Onsite sediment production and nutrient losses from a low severity burn in the interior northwest

Robichaud, P.R.; Graham, R.T.; Hungerford, R.D. 1994. Onsite sediment production and nutrient losses from a low-severity burn in the Interior Northwest. In: Baumgartner, D.M.; Lotan, J.E.; Tonn, J.R., eds. Proceedings, Interior Cedar-Hemlock-White Pine Forests: Ecology and Management; 1993 March 2-4; Spokane, WA. Pullman, WA: Washington State University Cooperative Extension: 227-232.

Keywords: erosion, prescribed burning, nitrogen loss, soil heating, sediment yield, sediment production

Links:

Abstract: Postharvest residue burning is a common site preparation treatment used in the interior Northwest to reduce forest fuels and prepare sites for tree regeneration. A study was conducted to measure runoff, sediment production, and nutrient changes caused by broadcast burning of logging slash. The site was a northern Idaho mixed conifer forest of western hemlock, grand fir, western white pine, western larch and Douglas-fir. A spring burn (1992) consumed about 50 percent of the litter, 22 percent of the humus, and 79 percent of the woody fuels less than 8 cm in diameter. Heat penetration into the mineral soil was minimal due to moisture present in the lower duff and mineral soil. Temperatures at the mineral soil surface did not exceed 77^oC. Four replications of three, 30-minute simulated rainfall events (50 mm/hr) were used. Low erosion rates and nutrient losses were measured from this burn treatment. These results could help in making land management decisions concerning timing of burning as related to onsite sediment production, fuel reduction and long-term site productivity.

Moscow FSL publication no. 1994a