The community composition of grassland regions are particularly sensitive to climatic changes due to the alternate photosynthetic types present in many of these systems. Much of the grasslands around the world are home to both C3 and C4 grasses, each of which evolved at different times in the Earth's history and thus have different requirements for resources such as CO2 and water and different temperature tolerances. The Free-Air CO2 Enrichment experiment, BioCON, which is housed at the Cedar Creek Ecosystem Science Reserve in Minnesota provides a long-term (26 years to date) study of how an array of C3 and C4 grasses respond to changes in atmospheric CO2 concentrations, nitrogen availability, water availability and temperature.

In this study postdoctoral researcher, Sarah Raubenheimer, is studying how changes in these factors influences the photosynthesis and growth of 4 species of C4 grass and 4 species of C3 grass, and how these responses influence competitive interactions. The outcomes of this study will provide important insight when predicting future community level changes in North American grassland systems. 

Researchers Involved