Future direction
The research areas reviewed here can all be expected to make significant progress over the next decade. There will be a substantial expansion of data sets in all fields, but methodological issues must still remain a focus of research.
For studies based on global atmospheric CO2 concentrations, there needs to be an expansion of data points in poorly monitored regions, including tropical oceanic and continental regions, and improvements in the modeling of global trace gas transport, particularly between the tropics and the mid-latitudes.
For eddy covariance and other micrometeorological studies, the key question will be to explain the high C uptake rates currently being measured in tropical forests. Recently initiated field studies will provide a substantial data set, but attention still needs to be focused on unresolved methodological issues.
Long-term tropical forest plots offer great potential for direct monitoring of aboveground C stocks. There will be a substantial expansion of available data when all historical long-term forest plot records are compiled; however, these historical data sets will have several statistical and methodological problems. A more rigorous approach will be the establishment of large plots specifically tailored for research into long-term change, such as the 50 ha plots within the Centre for Tropical Forest Science network 。
The final point of convergence will be when field studies, laboratory studies and physiological models converge on a consistent picture of the C balance of each biome. This article has hinted at convergence between these diverse fields; we are optimistic that a more consistent picture of the net C balance of tropical forests, and of other biomes, will emerge over the next decade.