I enjoyed this chapter.
The first thing that struck me was on page 46 in the point on anaerobic and aerobic bacteria. It states that E.coli are facultative anaerobes, which means that they are anaerobic, but can hack it if things go aerobic. This makes me wonder, then, how we can keep it out of our composts if we use manure. If aeration doesn't get rid of them, does the high heat?
I was really excited to finally understand nitrogen fixation! The details of this subject have always been a bit cloudy for me. I was surprised to learn that out of the 4 types of bacteria that take nitrogen that is a plant-inaccessible form and turn it into a plant accessible form, only 1 is the kind in legumes (oh, and I did remember noticing the root-nodules when I pulled the plans a few weeks ago
). We so often hear about nitrogen fixation through beans,etc., that it is virtually the only form we think of when we hear the term. This article seems to indicate that there is also plenty of fixation going on from the other 3 types nitrogen-fixing bacteria that are just in the soil. Someone please correct me if I'm off on this one.
It was interesting to me that anaerobic bacteria produce compounds (alcohols) that are toxic to plants. However, it shouldn't surprise me when I think about some of the bacterial diseases that we see mentioned with different crops. It also makes perfect sense that there are only so many soil pore and so much rhizoshpere that bacteria can inhabit. It is easy to see how, if we keep our soils in aerobic conditions that favor the growth of beneficial bacterial populations and that harmful bacteria can't even survive, beneficial bacteria populations can really diminish harmful one.
On the subject of the soap, I remember an article I read not too long ago where the author questioned the persistent use of antibacterial soaps, arguing that they are also killing the beneficial bacteria on our skin, as well.
HG, it looks like all of our improper disposal of antibiotics and other microbial-resistant compounds, like microban, are encouraging our friendly soil bacteria to become potentially health-threatening.
However, to be fair, I'm sure there are cases when the occasional squirt of Purel does more good than harm. Cases like visiting a sick friend at home or in the hospital, where some particularly nasty microbes may be lurking.