Petrogypsic horizon

{
  "id": "MLC-T-ENV-020788",
  "term": "Petrogypsic horizon",
  "field": "Environment",
  "term_source": "Petrogypsic Horizon",
  "definition": "The petrogypsic horizon is an illuvial horizon, 10 cm or more thick, in which secondary gypsum has accumulated to the extent that the horizon is cemented or indurated. Dry fragments do not slake in water, and roots cannot enter, except in vertical fractures that have a horizontal spacing of 10 cm or more. The minimum gypsum content is 5 percent, and the product of the thickness, in cm, multiplied by the gypsum content percentage is 150 or more. Commonly, the gypsum content is far greater than the minimum requirements.",
  "subject": "Natural environments",
  "references": [
    "USDA Natural Resources Conservation Service Soil Taxonomy: A Basic System of Soil Classification for Making and Interpreting Soil Surveys (1999)"
  ],
  "url": "https://mlchart.com/terminology/environment/petrogypsic-horizon/"
}