This week, the guest at the Rose Cafe was Dr. Dawit Solomon, and he came to speak with us about soil.  My basic understanding of soil before this talk was somewhat comprehensive: I knew it was eroded rocks, gradually broken down over time, with the additions of nutrients.  Soil is what provides life for most plants.  This was the definition we saw at the beginning of the talk when Dr. Solomon introduced us to the topic of soil.

Soil formation is a lot of weathering of rocks, from wind and water and other sources, and soil will end up different based on how it was formed.  The nutrients found in it, how it is layered, even the coloration all depends on how it was formed.  I thought this was very interesting, having not really put much thought into the different colors of soil before.  But soil delivers lots of ecosystems services that enable life all over the Earth.

One thing that surprised me was how much soil has to do with global warming.  I didn’t know before this talk that soil could hold carbon in it, rather than having it being released into the air as yet more CO2 harming the atmosphere.  Soil has the potential to become a carbon “sink” but right now, soil and land degradation is making that less possible.  There is a certain amount of carbon on the Earth, and while there is currently a lot of it in the atmosphere, it could be stored in the soil instead, which would in turn provide better soil for plants and animals.

Another topic Dr. Solomon discussed was things we could learn from indigenous communities.  They have been using the soil without technology for a long time, and from them we can learn more about fertilizers to help the soil stay good.  Overall this talk was very interesting.  I didn’t think much about soil before, but I’m sure I will think more about it now!