The Terra Preta method closes the resource loop by linking human sanitation with agriculture.
Terra Preta is based on the lacto-fermentation of organic residue including human waste.
Humans as part of the web of living things can nourish more species than just themselves.
¹ With Fertilizer Prices Skyrocketing, Scientists Scramble to Recover Phosphorus from Waste, Roberta Kwok, February 7, 2013, ScienceNews.org.
² Prehistorically Modified Soils of Central Amazonia: a Model for sustainable Agriculture in the Twenty-first Century, Bruno Glaser, 2006, Institute of Soil Science and Soil Geography, University of Bayreuth.
³ Die Wiederentdeckung der Terra Preta (German, The Rediscovery of the Terra Preta), Film Documentary by Ingo Schulze, 2011, ZDF German Television, featuring Ralf Otterpohl, Jürgen Reckin, Eduardo Goes Neves, Quisibi Kumi, Gilvan Ramos et al.
Terra Preta ‘dark earths’
Food in essence connects the innermost of our body with the cycle of life. It implies that life’s vitality can be passed on from the human organism to other species who make it available to the plants that we eat. Together with the amazing work of critters and microorganisms in place, the substrate of human kidneys can be transformed into fertile soil. In times of rapidly depleting soils, declining — greenhouse gas producing — artificial fertilizer¹, and suffocating oceans, it is evident that contemporary culture is based on a linear, non-cyclic lifestyle.
Discovered from pre-Columbian Maya and Amazonian civilizations, the Terra Preta² method (from Portuguese, ‘dark earths’, referring to the dark coloring of the final substrate) closes the resource loop by integrating human sanitation, biowaste management and agriculture. These ‘dark earths’ contain about three times more Soil Organic Matter than infertile soils and 7000 years ago sustained large populations in central Amazonia. Terra Preta has been recently developed — in part due to new, scientific insights on plant nutrition — as an alternative, ecologically more sensitive approach in dry toilet sanitation³ that is suitable both in urban and rural settings.
Terra Preta is based on the lacto-fermentation of organic residue including human waste and further treatment involving worm-composting. The application of plant-based charcoal and a long timeline ensures that the biowaste is converted to a pathogen-free, safe humus that retains its nutrients. Compared to conventional composting methods, Terra Preta doesn't decompose nutrients but regenerates them. Hence it sequesters carbon-dioxide in the making.
As part of the web of living things we not only need to ask how we feed ourselves but nourish all other species we are intrinsically connected with. Responsibly adapted to contemporary life and with careful risk management in place, the ancient technology Terra Preta lets us experience the ethymological connection between humus and humanity first hand. To this end the main objective of The Nutrient Recovery is to overcome the common mental discomfort of growing food with the addition of human waste products.