Table 1. Measurements of aboveground biomass (AGB) by local community members and professional foresters in four Southeast Asian countries, with p values for total biomass estimates (matched pair t test) and variance (F test), tree girth measurement (Wilcoxon signed rank test), and plot demarcation (Wilcoxon signed rank test) (n = 289 permanent plots). Significant values are shown in bold (n.a. = not available).

Country Name of area
(site number)
Number of plots Community survey of biomass
(Mean AGB in Mg · ha-1)
Forester survey of biomass
(Mean AGB in Mg · ha-1)
Biomass estimates (square root transformed)
p
Variance of biomass estimates (square root transformed)
p
Tree girth
(cm)
p
Plot demarcation
(Tree inclusion and exclusion)
p
Indonesia Batu Majang (a) 64 381‡ 449‡ <0.01 0.048 n.a.§ < 0.01 (20%)
China Manlin (b) 30 332 303 <0.01 0.51 n.a.§ 0.26 (23%)
China Manlin (c) 30 235 219 0.32 0.34 n.a.§ 0.15 (0%)
Laos Sakok (d) 32 293 301 0.21 0.57 < 0.01 (38%) n.a. | (97%)
Laos Sakok (e) 30 204 208 0.02 0.41 < 0.01 (53%) n.a. | (88%)
Vietnam Diem (f) 30 106 104 0.34 0.34 0.60 (47%) 0.02 (60%)
Vietnam Moi (g) 18 105 105 0.56 0.63 0.051 (54%) 0.67 (22%)
Vietnam Moi (h) 28 89.0 88.9 0.94 0.46 0.38 (53%) 0.05 (50%)
Vietnam Moi (i) 27 50.7‡ 52.3‡ 0.20‡ 0.41‡ 0.02 (47%) 0.38 (56%)
†In brackets, the proportion of measured trees (tree girth) and plots (plot demarcation) where community members’ and foresters’ measurements had a perfect match.
‡One plot was excluded because it violated 3x standard deviation of the mean. (For Batu Majang, Indonesia, n = 63; for Moi [i], Vietnam, n = 26)
§ Data are not available because trees were not individually marked.
| No p value is available because too few degrees of freedom exist for Wilcoxon’s signed rank test.