Processos e equipamentos como soluções inovadoras na operação de desrama em Tectona grandis L. f.

Abstract

Teak (Tectona grandis L.f.) is one of the most valuable tropical hardwood species on the global timber market. The management of plantations requires silvicultural treatments throughout the growth period, with emphasis on pruning. Currently, forest pruning has low quality and productivity, impacting the health of the plantations. Therefore, this dissertation has the general objective of promoting the innovation of processes and equipment used in the pruning operation of Tectona grandis L. f. To achieve this objective, the study was divided into four chapters: In chapter 1, the objective was to evaluate the in vitro effectiveness of fungicides and sanitizers from the mycelial growth of three fungi isolated from Ceratocystis fimbriata. In the first test, mycelium discs were immersed in sanitizing solutions for 30, 60 and 90 seconds. As a result, hot water (80ºC) and Vet20+® were the treatments that had 100% inhibition at all times tested for all isolates. The second trial tested different fungicides at different concentrations of active ingredient. The mycelial growth of the colonies was evaluated, and the fungicidal or fungistatic activity of the products was obtained. As a result, Ridomil Gold MZ® inhibited 100% at doses above 250 mg dm-³, and in addition, it showed fungicidal activity. Chapter 2 and chapter 3 bring analyzes of the productive performance and costs associated with pruning at different heights, in 2-year-old stands (operation up to 2,10 meters), and 6-year-old stands (operations up to 3,70, and 5,70 meters) comparing tools and equipment currently used, Tramontina® Handsaw, Stihl® KM85R Power Cutter, Stihl® HTA85 Electric Power Cutter, in relation to the innovative equipment, INFACO® F3015 Electric Scissor. As a complement to the analyses, the influence of the pruning system used in relation to the epicormic branch growth after the operation is provided in the 2-year-old stands. As a result, productivity with at electric scissor is 19% higher on average, greater operational efficiency, on average 6%, and lower production cost per acre, equivalent to 13% in relation to the use of the handsaw at 2,10 meters operation height. In the 3,70 meters activity, the average productivity with the scissors was 32% lower, with costs per acre 37% higher for one of the areas. The activity with electric scissor also showed the highest operational efficiency (4%). In the 5,70 meters activity, the average productivity with the scissor was similar, with production costs per acre 6% lower, however, as there are branches in which the electric scissor does not cut because it exceeds the maximum cutting diameter and there is a loss of the desired height due the rod length, is not operationally viable for that area profile. As for the diagnosis of epicormic branch growth, the first area presented three growth patterns according to the genetic material present, and the second area, presented an average of 67.4% of regrowth in the pruned cuts, regardless of the pruning system. Chapter 4 proposed operation productivity prediction models with data and parameters originating from performance analysis, in addition to a micro-planning model of the operation based on the spatialization of the studied areas. The results showed that the models could be designed by area or grouped by operating age, and that factors such as operators, equipment and number of branches per diameter class are influential in productivity.