What do the meter diameter and DBH of trees mean? What do you mean?

The meter diameter is generally used to indicate the specifications of trees or seedlings, and the symbol is φ. Refers to the diameter of a tree or seedling from the ground to the trunk of one meter.

When measuring the diameter of the instrument, if the cross section is abnormal, a set of vertically intersecting data should be measured and the average of the maximum and minimum values should be taken.

DBH refers to the DBH of trees or seedlings. That is, the height of the trunk from the ground is equivalent to the diameter of the height of the chest of ordinary adults. There are different standards for DBH in the world. In China and most countries, the breast height is set at 1.3m above the ground. This standard height is a convenient height for ordinary adults to measure readings with a wheel ruler.

Extended data:

Measurement method of breast diameter

The basic tools for measuring DBH are a DBH ruler and a measuring rod with a height of1.3m. When measuring in the field, the staff should first lean the measuring rod against the tree to indicate the position of DBH. It should be noted that the placement method of the measuring pole depends on the slope of the ground and the shape of the tree. If the measured tree bifurcates at the breast height, it is necessary to measure two bifurcates and record them as two trees in the data table.

If the measured object has fallen but not died, a measuring rod should be placed at the root of the tree to measure the chest height in the same way as when the tree grows upright.

Whether a tree is dead or not should be judged by whether there are green leaves on it. Even if there are only 1 or 2 leaves on a tree, it should be measured as a living tree.

Baidu encyclopedia-mijing

Baidu encyclopedia -DBH