1 / 9

Soil Color & Its Causes

Soil Color & Its Causes. Factors that give soil color. Organic matter Weathered mineral material composing the soil Quantity and condition of iron present. Dark Color in the A Horizon. Usually indicates the presence of organic matter This is a characteristic of the A horizon.

harva
Download Presentation

Soil Color & Its Causes

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Soil Color & Its Causes

  2. Factors that give soil color • Organic matter • Weathered mineral material composing the soil • Quantity and condition of iron present

  3. Dark Color in the A Horizon • Usually indicates the presence of organic matter • This is a characteristic of the A horizon

  4. Sub-soil Color Determination • Quantity and condition of iron • Red colors = usually associated with unhydrated iron oxides and indicate a well drained soil • Yellow colors = largely due to hydrated iron oxides and generally indicate a somewhat more moist condition than red colors

  5. Basic Color Classifications • Light • Medium • Dark

  6. Color Determination in the field • ALWAYS USE MOIST SOIL • Munsell’s color charts • Absolute black = 0 • Absolute white = 10 • Light soils hue value = 7 or more • Medium soils hue value = 5 – 6 • Dark soils hue value = 4 or less

  7. Munsell Color Charts Hue = dominant spectral or “rainbow” color • Red, Yellow, Blue, Green Value = relative blackness or whiteness • Reflected light Chroma = purity of “color” • Number increases and the color is more brilliant as grayness decreases

  8. Change in soil color… • Indicates a difference in the soil’s mineral origin (parent material) • Or change in soil development

  9. Mottles • Spots of different colors in the soil • Generally indicate that the soil has periods of inadequate aeration each year • Usually rust colored • Bluish, grayish, & greenish subsoils (gleying) – with or w/o mottles = indicate longer periods each year of waterlogged conditions & inadequate aeration.

More Related