{"id":"poudel-2019-picea-sitchensis","source":{"id":"poudel-2019","citation":"Poudel, K. P., Temesgen, H., Radtke, P. J., & Gray, A. N. (2019). Estimating individual-tree aboveground biomass of tree species in the western U.S.A. Canadian Journal of Forest Research, 49(6), 701-714.","title":"Estimating individual-tree aboveground biomass of tree species in the western U.S.A.","authors":["Poudel, K. P.","Temesgen, H.","Radtke, P. J."],"year":2019,"venue":"Canadian Journal of Forest Research","doi":"10.1139/cjfr-2018-0361","url":"https://doi.org/10.1139/cjfr-2018-0361","read_url":"https://vtechworks.lib.vt.edu/bitstreams/13666b54-8fb3-444c-8f8f-f54bc602a4b9/download","access":"open","checked_at":"2026-11-02","status":"current"},"name":"Sitka spruce total aboveground biomass from DBH and height (Table 4)","output":{"quantity":"agb"},"expression":"1.0091 * exp(-2.5826 + 1.8196 * ln(D) + 0.7108 * ln(H))","published":{"expression":"1.0091 * exp(-2.5826 + 1.8196 * ln(DBH) + 0.7108 * ln(HT))","units":{"DBH":"cm","HT":"m"},"variables":{"DBH":"D","HT":"H"},"output_unit":"kg"},"taxon":{"level":"species","name":"Picea sitchensis","family":"Pinaceae","group":"conifer"},"region":{"scope":"regional","countries":["US"],"place":"Western U.S.A., legacy destructive-sampling biomass collection (Radtke et al. 2015)","biomes":["temperate"]},"stand":"mixed","fit":{"n_trees":19,"dbh_min_cm":7.2,"dbh_max_cm":47.8,"h_min_m":4.6,"h_max_m":40.7,"cf":1.0091,"method":"regression on ln(AGB) with Baskerville log-bias correction factor"},"evidence":[{"field":"expression","quote":"Sitka spruce  a, b, c, d, CF: −2.5826  1.8196  0.7108  CF 1.0091; model form exp(a + bX1 + cX2)","locator":"Table 4, species row and table note"},{"field":"fit.n_trees","quote":"Sitka spruce ... n 19","locator":"Table 1"},{"field":"fit.dbh_min_cm","quote":"Sitka spruce DBH min 7.2 max 47.8; HT min 4.6 max 40.7","locator":"Table 1"}],"check":[{"inputs":{"D":20,"H":15},"expected":121.7994,"origin":"computed","note":"computed from the Table 4 coefficients"},{"inputs":{"D":40,"H":25},"expected":618.1436,"origin":"computed","note":"computed from the Table 4 coefficients"}],"verification":"original_read","checked_at":"2026-11-02","notes":"AGB is total aboveground live-tree biomass (stem, bark, branches, foliage). X1 = ln(DBH), X2 = ln(HT), DBH in cm and HT in m. Species identified from the common name in Table 4 (scientific name added from the standard species symbol). Stand type is not stated. Observed ranges in Table 1 cover all trees of the species used."}