According to the latest studies regarding ecology, the Clear Air Act can really help the forest systems to recover from the damage done by acid rain and sulfur pollution. The researchers studied red cedar trees which had been affected by acidic pollution caused by sulfur dioxide emissions.
The specialists have been studying red cedar trees’ rings that are older than 100 years. They have found that the health of the trees has improved since the Clear Air Act passed back in 1970. They claim that there is a clear change in the growth of trees. They also add that there are two levels of interpretation of the study.
In order to reach their conclusions, the specialists gathered information regarding red cedar trees which are 100-500 years old. The main aim of the specialists was to understand the physiological response of trees when they are exposed to acid rain or acid deposition. In order to find out more about the effects of the environmental changes, the specialists studied the stable carbon isotopes within the tree rings that record the physiological changes in each time period. The researchers chose the beginnings of the 1900’s as the starting point of their study.
Why These Trees?
The specialists decided to study red cedar trees because they are a good recorder of the changes of the environment, they are abundant, and they live for long periods of time. These trees have a slow growth and they rely on the moisture that they can find on the surface, thus they are more sensitive to the changes in the environment.
Through studying the stable carbon isotopes, the researchers were able to compare the growth patterns of each of the rings and the changes in physiology can be linked to the environmental changes of the 20th century. The findings suggest that despite of the increase of the carbon dioxide levels that usually speed up the growth process of plants, the growth of the trees actually slowed down during the time when pollution was high.
When considering the findings of the research we have to consider the physiology of trees and the data gathered from the tree rings. On the other hand we also must remember the amazing impact that the act can have over the entire ecosystem.