A Combination of Biochar–Mineral Complexes and Compost Improves Soil Bacterial Processes, Soil Quality, and Plant Properties ENG
1Centre for Marine Bio-Innovation & School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
2School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
3School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW, Australia
http://journal.frontiersin.org/article/10.3389/fmicb.2016.00372/fullConquistadors, cannibals and climate change A brief history of biochar ENG
...Unravelling the mystery
Years passed and nothing happened. The Amazon River basin was disregarded as a
site of little wealth or interest. And then, something mundane but brilliant occurred. In
1870, James Orton, a little-known American geologist and explorer, noticed that
alongside the typically grey, acidic soils of the basin there existed large patches of
‘black and very fertile’ soil. Though most would deem this remark insignificant, it is
what soil scientist’s dream of.
Researchers flocked to investigate the mysterious dark earth, or ‘terra preta’ as it is
known locally.
In 1879, naturalist Herbert H. Smith’s concluded that ‘the bluff-land owes its richness to
the refuge of a thousand kitchens for maybe a thousand years’. This finding, reinforced
by geologist William Katzer’s early twentieth century analysis of the soil composition - a
blend of mineral residuum, charred plant materials and decomposed organics - started
turning heads. Was this earth modified by human settlers? Had Orellana been telling
the truth?...
...A closer look at soil science
The rediscovery of this lost civilization is fascinating. Perhaps more surprisingly, so is
terra preta itself:
even chemical fertilizers cannot maintain crop yields into a third
consecutive growing season, yet these dark earths have retained their fertility for
centuries. A crop planted on terra preta can produce a yield up to four times greater
than one planted on soil from similar parent material.
Furthermore, as first reported by Wim Sombroek in 1966, the earth seems to increase
in biomass. Local farmers who mine the soil commercially claim that, as long as a
patch of 20 square centimetres is left undisturbed, it can double in size within about 20
years. It is suspected that this phenomenon is caused by a combination of bacterial
and fungal activity, though as yet no firm conclusion has been reached. So what is the
secret behind the soil’s unusually high
fertility?
The key ingredient, it appears, is carbon. Terra preta soils contain up to 9 per cent
carbon, compared with 0.5 per cent in surrounding soils. This is the cause of the
earth’s dark black colouring....
http://www.pronatura.org/wp-content/uploads/2013/02/History-of-biochar.pdf
Tema: Terra preta i biochar (Pročitano: 71397 puta)
