Abstract. The Atlantic Forest in southern Brazil has been subject to overexploitation in the past prompting the formulation of a rigorous conservation orientated policy by the government including a strict ban of timber harvesting. In the region, the forestland is mostly owned by farmers. The economic value of the forest is rather limited for those farmers, because of the prohibition of commercial timber harvesting as a source of income. Sustainable forest management systems can offer great potential as new income opportunities for land holders, and further actively support the process of ecosystem rehabilitation and protection of these ecosystems. Yet, successful implementation of such sustainable management systems requires feasible and adapted timber harvesting systems. In order to develop such harvesting systems, a regional comparative case study was conducted at a typical smallholder forestry venture with the objective to analyze and evaluate harvesting methods supporting sustainable management of the Atlantic Forest. This study assessed production rates and associated costs of a common conventional timber harvesting method (CM) and a proposed alternative method (AM). CM was performed by a selected, typical forest landowner who had only basic training in chainsaw operations, but 20 years of experience at the wood yard of his small sawmill. In contrast, AM employed a professional chainsaw operator from the Amazon forest, trained and experienced in reduced impact logging techniques using state of the art equipment, supplemented by a snatch block and a skidding cone for improved extraction. Time study based models identified tree volume, winching distance and skidding distance to landing as the most significant independent variables affecting productivity. Total net productivity ranged from 4.9 m³ PMH 0 -1 for CM to 3.1 m³ PMH 0 -1 for AM. Corresponding gross-productivity ranged from 3.0 m³ SMH -1 to 1.9 m³ SMH -1 with an overall mean utilization rate of 60.8 % and 60.9 %, respectively for CM and AM. Associated harvesting costs ranged from 12.05 € m -3 to 20.94 € m -3 with an estimated annual production of 4000 m³ and 2700 m³, respectively. Although AM showed overall lower productivity and higher costs, it enabled important improvements in terms of occupational 204

Conservation and management of forest ecosystems are currently largely conflicting goals in the Brazilian Atlantic Forest biome. At present, all parts of the Atlantic Forest are protected and commercial logging is highly restricted. However, sustainable forest management systems can offer significant income opportunities for landholders, and thereby actively support the process of ecosystem rehabilitation and protection of the Atlantic Forest. This research is intended to contribute to enhancing the development of environmentally sound forest management alternatives in the Atlantic Forest biome. Through a case study, the harvesting impact of a conventional harvesting method (CM) was evaluated and compared with an alternative and improved harvesting method (AM), performed by a well-trained professional chainsaw operator experienced in reduced impact logging techniques, and included the use of a snatch block and a skidding cone. Following a full pre-harvest inventory, 110 different tree species were identified. The harvesting impact on the residual stand was classified and evaluated through a successive post-harvest inventory. Damage maps were developed based on interpolation of tree damage intensities with the triangular irregular networks (TIN) methodology. Our results showed noticeable high rates of tree hang-ups, observed for both harvesting methods. Furthermore, the harvesting damaged trees mainly in the lower diameter at breast height (DBH) classes. In comparison to winching, the felling process caused most of the damage to remnant trees for both methods, at 87% (CM) and 88% (AM). The number of damaged trees (above 11.9 cm DBH) per harvested tree, for CM, ranged from 0.8 trees to 2.5 trees and, for AM, ranged from 0.6 trees to 2.2 trees. Improvements of the AM method (operator skills, skidding cone and snatch block) over CM allowed for a reduction of the damaged basal area, a reduction of the “high damaged area” per plot, and a reduction of the winching disturbed ground area. Nonetheless, a suitable harvesting system should consider further improvements in the felling technique, and additionally integrate the local knowledge of CM regarding forest and tree species with the technical improvements of AM.

No abstract

This study aimed to technically evaluate loading and unloading with different wood lengths. Data used were obtained from log harvesting areas of a forestry company in southern Brazil, on operations with loblolly pine logs. The study addressed the analysis of time and motion, being divided into loading, unloading, mooring and unmooring. Four treatments with different log lengths, number of safety straps and number of sampled vehicles were analyzed. Analysis of variance and Tukey test were used to evaluate differences among treatments. Loading and unloading productivity increase of 114% and 92% was observed, respectively, when log length increased from 2.4 m to 7 m. When log length increased, productivity and yield of hours/work also increased. Loading was negatively influenced by the environment where the activity was carried out.

O presente trabalho teve como objetivo avaliar as operações de corte florestal do harvester 911.3 X3M em diferentes classes de declividade e sentidos de operação, bem como avaliar os movimentos nas distintas operações da máquina. Este harvester foi desenvolvido na Alemanha para atuar em declividades de até 40° e ainda não havia sido utilizado em plantações florestais no Brasil. Os resultados evidenciaram que a produtividade não decresceu com o aumento da declividade, assim como os diferentes sentidos de operação não influenciaram no volume de madeira colhido por hora.