The relevance of using in situ carbon and nitrogen data and satellite images to assess aboveground carbon and nitrogen stocks for supporting national REDD + programmes in Africa

Abstract

Background To reduce the uncertainty in estimates of carbon emissions resulting from deforestation and forest degradation, better information on the carbon density per land use/land cover (LULC) class and in situ carbon and nitrogen data is needed. This allows a better representation of the spatial distribution of carbon and nitrogen stocks across LULC. The aim of this study was to emphasize the relevance of using in situ carbon and nitrogen content of the main tree species of the site when quantifying the aboveground carbon and nitrogen stocks in the context of carbon accounting. This paper contributes to that, by combining satellite images with in situ carbon and nitrogen content in dry matter of stem woods together with locally derived and published allometric models to estimate aboveground carbon and nitrogen stocks at the Dassari Basin in the Sudan Savannah zone in the Republic of Benin. Results The estimated mean carbon content per tree species varied from 44.28 ± 0.21% to 49.43 ± 0.27%. The overall mean carbon content in dry matter for the 277 wood samples of the 18 main tree species of the region was 47.01 ± 0.28%—which is close to the Tier 1 coefficient of 47% default value suggested by the Intergovernmental Panel on Climate Change (IPCC). The overall mean fraction of nitrogen in dry matter was estimated as 0.229 ± 0.016%. The estimated mean carbon density varied from 1.52 ± 0.14 Mg C ha−1 (for Cropland and Fallow) to 97.83 ± 27.55 Mg C ha−1 (for Eucalyptus grandis Plantation). In the same order the estimated mean nitrogen density varied from 0.008 ± 0.007 Mg ha−1 of N (for Cropland and Fallow) to 0.321 ± 0.088 Mg ha−1 of N (for Eucalyptus grandis Plantation). Conclusion The results show the relevance of using the in situ carbon and nitrogen content of the main tree species for estimating aboveground carbon and nitrogen stocks in the Sudan Savannah environment. The results provide crucial information for carbon accounting programmes related to the implementation of the REDD + initiatives in developing countries.

The Contribution of Trees Outside of Forests to Landscape Carbon and Climate Change Mitigation in West Africa

“…Allometric equations are commonly used to estimate biomass and carbon stocks, however, there is limited reporting on allometric models for TOF, especially in African savannas and woodlands [32]. The estimation of carbon stocks in sub-Saharan Africa is frequently based on allometric models in conjunction with forest inventory data [33,34].…”

Biomass Carbon and Nitrogen allocation in different tree species: do tree compartments and size affect C:N relationship?

“…The accuracy of biomass C and N stock evaluation in forests depends on reliable estimates of C and N concentrations per plant species and organs (Ma et al 2019;Chabi et al 2019). The variation of N and C in plant organs can be quantified by a stoichiometric scaling relationship, which shows the relative accumulation rate of N compared to C and can be interpreted as the proportional relationships between them.…”