Ecosystem services and biodiversity are frequently measured by field-scale indicators. Yet, many important agricultural and economic drivers as well as agri-environmental policies operate at larger sales, to which fieldscale indicators first need to be upscaled. Therefore, this perspective is focussed on upscaling approaches from field to farm or to landscape scale. To understand how ecosystem services and biodiversity are affected by farmscale drivers and to inform future decision- and policy-making while exploiting existing data sources, these need to be upscaled and analysed at farm scale. However, how this is done best for different types of indicators for ecosystems services and biodiversity received little attention so far. In this work, we propose and discuss different options for upscaling ecosystem service and biodiversity indicators from field to farm scale. We base our novel conceptual work on a large body of literature and demonstrate that before deciding on an upscaling approach, different aspects of the indicators and the purpose of the assessment need to be considered. Our propositions start at the point where field-scale data is available for aggregation at farm scale. Such an aggregation needs to consider the relationship between ecosystem service supply and the benefit provided, i.e., the supply-benefit relationship, which describes how a change in supply affects the resulting benefit for farmers and/or society. We argue that this relationship can also be conceptualized for biodiversity, with benefit being the value of a field or farm for biodiversity conservation. Because benefit does often not continuously increase with supply, but can exhibit breaking points defined by thresholds in supply, the shape of the supply-benefit relationship varies among different ecosystem services and biodiversity components. For example, for upscaling biodiversity indicators, a conservation value needs to consider that conservation benefit might non-linearly change with supply, i.e., habitat quality and quantity, and becomes marginal below certain thresholds. Only when such potential thresholds are considered, a suitable upscaling approach can be chosen from the approaches that we present in this work. While some indicators can be upscaled using a simple area-weighted total or average, for others, thresholds in supply are of great relevance for determining the best upscaling approach. We conclude that upscaling indicators to the farm scale holds untapped potential to inform agri-environmental assessments and future policies. By presenting and discussing suitable approaches for different types of indicators, we hope to facilitate upscaling as a tool to support agrienvironmental decision-making in the future.
