{"id":"bocko-2023-m13-base-diameter-ge5","source":{"id":"bocko-2023","citation":"Bocko, Y.E., Panzou, G.J.L., Dargie, G.C., Mampouya, Y.E.W., Mbemba, M., Loumeto, J.J., Lewis, S.L. (2023). Allometric equation for Raphia laurentii De Wild, the commonest palm in the central Congo peatlands. PLoS ONE, 18(4), e0273591.","title":"Allometric equation for Raphia laurentii De Wild, the commonest palm in the central Congo peatlands","authors":["Bocko, Y.E.","Panzou, G.J.L.","Dargie, G.C."],"year":2023,"venue":"PLoS ONE","doi":"10.1371/journal.pone.0273591","url":"https://doi.org/10.1371/journal.pone.0273591","read_url":"https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0273591&type=printable","access":"open","license":"CC BY 4.0 (Creative Commons Attribution License)","checked_at":"2026-11-02","status":"current","notes":"Read the full open PDF. Four of the 22 models in Table 2 are captured: the single-predictor models on stem base diameter (m2, m13) and total palm height (m4, m15), the only ones using canonical variables. The paper's best models use the sum of petiole diameters (SDp, m1, m7, m11, m12, m18) and tissue density, which are not canonical variables and are not captured. Destructive sampling of 90 palms."},"name":"Raphia laurentii AGB from stem base diameter (m13, mean petiole diameter ≥5 cm)","output":{"quantity":"agb"},"expression":"1.11 * exp(-5.737 + 3.048 * ln(DRC))","published":{"expression":"1.11 * exp(-5.737 + 3.048 * ln(D))","units":{"D":"cm"},"variables":{"D":"DRC"},"output_unit":"kg"},"taxon":{"level":"species","name":"Raphia laurentii","group":"palm"},"region":{"scope":"site","countries":["CG"],"place":"Peat swamp forest near Bolembe, Likouala Department, Republic of the Congo","biomes":["tropical"]},"stand":"natural","fit":{"n_trees":60,"cf":1.11,"method":"ln-ln linear regression times correction factor CF = exp(RSE²/2)"},"evidence":[{"field":"expression","quote":"m13 ln(AGB) = a + b × ln(D) -5.737 3.048 0.69 0.45 77.3 48.07 -3.76 1.11","locator":"Table 2, m13 row (AGB in kg dry mass); CF defined in Methods, p. 5"},{"field":"notes","quote":"The aboveground biomass estimated from each logarithmic linear model was multiplied by the following correction factor","locator":"Development of allometric equations, p. 5"},{"field":"fit.n_trees","quote":"Table 2 range (n): 5–15 cm (60)","locator":"Table 2, mean petiole diameter range (n) column"}],"check":[{"inputs":{"DRC":10},"expected":3.9974,"origin":"computed","note":"computed from the published form (coefficients and CF as printed)"},{"inputs":{"DRC":20},"expected":33.061,"origin":"computed","note":"computed from the published form (coefficients and CF as printed)"},{"inputs":{"DRC":30},"expected":113.77,"origin":"computed","note":"computed from the published form (coefficients and CF as printed)"}],"verification":"original_read","checked_at":"2026-11-02","notes":"Whole-palm aboveground dry biomass (stem, sheaths, petioles, rachis and leaflets, so foliage is included). Stem base diameter was measured about 13 cm above the ground, mapped to DRC (root collar / stem base diameter); the fitted range of this variable is 8.20–35.40 cm (Table 1, all 90 palms), which is not DBH so it is not stored as a DBH range. Fitted on palms with mean petiole diameter 5–15 cm (60 palms); ranges of the subset are not given. CF is the printed correction factor (rounded to 2 decimals) and is applied in the expression. Single-predictor model: the paper's better models use the sum of petiole diameters (not a canonical variable; not captured), so this is a fallback for when only diameter or height is measured. R² adj printed: 0.69; RSE 0.45 (Table 2)."}