A study of biomass allocation schemes in A Land Surface Model

Modelling of the biomass allocation is important for simulating the carbon dynamics in terrestrial ecosystems in land-surface models, but it is less studied. Nowadays the simple constant allocation scheme has still been widely used in many land-surface models, even though it is not enough to describe the biomass allocation appropriately. In this paper a new scheme for partitioning the products of photosynthesis towards different biomass components in forest ecosystem was developed for using in the land surface models. By implementing the new scheme in the Community Atmosphere-Biosphere-Land Exchange (CABLE) land-surface model, we compared the results of the model using the new scheme with those with an old scheme (a constant allocation scheme) against the observations. We found that the estimated results of the Gross Primary Production (GPP) using the new scheme are about 10% lower than those using the old scheme and closer to the observed values. Accordingly, it also could be found that the plant carbon pool sizes calculated from the new allocation scheme are smaller and more reasonable than those from the old one.