Vincent de Leijster

37 Agroecological management improves ecosystem services in almond orchards within one year 3 Table 3-2. The selectedecosystemservices for this study, corresponding indicators, units ofmeasurement, sample size and month of data collection. Ecosystem service indicator Unit No. of farms samples/ plot Date of data collection Nutrient cycling Enzymatic activity Dehydrogenase μ g INTF g -1 h -1 5 3 April 2017 Glucosidase μ g PNG g -1 h -1 5 3 April 2017 Phosphatase mg PHP g -1 h -1 5 3 April 2017 Urease mg NH 4+ g -1 h -1 5 3 April 2017 Soil nutrient availability Total soil N content % 5 3 Aug–Sept 2017 Soil extractable P content ppm 5 3 Aug–Sept 2017 Soil extractable K content ppm 5 3 Aug–Sept 2017 Leaf nutrient status Leaf N content mg g -1 6 3 Aug–Sept 2017 Leaf P content ppm 6 3 Aug–Sept 2017 Leaf K content ppm 6 3 Aug–Sept 2017 Carbon stock Soil organic carbon content tC ha -1 5 3 Aug–Sept 2017 Understory carbon content tC ha -1 6 6 April–May 2017 Habitat provisioning Arthropod abundance # of individuals 6 4 April–May 2017 Arthropod species richness # of orders 6 4 April–May 2017 Understory cover % 6 6 April–May 2017 Understory plant species richness # of species 6 6 April–May 2017 Food provisioning Almond yield kg tree -1 5 4 Aug–Sept 2017 Kernel weight g kernel -1 4 4 Aug–Sept 2017 Pest control Pest abundance # of individuals 6 4 April–May 2017 Natural enemy abundance # of individuals 6 4 April–May 2017 Enemy:Pest ratio ratio 6 4 April–May 2017 Pollination Pollinator abundance # of individuals 6 5 March 2017 Fruit set Fruit:Flower ratio 6 4 March–May 2017 Enzymatic activity Soil enzymatic activity, which relates to soil microbial activity and nutrient cycling processes (Sinsabaugh et al., 2008), has proven to be a powerful tool for assessing soil quality, as enzymes respond rapidly to changes in soil management (Burns et al., 2002). For this study we chose the enzymes β-glucosidase, phosphatase, urease and dehydrogenase, because