{"id":"mwakalukwa-2014-trees-wd","source":{"id":"mwakalukwa-2014","citation":"Mwakalukwa, E.E., Meilby, H., Treue, T. (2014). Volume and Aboveground Biomass Models for Dry Miombo Woodland in Tanzania. International Journal of Forestry Research, 2014, 531256.","title":"Volume and Aboveground Biomass Models for Dry Miombo Woodland in Tanzania","authors":["Mwakalukwa, E.E.","Meilby, H.","Treue, T."],"year":2014,"venue":"International Journal of Forestry Research","doi":"10.1155/2014/531256","url":"https://doi.org/10.1155/2014/531256","read_url":"https://onlinelibrary.wiley.com/doi/10.1155/2014/531256","access":"open","checked_at":"2026-11-02","status":"current"},"name":"Dry miombo, total AGB, Trees (28 species), D, H and wood density","output":{"quantity":"agb"},"expression":"1.0086 * exp(-9.188 + 0.9668 * ln(1000 * rho * D^2 * H))","published":{"expression":"1.0086 * exp(-9.188 + 0.9668 * ln(wd * DBH^2 * HT))","units":{"wd":"kg/m3","DBH":"cm","HT":"m"},"variables":{"wd":"rho","DBH":"D","HT":"H"},"output_unit":"kg"},"taxon":{"level":"mixed","name":"Trees, 28 species","group":"broadleaf"},"region":{"scope":"site","countries":["TZ"],"place":"Gangalamtumba Village Land Forest Reserve, Iringa, Tanzania (dry miombo woodland)","biomes":["tropical","dryland"]},"stand":"natural","fit":{"n_trees":72,"dbh_min_cm":1.4,"dbh_max_cm":62,"h_min_m":2.5,"h_max_m":18.2,"r2":0.996,"cf":1.0086,"method":"linear mixed model on ln-transformed data (species random effect)"},"evidence":[{"field":"expression","quote":"Trees (N = 72); 28 species ... Total biomass ... (df = 70) 6 −9.1880 (0.101) 0.9668 (0.007) — 1.4–62 0.996 0.131 0.052 1.32","locator":"Table 2, total biomass, model 6"},{"field":"fit.cf","quote":"CF = exp⁡(RMSE2/2), which was applied to the predicted values of volume and biomass","locator":"Section 2.5 (Sprugel correction)"},{"field":"published.units","quote":"Y is volume (m3) or biomass (kg); Dbh is diameter at breast height (cm); ht is total height (m); and wd is wood density (kg m−3).","locator":"Table 2 note"},{"field":"fit.dbh_max_cm","quote":"The minimum and maximum sizes of sample trees/shrubs were 1.4 cm and 62.0 cm in diameter at breast height","locator":"Section 2.2 (study-wide)"}],"check":[{"inputs":{"D":20,"H":10,"rho":0.6},"expected":151.99,"origin":"computed","note":"hand-computed from the published form"},{"inputs":{"D":40,"H":14,"rho":0.7},"expected":933,"origin":"computed","note":"hand-computed from the published form"}],"verification":"original_read","checked_at":"2026-11-02","notes":"ln-ln OLS (species models) or linear mixed model with species random effect (group models); total aboveground biomass is stump + stem and branches + twigs and leaves, so foliage is included. The paper states CF = exp(RMSE²/2) and that it was applied to predictions; the CF value (1.0086) is not printed and is computed here from the printed RMSE (0.131) by that stated formula, and applied in both forms. The R² shown for group models is the likelihood-ratio R² named in the Table 2 note; for species models it is adjusted R². Wood density is in kg/m³ per the table note (the text says g/cm³ in one place); the coefficients only give plausible values with kg/m³. The canonical form multiplies rho (g/cm³) by 1000."}