Monitoring of harvesting and regeneration state of a Nothofagus pumilio forestry management plan located near the forest-steppe border in Tierra del Fuego, Argentina

Abstract

The study located in Tierra del Fuego, near the forest-steppe border, contains 1,400 hectares of Nothofagus pumilio forest, harvested in more than 90% of the area, starting over ten years ago. Different alternatives of the shelterwood system method were applied in most of the area. The objective was to evaluate the regeneration of the forest and their significance for the future forest harvest in the ecotono area. The forest area was stratified in a GIS according to harvest intensity. Terrain survey plots were made in each category. Forest and environmental parameters were measured with emphasis in regeneration density and quality. Several problems related to regeneration density, quality and distribution were detected. In more than the 70% of the area, regeneration was completely browsed by herbivores. Presence of cattle and guanaco was detected though the effect of both herbivores was impossible to be distinguished. The regeneration layout followed a grouped pattern, located in sheltered places, protected by scarce harvesting waste. In most of the area, the recruitment of seedlings was insufficient for the complete recovery of the forest canopy. The harvested forest floor has been completely covered by exotic herbaceous plants, especially graminea. The forest canopy cover resulted scarce to fulfill its protecting function in most of the area. It is unlikely that the forest will recover the productive potential that it had before harvesting. Half of the harvested area is in risk of degradation into non forest successional stage.