Section 6.4: Your Data

Outcomes

Students will:

  • Interpret the different types of graphs the Research Team will provide.

  • Examine their data and make meaning of their analysis.

  • Analyze how the constructed timeline connects to the scientific data obtained.

Key Terms

Waterfalled

See content or Module Glossary for definition

XRF Data

For convenience, you will receive an image of your XRF graph (similar to Figure 13) that already has the elements labelled for your sample. This graph is a summation of all of the line scans of your tree core. These graphs are a good tool to give you a general sense of all the elements present in your sample.

You will also be provided with a graph like Figure 14. This is a waterfall representation of all the XRF scans of every tree ring. Waterfalled means that the data is layered which allows you to look at differences in XRF scans as the years progress. The top XRF line is the oldest tree ring and the bottom is the newest.

Figure 13 shows an example graph of the summed XRF data from an entire tree core.
Figure 13 shows an example graph of the summed XRF data from an entire tree core.
Figure 14 shows an example graph of waterfalled XRF data of each tree ring in a tree core sample.
Figure 14 shows an example graph of waterfalled XRF data of each tree ring in a tree core sample.

Figure 15 shows another representation of how your XRF Line Scan graphs will look. Remember that an XRF Line Scan shows one element per line. For your convenience, we have separated each element into its own smaller line scan graph. The x-axis is the same for every graph, being the years of the tree rings. Note, however, that the y-axis scale is different for each graph. This is because each element fluoresces at a specific energy so although the peaks may look similar in size, they are actually at different scales. This means that you will have to consider the actual peak height and not just the shape of the graphs.

Since Figure 15 can make it difficult to compare the elements to one another, you will also receive the XRF Line Scan data on a single plot, such as in Figure 16. This graph is just another way of presenting your data and might give you more insight to elemental changes between elements5

Figure 15 shows an example graph of XRF Line Scan data separated by element. The graphs you will receive will include more elements (this image was cropped).
Figure 15 shows an example graph of XRF Line Scan data separated by element. The graphs you will receive will include more elements (this image was cropped).
Figure 16 shows an example graph of XRF Line Scan data on the same plot.
Figure 16 shows an example graph of XRF Line Scan data on the same plot.

How Does the Provided Timeline Fit In?

The timeline that was compiled and sent off to our labs will be used to give context for any trends discovered in the dendrochronological or XRF data. For example, suppose the dendrochronological data shows a consistently below average growth rate after the year 1995, and/or perhaps the XRF data shows a rise in the copper abundance after 1995. We would look into your timeline around 1995 to see if any major events happened, such as the opening of a new smelting facility, a forestry fire, or a new disease impacts the trembling aspen trees. Your timeline will be used to help the Research Team and yourselves to understand the change in environmental conditions specific to your location.

What Does this All Mean?

Scientists get data from experiments all the time. However, it is not about reading the graph that is the important part. It is about interpreting the data which means to take information that the graphs give you and figuring out what kind of story your samples tell. It is important to know that all data is good data as each set tells an unique story for that sample.

There are some common questions that get asked when interpreting data. Use them as a guide when examining your own data. These are all examples of general questions that scientists would ask themselves about their own experiments.

  • Are the results what you expected?

  • Is there anything out of the ordinary about your results?

  • What do your results tell you about your tree?

  • Are there any relationships in the data?

  • Are there any connections between the timeline and XRF data?

  • What new questions do your data make you think about?

  • Are there any correlations to your data and data from other schools?

Lesson Ideas

Now that you have received your TREE data, what do you do with it? Build on this data, explore different concepts, create cross-curricular connections, and explore! We will be updating this section so stay tuned!

We thank you for your participation in the TREE program! If you have any feedback for us, please fill out our Feedback Forms or email the CLS Education Team!

Additional Resources

  • CLS Education Lessons and Resources: https://sites.google.com/lightsource.ca/virtualclassroom/home
    Check out the Lessons and Resources page on the CLS Education Virtual Classroom. We have lots of lesson and activities that connect to a variety of different subjects and skills that may help spark some inspiration for when it comes to implementing this data into your classroom. We would be really interested in hearing any feedback you have on any of these resources and especially on how you used the resources and data from the TREE program!