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OKIsItJustMe

(21,734 posts)
2. Terra Preta (AKA “Biochar”)
Mon Oct 19, 2015, 04:43 PM
Oct 2015
https://en.wikipedia.org/wiki/Terra_preta
[font face=Serif][font size=5]Terra preta[/font][HR][font size=1]From Wikipedia, the free encyclopedia[/font]

[font size=3]Terra preta (Portuguese pronunciation: [ˈtɛʁɐ ˈpɾetɐ], locally [ˈtɛhɐ ˈpɾetɐ], literally "black earth" or "black land" in Portuguese) is a type of very dark, fertile manmade (anthropogenic) soil found in the Amazon Basin. Terra preta owes its name to its very high charcoal content, and was made by adding a mixture of charcoal, bone, and manure to the otherwise relatively infertile Amazonian soil. It is very stable and remains in the soil for thousands of years.[1][2] It is also known as "Amazonian dark earth" or "Indian black earth". In Portuguese its full name is terra preta do índio or terra preta de índio ("black earth of the Indian", "Indians' black earth&quot . Terra mulata ("mulatto earth&quot is lighter or brownish in colour.[3]

Terra preta is characterized by the presence of low-temperature charcoal in high concentrations; of high quantities of pottery sherds; of organic matter such as plant residues, animal feces, fish and animal bones and other material; and of nutrients such as nitrogen (N), phosphorus (P), calcium (Ca), zinc (Zn), manganese (Mn).[4] It also shows high levels of microorganic activities and other specific characteristics within its particular ecosystem. It is less prone to nutrient leaching, which is a major problem in most rain forests. Terra preta zones are generally surrounded by terra comum ([ˈtɛhɐ koˈmũ] or [ˈtɛhɐ kuˈmũ]), or "common soil"; these are infertile soils, mainly acrisols,[4] but also ferralsols and arenosols.[5]

Terra preta soils are of pre-Columbian nature and were created by humans between 450 BC and AD 950.[6][7] The soil's depth can reach 2 meters (6.6 ft). Thousands of years after its creation it has been reported to regenerate itself at the rate of 1 centimeter (0.39 in) per year[8] by the local farmers and caboclos in Brazil's Amazonian basin, who seek it for use and for sale as valuable potting soil.

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Recommendations

0 members have recommended this reply (displayed in chronological order):

Yes! appal_jack Oct 2015 #1
Terra Preta (AKA “Biochar”) OKIsItJustMe Oct 2015 #2
might be a good place for this Kali Oct 2015 #3
Latest Discussions»Issue Forums»Environment & Energy»Carbon sequestration in s...»Reply #2