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Table 3 Significant model parameter results for M. maximus, L. leucocephala, and U. virgata probability of occurrence (ѱ) derived from cross-transect surveys conducted along the 570-m bulldozed trail in the Ensenada section of Guánica Forest

From: Spread of common native and invasive grasses and ruderal trees following anthropogenic disturbances in a tropical dry forest

Models β x parameter Megathyrsus maximus Leucaena leucocephala Uniola virgata
ѱ (Dist_z) β 1 (Dist_z) −1.09 ± 0.28*** −1.12 ± 0.26*** 2.21 ± 0.41***
ѱ (Time) β 1 (Dist_z) −1.18 ± 0.30*** −1.28 ± 0.29*** 4.12 ± 0.93***
β 2 (Jul-2012) −2.63 ± 0.60*** −2.42 ± 0.56*** −6.32 ± 1.41***
β 3 (Dec-2012) 1.62 ± 0.69* 2.13 ± 0.67** 5.58 ± 1.41***
β 4 (Jul-2013) 1.77 ± 0.69* 1.83 ± 0.66** 5.95 ± 1.48***
ѱ (NatVeg) β 1 (Dist_z) −1.33 ± 0.33*** −1.39 ± 0.31*** 4.11 ± 0.92***
β 2 (Jul-2012) 0.59 ± 1.61 0.15 ± 1.57 −5.20 ± 14.98
β 3 (Dec-2012) 1.53 ± 0.71* 2.07 ± 0.68** 5.58 ± 1.42***
β 4 (Jul-2013) 1.81 ± 0.71* 1.87 ± 0.68** 5.95 ± 1.48***
β 5 (natural regeneration) −3.33 ± 1.59* −2.66 ± 1.54 −1.12 ± 14.92
ѱ (NatColo) β 1 (Dist_z) −1.18 ± 0.30*** N/A N/A
β 2 (Jul-2012) −2.58 ± 0.61*** N/A N/A
β 3 (Dec-2012) 1.69 ± 0.73* N/A N/A
β 4 (Jul-2013) 1.85 ± 0.73* N/A N/A
β 5 (Uniola and Leucaena) −0.17 ± 0.55 N/A N/A
ѱ (GrassColo) β 1 (Dist_z) N/A −1.28 ± 0.29*** N/A
β 2 (Jul-2012) N/A −2.42 ± 0.58*** N/A
β 3 (Dec-2012) N/A 2.12 ± 0.70** N/A
β 4 (Jul-2013) N/A 1.83 ± 0.69** N/A
β 5 (Megathyrsus and Uniola) N/A 0.01 ± 0.52 N/A
ѱ (InvColo) β 1 (Dist_z) N/A N/A 4.20 ± 1.04***
β 2 (Jul-2012) N/A N/A −6.44 ± 1.56***
β 3 (Dec-2012) N/A N/A 5.60 ± 1.44***
β 4 (Jul-2013) N/A N/A 5.97 ± 1.50***
β 5 (Megathyrsus and Leucaena) N/A N/A 0.19 ± 0.96
ѱ (AllColoNat) β 1 (Dist_z) −1.34 ± 0.33*** N/A N/A
β 2 (Jul-2012) 0.77 ± 1.65 N/A N/A
β 3 (Dec-2012) 1.65 ± 0.74* N/A N/A
β 4 (Jul-2013) 1.93 ± 0.75** N/A N/A
β 5 (Uniola and Leucaena) −0.29 ± 0.56 N/A N/A
β 6 (native vegetation) −3.43 ± 1.62* N/A N/A
ѱ (AllColoGrass) β 1 (Dist_z) N/A −1.39 ± 0.31*** N/A
β 2 (Jul-2012) N/A 0.19 ± 1.59 N/A
β 3 (Dec-2012) N/A 2.09 ± 0.70** N/A
β 4 (Jul-2013) N/A 1.89 ± 0.71** N/A
β 5 (Megathyrsus and Uniola) N/A −0.06 ± 0.53 N/A
β 6 (native vegetation) N/A −2.67 ± 1.55 N/A
ѱ (AllColoInv) β 1 (Dist_z) N/A N/A 4.20 ± 1.04***
β 2 (Jul-2012) N/A N/A −5.34 ± 15.55
β 3 (Dec-2012) N/A N/A 5.60 ± 1.44***
β 4 (Jul-2013) N/A N/A 5.97 ± 1.50***
β 5 (Megathyrsus and Leucaena) N/A N/A 0.19 ± 0.96
β 6 (native vegetation) N/A N/A −1.10 ± 15.48
  1. All models were tested for significance at α ≤ 0.01 (*), α ≤ 0.001 (**), α ≤ 0.00001 (***)