Vincent de Leijster

66 Chapter 4 was done for the standard deviations of the measured yields. We assumed, based on communications with almond farmers, that almond trees got productive starting from year 5, were on full production in year 9 until year 25, after which they were gradually getting less productive (Appendix Table A4-4.). The assumed income from subsidies for organic almond production was based on the surveys and did not differ between treatments (average of €229.50 ha -1 , n=7). Market price was assumed to be €6.50 per kg organic shelled almond, which was what farmers in this region received in 2018 (pers. comm. Frank Ohlenschlaeger, employee almond trader ‘Almendrehesa’; Llonja de Reus, 2019), and a standard deviation of 20% (or €1.30) was assumed based on the fluctuations in almond market price in Spain between 2012-2018 (FAOSTAT, 2019). Costs: The assumed values for operational costs and investment costs were based on the survey results (Section 4.2.2). Table 4-2 provides an overview of the indicators, the number of responders that contributed to the data and the average costs per hectare. We assumed the most frequently applied cropping density of 156 almond trees per hectare, which corresponds to a planting distance of 8 by 8 m. The surveyed farmers did not applied book-keeping of their land costs, depreciation costs and indirect costs (e.g. taxes, insurances, social security), therefore these costs were taken from a report based on financial surveys undertaken by the Spanish Ministry of Agriculture, Fisheries and Food in 2015 (MAPA, 2018). These financial surveys were conducted in the autonomous community of Murcia, which is directly bordering eastern Andalusia, where our study is conducted. The almond sector of Murcia is comparable to that of Andalusia as most of the almonds of both provinces are produced on the high plains, with comparable biophysical conditions and similar current and historic land management activities. Moreover, the operational costs found in this study are in the order of magnitude as found in other Spanish almond studies (García et al., 2004; MAPA, 2018), and were validated with a local extension service company (‘Crisara’, Chirivel, Spain). The costs of each of the activities in operational costs include resources, labor and diesel (diesel not for pruning and pest control). Tillage costs were multiplied by 3 for CT, by 0 for NT, by 2 for GM and by 3 for CM, to represent the frequency of tillage per year. Diesel costs (€1.00/L) were allocated to tasks that used machinery based on time that machinery was used, resulting in total €120.90 for CT, €92.25 for NT, €106.91 for GM and €134.89 for CM, which are included in the operational costs. Labor costs varied between treatments according to labor hours per management activity and its relative price per hour, as labor for some activities was more expensive (€30 h-1 for harrowing tractor driver and €50 h-1 for harvesting tractor driver) than for others (€15 -1 for pruning and €9 for pest control, seeding