Monday, November 1, 2010

The Critical Zone - need I say more

This weeks Smith Lecturer is Suzanne Anderson from the University of Colorado, Boulder. Anderson's research uses field work to understand the mechanisms by which chemical and physical processes shape the Earth's surface and control chemical weathering and erosion. She will be focusing on the Critical Zone - a term that is coming into wide use to describe the layer of loose, heterogeneous material covering solid rock, and includes vegetation, the water table and water bodies. Within this zone a number of physical, chemical, and biological processes and reactions occur that impact mass and energy exchange necessary for biomass productivity, chemical recycling, and water storage. The concept of the Critical Zone unifies many complex biogeochemical and physical geologic processes in an attempt to create a numeric value from which predictions can be made. Why might this be important? You might want to make predictions based on the Critical Zone if you were interested in understanding how contaminants (heavy metals, radioactive material and other pollutents) might spread through the environment for example. This weeks reading is a review paper Anderson wrote for the magazine 'Elements'. This magazine is produced for a number of minerological and gechemical societies, with each issue exploring broad and current themes in the mineral sciences.


  1. This looks like a super interesting topic, with a ton of environmental impacts. The Intro of the Elements article and the first sub section ("Where in the Critical Zones Does Chemical Weathering Occur") were quite helpful in explaining the science behind Critical Zones. The graphic on the second page was also helpful to clarify how a Critical Zone works. After that the paper got far more dense and scientific, but I still felt like I got the just of the paper.

  2. I thought Anderson explained all of her material really well. I was unable to really see how all of this is relevant and why I should care about it. It seemed as though they were still trying to understand the differences between the south- and north-facing slopes. It's cool to see that she doesn't have everything figured out. It seems like Anderson is open to new ideas and possibilities; it seems like a lot of the speakers have been the opposite: dead-set on the fact that their research is correct.

    I found her information about the recent fire in Colorado very cool. It was crazy to see the picture of the hole in the ground where the tree used to be. I guess I've never considered how much space a tree and its roots take up.

  3. The fact that she is incorporating the fire into her research is very interesting. It was not something that initially was in the research but the effects of the fire would definitely make changes in the Critical Zone for this area.

  4. I agree with the others-that last bit about the wildfire gave some modern perspective.

    I think she presented her points very well. She presented the distinctions between results from the slope samples and addressed possible critiques. Erosion and weathering are much clearer to me now.