Roots: The Hidden Half of Vegetation-Climate Interactions
In this guest contribution, Dr. Rebecca Neumann describes how that much of the Earth's land surface is covered by vegetation that “breathes” carbon dioxide “in” and “out”. Photosynthesis is the “in-breath”, taking carbon dioxide out of the atmosphere and used to build biomass. The “outbreath” buts the carbon dioxide back into the atmosphere. The difference between the “in” and “out” breaths alters carbon dioxide in the atmosphere, and thus effects climate.
Scientists are actively studying the processes that control the sizes of the in and our breathsso they can predict how atmospheric carbon dioxide concentrations will changes as plant communities repond to altered climate conditions and as humans remove natural vegitation to buikd cities and grow food.
She discusses how the yearly see-saw pattern of the Keeling Curve provides an example of how the carbon dioxide concentrations fluctuate through the yearly seasonal cycle of vegetation growth and decomposition.
But much more can be understood about what controls seasonal carbon dioxide concentrations by looking below ground, to the roots of plants.