Molly Brown’s Diary
Climate Change, Canopies and Wildlife in the Ecuadorian Andes

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September 29, 2009: Transpiration and Precipitation

I am working with Matt and James on the precipitation and transpiration study today. We are taking leaves from trees in the forest and studying how quickly they transpire (lose water vapor from a plant's surface. To accomplish this we have to put the leaves in a bucket of water with a plastic tube and a glass tube. The idea is to get the leaf in one end of the plastic tube and the glass tube in the other end of the plastic tube without getting any bubbles in the two tubes. Then the whole thing gets put in a meter that measures how long it takes 10 cm of water to transpire. It is so hard to get the leaves in the meters without any bubbles in the tubes. We eventually start holding the leaf and tubes under water and using Vaseline to clog the holes. Of course then getting them out of the water and into the meters without dropping them became another issue because of our greasy hands. So once we conquered all of those issues and had the leaf in the meter we would take a light reading, record the start time, and the finish time. After the leaf was finished transpiring we took a tracing of the leaf and noted any damage. We also put the percentage of damage to the leaf on the paper. We managed to get 6 sets of leaves done all day. In the downtime we are just talking about British vs. U.S. culture. After lunch the clouds rolled in and our study really slowed down. We spent the rest of the afternoon watching two leaves because it was taking so long for them to transpire. The presentation after dinner was about camera traps in the reserve. Xavier heads up that program and showed us some great photos of Pumas, Spectacled Bears, and other animals.

Click image to enlarge.