After more than a month I finally have a new story. That I didn’t write anything was absolutely not because it was a boring and not interesting period to write about, no it was a very exciting month. In this month, I came a lot further in my research. Especially because the last month was the month in which I finished my compost (just in time :) ) and started with doing my plant experiments. Besides that, I also started teaching how to make compost in another school in the countryside. The best part of this school is that I am doing that with 6 out of 9 classes, so it is basically a whole school is busy with making organic fertilizer.
Already two weeks ago (time is going so fast), I experienced that inorganic fertilizers/ pesticides/ herbicides can have quite a negative impact on the soil. I went with my supervisor, Esperanza, and three other students to the farms of some Mennonites in the neighbourhood of Dzibalchén to take soil samples for a future study Esperanza is going to do. We took these samples in monocultures of soya, as you can see on the picture. Some of the monocultures were upgraded with some sort of irrigation (on the picture you can see a sprinkler system), which is of course very interesting for a biller (bachelor student international land and water management), but that was not the reason for our visit. The reason why we came there is that we had to take soil samples at different depths for analysing pesticides and heavy metal contents. Besides that, we had to search in the samples for soil fauna.
At the moment I cannot say anything about the impacts of the inorganic additives on the chemical soil quality, because it has not been analysed yet. However, the soil fauna alone, or actually the absence of fauna told us enough about the soil quality. An indicator is for example the amount of earthworms we encountered. Esperanza told me that in a forest floor (thus not a monoculture) you would normally encounter 20 earthworms in the volume of one sample. In the fields of the Mennonites we took 25 samples and we found 2 earthworms. That means that there are on average 0.08 earthworms in one sample. I knew that the use of monocultures and a lot of pesticides could have a negative impact on soil life, but that we would encounter so little (also other soil life was almost not present in the fields) I really didn’t expect and made me think about it of course!