Publications des agents du Cirad

Cirad

Integrative modelling approach to assess the sustainability of the Eucalyptus plantation in Congo

Saint André L., Laclau J.P., Bouillet J.P., Deleporte P., Miabala A., Ognouabi N., Baillères H., Nouvellon Y., Moukini R.. 2002. In : IUFRO. Fourth Workshop IUFRO S5.01.04, Canada, September 8615, 2002. s.l. : s.n., p. 1-11. Workshop IUFRO S5.01.04. 4, 2002-09-08/2002-09-15, (Canada).

Since 1978, 42000 ha of clonal Eucalyptus plantations have been established in the littoral savannas of Congo, mainly for pulpwood production. These plantations were established on sandy soils, characterised by low reserves of available nutrients and a low water retention capacity. An intensive silviculture is carried out, resulting in the removal of high amounts of biomass and nutrients every 7 years. Therefore, a decision-making tool is needed (i) to assess stand productions under different silvicultural options, (ii) to evaluate the risks of nutrient deficiencies and non sustainable production, and (iii) to estimate the economic return of different harvesting strategies. For many years, field trials have been established focusing on clonal selection, silvicultural practices, stand growth and quantification of the biogeochemical cycles of nutrients. This high amount of data was used (or will be used) to elaborate a chain of models named "EUCALYPT-Dendro" that includes three main modules; - the growth module: a single tree distance-independent model was elaborated. The dominant height growth model is similar to the equation developed by Dhôte (1996). However, two main differences can be reported: (i) the model was segmented in order to take into account a change in height growth rate that occurs during stand rotation, (ii) tree spacing affected the dominant height growth and was introduced as regressor in the equation. The stand basal area increment is function of the dominant height increment. Individual tree basal area is function of a potential (given by the stand basal area increment) and a reductor (given by the size of the tree). The height of the trees is obtained from a height - girth relationship. Tree mortality is not yet taken into account (but in our case, tree mortality is limited owing to the short rotation length); - the tree properties module: a generic stem taper equation was constructed. It explicitly takes into account the global taper of the bol

Mots-clés : eucalyptus; plantation forestière; modèle; durabilité; république démocratique du congo

Communication de congrès

Agents Cirad, auteurs de cette publication :