Drawing Conclusions
Interpreting the Data
The consistently higher quantity of fungal fruiting bodies in the area further from human development seems like a note of confirmation that human influence between the populated and developed area and the area observed further from town. Yet the similarities in pH levels could indicate that soil quality is consistent over that distance. There are far too many uncontrolled variables in this collection of data, however, to make a genuine conclusion.
To look at the soil pH alone, the consistency between the locations still may not mean a healthy habitat in between, though the soil in both locations has pH that is healthy for fungal growth. Specifically fungi that are mycorrhizal in nature (that is, having a mycelium below the ground with which it connects to trees being able to exchange, deliver, or steal nutrients) or those that are saprotrophic (that is, those fungi whose relationship with the soil is as a decomposer, both decomposing leaf and other ground detritus and dead wood or dead parts of live trees) are beneficial to the quality of soil by unlocking nutrients that benefit plant growth, as mentioned in the introduction. In addition-
“One of the most influential factors affecting the microbial community in soil is pH. pH strongly influences abiotic factors, such as carbon availability (4, 42), nutrient availability (1, 41, 42), and the solubility of metals (24, 25). In addition, soil pH may control biotic factors, such as the biomass composition of fungi and bacteria (23), in both forest (12, 17, 28) and agricultural (6, 15) soils.” (Bååth, et. al)
The effect of pH in soil directly affects the nutritional availability, and the quantity of fungi growing within. Yet within other experiments, it can be shown that fungi are able to affect the pH of soil to the pH that they best thrive in- “These authors mention that as opposed to organisms able to control their internal conditions, microorganisms maintain their pH-redox homeostasis by modifying the environment where they live.” (Bousset et. al) While fungi are breaking down detritus on the soil to base nutrients, they may also be changing the pH of the soil and thereby affecting the factors written about by Bååth.
A. Example of a saprotrophic (decaying) fungi, decaying leaf litter. B. Example of mycorrhzial fungi in a mutualistic relationship with a nearby tree. C. Saprotrophic fungi decaying dead wood. D. Parasitic fungi stealing nutrients from the tree it grows on.
It is definitive that the presence of fungi is beneficial to soil health, but can this be said exclusively for the presence of fruiting bodies? Mycorrhiza form fruiting bodies typically based on season. Some may fruit only in fall, some may twice a year, and some may fruit from early spring until early winter. The diversity in fruiting season would require this observation process to be conducted over the course of a full year to use fruiting bodies as an indicator. Of course, the mycorrhiza can only fruit when there are enough nutrients available to provide that much growth. Like many other species, if the base health is not at an acceptable level, reproduction may be halted.
We may not have found any spectacular specimen like the picture above, but the data we collected has opened up new questions and ideas for further research.