External surface growth rings
(annuli) or checks and internal growth lines representing a gastropod's age occur because of changes in seasonal shell growth rates that cause a change in the appearance in the shell as a result of variations in the inorganic/organic content and the shell crystal structure.
To achieve the goal, a system approach linked the results from previous studies (Jeong and Zink-Sharp 2012, 2013; Jeong 2013) that encompassed the information of anatomical structure from different forest managed trees associated with height and growth ring
numbers to OSB mechanical properties of the current study.
The number of the growth rings
on each scale was verified by three different people and the final results comprised the number of the most frequent growth rings
Schematic view of a section of two growth rings
. Early wood--or spring wood--contains more and larger vessels.
The lumen diameter (DL) presented high variability between growth rings
. This could be related to the decrease of growth rings
due to increased age of the wood and, consequently, a higher proportion of early wood than latewood.
were distinct and ring boundaries marked by one (usually) or more lines of wide vessels and banded parenchyma.
Although differences are low, in general ,specimens with narrowest rings and low density were more decayed than specimen with average or the widest xylem growth rings
. The highest mass losses were observed at specimens with narrow rings (table 1).
In most trees, a single annual growing season results in the formation of a growth ring
. These rings are xylem tissues, and as the tree ages, the inner (earliest) rings usually accumulate metabolic by-products and take on a different appearance.
The MIR analysis conducted for sailfish suggested that one growth ring
is formed each year from September to November for males and from October to November for females.
This reaction zone forms from the cambium along the edge of the outermost growth ring
present at the time the tree was injured.
Age as determined by the external growth ring
method was about half that estimated by the internal shell layer method or the ligament method.