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How is the age of the tree calculated? What are the tree rings telling us?

The connection between the annual rings of timber and local weather

Most of us have seen intertwined round rings on a reduce tree trunk. How many of us are conscious of the undeniable fact that these rings present us with necessary info? Current studies have shown that the improvement of tree rings is associated to climate elements.

The presence of tree rings is intently associated to the seasons. In tropics the place the climate doesn’t show seasonal differences, the timber have a progress function all through the yr. Subsequently, the rings in these timber are not apparent. On the different hand, in the northern hemisphere the place seasonal variations exist, progress is not steady, accelerated with spring, summer time begins to lower, and in winter it stops utterly. As in all crops, progress in timber also features momentum when soil water begins to be taken. This is the event referred to as ır water walking to the timber ır amongst the individuals.
In reality, progress is primarily a outcome of highly complicated physiological and biochemical events that depend upon water and temperature. Quicker progress means more water consumption. In the woody crops and timber, the water taken from the soil is transferred to the leaves where they are used, by means of the parts referred to as the wood tissues (xylem).
These are the parts that are shaped between the bark and the wooden, referred to as the cambium, in the direction of the inside.

Wooden texture, which occurs throughout the spring season when the water requirement is high, has a skinny wall and a large cavity. On the other hand, in the summer time, when progress is slowed down and the water requirement decreases, they have a thick wall and a slender gap. Subsequently, the wood shaped in the spring on a felled tree trunk is light-colored and in the summer time the wood is seen as darkish circles. On this case, a light-weight and a darkish ring correspond to an annual progress. The quantity of rings generally known as annual rings provides the age of the tree. But the info introduced by the rings is not restricted to the age of the tree. This is as a consequence of the proven fact that the courting of the archaeological stays, particularly the willpower of the fee of erosion and sedimentation in the last yr, the verification of the ages decided by radioactive carbon, the understanding of the historical past of vital forest damages or fires, the emergence of local weather modifications in the previous, and provide very enlightening info.

It is commonly known as dendrochronology or xylocronology (Greek dendro = tree. Xylo = wood) which tries to determine all these past occasions with the assist of annual progress rings. Dendrochronology is the only part of dendrochronology that offers with past local weather modifications. Dendroclimatology is gaining extra significance these days, especially when aggravated environmental problems convey up climate change.

Numerous findings present that the local weather is not constant and is continuously altering during geological durations. For example, in the last 2.5 million years, the northern hemisphere has been invaded by glaciers four occasions. Between the glacial durations, there have been interglacial durations characterized by the warming of the climate. The final glacial period ended 10000 years ago. In line with the widespread view, we are now in an interglacial period and our hemisphere is shifting in the direction of a glacial period. That is, the climate naturally tends to cool down.
On the different hand, there are some opinions that many environmental problems will cause warming in the local weather, especially in the greenhouse effect brought on by growing CO2, and that many places might be flooded by melting of collected ice in the polar areas. The advocates of this view, particularly in the last quarter century, present the end result of dryness consequently.

Undoubtedly, it is attainable to know the extent to which these views are justified, and first of all, to know the current modifications in climate. These modifications symbolize meteorological knowledge based mostly on greatest numerical measurements. Nevertheless, these knowledge are not adequate to allow the monitoring of the long-term course of the climate. Although the thermometer was discovered in the 1590s and the barometer was found in 1654, the standardization of these and the improvement of healthy meteorological networks have been only attainable in XIX. The second half of the century. Consequently, we have now already started to receive wholesome meteorological knowledge. Actually, meteorological knowledge belong solely to the last 150 years. This, of course, is inadequate to determine long-term climate change.

Scientists on this case, lakes mud and so on. they tried to take advantage of many knowledge from sediments to glaciers. By evaluating all these knowledge, it was potential to reveal the climate of the final millennium in a comparatively detailed manner. Accordingly, throughout this period, we will say that dönem small glacial cycles imiz and the extraordinarily dry durations are seen. The truth is, in the history of Herodotus all the video games besides the backgammon was found by the songs, the function of this, by forgetting the time of consuming the time to overlook the results of the drought as a consequence of long-term drought famine supports this view.
At the starting of the knowledge displaying the local weather modifications in the past durations, the annual rings of the timber are coming. The width of the annual rings is usually decreased in proportion to the age. Deviations from the normal curve are principally related to local weather. Ring width is primarily beneath the influence of rainfall, temperature and lightweight elements. Usually, rainfall in arid areas, temperature is the figuring out think about chilly regions. It has additionally been found that ring-wide sunspots additionally play an essential position.
The first research on the topic have been carried out on the coniferous timber grown in the mountainous half of California in Okay. America. Based mostly on the measurement of annual ring widths only, the climate modifications of the last 800-year period have been elaborated. In the temperate zone during which our country is included, the width of the population varies barely from one yr to the next. Subsequently, it is very troublesome to find out the fluctuations in the local weather by measuring only the ring width. In this case, kalınlık wood density ı, which is defined as the ratio of wood pipes to wall thicknesses, is considered. This technique is a healthier technique which may even show monthly modifications compared to ring width. As a matter of reality, high success rates of 95% have been achieved in research carried out with this technique.

Ring width in timber is beneath the influence of climatic parameters as well as other elements. Subsequently, so as to improve the reliability of the results, the quantity of samples must be multiplied and the elements outdoors the local weather must be eradicated.

Studies have shown that the greatest outcomes may be obtained from the higher and decrease forest boundaries. Because these limits are places where the sensitivity to climate in timber will increase. Extensive annual rings, each at the decrease and upper forest borders, are indicative of a damp heat climate. At the upper boundary, a slender ring at the decrease boundary displays scorching and dry circumstances, while the opposite is a outcome of cold and humid weather conditions. In both environments slender rings are indicative of each cool and arid climate.

Ring widths at the decrease boundary of the forest are largely dependent on moisture. The excessive rainfall in the spring and autumn right here leads to the formation of a large ring throughout the brief summer time interval. The excessive temperatures during these seasons scale back the moisture content of the soil and thus scale back the internet CO2 evaluation. Because of this there is much less food storage for the subsequent ring progress since there is a decrease in photosynthesis leading to the formation of wooden parts. Consequently, there is an inverse relationship between ring width and evapotranspiration. In different words, the summer time wood shaped in the regions the place the summer time drought is evident (for example, West and South Anatolia) is quite slender.

Dendroclimatological studies of pine, fir, cedar, spruce, and so forth. It provides extra constructive leads to coniferous timber. Nevertheless, since they are permanent green, the organic matter accumulation which causes the formation of wooden parts is lower resulting from the photosynthesis fee in previous leaves. On the different hand, the length of the leaves in the timber near the higher limit of the forest varies from yr to yr. The writing is a scorching interval, while extending the leaf size, whereas the leaves shaped throughout the cooler summer time months stay brief. As the photosynthesis occasion takes place virtually totally on the leaves, there is a direct relationship between leaf size and ring width. As a result of the letter will improve in scorching durations, leaf measurement will improve, the ring might be extensive. Nevertheless, this relationship is more than a period of 20-30 years.

Though it is all the time green, it is recognized that coniferous timber are additionally sleeping at very low temperatures. Subsequently, timber growing near the upper limit of the forest use a significant portion of the organic matter that they synthesize throughout the winter and subsequently the temperature regime of a given yr is efficient on the ring width of the similar or the subsequent yr.
On the other hand, hearth, insect injury and so forth. effects are also efficient on the improvement of tree rings. The timber parts that develop beneath regular circumstances as a everlasting circle can’t take the type of a circle as a result of the cambium texture doesn’t operate for several years in any impact. Thus, it is attainable to find out the yr when the hearth or insect pest is effective.

Normally, the ring is not troublesome to rely, but very often, resembling a magnifying glass and microscope instruments are used. Also, in these instances, the inclination of the trunk might help to watch the ring width. If this is not the case, it is crucial to wash the reduce floor with humus or paint with ink or indigo paints.
Nevertheless, the paint should immediately be slid after the software.

In lots of woods, the boundary between spring wooden and summer time wood is not clear. In such instances, the boundary can solely be determined by microscopic examination. If two layers of wall thickness of two adjoining wood pipes are equal to or greater than the area in the middle of one of the cells, this half is thought-about to be summer time wooden.

The very first thing that comes to mind is the sprucing of the minimize surface by means of a sandpaper. Nevertheless, in apply, annual rings might be decided with out this. A. Tree auger “is used for this function and a cylindrical rod is faraway from the setting to the middle. Then this rod might be divided into two elements in the longitudinal middle and it is attainable to examine the rings.

As is recognized, some timber can stay for a few years. 1000 or older timber are incessantly seen in our country. The dendroclimatological research to be carried out on these will have the ability to present very useful information about the long-term climate modifications in our nation.