Using a Dendrometer and Other Information

Hello Sabercats,

Today I went back out to measure and tag more trees with Loren Chasse, Stacey Cahn, Jackie Scherer, and scientist Jeff Lombardo. Jeff showed us how the dendrometer can be used to determine how much the trees that we tag grow. We did not install any dendrometers yet.

Several of you have offered some terrific questions and I have done my best to find answers or resources we can consult to find the answers.

Many of you have asked about UVb radiation and why it might be important to collect this data to know more about the aquatic ecosystem in Chesapeake Bay. Visit UV Effects on the Aquatic Environments page to learn more about how UVb affects the organisms in this environment. After reading just the first paragraph of this page it appears that plankton may be affected negatively by increased UV radiation and have reduced photosynthesis when UVb is high. What do you think? Why might this be important to monitor in an aquatic ecosystem.

I also had the opportunity to speak with Dr. Jess Parker about the Ultraviolet radiation in the forest and he shared that the plants do respond to the UV. The leaves at the top of the trees recieving the most UV radiation contain different pigments that help to protect the tree. The leaves on lower branches of the same tree do not contain these same protective pigments.

A couple of you asked how long it takes for a tree to decompose and leave only a mound from the "pits and mounds" post. Jeff and Nancy agreed that it would probably take at least 50 years for the large trees to decompose to this point. However, there are factors such as the type of tree, its size, weather conditions, and where in the forest the tree is would all affect the rate at which the tree would decompose.

Zach M. asked about the data that has already been collected at SERC and how that data has contributed to what we understand today to be happening to our climate. Changes in CO2 has been recorded here for 30 years and differences in the concentration of CO2 in the atmosphere has been detected. The study we are participating in is looking at biomass changes and has tracked the growth of 10,000 square meter plot for the last 13 years. Take a look at Dr. Jess Parker's research at the Forest Ecology Lab Publications or the Forest Growth and Global Carbon Cycle page. Dr. Parker also reminded us that the work that we are doing this week will create the structure for ongoing data collection about the biomass of this forest and how carbon is being cycled here. Hopefully, during your presentations with Janis Slater and Deborah Dalton you discussed that CO2 can be sequestered in forests which is important for keeping the atmospheric CO2 levels down.

This afternoon I also asked Dr. Parker about the rainwater collection, including why the samples have to be collected and analyzed so quickly and what chemicals they are looking for in the samples. He shared that it is important to evaluate what is in the rainwater quickly and carefully because it is mostly water and anything that contaminates the sample seriously changes its composition. The rainwater could possibly have about six really important ions it: sodium, calcium, magnesium, ammonium, hydrogen, sulfate, and nitrate. Sulfate and nitrate are important because they are by products of human activities. Sulfate ions are produced from burning coal and nitrate is produced from the incomplete combustion of fuel in cars. The pH of the rainwater is one of the very first things that must be measured because it can change quickly.

You guys have had some really super questions. This has been really terrific!