ESTIMATION OF ABOVEGROUND BIOMASS FOR A DOMINANT HERBACEOUS SPECIES IN A NORTHERN SUBTROPICAL FOREST USING HEIGHT AND COVERAGE

An estimation of the aboveground biomass of herbaceous plants is of significant value for the evaluation of carbon storage in subtropical herbaceous layers. To estimate the aboveground biomass of eight common herbaceous species in subtropical forests in Anhui Province, China, single and mixed multi-species allometric models were established using the average height, coverage, and complex variables (average height was multiplied by the coverage) as independent variables. The results showed that the coverage and complex variables were strongly correlated with the aboveground biomass of herbaceous plants, which were suitable predictors for modeling. The complex variables, except for Selaginella moellendorffii, revealed a good fit accuracy when used as the prediction variable, with R-2 values ranging from between 0.649 and 0.904. Compared with the allometric model of specific species, the R-2 of the mixed species model was lower (R-2 = 0.49); however, the MPE (Mean Predictive Error, MPE) was low and within the allowable error range (MPE = -8.599%). The nine optimal allometric models established in this study proved that average height and coverage possessed high predictive capacities for herbaceous biomass. This provided a new approach for the measurement and monitoring of forest productivity in subtropical areas.