Table of contents:
- A brief history of dendrochronology
- Dendrochronology methods. Instructions for use
- What does the dendrochronological examination say?
Each ring of the tree is unique, as its width depends on how rainy the year was when the ring was formed. This is the dendrochronological research method based on the study of such annual rings. By comparing fingerprint databases of trees growing in different parts of the world, we can get a glimpse of the climate of the past.
A brief history of dendrochronology
Dendrochronology is a field of science that was born a little over a century ago. But despite her youth, she almost immediately was able to help in the study of various kinds of biological changes over the past thousand years.
However, it appeared even earlier, when the foresters had to determine whether it makes sense to cut down the tree or if it still gives growth - the annual rings in the drilled trunk were responsible for whether it would still hold on to the roots or not. This uncomplicated dendrochronological dating method subsequently developed into an independent science.
It happened when the term "dendrochronology" was suggested to be used by the physicist Andrew Douglas. As director of the University of Arizona Observatory, he studied changes in solar activity and noticed that trees have the same frequency of changes in their growth, similar to the frequency of solar activity.
Douglas began collecting a base of tree rings growing from the mid-15th century. He then began researching an even more ancient source of data - wooden beams from the ruins of Puebloan in the southwestern United States. This is how dendrochronology appeared.
Dendrochronology methods began to be widely used at the junction of other sciences in the second half of the 20th century. This was facilitated by technical development and the progress of human views in general.
Dendrochronology methods. Instructions for use
Why did Douglas start collecting trees with almost five centuries of history in his collection? The fact is that tree rings can tell a lot about the solar cycles of the past and how they influenced the Earth's climate. Consequently, using the dendrochronological method, one can find out the temperature regime of a particular area over several millennia. And over the years!
This is an excellent aid to the radiocarbon dating method, therefore, perhaps, dendrochronology is not used more often than in archeology. The rings clearly show how the natural environment has changed and who was the factor behind these changes.
During the initial examination, be sure to pay attention to the following factors:
- the size of the wood cells;
- cell wall thickness;
- maximum wood density;
- damage to wood, including specific
All this allows you to collect the most complete picture from which you can start a full-fledged dendrochronological examination.
What does the dendrochronological examination say?
In addition to dryness or, conversely, too rainy periods during the time of the area, as well as the exact time in the past, dendrochronology allows you to learn several interesting phenomena that enrich the climatic history of our planet.
Thus, dendrochronological analysis made it possible to determine that the accident at the Chernobyl nuclear power plant in 1986 left its mark in the strangely aligned rings of the surviving pine trees. The designs on the violin by Antonio Stradivari, worth about $ 20 million, speak not only of the age of the violin itself, but also of the geographical origin of the wood from which it is made.
Perhaps you should treat trees a little differently, because behind them, in the literal sense of the word, history is hidden.