“The work I have been developing in my PhD has the aim of producing a bio-based fertilizer with known ratios of N-P-K, through the blending of raw or treated manures. In this specific case, the reuse of organic materials will contribute to a circular economy through the nutrients’ incorporation from manures.
This is an important step to reduce the use of synthetic fertilizers, not only to reduce the carbon footprint of the manufactory of synthetic nitrogen, but also, to have a natural and renewable source of phosphorous, since the needed to produce mineral fertilizers is from a phosphate rock which is a non-renewable resource, and the restitution of soil organic matter through organic materials is, also, important to restore soil’s health.
On a first step I pre-selected the manures and the treatments (fraction separation, acidification, and fraction separation after acidification) within the Portuguese reality. So far, an exhaustive analysis of all products obtained have been made in term of all nutrients. In order to assess the potential of nitrogen mineralization a small trial was conducted to evaluate if the materials obtained are from quick or slow release (an abstract concerning this trial will be presented in ManuREsource). Also, some experiments are been conducted to assess if phosphorous availability to the crops. This extensive characterization will help to prepare the blending, in order to know what can be expect when reusing the nutrients, and to select the materials that will be used to produce the bio-base fertilizer”.