In many parts of the world, expansion of agricultural land is a key driver of habitat and biodiversity loss. Internationally traded crops, therefore, have ecological impacts beyond the country in which they are consumed. Combining data on trade, land cover and biodiversity, researchers have developed a new way of explicitly linking imports to effects in the areas of production. Applying the method to German imports of soy from Brazil shows that 70% are traceable to municipalities with a high fraction of damaged ecosystems.
The researchers chose to look at the impacts of soybean as it is the world’s fourth most common arable crop and Brazil - as a biodiversity hotspot - is one of the world’s largest producers. There is also good access to soy production data, and they were able to trace most of Germany’s soy imports for the years 2004, 2011 and 2018 to the area where it was grown, with the TRASE (Transparency for Sustainable Economies) database.
They determined soy’s impacts on biodiversity in different municipalities using the biodiversity intactness index1 (BII) of the producing region – a measure of the current and changing state of biodiversity based on abundance of bird, mammal and amphibian species in 10 km square areas. This is a novel use of the index, say the researchers, as it is more often used to indicate the advantages of protected areas and has not yet been applied in an ecological footprint analysis with such high level of spatial detail. The index classifies biodiversity loss, compared to a baseline, within three boundaries: safe, not intact and severely disturbed. According to the planetary boundaries concept2, for example, some sources suggest that up to 20% loss of species abundance is still within a safe range of change. In this study, the researchers categorised an area as ecologically intact where greater than 80% of biodiversity remained, compared to the baseline; not intact where 30-80% remained; and severely disturbed where less than 30% remained. Analysis used baseline data from 1997, 2004 and 2011.
According to TRASE, 1 746 Brazilian municipalities exported soy to Germany between 2004 and 2018. The cumulative loss in biodiversity in exporting municipalities, weighted according to the amount destined for German markets, was used to indicate the contribution of German soy imports to these changes. For imports in 2004, 2011 and 2018, the analysis indicates that 50% can be traced to ecosystems that are not intact and 20% to severely disturbed ecosystems.
Different ways of looking at the data provide other insights. For example, in 2018, the BII in 78 of the production communities was worse compared to 2004 but had improved in 72 others. Positive changes, however, did not significantly alter the magnitude of the overall negative impact, say the researchers. Neither could reforestation efforts at different locations in a municipality fully compensate for negative effects in cultivated areas, so these were not considered.
A trend was noticed between 2004 and 2018, with German and European soy imports reducing overall, and a greater proportion of German imports coming from sources with intact ecosystems. Nevertheless, the researchers note that total soy production in Brazil strongly increased in this period to meet demand from non-EU importers such as China.
The researchers suggest a classification scheme relating products to their BII impacts, whereby imports from high impact areas can be seen as an indicator of deforestation. Supply chain managers or countries could even aim to avoid imports where the score falls below a certain threshold and give preference to producer regions with lower impacts.
Limitations of the method include that TRASE could not provide comprehensive information for all soy imports. For example, in 2004, 38% of imports were not traceable, and 8% in 2018. Additionally, related products using soy, such as meat and biofuels, exported from Brazil, were not considered – possibly leading to an underestimation of the total biodiversity impacts linked to its cultivation for products consumed in Germany. The researchers also say that more detailed information on species abundance would be useful for other studies replicating this method.
- Scholes, R.J. and Biggs, R. (2005) A biodiversity intactness index. Nature 2005, 434: 45–49.
- Mace, G.M., Reyers, B., Alkemade, R., Biggs, R., Chapin III, F.S., Cornell, S.E., Díaz, S., Jennings, S., Leadley, P., Mumby, P.J. and Purvis, A. (2014) Approaches to defining a planetary boundary for biodiversity. Global Environmental Change, 28: 289-297.
Mahlich, L., Jung, C. and Schaldach, R. (2022) The Biodiversity Footprint of German Soy-Imports in Brazil. Sustainability, 14(23): 16272. https://doi.org/10.3390/su142316272
To cite this article/service:
“Science for Environment Policy”: European Commission DG Environment News Alert Service, edited by the Science Communication Unit, The University of the West of England, Bristol.
Notes on content:
The contents and views included in Science for Environment Policy are based on independent, peer reviewed research and do not necessarily reflect the position of the European Commission. Please note that this article is a summary of only one study. Other studies may come to other conclusions.
- Publication date
- 29 March 2023
- Directorate-General for Environment