The Hillsborough research farm managed by Northern Ireland’s Agri-Food and Biosciences Institute (AFBI) in Co Down will publish live data on its ammonia emissions from this autumn, said Dr Elizabeth Magowan, director of AFBI’s sustainable agri-food sciences division.
Magowan told a visit by the Guild of Agricultural journalists last week that a station installed as part of the deployment of 29 new ammonia sensors across Northern Ireland would start recording minute-by-minute gas concentration and weather information this month. “A web application will be rolled out for anybody to see ammonia emissions from Hillsborough at any time,” she said.
“This scares the life out of me,” she admitted, and researchers will also record farm activities to give farmers and the general public reasons why concentration of the gas varies.
“We will hopefully help farmers and industry to understand when ammonia is at its highest and lowest,” Magowan said. “For example, how much does digestate or slurry spreading impact ammonia emissions, compared to cows being housed in the winter?”
The project aims to “make ammonia visible”, a recommendation of a 2017 expert group, since followed by a Government draft strategy considering restrictions on splash plate slurry spreaders “in preparation for a total ban”.
The AFBI has also been refining the measurement of crude protein impact on ammonia emissions.
Ammonia is harmful to biodiversity and human health, and some of it turns into greenhouse gases when it degrades in the atmosphere
In the Republic, a clean air strategy and a code of practice on ammonia in farming are also under preparation after the country exceeded its EU ceiling for the first time in 2016. In both jurisdictions, over 90% of ammonia emissions come from agriculture and they are on the rise as a result of increasing livestock numbers, with slurry storage and splash-plate spreading the main activities releasing the gas.
Ammonia is harmful to biodiversity and human health, and some of it turns into greenhouse gases when it degrades in the atmosphere.
The AFBI is trialling two technologies to extract solids and nutrients from slurry at Hillsborough: a screw press and a centrifuge.
Researcher Chris Johnston demonstrated the screw press, which processes 10 cubic metres of slurry per hour and separates 10% of its volume into solids containing 25% of the phosphorus – a nutrient associated with widespread water quality issues in Northern Ireland.
The liquid fraction is returned to a slurry tank for spreading on the land, while the solids can be exported.
“To remove that off the farm will reduce the phosphorus pressure of nutrient management on the holding itself,” said Johnston.
He is exploring options for the solids, including use as biomass fuel or gasification, which could replace fossil fuels; and biochar production.
Biochar can help to reduce carbon emissions from soils and agricultural by-products.
The GrassCheck growth monitoring service operated by AFBI and AgriSearch in NI can help farmers prepare for climate change, said Elizabeth Magowan. Decades of data will provide answers to questions such as “how much grass can we expect to grow with how much rainfall”, she said. Researcher Steven Morrison showed new equipment used in Hillsborough to take precision agriculture to grassland, from grass-measuring drones to a mobile feeder measuring each grazing animal’s supplement feed intake and connected fertiliser and slurry spreaders delivering data on the nutrients deposited on each piece of land.