Soil Respiration Changes after Prescribed Fires in Spanish Black Pine (Pinus nigra Arn. ssp. salzmannii) Monospecific and Mixed Forest Stands

Abstract

Soil respiration is a major carbon pathway sensitive to environmental changes. Using prescribed burnings to reduce fuel accumulation and lower risks of large-scale wildfires has recently become more important. Prescribed burning can significantly alter the soil environment, but its effect in practice on soil respiration is not sufficiently understood. We evaluated the effects of prescribed burning on soil respiration before and after burning (May-July 2016). Prescribed burning was conducted in two natural pine areas by comparing a mixed stand of Pinus nigra Arn. ssp. salzmannii with Pinus pinaster Ait. to a pure stand of Pinus nigra Arn. ssp. salzmannii in the central Iberian Peninsula. Soil respiration was measured by an EGM-4 (Environmental Gas Monitor) infrared gas analyser in both burned and unburned (control) plots. Burnings were low-intensity, and slightly more energetic in the pure stand given its larger litter volume. Post-burning soil respiration followed a similar evolution to that in the control plots, but was greater in the pure stand burned zone and slightly lower in the burned plots in the mixed stand. No significant differences were found in any stand. Soil respiration significantly changed in temporal evolution due to increasing temperatures when summer began. We conclude that prescribed fire induces no changes in SR immediately after fire. This study helps understand how prescribed burnings can affect soil respiration in pure and mixed Spanish black pine forest stands.

Soil scarification favors natural regeneration of Pinus pinea in Lebanon forests: Evidences from field and laboratory experiments

“…In addition, emerged seedlings are also very easily detectable by the predators (including birds and rodents) in the absence of ground vegetation as it was observed in other studies (e.g. Sagra et al, 2017).…”

“…Similarly, Sagra et al (2018) reported that ash was a limiting factor on seed germination and seedling survival of P. pinaster in a field experiment. Such results could be explained by the alteration of soil properties after controlled burning in particular a reduced soil moisture and soil respiration and an increased soil temperature (Plaza-Álvarez et al, 2017).…”

Early spring prescribed burning in mixedPinus halepensisMill. andPinus pinasterAit. stands reduced biological soil functionality in the short term

“…Thus in Mediterranean regions, prescribed burning is usually carried out in spring (early season) or autumn (late season) when the moisture of vegetation and soil is high to obtain low‐burn intensity, which implies low soil organic layer combustion (McNabb & Cromack jr, 1990; Úbeda, Pereira, & Badía, 2018). When the prescribed fire is performed under these humidity and temperature conditions, temporal changes in soil properties are usually limited to the short term (Catalanotti et al, 2018; Mataix‐Solera & Cerdà, 2009; Merino et al, 2019; Plaza‐Álvarez et al, 2017, 2018).…”

“…Microbiological and physico‐chemical soil properties have been widely used as soil quality indicators to evaluate fire‐induced changes and soil degradation (Lucas‐Borja et al, 2012; Úbeda, Alcañiz, Borges, Outeiro, & Francos, 2019). Some microbiological parameters, such as soil basal respiration, microbial biomass, and certain soil enzyme activities, have been used to quantify soil biological disturbance in relation to burn severity (García‐Orenes et al, 2017; Mabuhay, Nakagoshi, & Isagi, 2006; Moya et al, 2018; Plaza‐Álvarez et al, 2017). So, the enzymatic activities related to carbon, nitrogen, and phosphorus cycles, in addition to characteristic microbial indicators, such as soil respiration, have been proposed as indicators of soil functionality (Fontúrbel et al, 2012; Hedo, Lucas‐Borja, Wic, Andrés‐Abellán, & Las Heras, 2015).…”

“…When the prescribed fire is performed under these humidity and temperature conditions, temporal changes in soil properties are usually limited to the short term (Catalanotti et al, 2018;Mataix-Solera & Cerdà, 2009;Merino et al, 2019;Plaza-Alvarez et al, 2017.…”