Methods of estimation of height of trees in Semideciduous Seasonal Forest

Abstract

Abstract

The research was conducted in Forest of Rosal, Guaçuí-ES, in order to evaluate accuracy and running time of five  height estimating methods in different ground conditions; the methods are as follow: Vertex hypsometer (1); Digital Clinometer (2), estimation with aid of a 15 meters ruler (3), and visual estimation with training (4) and untrained (5) in three height classes: 1 (15.00 - 17.99 m), 2 (18.00 - 20.99 m), and 3 (>21.00 m). It were measured 124 individuals in flat ground and 87 individuals in sloping ground. The height data were compared by t test and residual graphic analysis and additional statistics. To evaluate time, it was improved a t test. The method 5 had the worst performance in terms of accuracy, the best performance was improved by the method 4. The slop affected negatively the digital equipment performance and favored the method 3. There was a tendency to underestimate height as classes increase. The methods 4 and 5 consumed less time and method 3 consumed the highest average time. The class effect on average time on flat ground was the same for all methods but method 2. On slope ground, performance of methods 3 and 4 weren’t altered.

Keywords: Height; accuracy; time.