Lichen Proliferation in Fire Damaged Areas, a Study in Organism Replacement vs. Displacement in Desert Ecology
Mitchell, K.
Wolfenstein, O.
Talbott-Carey, S.
Stone, M.
Abstract
We studied whether lichen would be more prolific directly after a fire, or long after a fire. Our study surveyed three sites of varying time elapsed between the last fire it had experienced and the present. We found that the sites which had more recently experienced fires had less proliferation than those which had had more time to regrow. This showed that regrowth time was a more significant factor than risk of displacement by other organisms in lichen’s proliferation.
Introduction
The study of lichen in a desert environment recovering after a forest fire is a question of replacement vs. displacement. Lichen is a slow growing organism and so it’s replacement rate is very low. Consequentially, it would take a long time for lichen growth to appear after an ecological disaster such as a fire. On the other hand, lichen is one of the first photosynthetic organisms that can inhabit an environment after a fire. So there is also the question of displacement; once other organisms become capable of inhabiting the environment, they may displace the lichen. Therefore, it is unclear whether lichen would be more prolific immediately after, or long after, a fire. This study seeks to answer that question.
Methodology
We surveyed three sites. One of which had experienced a fire within the past 25 years, one within the past 120 years, and the last had not experienced a fire for over 200 years. We randomly selected habitable environments, namely rocks, for lichen at each of these sites, and using visual analysis, ascertained the amount of coverage the lichen had in these environments.
Results
Our surveys found that the site which had not experienced a fire in the past 200 years to have significant lichen proliferation. The site that had experienced a fire 120 years ago had less, but still significant, proliferation. However, the site which had very recently experienced a fire had little to no lichen present.
Conclusions
Our study found that in desert ecologies, lichen’s slow replacement rate was a more significant factor in it’s proliferation after a fire than it’s risk of displacement by other organisms. This has important repercussions in the study of biome recovery in desert ecology after a significant natural disaster.