{"id":"qirom-2020-non-dipterocarpaceae-ln-d","source":{"id":"qirom-2020","citation":"Qirom, M. A., & Akbar, A. (2020). Model Volume Kelompok Jenis Pohon pada Hutan Rawa Gambut di IUPHHK PT. Tingang Karya Mandiri, Kalimantan Tengah [The Volume Model of Tree Species Group in Peat Swamp Forest at Logging Concession Area of Tingang Karya Mandiri, Central Kalimantan]. Jurnal WASIAN, 7(1), 1-14.","title":"Model Volume Kelompok Jenis Pohon pada Hutan Rawa Gambut di IUPHHK PT. Tingang Karya Mandiri, Kalimantan Tengah","authors":["Qirom, M. A.","Akbar, A."],"year":2020,"venue":"Jurnal WASIAN","doi":"10.20886/jwas.v7i1.5538","url":"https://doi.org/10.20886/jwas.v7i1.5538","read_url":"https://pub.kehutanan.unismuh.ac.id/index.php/wasian/article/download/97/88","access":"open","checked_at":"2026-11-02","status":"current"},"name":"Peat swamp forest, non-Dipterocarpaceae group, volume from D (model 1)","output":{"quantity":"stem_volume"},"expression":"exp(-8.398596 + 2.4688 * ln(D))","published":{"expression":"exp(-8.398596 + 2.4688 * ln(DBH))","units":{"DBH":"cm"},"variables":{"DBH":"D"},"output_unit":"m3"},"taxon":{"level":"mixed","name":"Non-dipterocarp species group (P. rostratum, C. soulattri, D. pectinatum, as printed)","group":"broadleaf"},"region":{"scope":"site","countries":["ID"],"place":"IUPHHK PT Tingang Karya Mandiri peat swamp forest, Central Kalimantan","biomes":["tropical"]},"stand":"natural","fit":{"n_trees":42,"dbh_min_cm":5.6,"dbh_max_cm":27,"h_min_m":6,"h_max_m":24,"r2":0.973,"method":"ordinary least squares on ln(V) = a0 + a1 ln(D)"},"evidence":[{"field":"expression","quote":"ln (V ) = -8.398596 + 2.4688 ln (D ) ... R2 97,3 %","locator":"Best model, non-Dipterocarpaceae group, p. 10 (Tabel 3 model 1)"},{"field":"fit.n_trees","quote":"Kelompok non-dipterocarpaceae Diameter 13,9 5,6 27,0 6,0 42","locator":"Tabel 1, Penyusunan Model"}],"check":[{"inputs":{"D":8},"expected":0.038202,"origin":"computed","note":"computed from the published form (coefficients as printed)"},{"inputs":{"D":15},"expected":0.18033,"origin":"computed","note":"computed from the published form (coefficients as printed)"},{"inputs":{"D":25},"expected":0.63646,"origin":"computed","note":"computed from the published form (coefficients as printed)"}],"verification":"original_read","checked_at":"2026-11-02","notes":"Volume to a 5 cm top diameter by Smalian's formula on 2 m sections (stem volume, no branches). Diameter was taken at 1.3 m or 20 cm above ground (as printed: 'setinggi dada (1,3 m) atau 20 cm di atas permukaan tanah'); the paper does not say which trees used which. Natural-log form as printed, with no correction factor stated. Fit ranges are those of the model-development subset (70% of the trees, Table 1). Caution: Tabel 3 prints identical coefficients for models 1, 2, 5 and 6 in both the Dipterocarpaceae and non-Dipterocarpaceae groups (with different F and Se values), which looks like a typesetting error in the paper; the text on p. 10 attributes this model 1 to the non-Dipterocarpaceae group, which is the reading used here."}