- (Science of Vedic scriptures)
- What s soil?
- Functions of soil
- Important/significant foundation soil physical properties
- Color – not an influence, but an indicator and diagnostic resource
- Texture – the composition (sand, silt, clay), the feel, the classification (triangle) – micro pores
- Structure – how the particles are aggregated, bound together – macro pores
- Consistence – how the soil holds together, feels, can be worked when wet; assessing texture
- Coarse fragments – rocks don’t hold water!
- Soil reaction – acid or base, leached or not leached, saturated or not saturated
- Soil Nutrients
Standardizing Color – the Munsell Color Chart
- Munsell Color System
- Hue refers to the dominant wavelength of light (color) (red, yellow, green, etc.).
- Value refers to the lightness and darkness of a color in relation to a neutral gray scale.
- Chroma is the relative purity or strength of the Hue.
- Drainage and Wetness
- Soil Color
- Causes of Soil Color
- Humus content
- Iron compounds in the soil
- Basic Soil Color Indications
- Indicator of different soil types
- Indicator of certain physical and chemical characteristics
- Due to humus content and chemical nature of the iron componds
- Color reflects physical, chemical and/or biological composition and processes
- Dark brown-black = organic matter
- Bright-light = leached or bleached zones
- Subsoil color reflects parent material
- Subsoil color reflects redox status
oxidation = aerated
reduction = anaerobic, lacking oxygen
Carbonates, sulfates, chlorides affect color
Mottles, speckles, blotches – alternating wet and dry conditions.
- Soil color as a diagnostic tool
Color reflects the parent material, the soil formation process, and the hydraulic properties of the soil
- There are two ways to ‘look at’ soil color –
- 1) as a diagnostic tool – what happened!
- 2) as a characterization/classification tool – what will happen!
- Redox – reduction-oxidation status
- Reduction – oxygen is depleted from the soil, the soil may be anaerobic, iron and manganese chemistry change, resulting in color changes.
- Oxidation – oxygen is present in the soil, the soil is aerobic, leaching is likely occurring, light color of soil.