Case Studies

Circular Agronomics > Case Studies


Site description: Mediterranean biogeographic region with mild winters, warm summers and water scarcity due to low precipitation

Challenges: Increased competition for water between different users and conservation of soils that have low organic carbon content.

High farming intensity, livestock concentration in specific areas resulting in high N surplus.

Objective: To close loops within cropland farming – from livestock to cropland farming – and to increase the re-use of manure in a sustainable manner in order to improve soil fertility, increase nutrient use efficiency and reduce emissions.

Selected management practices:

  • Livestock: pig manure valorisation (anaerobic co-digestion of pig manure solid/liquid separation, stripping and solar drying). Production of organic fertilisers)
  • Cropland: long-term organic fertilisation in soils (assessment of changes in soil organic carbon and phosphorus accumulation in soils)
  • Mixed-farming system with ruminants (precision feeding tools) and production of fodder crops

Expected benefits:

  • Reduced nutrient surplus per agricultural area and increased nutrient efficiency on a yield scaled basis
  • Reduced direct emissions to air and water and reduced indirect emissions
  • Increase net stabilisable carbon stocks in cropland.
  • Reduction of carbon-and nutrient-rich waste

Leading partner: IRTA

See the case study leaflet: web version (CAT, EN, ES) / print version (recto: CAT, EN, ES; verso: CAT, EN, ES)

See the case study poster


Site description: sandy soils, 500 mm annual precipitation, 9.6°C mean temperature with long dry summer periods. Crops grown: cereals, oil seedrape, maize, potatoes, fodder crops, grass

Objective: Improving nitrogen efficiency at different stages of crop production

Selected management practices:

  • Testing organic N-fertiliser application strategies for minimising yield-scaled emissions
  • Studying genotypic differences in mechanisms contributing to N-efficiency of plants
  • Management of treated residues application, application strategies and potentials of recovered mineral fertilisers from digestates
  • Experiment with 5 different biogas digestates, applied twice a year since 2011

Expected benefits: Improvements are expected in:

  • Yields of grain and nitrogen content in straw
  • Ammonia and nitrous oxide emissions
  • Nitrate leaching
  • Testing performance of recovered mineral fertilisers in comparison to original materials

Leading partner: IASP

See the case study leaflet: web version (DE, EN) / print version (recto: DE, EN; verso: DE, EN)


Site description: Mountain areas with mean altitude of 1148m, average slopes of 22.7%, low mean annual temperatures of 5.2°C and mean annual precipitation of 720mm

Challenges: Area with low productivity, stocking rates are 1.02 LSU/ha of which 92% are cattle. Farmers aim to differentiate their products in the market to sustain themselves economically. Animals feed mostly on forage and concentrate represents only 5% of their diets. The main challenge is to establish a totally independent and closed system of local production under rough, alpine conditions.

Objective: Close nutrient cycles at dairy farms and reduce GHG emissions which are usually attributed to extensive farming systems

Selected management practices:

  • Close N-P and P-Cycles at dairy farms
  • Feeding strategies, gaseous emissions and manure characteristics (using a respiration chamber). These will be tested on 70 organic farms in the region.

Leading partner: AREC

See the case study leaflet: web version (DE, EN) / print version (recto: DE, EN; verso: DE, EN)


Site description: Emilia-Romagna is one of the major agricultural regions in the North of Italy, characterised by a continental climate (Mediterranean along the Adriatic coast), now influenced by extreme events due to climate change, such as long dry periods and concentrated heavy rains, to be tackled through new agricultural practices. Livestock is concentrated in the western part of the region (Emilia), resulting in high nitrate levels in groundwater, whilst the eastern part (Romagna) with cereals and orchards, has low C content soils. The biogas sector has become important over the past 10 years: to date, almost 200 agricultural biogas plants are working in the region, producing more than 5 million tons of digestate. The Emilia-Romagna case study can be divided into 2 specific sites in Parma and Correggio.

Challenges: Agricultural production in Emilia-Romagna is contributing to a series of environmental impacts including ammonia and GHG emissions, nitrate leaching, reduction of soil organic matter and water shortage.

Objective: Reverse the decrease in soil organic matter and improve the value of digestate as a fertiliser.

Selected management practices:

  • Conservation tillage and cover crops to increase soil organic matter/ recycling nutrients at CIATO FARM
  • Digestate treatment (microfiltration) to be used via a drip-line fertigation system at CAT COOPERATIVE

Expected benefits: Agronomic and environmental benefits are expected from both sites:

  • Conservation tillage: increase in soil organic matter, nutrient recycling, energy and water saving, competition with weeds and biodiversity increase
  • Digestate treatment and application: reduction of ammonia and GHG emissions, mineral fertilisers and water saving and increase in crop yields.

Leading partner: FCSR

See the case study leaflet: web version (EN, IT) / print version (recto: EN, IT; verso: EN, IT)

CASE STUDY 5: Gelderland (Netherlands)

Site description: The Netherlands can be characterised by an Atlantic climate, alluvial soils and shallow groundwater tables. The Gelderland case study is located in the center of the Netherlands, on sandy soils with relatively low organic matter content that is typical for large parts of the Netherlands with intensive livestock farming. The case-study is located on the experimental farm of Wageningen University, where several field experiments are established and will be set up.

Challenges: Decennia of excess fertilisation have resulted in large amounts of “legacy Phosphorus (P)” that cannot be readily accessed by plants but could potentially sustain crop growth for up to 50 years. Furthermore, the intensive agriculture in combination with sandy soils make agricultural systems prone to losses of nitrogen (N) through leaching and emissions of NH3, N2O and NOx.

Objectives: There are two main objectives. The first is to analyse the potential of above- and belowground biodiversity of productive grassland to improve the cycling of Carbon (C), Nitrogen (N) and Phosphorus (P) from biosolids. The second objective is to establish which combinations of grasses, legumes, and earthworms, will best:  mitigate greenhouse gas emissions, increase soil organic carbon and optimise N and P recycling.

Selected management practices: There are two main objectives. The first is to analyse the potential of above- and belowground biodiversity of productive grassland to improve the cycling of Carbon (C), N and P from biosolids. The second objective is to establish which combinations of grasses, legumes, and earthworms, will best:  mitigate greenhouse gas emissions, increase soil organic carbon and optimise N and P recycling.

  • Plant diversity: 5 agriculturally-relevant grass and legume species will be used in monocultures and in combinations to find out which plant community will best used the soil P and mitigate greenhouse gases emissions,
  • Earthworm diversity: common Dutch earthworm communities will be used in combination with different P fertilisers, both conventional and novel, to assess the earthworm effect on P availability for plant growth,
  • Biosolid amendments: both N-related (ammonium sulfate and ammonium bicarbonate) and P-related (NH4-struvite and K-struvite) biosolids will be applied in field experiments to test the fertiliser abilities of those novel product.

Expected benefit: The different field experiments will bring new knowledge on:

  • Which plant traits are important to access less available P in soil
  • Which pant traits can help mitigate greenhouse gases emissions from intensively managed grasslands
  • What are the fertilising properties of novel biosolids and how earthworm communities can modulate those properties

Leading partner: WUR

See the case study leaflet: web version (EN, NL) / print version (recto: EN, NL; verso: EN, NL)


Site description: South Moravia has area 7 065 km2 – 9 % of the area in the Czech Republic and 1 135 586 inhabitants. South Moravian territory has hottest climate in the Czech Republic. 60% of the soil is agricultural land which of is 83 % arable. Soil is very fertile and has to be irrigated at several places to produce agricultural products.

Challenges: Challenges are to considerably reduce high nutrient losses from food-production and food waste and increase recycling to farms.

Objective: Demonstration of C-rich product addition to the soil. Waste products from food industry (esp. dairy industry) will be targeted. Demonstration will be practiced on wheat crops.

Selected management practices:

  • Application of carbon rich compounds to winter wheat fields to increase soil organic carbon
  • Recovery of carbon rich compounds for reuse on farms through the application of electrospun nanofibrous membranes for whey separation

Leading partner: ASIO

See case study leaflet: web version (EN, CZ) / print version (recto: EN, CZ; verso: EN, CZ)