Abstract

Since the publication of the IPCC special report on Land Use, Land Use Change and Forestry, considerable advances in our understanding of the global carbon cycle have occurred. This report attempts to review the terrestrial part of that cycle and assesses the implications for the implementation of then Kyoto protocol. The review assesses the impacts of the effects of continuing carbon uptake of old growth forest, interannual variability of terrestrial uptake. It is speculated that impact on N-deposition on carbon sequestration is small (of order 10%). It is unknown whether agriculture at large is a source or sink. Lack of knowledge of soil organic carbon contributes strongly to this uncertainty. The sustainability of the terrestrial sink also reviewed. It is concluded that eventually all sinks saturate, but that land use management can play a critical role in sustaining the sink strength. The role of feedback of the terrestrial carbon pools on climate change is discussed.