in amazonia, the provisioning of nutrients from the decomposition of naturally available organic matter fails as the heavy rainfalls wash away the released nutrients and the natural soils (ferralsols, acrisols, lixisols, arenosols, uxisols, etc.) lack the mineral matter to provide those nutrients. the clay matter that exists in those soils is capable of holding only a small fraction of the nutrients made available from decomposition. in the case of terra preta, the only possible nutrient sources are primary and secondary. the following components have been found: human and animal excrements (rich in p and n); kitchen refuse, such as animal bones and tortoise shells (rich in p and ca); ash residue from incomplete combustion (rich in ca, mg, k, p and charcoal); biomass of terrestrial plants (e.g. compost); and biomass of aquatic plants (e.g. algae). saturation in ph and in base is more important than in the surrounding soils. microorganisms and animals the peregrine earthworm pontoscolex corethrurus (oligochaeta: glossoscolecidae) ingests charcoal and mixes it into a finely ground form with the mineral soil. p. corethrurus is widespread in amazonia and notably in clearings after burning processes thanks to its tolerance of a low content of organic matter in the soil. this as an essential element in the generation of terra preta, associated with agronomic knowledge involving layering the charcoal in thin regular layers favorable to its burying by p. corethrurus. some ants are repelled from fresh terra preta; their density is found to be low about 10 days after production compared to that in control soils. modern research on creating terra preta synthetic terra preta a newly coined term is 'synthetic terra preta’. stp is a fertilizer consisting of materials thought to replicate the original materials, including crushed clay, blood and bone meal, manure and biochar is of particulate nature and capable of moving down the soil profile and improving soil fertility and carbon in the current soil peds and aggregates over a viable time frame. such a mixture provides multiple soil improvements reaching at least the quality of terra mulata. blood, bone meal and chicken manure are useful for short term organic manure addition. perhaps the most important and unique part of the improvement of soil fertility is carbon, thought to have been gradually incorporated 4 to 10 thousand years ago. biochar is capable of decreasing soil acidity and if soaked in nutrient rich liquid can slowly release nutrients and provide habitat for microbes in soil due to its high porosity surface area. the goal is an economically viable process that could be included in modern agriculture. average poor tropical soils are easily enrichable to terra preta nova by the addition of charcoal and condensed smoke. terra preta may be an important avenue of future carbon sequestration while reversing the current worldwide decline in soil fertility and associated desertification. whether this is possible on a larger scale has yet to be proven. tree lucerne (tagasaste or cytisus proliferus) is one type of fertilizer tree used to make terra preta. efforts to recreate these soils are underway by companies such as embrapa and other organizations in brazil. synthetic terra preta is produced at the sachamama center for biocultural regeneration in high amazon, peru. this area has many terra preta soil zones, demonstrating that this anthrosol was created not only in the amazon basin, but also at higher elevations. a synthetic terra preta process was developed by alfons-eduard krieger to produce a high humus, nutrient-rich, water-adsorbing soil. terra preta sanitation terra preta sanitation (tps) systems have been studied as an alternative sanitation option by using the effects of lactic-aid conditions in urine-diverting dry toilets and a subsequent treatment by vermicomposting.