{"id":"brown-1997-pine","source":{"id":"brown-1997","citation":"Brown, S. (1997). Estimating Biomass and Biomass Change of Tropical Forests: a Primer. FAO Forestry Paper 134. Rome: Food and Agriculture Organization of the United Nations. ISBN 92-5-103955-0.","title":"Estimating Biomass and Biomass Change of Tropical Forests: a Primer (FAO Forestry Paper 134)","authors":["Brown, S."],"year":1997,"venue":"FAO Forestry Paper 134","url":"https://www.fao.org/4/w4095e/w4095e00.htm","read_url":"https://www.fao.org/4/w4095e/w4095e06.htm","access":"open","checked_at":"2026-11-01","status":"current"},"name":"Tropical pines AGB from DBH (Eq. 3.1.8 / 3.2.8)","output":{"quantity":"agb"},"expression":"exp(-1.170 + 2.119 * ln(D))","published":{"expression":"exp(-1.170 + 2.119 * ln(D))","units":{"D":"cm"},"output_unit":"kg"},"taxon":{"level":"genus","name":"Pinus","family":"Pinaceae","group":"conifer"},"region":{"scope":"global","countries":["US","IN","PR"],"place":"Pine stands in the southeastern USA, India and Puerto Rico; offered for tropical pine forests","biomes":["tropical","subtropical"]},"stand":"mixed","fit":{"n_trees":63,"dbh_min_cm":2,"dbh_max_cm":52,"r2":0.98},"evidence":[{"field":"expression","quote":"Y(kg) = exp{-1.170+2.119*ln(D)}","locator":"Eq. 3.1.8, Section 3.2.1 table"},{"field":"published.units","quote":"Y= biomass per tree in kg, D = dbh in cm, and BA = basal area in cm2","locator":"Section 3.2.1, biomass regression equations table header"},{"field":"fit.n_trees","quote":"D = dbh, cm; range in dbh = 2-52 cm; number of trees =63; adjusted r 2 =0.98","locator":"Section 3.2.1, conifer forests"}],"check":[{"inputs":{"D":20},"expected":177.32,"origin":"computed","note":"computed with python3 from the published form"}],"verification":"original_read","checked_at":"2026-11-01","notes":"Preliminary equation from harvested pines in eight literature sources (southeastern USA, India, Puerto Rico), several Pinus species pooled. The HTML labels it Eq. 3.1.8 while the text calls it Eq. 3.2.8. r2 is adjusted r². The primer does not say whether a log back-transform correction is included; none applied. Stand origin (plantation vs natural) not stated."}