Explaining variability in ecological performance of dairy and pig farms in the Netherlands

PhD project by Mark Dolman. In January 2008, the Ministry of Agriculture, Nature and Food quality stated, that in 15 years, the Dutch animal production sector needs to be sustainable. In order to say whether or not the pig and dairy sector produce in a sustainable way, and to evaluate the effect of mitigation options, insight in their economic, environmental and social performance is required.

An agricultural sector can be considered sustainable when it is economically viable, environmental sound and socially accepted. To get insight into the ecological performance of the pig and dairy sector, a life cycle assessment (LCA) can be used. LCA is an internationally accepted tool to assess the environmental impact of an activity throughout its life cycle, as this method focuses on the impact of on-farm and off-farm production processes. LCA, therefore, allows the identification of the main pollution sources in the production chain.

To assess the environmental performance of a sector, generally average sector data are used in an input-output analysis. Such an assessment gives insight into the environmental performance of the sector, but does not show the variability in performance among farms. In order to explain why a sector is (un)sustainable, variability in performance among farms is the basis to identify which farm or management characteristics are responsible for differences among farm, and thus, why one farm is more sustainable than another. To explore variability in ecological performance among agricultural farms, we have to perform an LCA for individual farms. In agricultural LCAs, data availability of individual farms is a problem. The Dutch FADN data, however, offer an opportunity for reliable LCAs of individual farms.

The first objective of this project, therefore, is to quantify the ecological performance of a sector based on a sample of farms that represent the sector (FADN), i.e., a bottom-up LCA approach. This will be illustrated using dairy farms in the Dutch national FADN sample. Quantifying the ecological performance requires insight in all important environmental impacts, such as use of natural resources (including water), climate change, eutrophication and acidification. The second objective is to use this quantification to explore differences in ecological performance among farms in order to deduce sustainable mitigation options and to improve the ecological performance on farms and of the sector. The second objective will be illustrated for the pig production sector.

This main objective can be refined by defining four case studies:

  1. Can we quantify the ecological performance of the dairy sector in the Netherlands, based on a life cycle assessment of a large group of dairy farms?
  2. How do we include the use of freshwater in the life cycle assessment of milk production on Dutch dairy farms?
  3. Which farm or management characteristics explain differences in sustainability performance among pig farms?
  4. How does the use of normative or farm specific excretion factors affect variation in ecological performance of pig farms?