{"id":"repola-2009-picea-abies-total","source":{"id":"repola-2009","citation":"Repola, J. (2009). Biomass equations for Scots pine and Norway spruce in Finland. Silva Fennica, 43(4), 625–647.","title":"Biomass equations for Scots pine and Norway spruce in Finland","authors":["Repola, J."],"year":2009,"venue":"Silva Fennica","doi":"10.14214/sf.184","url":"https://doi.org/10.14214/sf.184","read_url":"https://silvafennica.fi/pdf/184","access":"open","license":"CC BY-SA 4.0","checked_at":"2026-11-01","status":"current"},"name":"Norway spruce total above-ground biomass, Model 1c (Eq. 17)","output":{"quantity":"agb"},"expression":"exp(-1.808 + 9.482 * (2 + 1.25*D)/((2 + 1.25*D) + 20) + 0.469 * ln(H) + (0.006 + 0.013)/2)","published":{"expression":"exp(-1.808 + 9.482 * (2 + 1.25*d)/((2 + 1.25*d) + 20) + 0.469 * ln(h) + (0.006 + 0.013)/2)","units":{"d":"cm","h":"m"},"variables":{"d":"D","h":"H"},"output_unit":"kg"},"taxon":{"level":"species","name":"Picea abies","family":"Pinaceae","group":"conifer"},"region":{"scope":"national","countries":["FI"],"place":"Finland, mineral-soil stands (mostly southern and central Finland)","biomes":["boreal"]},"stand":"mixed","fit":{"n_trees":166,"cf":1.00955,"method":"Multivariate linear mixed model on ln(biomass) with stand random effects (fitted jointly with component equations); fixed part shown, with variance correction (var(u)+var(e))/2 added to the intercept"},"evidence":[{"field":"expression","quote":"ln(yki) = b0 + b1 dSki/(dSki + 20) + b2 ln(hki) + uk + eki","locator":"Eq. 17, p. 633"},{"field":"expression","quote":"Total Eq. 17 N = 166 b0 –1.808 b1 9.482 b2 0.469 var(uk) 0.006 var(eki) 0.013","locator":"Table 7, p. 634"},{"field":"expression","quote":"dSki = 2 + 1.25 dki","locator":"variable definitions"},{"field":"fit.cf","quote":"a variance correction term, (σu² + σe²)/2 … should be added to the intercept","locator":"Section 2.4 (2009) / Section 3 (2008)"}],"check":[{"inputs":{"D":20,"H":18},"expected":149.0364,"origin":"computed","note":"computed from the published form (with variance correction) at d = 20 cm, h = 18 m"}],"verification":"original_read","checked_at":"2026-11-01","notes":"Total above-ground biomass of the stem wood, bark, living and dead branches and needles. dS = 2 + 1.25d. Variance correction (0.006+0.013)/2 = 0.0095 added to the intercept in both forms. Sample trees spanned d 1.7–41.7 cm and h 2.1–35.0 m (Table 3, all 613 trees); the total equation used 166 trees, so no fit range is stated. Mineral-soil stands, Finland."}