1. Water and Isotopes in Central Kenya Katherine Zhao

2. Caylor Ecohydrology Lab Mpala Research Center, Nanyuki, Kenya

3. How stomatal conductance and photosynthesis vary with leaf age How Acacia mellifera responds to changes in water in the environment Measuring stable isotopes to determine the source of the leaf’s transpired water

4. Methods Li-6400 Portable Photosynthesis System Porometer to measure stomatal conductance Isotope analysis chamber Pressure chamber Taking measurements throughout the entire day Analyzing differences in transpiration and photosynthesis in old and new leaves

7. Results Diurnal pattern of transpiration Old leaves were more resistant than new leaves to water loss

9. Advisers Kelly Caylor, Associate Professor, Civil and Environmental Engineering Hilary Wayland, Ph.D. candidate, Civil and Environmental Engineering