Life Cycle Assessment

Table of Contents

1. Introduction
   1. Objectives
   2. Learning goals
   3. Teacher page
2. Course content: Life cycle assessment (LCA) of pork chains
   1. What are the environmental impact of food production?
   2. Global warming
   3. GWP of different foods
   4. Nutrient enrichment (eutrophication)
   5. Acidification
3. How to access environmental impact of pork?
   1. LCA of 1 kg Danish Pork
   2. What is included in a LCA?
   3. Phase 1
   4. Phase 2
   5. Phase 3
   6. Phase 4
   7. System expansion and allocation
4. LCA for different production Systems
   1. The Danish standard system
   2. The Danish organic system
   3. The French standard system
   4. The Alternative French system: Porc Basque
   5. Summary of performance and LCA in the four systems
5. Completion
   1. Comments
   2. Self-assessment
   3. Key messages
   4. Further reading and references
   5. Evaluation
   6. Acknowledgement

Nutrient enrichment (eutrophication)

Another environmental consequence of food production is eutrophication. Ecosystems are affected by substances, which contains nitrogen or phosphorus (e.g. manure/slurry, fertilizer). The consequences of nutrient enrichment are increased biomass production (organic matter) and decreased biodiversity, which arises from increased growth of the relatively few species, which are able to utilize the increased amount of nutrients. Examples can be algae bloom in aquatic ecosystems at the expense of those species flourishing in a relatively nutrient poor environment. A considerable algae growth leads to disappearance of higher plants, and the decomposition of dead algae create a lack of oxygen, which can affect the amount of the more oxygen demanding aquatic animals.

In the same way as GWP is calculated in CO₂-eq., the eutrophication potential is calculated in NO₃-equivalents (see Table 3).

Table 3. Equivalent factors for GWP and eutrophication

GWP equivalent factors:
1 kg carbon dioxide (CO2)	1 kg CO2-eq.
1 kg methane (CH4)	25 kg CO2-eq.
1 kg laughing gas (N2O)	298 kg CO2-eq.
Eutrophication equivalent factors:
1 kg nitrate (NO3)	1 kg NO3-eq.
1 kg ammonia (NH3)	3.64 kg NO3-eq.
1 kg phosphate (PO43-)	10.45 kg NO3-eq.

Figure 5. Algae bloom (aquatic ecosystem) and decreased biodiversity
(terrestrial ecosystem) as a consequence of eutrophication