This webinar will be comprised of two presentations: Exploring variations in demand for fertilisers derived from recycling in NW Europe by Romke Postma and Imke Harms, Wageningen University and Research; and New developments in the production of plant-available phosphorus from abattoir waste by Martin Blackwell and Tegan Darch, North Wyke, Rothamsted Research, UK.
Exploring variations in demand for fertilisers derived from recycling in NW Europe
Romke Postma and Imke Harms, Wageningen University and Research
The nutrients N, P and K are often applied to agricultural fields as mineral fertilisers. Currently, fertiliser production in the EU depends on imported raw materials (P, K) and energy (N). Each year about 2,392 Gg of P is imported into the EU-27, mostly in the form of mined rock phosphate or as animal feed. Within the scope of sustainable agriculture and a circular, bio based economy, it is crucial to find ways to reduce quantities of non-recycled nutrients and to decrease the dependency on nutrient imports.
Within north west Europe (NWE), regional differences can be identified with respect to nutrient supply and demand. Hot-spots with a surplus of P in animal manure in the NWE territory are the Netherlands, Flanders in Belgium and Brittany in France. At the same time, there are regions with potential to replace mineral P fertilisers: areas with the highest levels of usage are Northern France, Wallonia in Belgium, Eastern England and Ireland. Within the scope of the NWE Interreg project ReNu2Farm, the opportunities for the replacement of nutrients from traditional mineral fertilisers by recycled nutrients from regions with a nutrient surplus is explored. Recycling-derived fertilisers (RDF’s) could be made from animal manure, food waste, sewage sludge, etc. The objective of this paper is to quantify the requirement of N, P and K in various regions within the NWE territory and to formulate the desired properties of the RDF’s, from an agronomic perspective.
In a desk study we quantified the demand for nutrients and organic matter in regions within NW Europe. This demand is quantified at the basis of the area of crops grown per region, the yield levels, the fertiliser recommendations, the soil types (clay, silt, loam, sand), the soil quality (bioavailability of the nutrients in the soil), the current legislation and the common fertiliser practice.
In addition, the regional availability of nutrients in animal manure and other organic fertilisers is affecting the fertiliser choice and the additional demand for recycled nutrients in each region. For this reason, the current use of animal manure per region is also quantified.
From these two factors, the net potential demand for nutrients in RDF’s is quantified. In broad terms, the regional differences in potential demand for nutrients in RDF’s could be characterised by the main crops, soil types and quality and the availability of animal manure in that region. Regional variations in demand for external inputs of organic matter are also considered.
There will be a written paper accompanying this webinar.
New developments in the production of plant-available phosphorus from abattoir waste
Martin Blackwell and Tegan Darch, North Wyke, Rothamsted Research, UK
Our long-term food security depends on finding a sustainable alternative to the finite and unevenly distributed rock phosphate deposits that are used to make the vast majority of our phosphorus fertilisers, on which global food production relies. More urgently, there is a need to reduce the quantities of phosphate that are released into the environment and which are reported to have exceeded the limits of sustainability. Furthermore, over 2 billion people worldwide are currently affected by micronutrient deficiencies, and crop concentrations of essential minerals are declining. There is unlikely to be a single solution to these issues at a global scale, and so a range of solutions are required.
This paper examines whether a novel, recycled, multi-element fertiliser can contribute towards solving these problems by producing crop yields comparable to conventional rock phosphate derived fertilisers, and have an additional benefit of increasing essential mineral concentrations. This fertiliser is produced from abattoir and recycled industrial by-products, and as part of its novel production process, it increases the quantity of human edible protein recovered from a single animal by around 15%, compared to typical carcass processing.
It was tested against conventional mineral fertilisers in a pot trial with wheat and grass. In soil, yields were comparable between the fertiliser types, but, in a low nutrient substrate, it showed a yield benefit. Elemental concentrations in the plant material typically reflected the relative concentrations in the fertiliser, and plants fertilised by it contained significantly more of some essential elements, such as selenium and zinc. Furthermore, concentrations of the toxic element cadmium were significantly lower in crops fertilised by this new fertiliser. Among the fertilisers, manganese concentrations were greatest in the new recycled fertiliser, but within the fertilised plants, they were greatest under the mineral fertiliser, showing the complexity of assessing whether nutrients will be taken up by crops.
In summary, fertilisers from livestock waste have the potential to improve wheat and grass concentrations of essential elements while maintaining yields. Their ability to make a significant impact on the fertiliser market is frequently questioned, but if all global beef cattle by-products were processed in this way, it is estimated that 50 million tons per annum of fertiliser could be produced, representing ca. 20% of the current global fertiliser use.
There will be a written paper accompanying this webinar.