2024-03-28T17:09:04Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1230142019-12-10T12:25:12Zcom_10261_62com_10261_6col_10261_188
Soil gross N transformation rates after a wildfire and straw mulch application for burned soil emergency stabilization.
Gómez Rey, María Xesús
González Prieto, Serafín Jesús
Burned Area Emergency Response
gross N fluxes
gross mineralization
gross nitrification
gross NH4 +-N immobilization
gross NO3 --N immobilization
mulching
post-fire rehabilitation.
Effects of fire and post-fire mulching for soil protection on N transformations were evaluated in the
laboratory 4, 8 and 12 months after a wildfire in the 0-2 cm layer of a burned soil without (BS) or with straw
mulch (BSM) and an unburned soil (US). The relationships between the gross N rates calculated with the
FLUAZ model (Mary et al. 1998) and 19 soil characteristics were also explored. The gross N mineralization
(m) and NH4
+ immobilization rates (ia) were similar and significantly correlated (p< 0.001), and decreased
during the incubation. Both m and ia were higher in burned than in unburned soils and, despite a reduction
with time, differences were still three-fold at t= 12 months. Treatment explained half the variation of gross
nitrification (kn), which was always low in US and nil in burned soils. Nitrate immobilization (in) was the
only gross rate that was: a) higher in unburned than in burned soils; b) higher after 12 months than in
previous samplings; and c) negatively affected by mulching. Both m and ia were positively correlated with
soil pH, initial inorganic-N pools and extractable-Mn (p< 0.05 to p< 0.001) and negatively correlated with
soil water holding capacity and contents of total-C, total-N, extractable-Cu and extractable-Zn (p< 0.05 to
p< 0.001). Both kn and in were negatively correlated with soil characteristics. Despite the strong correlations
of pH and total-C and N with the gross N transformations, the former variables were never included in the
best multiple linear models for the latter. Besides the initial NH4
+-N or NO3
--N contents, all but one best
multiple regressions for m and ia included one or two available nutrients, in particular Cu, K, P and Mn.
Multiple regressions of kn were only found for US and they included two nutrients (Ca and K, or K, Zn and
electrical conductivity). Considering all samples and incubation intervals together, two-thirds of variance
was explained by a model with the initial NO3
--N , the available-Cu and P content. Mulching of burned soil
gave a short-lived stimulation of m and ia and a sustained reduction of in.
Peer reviewed
2015-10-05T13:24:42Z
2015-10-05T13:24:42Z
2015
artículo
http://purl.org/coar/resource_type/c_6501
Biology and Fertility of Soils 51: 493-505 (2015)
http://hdl.handle.net/10261/123014
10.1007/s00374-015-0997-0
en
Postprint
Sí
open
Springer