{"id":"da-silva-2015-ms-d2hrho","source":{"id":"da-silva-2015","citation":"Da Silva, F., Suwa, R., Kajimoto, T., Ishizuka, M., Higuchi, N., & Kunert, N. (2015). Allometric Equations for Estimating Biomass of Euterpe precatoria, the Most Abundant Palm Species in the Amazon. Forests, 6(2), 450–463.","title":"Allometric Equations for Estimating Biomass of Euterpe precatoria, the Most Abundant Palm Species in the Amazon","authors":["Da Silva, F.","Suwa, R.","Kajimoto, T."],"year":2015,"venue":"Forests","doi":"10.3390/f6020450","url":"https://doi.org/10.3390/f6020450","read_url":"https://www.mdpi.com/1999-4907/6/2/450/htm","access":"open","license":"CC BY 4.0","checked_at":"2026-11-02","status":"current"},"name":"Euterpe precatoria stem mass from D2Hrho","output":{"quantity":"stem_biomass"},"expression":"exp(-2.11) * (D^2 * Hstem * rho)^0.90","published":{"expression":"exp(-2.11) * (D^2 * H * rho)^0.90","units":{"D":"cm","H":"m","rho":"g/cm3"},"variables":{"H":"Hstem"},"output_unit":"kg"},"taxon":{"level":"species","name":"Euterpe precatoria","family":"Arecaceae","group":"palm"},"region":{"scope":"site","countries":["BR"],"place":"Terra-firme forest at the INPA forest-management field station, ~60 km NW of Manaus, Amazonas","biomes":["tropical"]},"stand":"natural","fit":{"n_trees":20,"dbh_min_cm":3.9,"dbh_max_cm":12.7,"h_min_m":2.3,"h_max_m":16.4,"method":"Power function fitted on ln-ln by standardized major axis (SMA)"},"evidence":[{"field":"expression","quote":"Ms D2Hρ −2.11 (−2.43–−1.79) 0.90 (0.84–0.96) 0.982","locator":"Table 1 (columns lng, h, adjusted R2; model ln y = ln g + h ln x, Eq. 2)"},{"field":"fit.n_trees","quote":"We harvested twenty palms","locator":"Abstract"}],"check":[{"inputs":{"D":8,"rho":0.4,"Hstem":10},"expected":17.826,"origin":"computed","note":"computed from Table 1 ln g and h"},{"inputs":{"D":12,"rho":0.5,"Hstem":15},"expected":65.121,"origin":"computed","note":"computed from Table 1 ln g and h"}],"verification":"original_read","checked_at":"2026-11-02","notes":"H is stem height from the stem base to the tip of the meristem (palm, fronds not included), mapped to canonical H. rho is the measured stem specific gravity (oven-dry mass / green volume), which the authors found rises with size, so applying this to unmeasured palms needs a rho estimate. Dry mass (fresh mass converted with component water content, dried at 65 C). SMA fit, no correction factor stated. Recommended: best predictor for Ms (adjusted R2 0.982 in Table 1). Coefficient is exp(lng) from Table 1 as printed. Not included: leaf mass (needs frond count Nf, not canonical) and root mass (Table 1 row and text disagree on the predictor). Palm height is measured from stem base to the meristem tip, fronds excluded; mapped to Hstem (closest canonical variable), not total height."}