Vincent de Leijster

46 Chapter 3 Table 3-3. Summary of the GLMMs on the effect of treatments on ecosystem service indicators. Table includes the mean and standard deviation (SD) per treatment, P-value and, if significant, Tukey post-hoc test grouping letters. CT = conventional tillage, NT = no tillage, GM = green manure and CM = compost. Ecosystem service indicator Unit GLMM p -value CT NT GM CM Nutrient cycling Dehydrogenase μg INTF g -1 h -1 0.6 2.1 ± 1.4 2.7 ± 1.9 2.4 ± 1.9 2.7 ± 1.5 Glucosidase μ g PNG g -1 h -1 < 0.001 140 ± 78 b 365 ± 215 a 272 ± 97 ab 333 ± 136 a Phosphatase mg PHP g -1 h -1 < 0.001 102 ± 72.3 b 156 ± 58.6 a 150 ± 59.1 a 159 ± 66.9 a Urease mg NH 4+ g -1 h -1 0.007 33 ± 32 b 65 ± 50 a 51 ± 30 b 55 ± 35 ab Total soil N content % < 0.001 0.09 ± 0.04 b 0.08 ± 0.03 b 0.09 ± 0.04 b 0.11 ± 0.04 a Soil extractable P content ppm 0.006 13 ± 7.9 8.3 ± 6.5 15 ± 8.9 21 ± 15 Soil extractable K content ppm < 0.001 140 ± 94 b 150 ± 120 b 140 ± 98 b 230 ± 140 a Leaf N mg g -1 0.07 1.6 ± 0.26 1.58 ± 0.18 1.73 ± 022 1.75 ± 0.22 Leaf P ppm < 0.001 1.1 x 10 3 ± 1.6 x 10 3 b 1.1 x 10 3 ± 1.4 x 10 2 b 1.1 x 10 3 ± 1.7 x 10 3 b 1.2 x 10 3 ± 2.0 x 10 3 a Leaf K ppm < 0.001 5.5 x 10 3 ± 2.1 x 10 3 b 5.9 x 10 3 ± 1.3 x 10 3 b 4.7 x 10 3 ± 2.3 x 10 3 b 7.7 x 10 3 ± 2.0 x 10 3 a Carbon stock SOC tC ha -1 < 0.001 8.4 ± 5.1 ab 6.4 ± 3.7 b 8.2 ± 9.4 b 9.4 ± 4.0 a Understory carbon stock tC ha -1 < 0.001 0.19 ± 0.34 c 0.44 ± 0.47 ab 0.54 ± 0.35 a 0.41 ± 0.58 bc Habitat provisioning Arthropod abundance # individuals trap -1 0.042 18 ± 18 ab 14 ± 18 ab 12 ± 12 b 25 ± 28 a Arthropod richness # orders trap -1 0.87 3.5 ± 2.2 3.2 ± 1.4 3.2 ± 1.5 3.6 ± 1.8 Understory cover % < 0.001 16.8 ± 23.2 c 56.2 ± 16.7 a 62.6 ± 12.0 a 36.5 ± 33.5 b Understory plant richness # species transect -1 < 0.001 4.8 ± 5.3 c 11.6 ±3.0 a 8.1 ± 3.4 b 7.4 ± 6.0 b Food provisioning Almond yield kg tree -1 0.39 0.54 ± 0.47 0.37 ± 0.24 0.59 ± 0.59 0.48 ± 0.24 Kernel weight g kernel -1 < 0.001 1.08 ± 0.12 ab 1.02 ± 0.15 b 1.06 ± 0.35 b 1.24 ± 0.05 a