Reduced Impact Logging and Regenerative Ecology of Lesser-Known Species in the Peruvian Amazon

PhD defence

Rune Juelsborg Karsten


Tropical forests are important for the local communities and for the international market demanding tropical timber as well as non-timber forest products. Tropical forests have also become a global concern due to accelerating deforestation and biodiversity loss. More recently tropical forests have been recognized for the ecosystem services that they provide and their role in mitigating climate change. While the notion of SFM remains controversial within academia, there is a broad accept of the concept. Third party certification bodies are verifying the sustainable origin of timber that follows the set of SFM guidelines. However, the actual impact of this type of logging is still poorly known and the long term sustainability of SFM remains in question. Tackling the question of long term sustainability would be too ambitious for a single PhD-thesis. This thesis instead investigates the prerequisite for long term sustainability: how does the forest regenerate following logging disturbance?  The thesis is composed of three articles. The first article of this thesis documents that the logging activities based on the current guidelines for a sustainable forest management, successfully mimics the natural processes of the ecosystem. The thesis also investigates the impact of the other major disturbance associated with logging: the establishment of skid trails, roads and log landings. The regeneration of timber species was found to be highest at the least disturbed sites, with a declining amount of regeneration with increasing levels of disturbance. The final part of the thesis investigates the timing of the phenological events, as an effect of climatic variation. The analysis showed that the determining factors for phenological events were the river level and average temperatures. The thesis illustrate that with the use of the best management guidelines for sustainable forestry, it is possible to mimic, to a large extent, the natural processes in the forest, thereby maintaining a productive biological system. The thesis is furthermore highlighting issues in the current guidelines that could be improved. Only by keeping the biological system intact, will the forest management ensure the long term sustainability.

Principal Supervisor

Associate Professor Henrik Meilby, Department of Food and Resource Economics, University of Copenhagen.

Assessment Committee

Senior Advisor Anders Ræbild, Department of Geosciences and Natural Resource Management, University of Copenhagen (chairman);

Senior Lecturer Morag A. McDonald, Ecology and Catchment Management, Bangor University, UK;

Team Leader of the research unit “Goods and Services of Tropical Forests” Plinio Sist, Cirad, Montpellier, France.