I read Alex’s post and I wanted to reflect on his thoughts. I think it may be the case with most students in this class that this is their first in-depth science class other than general classes like biology, chemistry, environmental science, etc. That being said, I have really enjoyed this survey soils class.
Incorporating the various aspects of the other areas on science and focusing them on a specific topic is interesting. We studied soil physics with soil water, soil biology with plants, microorganisms and the Winogradsky column, and soil chemistry near the end with soil pH and cation exchange.
I think it was important also to study the conservation problems with soils and the future of soil. Soil loss is not something that any country needs to experience and like fresh water, once it escapes into the ocean, it can’t be reclaimed. At the beginning of the semester, we studied the impacts that soils have had on civilizations. Soil always is treated like a constant and stable feature to life, but in the future it may not be. With the use of some of the agricultural practices, it may be an indicator that some countries should regroup and reassess their natural resources. Urban Conservation was important, I thought, as well. I take more notice when passing a lot that is being developed or a plot of land with no silt fences.
Lab time was my favorite class period all week. Small class sizes with long jobs gave us some time to socialize and get to know each other. Since 7 of the 9 students in the class are the few and proud environmental science majors, it was nice to get acquainted.
I do have a couple things I wish we did more of. I wish we did more discussion out of the ‘Dirt’ book. Like I mentioned previously, I thought examining soil science through a historical perspective was new. I don’t think the topic would have lent itself to a whole class period of discussion, but its nice to accent some science with history. I am probably in the minority on this one, but I wish we did more sampling. I thought that taking the field trips and doing some hands-on learning was especially important.
As an aside, I do want to revise part of my last post. If you scroll down a couple posts back, I talked about changing the color of Hydrangea flowers. I wrote that it was not the pH that changed the color of the flowers, but the presence of aluminium. From lecture last Monday, we learned about cation exchange capacity and I saw that the opposite was true. With the higher Cation exchange capacity, more positive ions can be adsorbed, which affects the pH of the soil solution. So, the alumiunum cations through cation exchange capacity affects the pH, which does affect the color of hydrangea flowers!