Relationship Between Plant Biomass and Gas Flux At Busby Forest.

Understanding of the relationship between plant biomass and fluxes of greenhouse is important in the estimation and monitoring of carbon stocks and greenhouse gas fluxes.  We conducted an inventory of tree species in a 0.49 ha forest plot at Lincoln University’s Busby forest in Jefferson City, Missouri. A total of four hundred twenty seven trees belonging to twenty three species were geospatially referenced, tagged and their diameters at breast (DBH) measured. Then, we calculated foliage biomass (FBM), branch biomass (BBM), stem biomass (SBM), root biomass (RBM) and total biomass (TBM). Using data on greenhouse gases (CO₂, CH₄ and N₂O) measured at this site, we developed linear trend surface models between each of these gases and their coordinates (Latitude and Longitude). These models were later used to predict CO₂, CH₄ and N₂O at locations where tree species were geo-referenced.  Finally, we conducted Pearson correlation analysis to evaluate the relationship between plant biomass and greenhouse gases fluxes. Results showed that, except for foliage biomass (FBM), all plant biomass parameters were significantly correlated with greenhouse fluxes with correlation coefficients (r) ranging from 0.14 to 0.19. Branch biomass (BBM) had the highest correlation coefficients with CO₂ (p=0.0002, r= 0.19); CH₄ (p=0.0004, r=0.18) and N₂O (p=0.005, r= 0.18). The low correlation coefficient (r) can be explained by the predictive models for which the coefficients of determination (R²) were significant, but also low. Further studies will be conducted to better understand the relationship between plant biomass and gas fluxes.