The 45th year of cultivation for the Sludge Trials on Arable land in Scania
Just over half of Sweden's sewage sludge is spread on arable land. Yesterday, the management group for the Sludge Trials on Arable Land in Scania had a meeting at VA SYD's headquarters.
Recently the Swedish National Association of Farmers issued a recommendation to use Revaq-certified sludge if farmers are interested in spreading sludge on their arable land.
VA SYD’s current priority is to spread its sludge on arable land and then only Revaq-certified sludge. VA SYD is investigating sludge pyrolysis because the municipal association often has problems spreading sludge from Ellinge Wastewater Treatment Plant (WWTP) due to high Cd/P mass ratios in the sludge, but also to be equipped with knowledge for upcoming tougher quality requirements for the sludge.
This year marks the beginning of the 45th year of cultivation for the Sludge Trials on Arable Land in Scania. The trial plan includes nine combinations of sludge input and mineral fertiliser rates at two trial sites; Igelösa outside Lund which receives sludge from Källby WWTP and Petersborg outside Malmö which receives sludge from Sjölunda WWTP.
Sludge input has resulted in increased yields and has given higher humus content and increased levels of plant-available phosphorus. Plant uptake of the heavy metals lead, cadmium, chromium, mercury, nickel and zinc does not differ between sludge-fertilised and non-sludge-fertilised trial sites. A summary article about the trials can be found here and analytical data from the basic trials can be found here.
Yesterday’s half-day management group meeting was devoted to discussions about the basic trials and about previous and proposals for future in-depth studies.
The management group for the trials includes Ulrika Dyrlund Martinsson Rural Economy and Agricultural Society Scania, David Gustavsson VA SYD, Ann Thorén SYSAV, Anders Finnson Swedish Water and Wastewater Association, Gunnel Hansson Rural Economy and Agricultural Society Scania and Kjerstin Ekvall SYSAV. Agneta Thor Leander at VA SYD is also part of the management group, but was unfortunately ill yesterday.
Ulrika Dyrlund Martinsson Rural Economy and Agricultural Society Scania, David Gustavsson VA SYD, Ann Thorén SYSAV, Anders Finnson Swedish Water and Wastewater Association, Gunnel Hansson Rural Economy and Agricultural Society Scania and Kjerstin Ekvall SYSAV.
If you would like to read more about various in-depth studies that the experiments have participated in, you will find links to them below:
Plant nutrients and soil properties
Biology
Sjögren et al. (1996), Johansson & Torstensson (1998), Malmström (2020) & Juhanson et al. (2021)
Organic micropollutants
Hörsing et al. (2014), Österås et al. (2015), Hörsing & Ledin (2016), Magner et al. (2016), Hörsing et al. (2018) & Kärrman et al. (2024)
Microplastics
Antibiotic resistance
Rutgersson et al. (2020a), Rutgersson et al. (2020b)