Vincent de Leijster

13 General introduction 1 More recently, scholars proposed the ecosystem service cascade as an alternative classification, which more specifically decomposes an ecosystem service in a chain of individual processes (La Notte et al., 2017). To describe this classification, I collated material by various authors (Barrios, 2007; La Notte et al., 2017; Mace et al., 2012; Swift et al., 2004) who propose that a service starts with a biophysical element which is the entity or underlying process that must be present in order for an ecological process to be initiated. The ecological process is the second step in the chain and refers to the specific function that is performed by the biophysical element. This process then results in an ecological output, and once this ecological output is used by humans, it is referred to as a benefit. This classification can help explain how the supply of ecosystem services can be manipulated, which I have visualized in Figure 1-1 for the agroecological context. A management intervention in the agroecological system may trigger the abundance of an ecosystem service provider; for example, the implementation of flower strips on a farm may attract pollinators (Wratten et al., 2012). As a consequence, there would be a higher abundance of pollinators which would provide a higher pollination activity on the flowers in the agroecosystem (Norfolk et al., 2016; Saunders et al., 2013). The ecological outcome would be that more flowers are pollinated, and this would lead to better fruit set (Klein et al., 2003a). This may then influence the yield in the agroecosystem positively, as more fruit would be produced (Veddeler et al., 2008). Figure 1-1. Ecosystem service cascade with an example of an intervention in the agroecological context. Changes in land management may lead to changes in the supply of ecosystem services. The ecosystem service supply can be measured by variables that indicate the quantity (or quality) at which each element in the chain is delivered (Mace et al., 2012). In