Table 1. Existing publications on single tree volume and stem shape models for teak. | |||

Source | Region | Model Application | Modelling Dataset |

Pérez and Kanninen (2003) | Costa Rica | Total and merchantable stem volume | 111 trees Age 2–47 years Diameter 2–59 cm |

Malimbwi et al. (2005) | Tanzania | Total stem volume | - |

van Zyl (2005) | Tanzania | Stem volume, height and form | 222 trees Diameter 8–79 cm Height 9–34 m |

Figueiredo et al. (2006) | Brazil | Stem volume and profile | 159 trees Age 7–10 years |

Pérez (2008) | Costa Rica | Total and merchantable stem volume | 25 trees Age 8–46 Diameter 9–55 cm |

Reggiani (2009) | Brazil | Total stem volume | - |

Figueiredo et al. (2014) | Brazil | Stem volume and height (a book with some 40 equations for teak volume and height) | - |

Ribeiro (2014) | Brazil | Stem heartwood volume | 40 trees Diameter 10–35 cm Height 14–27 m |

Fallas (2017) | Costa Rica | Total and merchantable stem volume of clonal teak trees | 306 trees Age 3–12 years Diameter 9–32 cm |

Table 2. Existing publications on stand-level growth and yield models for teak. | ||||

Source | Region | Model Application | Modelling Dataset | Comments |

Nunifu (1997) | Ghana | Stand-level yield models for dominant height, diameter, basal area, volume and biomass. Weibull model for diameter distribution modelling. | 100 sample plots Age 3–40 years | Modelling data includes only low yield sites |

Bermejo (2004) | Costa Rica | Yield models/tables based on dominant height development | 318 sample plots | Modelling data covers only first half of full rotation. |

Drescher (2004) | Brazil | Stand-level yield models for mean diameter, dominant height, form factor, stocking, basal area and volume | 162 sample plots Age 2–10 years Diameter 8–21 cm Height 10–18 m | Modelling data covers only first half of full rotation. |

Pérez and Kanninen (2005) | Costa Rica | Stand-level growth curves for mean diameter and dominant height as a function of age | 150 sample plots Age 1–47 years | |

García el al. (2006) | Brazil | Diameter distribution models for early thinning simulations | 239 sample plots Age < 96 months | |

Saraiva et al. (2006) | Brazil | Diameter distribution models for early thinning simulations | 239 sample plots Age < 96 months | Same data as in García et al. (2006) |

Batista (2007) | Brazil | Dominant height model for young teak plantations | Age < 12 years | |

Pérez (2008) | Costa Rica | Stand-level dominant height curve | 25 sample trees | |

Tewari et al. (2014) | India | Stand-level growth curves for dominant height, mortality, basal area and volume | 22 sample plots with 3 consecutive measurements Age 11–38 years |

Table 3. Soil characteristics in teak plantations in the study area and teak optimum requirements for soil parameters as reported in published literature. | |||||||

Soil Parameter | Unit | Method | N | Mean | St. Dev. | Teak Optimum | Source |

Sand | % | Bouyoucos | 305 | 20% | 11% | 55…65% | (1) |

Loam | % | Bouyoucos | 305 | 15% | 6% | … | … |

Clay | % | Bouyoucos | 305 | 65% | 13% | 35...45% | (1) |

Organic matter | % | Walkey-Black | 305 | 1.0% | 0.7% | 2.5…4.0+% | (1) |

pH | NA | Water 1:2.5 | 305 | 6.1 | 0.6 | 5.5…6.2…7.2 | (1) |

P | mg l^{–1} | Mehlich-1 | 305 | 10.2 | 20.1 | 3…10 | (1) (4) |

K | mg l^{–1} | Mehlich-1 | 305 | 157 | 98 | >40…120+ | (1) |

Ca | meq 100 g^{–1} | KCL | 305 | 23.1 | 13.2 | 1.5…4.0+ | (1) |

Mg | meq 100 g^{–1} | KCL | 305 | 7.4 | 8.3 | 1.0…4.0 | (1) |

Ca + Mg | meq 100 g^{–1} | KCL | 305 | 30.5 | 16.4 | 2.5…6.0+ | (1) |

Al | meq 100 g^{–1} | KCL | 305 | 0.6 | 1.3 | <0.2 | (1) |

CEC | meq 100 g^{–1} | Cation calculation | 305 | 31.7 | 16.2 | 4…10+ | (1) |

Acid saturation | % | (Al + H)/CEC | 305 | 4% | 10% | <3…8% | (2) (3) (4) |

Base saturation | % | (K + Ca + Mg)/CEC | 305 | 95% | 11% | n.a. | n.a. |

Calcium saturation | % | Ca/CEC | 305 | 69% | 11% | >40...62…75% | (2) (3) (4) (5) |

Teak optimum values according to: (1) Jerez and Coutinho (2017) (Brazil) (2) Alvarado and Fallas (2004) (Costa Rica) (3) Vaidés (2004) (Guatemala) (4) Mollinedo et al. (2005) (Panama) (5) Fernández-Moya et al. (2015) (Central America) |

Table 4. Number of sample plots in the yield model dataset. | |||

Age | SI_{20} < 25.5 | SI_{20} > 25.5 | Total n |

<10 | 791 | 971 | 1762 |

>10 | 472 | 400 | 872 |

Total n | 1263 | 1371 | 2634 |

Table 5. Stand parameter summary in the yield model dataset. | ||||||||||

Parameter | Age | D | D_{max} | D_{min} | H | Hd | N | G | V | SI_{20} |

Min | 1.5 | 3.7 | 4.7 | 0.5 | 3.2 | 3.5 | 20 | 0.2 | 1.2 | 9.5 |

Max | 19.9 | 43.3 | 54.4 | 39.0 | 29.9 | 30.3 | 1260 | 28.0 | 312.2 | 42.6 |

Mean | 8.9 | 20.3 | 24.1 | 15.6 | 17.4 | 18.0 | 441 | 11.2 | 98.8 | 25.5 |

Median | 7.7 | 20.4 | 24.2 | 15.9 | 17.8 | 18.3 | 360 | 11.3 | 95.9 | 25.6 |

D = mean diameter (cm); D_{max}, D_{min }= maximum and minimum diameters (cm); H = mean height (m); Hd = Dominant height (m); N = stocking (trees ha^{–1}); G = basal area (m^{2} ha^{–1}); V = total stem volume (m^{3} ha^{–1}); SI_{20 }= Dominant height at base age of 20 years (m). |

Table 6. Selected single-entry and double-entry stem volume models. | |||||

Model | Equation | N | R² | RMSE | Bias |

D8 | = –0.23959 + 0.036738 × d | 383 | 0.970 | 0.056 | –0.001 |

D10 | v = 8.2091 × exp(–70.331 / d) | 383 | 0.970 | 0.079 | +0.003 |

DH21 | v = 0.000032589 × d^{2} × h | 383 | 0.974 | 0.074 | +0.011 |

DH22 | v = 0.029387 + 0.000031543 × d^{2} × h | 383 | 0.973 | 0.073 | +0.000 |

DH29 | v = 0.000078168 × d^{2 }+ 0.00020175 × (h – 1.3)^{2} + 0.000025461 × d^{2} × h – 0.0000000094597 × d × h^{2} | 383 | 0.978 | 0.068 | –0.005 |

DH35 | v = 0.0028011 × d + 0.0059896 × (h – 1.3) + 0.000030872 × d^{2} × h | 383 | 0.978 | 0.066 | –0.003 |

v = stem volume (m^{3}); d = diameter at 1.3 m above the stump (cm); h = stem height (m). |

Table 7. Summary of Yield Models A, B and C. View in new window/tab. |