Methodology of remote assessment of current growth by height in growing coniferous trees

Abstract

The increase in tree height over the past year shows the conditions for its growth. This indicator is called the current growth of the tree in height. Currently, to assess this indicator, tall trees have to be cut down. In order to increase the productivity by assessing this indicator, a method was developed for assessing the height of Scotch pine and Siberian spruce trees using materials from terrestrial digital photography. According to the proposed method, the current growth in tree height is photographed in the field using a telescopic lens. At the same time, the distance to it is measured using a laser range finder,. Then the measuring ruler is photographed at the same distance as before the current gain. In cameral conditions, the obtained images are compared on a computer and the current increase in height is measured. To determine the accuracy of measurements using the proposed method, the current growth in height was measured in 30 growing trees of Scots pine and Siberian spruce. The measurement was carried out using a measuring ruler fixed on a six-meter pole. The average size of growth in height was 64.6 cm for Scotch pine, and 50.7 cm for Siberian spruce. The analysis of the obtained results showed that the use of the proposed method made it possible to estimate the current height increments in Scots pine with a standard deviation of 4.03 cm, in Siberian spruce 3.58 cm. These data testify to the sufficient accuracy of assessing this taxation indicator using the proposed method. In addition, the developed method makes it possible to reduce the cost of assessing this taxation indicator.