Incorporating forest diversity in global change mitigation initiatives

DÍAZ S

Stanford, USA

Simposio; International Symposium on Tropical Dry Forests of Latin America; 2006

Stanford niversity, Department of Bilogical Sciences and Center for Latin American Studies

Most international agreements and assessment reports on climate change mitigation measures based on biological sequestration of carbon (C) have paid little attention to whether their effectiveness is influenced by biodiversity in the broad sense (i.e. the richness and composition of genotypes, populations, species and functional groups). This can have important consequences for both climate change mitigation and those ecosystem services that depend on biodiversity. We firstly review theory and empirical findings about how forest biodiversity may influence carbon sequestration through its effects on both aboveground and belowground processes. We then use this information to propose guidelines that could be taken in order to maximize C sequestration in forest ecosystems. Based on reviewing the evidence we suggest that: (1) On the bases of biodiversity theories, new evidence, and previous biogeochemical work, the protection of primary forests is probably the most effective C sequestration option possible, and it is therefore desirable to include these forests in future international negotiations related to climate change, including those linked to the Kyoto Protocol; (2) The maximization of short-term C uptake is unlikely to be the best option for C sequestration in the longer term, meaning that emphasis should also be put on avoiding losses, rather than just on increasing C gains; and (3) The incorporation of a high specific and genotypic richness, and the careful choice of dominant and subdominant species and genotypes, would be the safest option for C  sequestration in plantations and agroforestry systems, given the state of current knowledge. Overall,  biodiversity should be recognized as a key determinant of the success of climate change mitigation  initiatives based on C sequestration in primary, managed, and planted forests, notably those related to  the Kyoto Protocol.