Evaluation of Forest Harvesting Impacts on Forest Ecosystems

P. MAC DONAGH, O. GAUTO, L. LÓPEZ CRISTÓBAL, N. VERA, S. FIGUEREDO, R. FERNÁNDEZ, J. GARIBALDI, M. ALVEZ, H. KELLER, M. MAREK, J. CAVALIN AND S. KOBAYASHI

Rehabilitation of Degraded Tropical Forest Ecosystems

Center for International Forestry Research

Lugar: Bogor; Año: 2001; p. 69 - 80

In the Guarani preservation area 100 ha of forest land was cut to evaluate harvest impact innatural subtropical forest. Two treatments were applied: ?commercial logging? in which thelogging contractor works in the traditional way, and ?improved harvest? in which trees areselected and the skidding trails and landings planned. Forest structure and composition, seedlingsand regeneration; and soil physical parameters such as soil density, penetration resistance weremeasured before harvesting. The trees were cut by chainsaw and moved by a rubber tyredskidder to the landing area for loading on a truck. After harvesting, damage by cutting and byskidding was measured. All previous parameters were re-measured and traffic intensity ineach plot calculated. The harvest yields were 9.9 m3 ha-1 for the improved harvesting and 16.4m3 ha-1 for the commercial treatment. Trees felled were 6.8 trees ha-1 for improved harvest and9.9 trees ha-1 for the commercial harvest. For canopy trees, commercial harvesting reducedthe initial dominance 19.3%, while improved harvesting only decreased it 9.5% so forest structureis less affected by the improved harvesting. There was little change in abundance and speciescomposition. Changes were observed in the order of importance of some species, e.g.Parapiptademia rigida was replaced by species of lesser importance. Regeneration after thecommercial harvesting was less than in the improved harvesting method. Commercial harvestinghad more (60%) traffic intensity (Mg km-1 ha-1) along all the skid trials in the plots.