4. The creation of Terra Preta Nova
In Amazonia, anthropogenic soils with high fertility (Terra Preta, Terra Mulata) are of widespread occurrence. These soils are partly used for agricultural purposes. The use of these soils is subject to competing claims as they are partly used for agricultural purposes but they are also part of the archaeological heritage of the countries. It may, therefore, be important to create and speed up the rate of creation of similar soils, inspired by our knowledge of Terra Preta. This project aims to (1) classify input sources (char quality) and evaluate the char products obtained by different processes for their physico-chemical properties and biological effects; (2) evaluate the most promising products (in combination with mineral fertilizers) in terms of nutrient balances and crop productivity; (3) estimate rates of new formation; (4) look at options and constraints from the biophysical and socio-economic side. Together with project #5 the project will assess potential trade offs between increased agricultural sustainability and productivity and carbon sequestration, and link these data in a decision model that could affect policy makers and institutional discourses when scaling up local Terra Preta Nova projects. Together with project #5 it provides a framework for further questions such as: To whom would benefits (agricultural production, carbon sequestration) accrue? Who would decide about quantities and rates of charcoal addition to such soils? Who decides in cases here is a trade off between soils as carbon sinks and Terra Preta Nova soils as sources for sustainable agriculture?