The german study "Sichtbarmachung versteckter Umweltkosten der Landwirtschaft am Beispiel von Milchproduktionssystemen" [Making hidden environmental costs of agriculture visible using the example of milk production systems] investigated the individual sub-processes involved in milk production for different, typical regions of milk production in Germany. The study differentiated between conventional and organic production as well as farm models with and without pasture management, and calculated the environmental costs of each production system.
The results show:
- Milk production systems with pasture management are better for the environment than production without pasture management (stables).
- The milk produced at organic farms is virtually always more environmentally friendly than milk produced by the conventional competition.
- Organic farm models with pasture management have the lowest environmental impact whereas conventional farms without pasture management generate the highest environmental costs.
The study points to the significant role of feed production on environmental impact: in conventional milk production, feed provision accounts for 18 to 34 percent of greenhouse gas emissions from milk and is thus the main driver of climate change impact. The figure for organic production is only 6 to 20 percent, i.e. one to two thirds less. In terms of direct emissions from milk production (digestion), on the other hand, organically produced milk does not fare as well. This is because the individual cow gives less milk than the same cow in conventional farming models. As a result, the proportion of emissions from digestion per kilogram of milk is higher.
Environmental costs are costs that are borne by society. These costs include those incurred to the healthcare system as a result of disease caused by emissions, or costs for the restoration of impaired ecosystems.
The average climate cost of 18 euro cents accounts for the largest share of environmental costs. However, those costs are actually likely to be even higher because it is not yet possible to monetise the costs of all types of environmental damage, e.g. biodiversity losses.
The study looked at the environmental impacts of greenhouse gas emissions, water consumption, pollution of water and soil with nitrates or phosphorus (eutrophication, acidification), exposure of humans and the environment to chemicals (toxicity) and farm-internal energy use. Farms with pasture grazing perform better in all categories compared to farms without. When comparing organic and conventional farms, organic farms have an environmental advantage in all categories except for land use and acidification as a result of their manure application. The reason for this exception is the lower yields associated with organic farming and the larger area required for feed production
The Öko-Institut Institute for Applied Ecology, INFRAS and KTBL carried out the study on behalf of the German Environment Agency.