller quartz grains.
p.39
Horizon Boundaries and Distinctness
What does an 'Irregular' topography indicate?
Boundary undulates lateral distance.
p.39
Horizon Boundaries and Distinctness
How is the distinctness of the horizon boundary determined?
By how accurately the investigator feels the depth of the boundary can be identified.
p.2
Soil Profile Description Format
What does the second column represent in the Profile Description Format?
Depth of the upper and lower boundaries of a horizon (in centimeters).
p.33
Soil Consistence Evaluation
How is soil consistence evaluated?
The specimen must be air dried and then submerged in water for at least one hour.
What characterizes a massive soil structure?
The entire soil horizon appears cemented in one great mass.
How is soil salinity conventionally measured?
By the electrical conductivity of a saturation extract.
p.43
Morphological Parameters of Soil
What are Fe-Mn concretions?
Concretions that contain iron (Fe) and manganese (Mn).
p.15
Mottling Patterns in Soil
What are the most common mottle colors?
Yellowish-brown, dark reddish-brown, and gray.
p.38
Morphological Parameters of Soil
What causes packing voids?
Formed between larger particles that do not adequately pack together due to their size and shape.
p.11
Soil Color and Its Significance
What does the value in Munsell notation indicate?
70% of incident light is reflected.
What is the benefit of promoting soil aggregation and aggregate stability?
It enhances soil structure.
p.42
Soil Color and Its Significance
What causes light gray soil color?
Reduced iron (Fe2+) and salts.
p.42
Soil Color and Its Significance
Which compound is responsible for bright orange colors in soils?
Lepidocrocite [-FeO(OH)].
p.12
Mottling Patterns in Soil
What causes mottling in soil?
Alternating periods of reduction and oxidation due to seasonally fluctuating water tables.
p.43
Morphological Parameters of Soil
Where are concretions typically found?
In sedimentary rock or soil.
p.32
Soil Consistence Evaluation
What does rupture resistance evaluate in soil?
The strength of soil to withstand an applied stress.
What is a single-grain soil structure?
Where individual soil particles show no tendency to cling together, such as pure sand.
p.37
Morphological Parameters of Soil
What does the presence of many very fine and common fine roots imply about their distribution?
That roots are uniformly distributed since location is not specified.
What are the two types of structureless soil?
Single Grain and Massive.
p.25
Soil Texture and Its Classes
How does soil texture influence the ease of working the soil?
It affects the ease with which soil can be worked.
p.25
Soil Texture and Its Classes
What impact does soil texture have on air and water retention?
It influences the amount of air and water the soil will hold.
p.14
Morphological Parameters of Soil
What are the size classes of individual mottles in soil?
Fine (<5 mm), Medium (5-15 mm), Coarse (>15 mm).
p.3
Soil Profile Description Format
What is the pH level of Horizon A?
Strongly acidic (pH 5.3).
p.3
Soil Profile Description Format
What additional features are noted in Horizon A?
Few fine black and dark brown concretions.
p.31
Soil Consistence Evaluation
What does rupture resistance evaluate in soil?
The strength of soil to withstand an applied stress.
What is soil salinity?
The amount of soluble salts in a soil.
p.40
Morphological Parameters of Soil
What are concretions in soil?
Additional features that can be observed in soil morphology.
p.13
Mottling Patterns in Soil
What does 'abundance' refer to in the context of mottle patterns?
The percent of exposed surface area occupied by mottles.
p.36
Plant Roots and Soil Pores
How do soil pores affect plant growth?
Soil pores allow for air and water movement, which are essential for root respiration and nutrient absorption.
p.15
Mottling Patterns in Soil
What does a common medium distinct yellowish brown mottle (10YR 5/6) indicate?
It indicates a specific mottle description in soil.
p.38
Morphological Parameters of Soil
What defines a vesicle?
Unconnected voids with smooth walls and usually rounded shapes.
p.41
Morphological Parameters of Soil
What causes the modification of texture, structure, or fabric at natural surfaces in soil materials?
Concentration of a particular soil constituent.
p.5
Soil Color and Its Significance
What range of colors does soil color fall within?
The range of red and yellow of the spectral color.
p.30
Soil Consistence Evaluation
Why is soil water content critical in assessing soil consistence?
It influences the properties of rupture resistance, stickiness, and plasticity.
p.14
Morphological Parameters of Soil
What is indicated by 'Distinct' contrast in soil?
Mottles readily seen; differ by 1 or 2 hues or several chroma units.
p.28
Soil Texture and Its Classes
What characterizes a Loam (L) textural class?
Less than 52% sand, 7 - 27% clay, and 28 – 50% silt.
What is a structureless soil structure?
No observable aggregation or definite orderly arrangement of natural lines of weakness.
p.40
Morphological Parameters of Soil
What are ped coatings?
Additional features found in soil morphology.
p.13
Mottling Patterns in Soil
What are the four parameters used to describe mottle patterns in soils?
Abundance, size, contrast, and color.
p.36
Plant Roots and Soil Pores
What is the role of plant roots in soil?
Plant roots help anchor the plant and can influence soil structure and nutrient uptake.
p.38
Morphological Parameters of Soil
What are pores in soil?
Voids in the soil filled with soil solution or soil atmosphere.
p.40
Morphological Parameters of Soil
What role do carbonates play in soil morphology?
They are an additional feature that can be present in soil.
p.20
Morphological Parameters of Soil
What are blocklike aggregates in soil?
Original aggregates reduced to blocks, ranging from a fraction of an inch to 3 or 4 inches in thickness.
p.15
Mottling Patterns in Soil
What does 'many coarse prominent yellowish brown' (10YR 5/6 to 5/8) mottle indicate?
It indicates a prominent mottle presence in soil.
p.9
Soil Color and Its Significance
What does a rating of 10 on the scale indicate?
Complete reflection of light, making the material appear absolute white.
p.6
Soil Color and Its Significance
What does the color red in soil indicate?
The accumulation of iron oxide.
p.30
Soil Consistence Evaluation
What does soil consistence refer to?
The way a soil 'feels', including its resistance to rupture, penetration, plasticity, toughness, and stickiness.
p.4
Morphological Parameters of Soil
What is meant by soil texture?
The size and distribution of soil particles (sand, silt, clay).
p.14
Morphological Parameters of Soil
What are the classes of contrast in soil mottles?
Faint, Distinct, Prominent.
p.39
Horizon Boundaries and Distinctness
What does a 'Smooth' topography indicate?
Plane boundary with few irregularities.
p.34
Soil Consistence Evaluation
What is stickiness in soil?
The tendency of wet soil material to adhere to other objects.
p.37
Morphological Parameters of Soil
What is the order of root description in soil analysis?
Quantity, Size, and Location.
p.19
Morphological Parameters of Soil
What are the two types of prismlike soil aggregates?
Columnar (rounded tops) and Prismatic (flat tops, flat sides).
What does soil structure describe?
The clustering of soil particles into aggregates of certain size, shape, and stability.
p.40
Morphological Parameters of Soil
How does salinity affect soil morphology?
It is an additional feature that can influence soil characteristics.
p.35
Soil Consistence Evaluation
How is plasticity evaluated in soil?
By molding a handful of soil after removing particles greater than 2 mm and alternately wetting and adding dry soil.
p.35
Soil Consistence Evaluation
What is the goal of molding soil to evaluate plasticity?
To obtain maximum plasticity and form a 'roll or wire' 4 cm long.
p.25
Soil Texture and Its Classes
How does soil texture affect water movement?
It affects the rates at which water can enter and move through the soil.
p.38
Morphological Parameters of Soil
What are planes voids?
Elongated voids along one plane or axis, commonly formed at ped faces.
p.20
Morphological Parameters of Soil
What is the characteristic of blocky aggregates?
Edges of the cubes are sharp and the rectangular faces distinct.
p.11
Soil Color and Its Significance
What are the components of the Munsell color notation example 5YR 7/2?
Hue – 5YR, Value – 7, Chroma – 2.
p.4
Horizon Boundaries and Distinctness
What is a horizon boundary in soil?
The transition between different soil layers or horizons.
p.39
Horizon Boundaries and Distinctness
What does a 'Broken' topography signify?
Horizon is discontinuous.
p.21
Morphological Parameters of Soil
What is the significance of spheroidal aggregates in soil management?
They are the only types of aggregation commonly influenced by practical methods of soil management.
p.29
Morphological Parameters of Soil
Which division is associated with the study of Morphological Parameters?
Division of Soil Science, ASI, CAFS, UPLB.
p.5
Soil Color and Its Significance
What does soil color reflect?
Specific characteristics of the soil.
How can soil structure development affect air-water relations?
It can modify the effect of texture on air-water relations.
p.6
Soil Color and Its Significance
Which colors are most influential in well-drained soil?
White, red, brown, and black.
p.35
Soil Consistence Evaluation
What characteristic must the 4 cm 'roll or wire' of soil have?
It must be able to support its own weight when held on end.
p.25
Soil Texture and Its Classes
What aspect of plant growth is influenced by soil texture?
The ease of root penetration and expansion.
p.6
Soil Color and Its Significance
What do brown and black colors in soil indicate?
The level and type of organic matter.
p.14
Morphological Parameters of Soil
What characterizes the 'Coarse' size class of mottles?
Diameter greater than 15 mm.
p.14
Morphological Parameters of Soil
What does 'Faint' contrast indicate?
Mottles and matrix are very similar in hue and chroma.
What is the term for blocklike soil structure?
Blocky or Subangular Blocky.
What are some common soluble salts found in soils?
Calcium, magnesium, sodium, chloride, sulfate, and bicarbonate.
p.26
Morphological Parameters of Soil
What are the two classes of soil according to morphological parameters?
Fine Earth and Coarse Fragments.
p.25
Soil Texture and Its Classes
What does soil texture refer to?
The relative proportion of soil separates (sand, silt, and clay) in a given soil.
p.10
Soil Color and Its Significance
What does a gradation value of 0 indicate?
Absolute achromatic colors (pure grays, white, and black) with no hue.
p.41
Morphological Parameters of Soil
What are cutans in soil science?
Broad group of pedological features, including 'clay skins', associated with surfaces of skeleton grains, peds, and voids within soil materials.
p.11
Soil Color and Its Significance
What does chroma in Munsell notation signify?
90% dilution of pure hue with white light.
p.4
Morphological Parameters of Soil
What are some other features that can be evaluated in soil profile description?
Concretions, clay skins, pH, salinity, etc.
p.34
Soil Consistence Evaluation
What is the goal of evaluating stickiness in soil?
To determine when the greatest degree of stickiness is achieved.
p.37
Morphological Parameters of Soil
Where are common very fine and common fine roots concentrated according to the example?
Along vertical faces or peds.
p.35
Soil Consistence Evaluation
What does plasticity in soil refer to?
The ability of soil materials to deform without rupturing.
p.11
Soil Color and Its Significance
What does the hue in Munsell notation represent?
Wavelength 1/4 way between pure red and pure yellow.
What materials can help build up soil structure?
Addition and decomposition of organic matter, lime, and binding agents like Fe/Al oxides, clays, and silica.
p.3
Soil Profile Description Format
What is the structure of Horizon A?
Very weak, fine granular structure.
p.26
Morphological Parameters of Soil
Are stones and boulders considered part of the soil?
No, they are not considered part of the soil.
p.20
Morphological Parameters of Soil
What happens to the edges in subangular blocky aggregates?
Subrounding has occurred.
p.14
Morphological Parameters of Soil
What does 'Contrast' refer to in soil mottles?
The relative difference between the color of the mottles and matrix color.
p.28
Soil Texture and Its Classes
What is the purpose of defining textural groups in soil science?
To categorize soil based on particle size distributions with similar behavior and management needs.
p.4
Morphological Parameters of Soil
What are mottles in soil?
Irregular spots or blotches of different colors in the soil.
p.41
Morphological Parameters of Soil
What are Mangans?
Dark brown or black cutans that are opaque in thin sections and effervesce upon application of 30% H2O2, indicating presence of manganese oxides.
p.30
Soil Consistence Evaluation
What are the key parameters evaluated in soil consistence?
Rupture resistance, stickiness, and plasticity of hand specimens.
p.39
Horizon Boundaries and Distinctness
What are the categories of distinctness in horizon boundaries?
Very Abrupt, Abrupt, Clear, Gradual, Diffuse.
p.42
Soil Color and Its Significance
What causes the black or bluish-black color in soils?
Reduced manganese (Mn2+).
p.39
Horizon Boundaries and Distinctness
What are the types of topography for horizon boundaries?
Smooth, Wavy, Irregular, Broken.
p.42
Soil Color and Its Significance
What minerals contribute to reds, browns, and oranges in soil color?
Iron minerals or amorphous iron compounds.
p.42
Soil Color and Its Significance
What compound is linked to reddish-brown soil color?
Ferrihydrite [Fe2^3+O3・0.5(H2O)].
