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Table 3 Site level bivariate regressions

From: A multi-level analysis of the relationship between environmental factors and questing Ixodes ricinus dynamics in Belgium

Variables Descriptive Statistics Coefficient (Std. Error) in Regressions
Mean Range Site mean nymph abundance Site mean adult abundance
Landscape composition variables
Proportion of broad-leaved forest (%) ra = 500 m 24.98 0–94.95 2.84 (0.99)** 1.67 (0.82)*
r = 1000 m 21.66 0.88–80.30 4.14 (1.13)*** 2.75 (0.93)**
r = 1500 m 21.27 1.06–85.32 4.61 (1.14)*** 3.62 (0.91)***
Proportion of coniferous forest (%) r = 500 m 2.13 0–29.18 5.89 (5.01) 3.67 (4.03)
r = 1000 m 3.92 0–86.68 1.13 (1.97) 0.63 (1.60)
r = 1500 m 2.50 0–25.16 14.61 (5.52)** 10.25 (4.42)*
Proportion of crops and pastures (%) r = 500 m 35.25 0–89.34 −0.37 (1.00) −0.10 (0.82)
r = 1000 m 35.72 0.11–77.07 −0.31 (1.25) −0.03 (1.02)
r = 1500 m 40.10 6.70–83.70 −0.61 (1.36) −0.90 (1.10)
Proportion of heathland (%) r = 500 m 0.11 0–1.11 1.78 (102.86) −16.94 (84.09)
r = 1000 m 0.14 0–1.19 −31.32 (109.82) −23.92 (89.91)
r = 1500 m 0.34 0–11.28 −34.64 (16.62)* −18.81 (14.88)
Landscape (forest) configuration variables
The number of forest patches r = 500 m 11.16 0–27.00 −0.03 (0.04) 0.002 (0.03)
r = 1000 m 51.47 6.00–104.00 0.001 (0.01) 0.005 (0.008)
r = 1500 m 124.90 12.00–240.00 0.001 (0.004) 0.002 (0.003)
Forest edge density (m/ha) r = 500 m 21.56 0–76.97 0.03 (0.01)* 0.02 (0.01).
r = 1000 m 9.83 0–48.32 0.06 (0.02)*** 0.06 (0.01)***
r = 1500 m 14.12 0–47.72 0.07 (0.02)*** 0.06 (0.01)***
Area-weighted mean forest shape index r = 500 m 2.06 0–3.5 0.33 (0.37) 0.42 (0.30)
r = 1000 m 2.67 1.02–4.25 0.66 (0.26)* 0.79 (0.20)***
r = 1500 m 3.01 1.05–5.13 0.72 (0.19)*** 0.80 (0.14)***
Area-weighted mean forest patch fractal dimension r = 500 m 1.11 0–1.22 0.01 (1.50) 0.49 (1.24)
r = 1000 m 1.15 1.02–1.23 10.47 (4.32)* 13.13 (3.45)***
r = 1500 m 1.16 1.03–1.24 11.94 (3.77)** 14.71 (2.99)***
Euclidean mean nearest-neighbour distance between forest patches (m) r = 500 m 102.99 0–589.62 −0.02 (0.01)** −0.005 (0.003).
r = 1000 m 89.03 63.88–339.93 −0.04 (0.01)** −0.08 (0.04)*
r = 1500 m 88.64 63.81–195.46 −0.04 (0.01)*** −0.03 (0.01)***
Aggregation index of forest patches r = 500 m 63.13 0–94.25 0.02 (0.01) 0.01 (0.01)
r = 1000 m 59.42 23.94–89.51 0.04 (0.01)** 0.04 (0.01)***
r = 1500 m 57.67 24.22–90.23 0.04 (0.01)*** 0.05 (0.01)***
Soil variables
Drainage degree 2.98 0–6 −0.17 (0.17) 0.06 (0.14)
Proportion of gravel (%) 3.92 0–20.00 −1.51 (3.08) −1.40 (2.52)
Proportion of sand (%) 37.35 0–90.00 1.01 (0.72) 0.74 (0.59)
Proportion of slit (%) 41.92 0–85.00 −0.25 (0.86) −0.14 (0.70)
Proportion of clay (%) 10.92 0–50.00 −5.12 (2.45)* −3.18 (2.05)
Wildlife variables
Categories of shot roe deer number per 1 km² forest 1.98 1.00–5.00 −0.31 (0.18). −0.20 (0.15)
Number of shot roe deer per 1 km² forest 12.09 0–47.29 −0.02 (0.01) −0.01(0.01)
  1. Significant variables are highlighted in bold.
  2. a r : Buffer zone radius.
  3. ***P < 0.001; **P < 0.01; *P < 0.05; .P < 0.1.