Effects of Rising Temperature on Carbon Cycling and Storage in Ecosystems
Earth's increasing temperatures may have large effects on ecosystem carbon process rates and storage in soils and vegetation, but a quantitative understanding of these effects remains elusive because realistic studies are hard to construct. Artificial heating studies typically warm only the soil and miss replicating the effects on the whole ecosystem. Forest Service scientists and their partners at the University of Hawai'i at Manoa used a highly constrained mean annual temperature gradient in Hawai'i where soils, vegetation, stand characteristics, natural forest disturbance history, and soil moisture are all highly controlled.
Coupling this gradient with detailed mass and radiocarbon-based measurements of the soil, litterfall, and growing vegetation, the scientists found that as ecosystems warm, they store more carbon, not less. Part of the reason for this relationship is that soil carbon decomposition does not accelerate with warming while stand productivity increases. The research findings suggest there will not be a positive feedback on warming due to accelerated loss of carbon from soils to the atmosphere.
Projections that show a positive feedback on warming that ranges from an accelerated carbon loss point to an ultimately more costly approach to mitigating warming—and so this research may provide economic benefits to society as countries prepare for development and adoption of mitigation strategies. This ongoing research occurred on the windward side of Hawai'i Island between 2008 and 2012 and will continue through 2015.
Forest Service Partners