Details

Autor(en) / Beteiligte

• Sales, Agust
• Antonio Siviero, Marco
• Cezar Gomes Pereira, Paulo
• Benmuyal Vieira, Sabrina
• Alves Berberian, Ghaby
• Maia Miranda, Bárbara

Titel

Estimation of the commercial height of trees with laser meter: a viable alternative for forest management in the Brazilian Amazon

Ist Teil von

• Ecology and evolution, 2020-04, Vol.10 (8), p.3578-3583

Ort / Verlag

England: John Wiley & Sons, Inc

Erscheinungsjahr

2020

Link zum Volltext

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• Commercial height of the tree is a key variable for estimating the wood stock in tropical forests managed for timber production purposes. Most available measurement devices suffer limitations in this type of forest, promoting low precision measurements with high variation errors. The laser meter device appears as a viable alternative, as in addition to using trigonometric principles, it is not necessary that the device is close to the eyes of the meter to carry out the measurement. The device can be used to measure commercial height of trees on flat or sloping terrain, at different distances from the tree. However, there are no studies evaluating the precision of this device. The objective of this study was to determine the precision of the laser meter method for estimating the commercial height of trees, as compared to the actual measurement in a tropical forest in the Brazilian Amazon. Measurements were made on 300 trees with commercial height between 7 and 14 m. Actual commercial heights were measured with graduated ruler. Applied tests were paired t test, graphical analysis of residuals and calculations of bias statistics, mean absolute deviation, standard deviation of differences, and coefficient of determination (R2). Paired t test indicated that the mean of the heights measured by the laser meter is statistically equal to that of the graduated ruler. Measurements with laser meter did not show bias and had mean error of 0.0745. The standard deviation of the differences indicated dispersion of errors of 0.97, equal to that shown in the graduated rule. Laser meter presents an alternative method for estimating the commercial height of trees in tropical forest in the Brazilian Amazon. There was no tendency to underestimate or overestimate the commercial heights of trees. Use of the laser meter is potentially of use for measuring the commercial height of trees in tropical forests. A new method and device to measure commercial height of trees in natural forests is proposed. The method has, besides practicality, good precision, and low cost, a great differential: The technician does not need to use the device close to the eyes. The technician observes the laser beam in the tree trunk and remains in the same position to realize the three measures necessary to obtain the commercial height. The device can be used to measure commercial height of trees on flat or sloping terrain from any distance from the tree.