Carbon Loss (Tg C) from Logging 30 Year Integration, 15000 km 2 y -1 Slow decayFast decay Conventional Logging 28.729.1 Reduced Impact 18.518.3 (Keller et al. in press)
Logging and Sustainability Biological –Water and Energy Exchange –Carbon Storage –Nutrient Cycling –Habitat and Diversity Production system Economic and social
Potential Nutrient Limitation: Selective Logging (30 m 3 removed each 30 y) [Nutrients in kg ha -1 y -1 ] (*) Estimated maximum Mg owing to detection limit Data from Silver et al. 2000 and Fernandes et al. 1997
Logging and Sustainability Production Systems –Given realistic inputs, costs, and benefits, at what rate can logs be selectively removed from the forest over a long period of harvest cycles? –A critical factor in determining production system sustainability is the range of species acceptable to the market.
Keller et al. in press CAFOGROM Model (Alder & Silva)
Logging and Sustainability Long term sustainability of logging depends upon protection of the forest against risks such as fire.
Susceptibility Forest Fire Logging Forest Fire Risk: Positive Flammability Feedback Source: Nepstad et al. 2001
Conclusions Selective logging may release substantial carbon to the atmosphere but this is highly dependent upon area logged and the logging techniques. Nutrients, with the possible exception of K, Mg, and Ca, are unlikely to severely limit productivity on most soils With good management, current models suggest that log production may be maintained at presently profitable levels if the number of merchantable species increases in the future
Acknowledgements Natalino Silva, Greg Asner, MCT and the LBA Central Office at CPTEC LBA-ECO Project Johan Zweede and FFT NASA, US Forest Service, USAID, DFID, EMBRAPA
Estimation of Potential Nutrient Limitation: Selective Logging (30 m 3 removed each 30 y) [Nutrients in kg ha - 1 y -1 ] (*) Estimated maximum Mg owing to detection limit Data from Silver et al. 2000, Fernandes et al. 1997, & Williams et al. 1997