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Notes
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. The variables, where not self-explanatory, are described below: Identification variables Case number: Sorting variable Farmer ID: coded identifier of owner of the land when the block was planted. ICRAF holds the name of each of these individuals. Zone: locality where planted, as follows: NR: Nueva Requena CURI: Curimaná SA: San Alejandro CFB: Carretera Federico Basadre TOUR: Tournavista Plot: Number of the plot, nested within each species (i.e. number are non-unique) Bolaina: indicator variable for species. 1=Guazuma crinita, 0=not Guazuma crinita Capirona: indicator variable for species. 1=Calycophyllum spruceanum, 0=not Calycophyllum spruceanum Pijuayo: indicator variable for species. 1= Bactris gasipaes, 0=not Bactris gasipaes Growth variables Annualized diameter increment: Basal diameter of all trees in each block were measured at ages between 12-14 months (Guazuma crinita), 15-17 months (Calycophyllum spruceanum), and 18 months (Bactris gasipaes). Mean monthly increments were calculated and then, for ease of presentation and comparison, converted these to annual increments (i.e., multiplying by 12); increments were used in order to minimize confounding of block (i.e. site) effects with measurement ages. Annualized height increment: Height of all trees in each block were measured at ages between 12-14 months (Guazuma crinita), 15-17 months (Calycophyllum spruceanum), and 18 months (Bactris gasipaes). Mean monthly increments were calculated and then, for ease of presentation and comparison, converted these to annual increments (i.e., multiplying by 12); increments were used in order to minimize confounding of block (i.e. site) effects with measurement ages. Site variables Soil samples were collected at 0-15cm during the establishment of each plot. pH: soil pH in 1:1 soil:water suspension P: available P (modified Olsen method) K: Available K Ca: Exchangeable Ca2+ Mg2+: Exchangeable Mg2+ (ammonium acetate, quantification by atomic absorbtion); CEC: cation exchange capacity (ammonium acetate saturation method, pH7.0) Al Sat: Al3+ saturation (Yuan method, extraction with KCl, N) Organic matter: % (oxidation with potassium dichromate) Proportions of sand, silt, and clay: hydrometer method). FALLOW: indicator variable for previous land use (1=bush fallow, 0=not bush fallow) AGRICULTURE: indicator variable for previous land use (1= agriculture, i.e. cultivation of maize or rice, 0=not agriculture) PASTURE: indicator variable for previous land use (1= pastureland, 0=not pastureland) Land use was categorized based on direct observations and conversations with the landowners at time of establishment.
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