tree ring analysis

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Tree ring analysis

Transcript of tree ring analysis

Tree ring analysis

Each year, the tree forms new cells, arranged in concentric circles called annual rings or annual growth rings. These annual rings show the amount of wood produced during one growing season .

A cross section of a tree shows much more than its age!

Diameter growth is particularly sensitive to fluctuations in the environment:

1. moisture in the soil and air2. temperature3. sunlight

Very broad rings generally indicate a good growing year.

Similar patterns occur in the rings of different tree species over a large geographic area due to variations in the amount of annual perception .

Years in which adequate precipitation occurs produce wider rings of growth , but years of drought produce much narrower rings .

The inner portion of a growth ring is formed early in the growing season, when growth is comparatively rapid (hence the wood is less dense) and is known as “early wood”.

The outer portion is the “late wood” (and has sometimes been termed “summer wood”, often being produced in the summer, though sometimes in the autumn) and is denser .

It is possible to study ring sequences that go back to several thousands years

1.master chronology:A complete sample of rings dating back as

far as possible .

The scientists to trees the first one which is old and the second older than the first and the rings of the center of the older tree are matched with those toward outside in the first tree

2.Dendrochronology : (dendron= tree, chronos = time) is a scientific

method that uses tree-ring sequences to date annual growth rings of plant to their exact year of formation. It is applied in several scientific fields, namely archaeology, climatology, geomorphology, glaciology, hydrology, fire history, entomology.

Dendrochronology it is the study of both visible and microscopic details of tree rings.

Uses :1 tree ring analysis has been extremly useful in

investigation of prehistoric sites of native Americans in the southeast

2.tree ring data are also useful in other disciptions including ecology to study changes in forest community over time

3. Environmental science to study the effects of air pollution on tree growth

4. ecology to date the earthquakes and volcanic eruptions

Studying the tree rings across several thousand years helps the researchers determine the natural pattern of global temperature fluctuations. They are not sure how much of the recent warming is the result if human influence rather than natural climate variability

Done by Mary Hijazin

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