Nutrient losses during a winter low-intensity prescribed fire in a Mediterranean forest

Abstract

Losses of N, P, K and Ca were measured during a prescribed burning in a French Mediterranean Pinus halepensis forest, with understorey of Quereus eoceifera. Nutrient loss was measured by difference between the quantity of a nutrient in the fuel before burning and that found in the postfire remains which were harvested or recovered in small trays. Reduction in fuel weight amounted to 77%, losses from initial fuel elements amounted to 77% for N, 54% for K and 35% for P. No significative loss of Ca was measured. Burning resulted in 7 t ha-l fuel reduction and in loss of 55 kg ha-~ N, 8.5 kg ha-l K and 1.0 kg ha-~ P.

Short-term effects of fire on soil and plant nutrients in palmetto flatwoods

“…1). This result is consistent with the findings that more N than P is volatilized by fire (Gillon and Rapp 1989;Pivello and Coutinho 1992;Cook 1994;Mackensen et al 1996) and that ash has higher concentrations of P than N (Raison et al 1985b;Marcos et al 2009). In a wetland with acidic, sandy soils, the soil extractable N:P ratio after fire was similar to our flatwoods site, but the pre-fire soil extractable N:P ratio was greater than in our site, so the magnitude of the decline was greater (Wilbur and Christensen 1983).…”

“…Regardless of ecosystem type or fire intensity, approximately twice as much N as P is lost to the atmosphere during fire (Gillon and Rapp 1989;Pivello and Coutinho 1992;Cook 1994;Mackensen et al 1996). Thus, ash on the soil surface contains high concentrations of P and low concentrations of N (DeBano and Conrad 1978;Raison et al 1985b), suggesting that fire affects both the absolute and relative availability of soil N and P.…”

Regional patterns of fire recurrence effects on calcareous soils of Mediterranean Pinus halepensis communities

“…Combustion of plant biomass and soil organic horizons results in nitrogen losses by volatilization reported to surpass 64% during experimental fires, and eventually increased by ash leaching or washout (Gillon and Rapp, 1989;Trabaud, 1994;Serrasolses and Vallejo, 1999). Such losses seem to have accumulated through repeated fires in twice-burnt areas, and to have lead to observed lower nitrogen concentrations in organic L horizon.…”

Soil nutrients and microbial activity after early and late season prescribed burns in a Sierra Nevada mixed conifer forest

“…This inconsistency in the published literature is likely due to the complex nature of factors influencing nitrogen pools (soil moisture, leaching, soil erosion, plant uptake and microbial immobilization), the spatial heterogeneity of the nitrogen loss during fire, and the soil depth sampled. Depending on intensity, the effects of fire are typically diminished below 5 cm (Neary et al, 1999), so if soils are sampled below this depth and mixed, as they were in this study, the effect of the burn may be diluted by the unaffected deeper soil horizons (Gillon and Rapp, 1989;Wan et al, 2001).…”