The document discusses the various types of organic and organo-mineral fertilizers available for Mediterranean soils, emphasizing their benefits and limitations. Key topics include nutrient cycling, environmental impact, and the role of organic wastes in improving soil fertility while minimizing nutrient loss and pollution. It also addresses the future perspectives for developing more efficient and sustainable fertilizer practices in agriculture.

1. What new types of organic
fertilisers are available for
Mediterranean soils?
What are the benefits, limitations and
perspectives for new developments?
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Dr. Maria Pilar BERNAL
Research Professor
CEBAS-CSIC. Murcia, Spain.

2. Soil Organic Matter
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Hiederer R. 2013. Mapping Soil Properties for Europe. Spatial
Representation of Soil Database Attributes. European Commission,
Joint Research Centre.

3. Organic fertilisers – 1G
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Animal manures
 Slurry
 Crop residues
 Municipal solid wastes
 Biowastes
 Sewage sludge
 Biosolids
 Agro-food residues
Soil application
• Nutrients and OM used for crop
production.
• Soil fertility maintained.
• Minimum environmental impact.
• Nutrient balance: production/need
Traditional farming

4. Livestock – arable farming split
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Intensive & specialised farming systems
 Economic efficiency.
 Mechanised management.
 Precision agriculture.
 Change: manure to slurry.
 Manure accumulation.
 Excess of nutrients & OM.
 Environmental impact.
 Input of fertilisers &
pesticides.
 Soil fertility in risk (loss
of OM).
 Environmental impact.
Nutrient input Nutrient input
 Scarce water sources.
 Highly valuable crops.
 Intensive production.

5. Organic fertilisers – 2G
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Animal manures
 Slurry
 Crop residues
 Municipal solid wastes
 Biowastes
 Sewage sludge
 Biosolids
 Agro-food residues
Wastes
• Excess: not enough agricultural land.
• Pollutants: HM, pathogens.
• Environmental impact.
• Nutrient loss.
• Food safety.

6. Compost
Dry solids
Organic fertilisers – 2G
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Animal manures
 Slurry
 Crop residues
 Municipal solid wastes
 Biowastes
 Sewage sludge
 Biosolids
 Agro-food residues
Separation
Solid
Liquid Depuration

7. Organic fertilisers – 3G
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Animal manures
 Slurry
 Crop residues
 Municipal solid wastes
 Biowastes
 Sewage sludge
 Biosolids
 Agro-food residues
• Nutrient cycling.
• Energy recovery.
• C-conservation.
• Environment.
Resources

8. Organic fertilisers – 3G
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Animal manures
 Slurry
 Crop residues
 Municipal solid wastes
 Biowastes
 Sewage sludge
 Biosolids
 Agro-food residues
• Drying.
• Pyrolysis.
• Combustion.
• Advanced composting.
• Anaerobic digestion.
Biological
Thermal
Nutrient recovery
Compost
Digestate
Pellets
Biochar
Ash (P / K)
Products
NH4-sol.
Struvite
Phosphates
Concentrates
• Stripping.
• Precipitation.
• Filtration.

9. Organic fertilisers in a Circular Economy
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Solid manure
Slurry
Digestate
(Co)-digestion
Separation
SOLID
FRACTION
LIQUID
FRACTION
Liming Composting
Incineration Drying
Pelleting
P-ashes
Organic
fertiliser
Organic
fertiliser
Effuent =
Irrigation
K-fertiliser
(NH4)2SO4
solution
Ammonia
stripping
Biological
treatment
Liming
Evaporation
Filtration
Constructed
wetlands
CompostOrg. Ca-
fertiliser
Treated waterMineral
concentrates
Processing
Processing
Mg/K
struvite
Bio-based fertilisers
Adapted from: EIP-AGRI Focus Group. How to improve the agronomic use of recycled nutrients (N and P) from livestock manure and other organic sources?
Pyrolysis
Biochar

10. Organic fertilisers
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Microbial stability
 Reduced moisture
 Pathogen and weed destruction
 Nutrient concentration
 Stable OM
 Easy to transport/use
 Quality standards
 Recognised fertiliser/amendment
× Gaseous emissions
× Investment and running costs
× OM mineralisation & N-loss
× Organic / HM contaminants
Compost Dry solids
 Physical stability
 Very low moisture
 Pathogen and weed destruction
 Nutrient concentration
 Easy to transport/use
 High OM
× Microbial instability
× Gaseous emissions
× Investment and running costs
× High energy requirement
× N-loss
× HM contaminants
Nutrient availability?

11. Organic fertilisers
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Microbial stability
 Very low moisture
 Pathogen and weed destruction
 High-C conservation
 Recognised amendment
 Production of energy
 Reduction of GHG from soil
× High investment and running costs
× High N-loss
× Organic contaminants (PAHs)
× Quality criteria not established
Biochar Ash
 Physical stability
 Very low moisture
 Pathogen and weed destruction
 Nutrient concentration
 Easy to transport/use
 Rich in P and K
× Gaseous emissions
× High energy requirement
× Low in N and C
× HM contaminants
Nutrient availability?

12. Organic-C in compost vs. biochar
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Manures
Biowastes
Biosolids
Food ind.
Biochar
TOC (%)
0
20
40
60
80
100
Compost
TOC > 15%
Solid organic fertiliser
EU fertilising
products
TOC > 7.5%
Soil improver
Biochar
Adapted from: Alvarenga et al.,
2019. in: Climate Change and Soil
Interactions,, M.N.V. Prasad (Ed.)
Chapter 5. Elsevier.

13. Nutrients in Compost vs. Biochar
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Manures
Biowastes
Biosolids
Food ind.
Biochar
TN (%)
0
1
2
3
4
5
6
Manures
Biowastes
Biosolids
Food ind.
Biochar
P2O5 (%)
0
1
2
3
4
5
6
7
8
Compost Compost
Solid organic fertiliserEU fertilising products:
TN > 2.5%
P2O5 > 2%
Total > 4%
Struvite, biochar and ash-based products are not included in categories of component materials, but will be further considered.
Adapted from: Alvarenga et al.,
2019. in: Climate Change and Soil
Interactions,, M.N.V. Prasad (Ed.)
Chapter 5. Elsevier.

14. Digestate
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Drymatter,TOC(%)
0
5
10
15
20
TN,P2O5(%)
0
1
2
3
DM TOC TN P
Liquid organic fertiliserEU fertilising products:
TOC > 5%
TN > 2%
P2O5 > 1%
∑ > 3%
Adapted from: Alvarenga et al.,
2019. in: Climate Change and Soil
Interactions,, M.N.V. Prasad (Ed.)
Chapter 5. Elsevier.

15. Organic fertilisers – 4G
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Source materials:
 Organic wastes
 Products from waste treatment;
 Plant / seaweed extracts.
Why?:
 Improve nutrient availability;
 Reduce GHGs;
 Water use efficiency;
 Prevent soil degradation.
Climate Smart Agriculture

16. Recovery of nutrients
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
• P: by precipitation or
struvite formation
• NH3: by stripping
Liquids from
digestate, slurry
• NH3: using gas-
permeable membranes
Animal buildings,
slurry storge tanks,
or composting piles
• P: from manures /
sludges
• K: from plant material
Ash from
combustion
Technology
under
development
Limited
solubility
Quality & P avail.
Concentration

17. Organic fertilisers – 4G
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
• Nutrient enrichment
• Environmental impact
Reduced
emissions
N, P
availability
OM quality
Food safety
• Mineral fertiliser
replacement value
• C-conservation
• Liquid org. fertiliser
Microbial
activation
• Biostimulants
• Nutrient availability
• Limit HM in input
• POPs
• Anti-microbial
resistance

18. Plant Biostimulants
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
 Improve plant characteristics
 Improve soil rhizosphere
• Nutrient use eficiency
• Tolerance to abiotic stress
• Quality traits
• Availability of confined nutrients
in the soil or rhizosphere
Microbial Plant Biostimulants
Azobacter spp.
Mycorrizal fungi
Rhizobium spp.
Azospirillum spp.
Non-Microbial Plant Biostimulants

19. 1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
Source materials
Process developed
Characteristics
evaluated
Quality parameters
Pollutants: HM,
organics
Soil: OM, microbial
activity, etc.
Environmental
implication
Regulation by
legislation
Nutrient efficiency
Biorefinery: Recovery of
nutrients and compounds.
Food safety
Prevention of pollution:
Emerging contaminants
Enhance soil health and
functions
Mitigation of GHGs:
test, evaluation and
implementation.
Cost-benefit
User acceptance
Market development
ChallengesAchievements

20. Future?
1st Summit of the Organic and Organo-Mineral Fertiliser Industry in Europe
pbernal@cebas.csic.es