Issue link: https://maltatoday.uberflip.com/i/1483500
12 OPINION The importance of organic fertilisers in an ever-changing circular economy ORGANIC fertilisers may be produced locally, from local waste whose disposal would otherwise represent costs, envi- ronmental pollution and green- house gas emissions. Organic fertilisers thus turn a costly and a harmful material into a resource. Furthermore, the use of organic fertilisers can reduce the costs and dependency of imported chemical fertilisers, whose pro- duction entails a high use of fos- sil energy. At present, due to the conflict in Europe, fossil-based energy is 3-4 times more costly than in the recent past due to the use of energy as a political weapon. Organic fertilisers thus have wider perspectives as they deal with resilience, independence and self-sufficiency of Malta's economy. The use of fertilisers for crop production may be a small part of the economy in Malta, but a switch from chem- ical to organic fertilisers is very relevant to start addressing environmental, climatic and economic considerations on a national scale. Organic fertilisers are made from livestock manure and other organic material, such as plant residues from the pro- cessing of vegetables. Malta is characterised by having a high livestock density, compared to the rest of the EU. In Mal- ta, livestock production repre- sents, according to Eurostat, more than 203kg nitrogen per hectare , and is therefore well above the limit of 170kg nitro- gen in livestock manure per hectare. The 170kg of nitrogen is given by the EU's Nitrates Directive as a safeguard for the quality of drinking water, set to maximally 50mg nitrate per litre. The 203kg of nitrogen per hectare per year is sufficient for economic crop production in many cases, even for grow- ing two crops per year. Malta's Nitrates Action Programme Regulations (S.L.549.66) is for instance recommending cab- bage to be fertilised with 110kg nitrogen per hectare and car- rots with 90kg nitrogen per hectare. Despite this, Malta imports about 586 tonnes of nitrogen per year in chemical fertilisers , equal to about 54kg of nitrogen per hectare of cul- tivated area. In this context, Eurostat has calculated that the annual nutrient balance in Malta is 145kg of nitrogen and 29kg of phosphorus. This bal- ance equates to that part of the fertilisers that is lost in the en- vironment as pollution. To reduce Malta's farming pol- luting potential and to make the situation more sustainable, the solution is to switch to the use of livestock manure as a crop fertiliser rather than dumping valuable livestock manure into the sewer system for treatment. These practices come at a very high cost to the national econ- omy, and which anyway lead to further pollution of air and water. Livestock manure can, according to EU policies alone, be used for one thing, namely as fertiliser for crops. The complex problem out- lined above is the background for the SYNECO project ( h t t p s : / / w w w . s y n e c o m a l t a . com). SYNECO will promote the process to switch to a more effective use of livestock manure as crop fertiliser and reduce chemical fertiliser im- ports. Anaerobic digestion will initially recover energy from the manure. One ton of slur- ry/manure contains the same amount of energy in the form of biogas as about 15-30 litres of oil or diesel. If the biogas is converted to electricity alone, about 40% of the energy is captured as electricity, mean- ing about 60-120kWh per ton of slurry/manure. Additional- ly, the heat production in the process can be used for various purposes. One dairy cow rep- resents an annual production of about 25 tonnes of slurry/ manure, and one slaughtered pig about half a ton of slurry/ manure. A positive side effect of the anaerobic digestion is that the nitrogen and phospho- rus nutrients in the digestate is more plant available than that of the raw manure. After the anaerobic digestion, SYNECO will further process the digestate into fractions that are easily used as crop fer- tilisers. Despite the short dis- tances in Malta, transport is a challenge and it is important that the manure is treated close to where it is generated. Addi- tionally, the resulting organic fertiliser should be spread on the fields by use of convention- al farming machinery without causing odour and other nui- sances for people living within close proximity. SYNECO is a project of the Farmers Central Cooperative Society Ltd (FCCS), the larg- est fruit and vegetable farm- ers' cooperative in Malta. It is a pilot project financed by the European Union (Rural Devel- opment Programme for Malta 2014-2020) to recycle manure nutrients for fertilising. The author is an agronomist with extensive expertise relat- ing to aspects of livestock ma- nure, including policies, fertil- ising, economy, and processing gained via numerous European research, innovation and de- velopment projects. The au- thor developed CropManager (https://www.cropmanager.eu), which is an online software for crop and nutrient management, including manure accounting and nutrient budgeting. The author is involved in the SYN- ECO project to train farmers to switch from chemical fertilisers to local resources of organic fer- tilisers to reduce impacts on the climate, environment and the farm economy. The author is the founder of the Organe Insti- tute ApS, Denmark. Henning Lyngsø Foged maltatoday | SUNDAY • 6 NOVEMBER 2022 Henning Lyngsø Foged is an agronomist and founder of the Organe Institute ApS, Denmark