International trade companies have a huge influence over how land use changes. For example, when important ecosystems like rainforests (the Amazon), savannahs (the Cerrado) and wetlands (the Pantanal) in Brazil are converted into cultivated land for soy crops. We have always known this.

But how exactly does the supply chain work when it comes to soy? Soy is the most traded agricultural product in the world and is used as food and bio-fuel. In my case study, I am examining the entire supply chain network in Brazil. This involves more than 450 communities, numerous lobbyists, farmers, logistics companies, brokers, and more than 1,800 trading companies that sell soybeans primarily to China, and on the European market. I hope to disentangle this complex network and understand the social relationships on which the trade relationships are based. For this reason, I talk to all the stakeholders.

My goal is to understand the risks and the potential in these relationships. With the help of mathematical network analysis, I am also developing a method to measure network relationships and quantify the resulting relationship patterns. If you look at the supply chain of different companies, it is clear that they source their goods in different ways.

Cargill, for instance, an international trading company based in the USA, is reasonably steady in its sourcing activities compared to other, smaller dealers. This means that Cargill has regularly bought a specific amount of soy beans from more or less the same region and the same agricultural operations in Brazil for decades. We call this behaviour 'stickiness'. Whereas other companies consistently buy from different sources and thus fail to build stable trading relationships. The question, then, is whether 'stickiness' and a reliable customer relationship would contribute to more sustainable practices or not. And what would the opposite mean, 'non-stickiness', in relation to sustainability? What side-effects, or spill-over effects, appear when companies move from place to place, or establish structures in one location? My hypothesis is that it is not enough for companies to ensure the sustainability of their supply chains through voluntary commitments.

We cannot leave it to the companies themselves to deal with problems such as species extinction and the climate crisis. What we need are political decisions and strong public authorities that determine what companies are allowed to do and what they are not allowed to do with regard to the way they source goods. An example of this is the European Union's effort to regulate the import of so-called Forest Risk Commodities, of which soy is one. In other words: the EU is developing regulations to prevent what we eat in Europe from continuing to destroy natural habitats around the world.