Evolución temporal de las propiedades del suelo tras el tratamiento de extracción de madera quemada en la Sierra de Mariola

Estudio realizado para evaluar la evolución temporal del suelo de un bosque mediterráneo en la Sierra de Mariola en Alicante, España, cinco años después de sufrir un incendio y haberse aplicado un tratamiento de extracción de madera quemada. Analizando propiedades físicas, químicas y biológicas del suelo se observa una clara degradación en la zona de saca de madera, mientras que la zona de control, donde no se extrajo madera, presenta valores estables e incluso de recuperación en algunos parámetros. El tratamiento de saca de madera ha provocado una erosión que ha afectado a la capa más fértil del suelo, reduciendo su materia orgánica y la presencia de microrganismos y nutrientes disponibles para las plantas. Con los resultados obtenidos podemos concluir que el tratamiento de extracción de madera quemada ha supuesto un proceso desfavorable para la recuperación del ecosistema tras sufrir un incendio.Study carried out to evaluate the temporal evolution of the soil of a Mediterranean forest in Sierra de Mariola at Alicante, Spain, five years after suffering a forest fire and having applied a burnt wood extraction treatment. Analyzing the physical, chemical and biological properties of the soil, a clear degradation is observed in the area of wood extraction, while the control zone, where no wood was extracted, presents stable values and even recovery in some parameters. The treatment of wood extraction has caused an erosion that has affected the most fertile layer of the soil, reducing its organic matter and the presence of microorganisms and nutrients available for the plants. With the results obtained we can conclude that the treatment of wood burnt extraction has been an unfavorable process for the recovery of the ecosystem after suffering a forest fire

How clear-cutting affects fire severity and soil properties in a Mediterranean ecosystem

Forest management practices in Mediterranean ecosystems are frequently employed to reduce both the risk and severity of wildfires. However, these pre-fire treatments may influence the effects of wildfire events on soil properties. The aim of this study is to examine the short-term effects of a wildfire that broke out in 2015 on the soil properties of three sites: two exposed to management practices in different years e 2005 (site M05B) and 2015 (site M15B) e and one that did not undergo any management (NMB) and to compare their properties with those recorded in a plot (Control) unaffected by the 2015 wildfire. We analyzed aggregate stability (AS), soil organic matter (SOM) content, total nitrogen (TN), carbon/ nitrogen ratio (C/N), inorganic carbon (IC), pH, electrical conductivity (EC), extractable calcium (Ca), magnesium (Mg), sodium (Na), and potassium (K), microbial biomass carbon (Cmic) and basal soil respiration (BSR). In the managed plots, a clear-cutting operation was conducted, whereby part of the vegetation was cut and left covering the soil surface. The AS values recorded at the Control site were significantly higher than those recorded at M05B, whereas the TN and SOM values at NMB were significantly higher than those recorded at M05B. IC was significantly higher at M05B than at the other plots. There were no significant differences in C/N ratio between the analyzed sites. Soil pH at M05B was significantly higher than the value recorded at the Control plot. Extractable Ca was significantly higher at NMB than at both M05B and the Control, while extractable Mg was significantly lower at M05B than at NMB. Extractable K was significantly lower at the Control than at the three fire-affected plots. Cmic was significantly higher at NMB than at the Control. BSR, BSR/C and BSR/Cmic values at the fire-affected sites were significantly lower than those recorded at the Control. No significant differences were identified in Cmic/C. Overall, a comparison of the pre-fire treatments showed that NMB was the practice that had the least negative effects on the soil properties studied, followed by M15B, and that fire severity was highest at M05B due to the accumulation of dead plant fuelThis study was supported by the POSTFIRE Project (CGL2013-47862-C2-1 and 2-R) and the POSTFIRE_CARE Project (CGL2016-75178-C2-2-R [AEI/FEDER, UE]),financed by the Spanish Research Agency (AIE) and the European Union through European Funding for Regional Development (FEDER) and the FPU Program (FPU 014/00037) of the Ministry of Education, Cultureand Sports and Program 2014SGR825 of the Generalitat de Catalunya

Effects of salvage logging on soil properties and vegetation recovery in a fire-affected Mediterranean forest: A two year monitoring research

Post-firemanagement can have an additional impact on the ecosystem; in somecases, evenmore severe than the fire. Salvage logging (SL) is a common practice in most fire-affected areas. The management of burnt wood can determine microclimatic conditions and seriously affect soil properties. In some cases, the way of doing it, using heavy machinery, and the vulnerability of soils to erosion and degradation can make this management potentially aggressive to soil. Research was done in “Sierra de Mariola Natural Park” (E Spain). A forest fire (N500 ha) occurred in July 2012. In February 2013, SL treatment was applied in a part of the affected forest. Plots for monitoring this effect were installed in this area and in a similar nearby area where no treatment was done, used as control (C). Soil samplings were done immediately after treatment and every 6 months during two years. Some soil properties were analysed, including organic matter (OM) content, nitrogen (N) available phosphorous (P) basal soil respiration (BSR), microbial biomass carbon (Cmic), bulk density (BD),water repellency (WR), aggregate stability (AS) and field capacity (FC). SL treatment caused an increase in BD, a decrease of AS, FC, OMand N. In the control area, in general the soil properties remained constant across the 2 years of monitoring, and the microbial parameters (BSR and Cmic), initially affected by the fire, recovered faster in C than in the SL area. Plant recovery also showed some differences between treatments. No significant differenceswere observed in the number of plant species recorded (richness) comparing C versus SL plots, but the number of individuals of each species (evenness)was significantly higher in C plots. In conclusion, we can affirmthat for the conditions of this study case, SL had a negative effect on the soil-plant system.To the “Ministerio de Economía and Competitividad” of the Spanish Government for financing the POSTFIRE project (CGL2013- 47862-C2-1-R) and Alcoi counci

Relationships between soil water repellency and microbial community composition under different plant species in a Mediterranean semiarid forest

Soil water repellency (SWR) can influence many hydrological soil properties, including water infiltration, uneven moisture distribution or water retention. In the current study we investigated how variable SWR persistence in the field is related to the soil microbial community under different plant species (P. halepensis, Q. rotundifolia, C. albidus and R. officinalis) in a Mediterranean forest. The soil microbial community was determined through phospholipid fatty acids (PLFA). The relationships between microbiological community structure and the soil properties pH, Glomalin Related Soil Protein (GRSP) and soil organic matter (SOM) content were also studied. Different statistical analyses were used: Principal Component Analysis (PCA), ANOVA, Redundancy Analysis and Pearson correlations. The highest concentrations of PLFA were found in the most water repellent samples. PCA showed that microorganism composition was more dependent of the severity of SWR than the type of plant species. In the Redundancy Analysis, SWR was the only significant factor (p<0.05) to explain PLFA distributions. The only PLFA biomarkers directly related to SWR were associated with Actinobacteria (10Me16:0, 10Me17:0 and 10Me18:0). All the results suggest that a strong dependence between SWR and microbial community composition.Ministerio de Ciencia e Innovación CGL2010-21670-C02-0

Temporal characterisation of soil-plant natural recovery related to fire severity in burned Pinus halepensis Mill. forests

Despite Mediterranean ecosystems' high resilience to fire, both climate and land use change, and alterations in fire regimes increase their vulnerability to fire by affecting the long-term natural recovery of ecosystem services. The objective of this work is to study the effects of fire severity on biochemical soil indicators, such as chemical composition or enzymatic activity, related to time after fire and natural vegetation recovery (soil-plant interphase). Soil samples from three wildfires occurring 3, 15 and 21 years ago were taken in the south-eastern Iberian Peninsula (semiarid climate). Sampling included three fire severity levels in naturally regenerated (and changing to shrublands) Pinus halepensis Mill. forests. In the short-term post-fire period, phosphorus concentration, electrical conductivity and urease activity were positively linked to fire severity, and also influenced β-glucosidade activity in a negative relationship. During the 15–21-year post-fire period, the effects related to medium-high fire severity were negligible and soil quality indicators were linked to natural regeneration success. The results showed that most soil properties recovered in the long term after fire (21 years). These outcomes will help managers and stakeholders to implement management tools to stabilise soils and to restore burned ecosystems affected by medium-high fire severity. Such knowledge can be considered in adaptive forest management to reduce the negative effects of wildfires and desertification, and to improve the resilience of vulnerable ecosystems in a global change scenario.This study was supported by a grant for research initiation provided by the Excma. Diputación Albacete (DIPU4-AB2015) and by the funds provided by University Castilla-La Mancha to the Forest Ecology Research Group.The authors with to thank the Spanish Institute for Agricultural and Food Research and Technology (INIA) for the funding awarded through National Research Projects GEPRIF (RTA2014-00011-C06)

La repelencia al agua inducida por el fuego está controlada por pequeñas variaciones en las propiedades del suelo

Fire induced soil water repellency (WR) is controlled by many different factors (temperature reached, amount and type of fuel, etc.). Soil properties may determine the occurrence and intensity of this property in burned soils. The objectives of this paper are to make advances in the study of soil properties as key factors controlling the behaviour of fire-induced WR, and to study the impact of pre-fire SOM content and SOM quality in fire-induced soil WR. In this research, experimental laboratory burnings were carried out using soil samples from different sites with different lithologies, soil types and plant species. Soil samples from the same site differ only in quantity and quality of soil organic matter, as they were collected from under different plant species. All soil samples were heated in a muffle furnace at 200, 250, 300 and 350 ºC without the addition of any fuel load. WR was measured using the water drop penetration time test (WDPT). The results showed significant differences between soil types and plant species, indicating that small differences in soil properties may act as key factors controlling the development and persistence of WR reached, with burned soil samples ranging from wettable to extremely water repellent. The main soil property controlling the response was texture, specifically sand content. The quality of organic matter was also observed to have an effect, since soil samples from the same site with similar organic matter contents, but collected from beneath different plant species, showed different WR values after burningLa repelencia al agua (WR) inducida por el fuego es una propiedad controlada por muchos factores diferentes (temperaturas alcanzadas, cantidad y tipo de combustible, etc.). Algunas propiedades del suelo pueden determinar la presencia y la intensidad de esta propiedad en los suelos quemados. Los objetivos principales son: avanzar en el estudio de la influencia de algunas propiedades clave en el control del comportamiento de la WR en suelos quemados, así como estudiar la influencia de la cantidad y la calidad de la materia orgánica del suelo en su desarrollo cuando es afectada por el calentamiento. En éste estudio, hemos realizado quemas controladas en laboratorio utilizando muestras de suelo de diferentes sitios con litologías y tipos de suelos diferentes y recogidas bajo distintas especies vegetales. Las muestras recogidas en diferentes sitios difieren en algunas propiedades del suelo, mientras que las muestras de suelo tomadas del mismo sitio sólo se diferencian en la cantidad y la calidad de la materia orgánica del suelo, ya que se recogieron bajo distintas especies de plantas. Todas las muestras de suelo se calentaron en horno de mufla a 200, 250, 300 y 350 ºC. La repelencia al agua se midió mediante el test del tiempo de penetración de la gota de agua (WDPT). Los resultados mostraron diferencias significativas entre los tipos de suelos y especies vegetales, y se comprobó que pequeñas diferencias en algunas propiedades del suelo pueden actuar como factores clave controlando el desarrollo y persistencia de la repelencia al agua, con muestras de suelo quemadas que variaban entre hidrofílicas a extremadamente repelentes al agua. La propiedad que principalmente controló el comportamiento de la repelencia al calentamiento fue la textura y más concretamente el contenido de arena. Por otro lado se observó que la calidad de la materia orgánica también afecta, ya que muestras de suelo de mismo sitio y con contenido de materia orgánica similar, pero tomadas bajo diferentes especies vegetales mostraron valores muy diferentes de repelencia al agua tras la quema

Piezometric evolution in the aquifer of Aspe (Alicante)

El aprovechamiento de las aguas subterráneas de pequeños acuíferos ha jugado un papel fundamental en el desarrollo local, no siempre bien conocido y valorado. El acuífero de Aspe, en la provincia de Alicante, es un ejemplo en que este aprovechamiento ha estado relacionado históricamente con el crecimiento y desarrollo de la localidad de Aspe. La fuerte presión a la que se vio sometido durante buena parte del s. XX le llevó a una situación de sobreexplotación, de la cual apenas hay información. El abandono de muchas captaciones y la transformación del uso del territorio han permitido un cambio de su situación en las últimas décadas. El principal objetivo del presente trabajo ha sido actualizar el estado de conocimiento que se tiene de él y establecer su situación hidrodinámica. El seguimiento piezométrico ha permitido establecer una sectorización en función del comportamiento de los niveles piezométricos. Así, los sectores de las Fuentes y Tolomó han mostrado un ascenso progresivo, el cual no se corresponde con el comportamiento observado en los sectores de Alcaná y La Ofra. Estas diferencias de comportamiento apuntan a posibles desconexiones piezométricas entre sectores del acuífero.The use of groundwater in small aquifers has played a key role in local development, not always well known and valued. The aquifer of Aspe, in the province of Alicante, is an example in which this exploitation has been historically related to the growth and development of the town of Aspe. The strong pressure to which it was subjected during the twentieth century led to a situation of overexploitation, of which there is scarcely information. The abandonment of many wells and the transformation of land use have allowed a change of its situation in the last decades. The main objective of the present work has been to update the state of knowledge about it and establish its hydrodynamic situation. The piezometric monitoring has allowed to establish a sectorization according to the behaviors of the levels. Thus, the sectors of the Fuentes and Tolomó have shown a progressive piezometric level rise, which does not correspond to the behavior observed in the sectors of Alcaná and La Ofra. These differences in behavior point to possible piezometric disconnections between sectors of the aquifer.Este trabajo se ha realizado dentro del marco del proyecto ALTERACLIM (CGL2015-69773-C2-1) financiado por el Ministerio de Economía, Industria y Competitividad

El tipo de vegetación y la presencia de cenizas como factores en la evolución temporal de la repelencia al agua tras un incendio forestal

Tras un incendio forestal, el fuego puede inducir la aparición de repelencia al agua del suelo. La repelencia al agua del suelo puede variar en el espacio y el tiempo en función de la vegetación, la presencia de cenizas y la humedad del suelo. En este estudio se analiza la evolución de la repelencia al agua del suelo inducida por el fuego en función de estos factores, y se proponen medidas para favorecer la restauración de suelos afectados por incendios. Para ello, se seleccionaron parcelas de suelo quemado y no quemado (control) bajo pino y matorral en un área recientemente incendiada (Gorga, Alicante, Este de España). En parte de las parcelas se mantuvo la capa de ceniza, mientras que en otras se retiró la capa de cenizas simulando los efectos de la erosión. Finalmente, en un tercer grupo, se llevó a cabo un riego percolante para simular una buena entrada de agua en el perfil del suelo que podría darse si las primeras lluvias son copiosas pero de baja intensidad. Durante la época seca, el contenido en humedad del suelo fue significativamente menor en las parcelas quemadas debido a la repelencia al agua inducida por el fuego y a la disminución de la cobertura vegetal. Durante la estación húmeda, la humedad del suelo fue menor en las parcelas control debido a la evaporación directa del agua interceptada por la vegetación y el consumo realizado por las raíces. El fuego incrementó la repelencia al agua sólo en parcelas bajo pino. La repelencia disminuyó en la estación húmeda, desapareciendo a partir de enero y volviendo a aparecer tras la disminución de las lluvias. Esta recuperación de los valores iniciales de repelencia fue menor en los lugares donde se simuló la erosión de las cenizas. En las parcelas no quemadas, las fluctuaciones estacionales fueron menos importantes. En general, la retirada de cenizas favorece una rápida disminución de la repelencia al agua, ya que puede inducir un lavado de compuestos hidrofóbicos. El riego percolante realizado inmediatamente tras el fuego contribuyó también a un descenso de la repelencia al agua.After wildfires, burning may induce the occurrence of soil water repellency. Soil water repellency may vary in space and time in function of vegetation, the presence of ash and soil moisture. This study analyzes the evolution of fire-induced soil water repellency in function of these factors, and proposes measures to promote the restoration of fire-affected soils. Burnt and unburnt (control) soil plots under pine and shrub from a recently burned area (Gorga, Alicante, SE Spain) were established. Three treatments were applied: in some of the plots, the original ash layer was kept on the ground; in a second group, the ash layer was removed for simulating the effects of erosion; finally, in a third group, percolating irrigation was conducted to simulate a possible good input of water into the soil profile after burning, that could occur if the first rains were with high quantity but low intensity. During the dry season, soil moisture content was significantly lower in burned plots due to fire-induced water repellency and reduced vegetation cover. During the wet season, soil moisture decreased in the control unburnt plots due to direct evaporation of water intercepted by vegetation and consumption by roots. Fire increased soil water repellency only in plots under pine. Water repellency decreased during the wet season, disappearing in January and reappearing after declining rainfalls. This baseline recovery of soil water repellency was lower where ash removal was simulated. In unburned plots, seasonal fluctuations were less important. In general, ash removal promotes a rapid reduction of water repellency, since it can induce washing of hydrophobic compounds. Irrigation performed immediately after the fire also contributed to decreased water repellency.España Ministerio de Economía y Competitividad. proyecto HYDFIRE (CGL2010-21670-C02-01

Do fire severity effects on soil change in space and time in the short-term? What ash tells us

n the absence of data, the impact of fire, especially wildfires, is measured analysing the fire severity. This post-fire assessment is very useful because allow to identify the degree of destruction imposed by the fire. Among the techniques used to determine fire severity, ash colour is often used, that permit identify the degree of organic matter consumption (darker ash uncompleted combustion, lighter ash completed combustion). The objective of this paper was observed if fire severity changes in space and time, according to ash colour analysis, applying an index. The ash colour analysis was carried out one and fifteen days after the fire. In this area we identified ash with four different colours, black (B) dark grey (DG), light gray (LG) and white colour (W) and some uncovered areas classified as bared soil (BS). Black and DG represent medium fire severity, LG and W, higher severity. The results showed that in the studied fire, the severity was high and a great part of the plot was uncovered by ash (BS). Fifteen days after BS increased as the fire severity index, from 6.05 to 6.45, showing that during this period the ash redistribution in a short period after the fire can influence the fire severity assessment. We did not identified significant differences between measurements and the coefficient of variation (CV%) remained the same. However significant differences were identified with the spatial correlation analysis with Global Moran's I and the spatial structure of fire severity index. This is evidence that ash color changed in this period in the space and the traditional statistical methods did not detected, only with spatial analysis. The analysis of fire severity using ash color some days after the fire can induce important errors, because wind can (re)mix ash and a particle produced in one area can be easily exported to otherSpanish Ministry of Science and Innovation for funding through the HYDFIRE project CGL2010-21670-C02-0