Vincent de Leijster

9 General introduction 1 1.1 Agricultural management and its impact Optimizing the profitability of food production has been a highly active field of research for centuries. The Green Revolution, an agricultural intensification approach promoting chemical inputs and specialization on single crops, started in the second half of the 20th century and resulted in an enormous increase in agricultural efficiency. It has been estimated that global agricultural productivity has increased by 126% over the last century, of which 30–50% was driven by chemical fertilization (Erisman et al., 2008). This intensification has resulted in better accessibility to food worldwide as well as decreasing poverty and hunger, especially in developing countries (Pingali, 2012). Moreover, it has also affected the economics and profitability of farms. For example, in Europe the work load on farms decreased by 3% between 1995 and 2000 (Baum et al., 2006) while the farmers’ net income improved (Dawson et al., 2016). Both trends have contributed to improved livelihoods, making the Green Revolution a success from a humanitarian perspective (Burney et al., 2010). Nevertheless, the fast growing number of studies on this topic demonstrate that agricultural intensification and the associated conventional agriculture also lead to environmental trade-offs which are expected to influence the—up until now—positive economic impact of the intensification approach. For example, a global meta-analysis synthesized 115 studies on agricultural land intensification and found that intensification increased yields by 20%, but that it also led to an average species loss of 9% (vertebrates, invertebrates, and plants), and in some cases even up to 22% (Beckmann et al., 2019). Conventional agriculture is responsible for 14% of the total greenhouse gas emissions, and land management practices related to conventional agriculture (e.g. intensive tillage and bare soils) also reduce soil organic carbon stocks, with estimated reduction rates of 55-66% in carbon sink capacity in agricultural soils (Lal, 2004). Moreover, conventional agriculture is a major cause of phosphorus and nitrogen pollution, both types surpassing the critical values of the planetary boundaries (Rockström et al., 2009). Finally, it has been estimated that agriculture currently consumes 92% of the ground and surface waters worldwide (Hoekstra et al., 2012). In sum, the current conventional management in agriculture generates many environmental trade-offs; as a result, alternative agricultural management strategies with smaller environmental footprints are increasingly being experimented with. If we are to achieve sustainable agricultural production, we need to look for land management approaches that not only provide food production, while maintaining or improving ecological functionality and biodiversity, but that also deliver these services in a balanced and resilient way. Such alternative environmentally-friendly land management