Successional stage after land abandonment modulates fire severity and post-fire recovery in a Mediterranean mountain landscape

Abstract

This study analyses the effect of successional stage after farmland terrace abandonment on post-fire plant recovery in a Mediterranean landscape. Specific objectives of the study were to (1) compare fuel characteristics and fire severity in three successional stages after farmland abandonment – dry grassland, dense shrubland and pine stands; (2) analyse the effect of pre-fire successional stage and fire severity on vegetation recovery and (3) analyse the relative vulnerability (i.e. potential for ecosystem shift and soil degradation) to wildfires of the successional stages. We assessed 30 abandoned terraces (15 unburned and 15 burned), with diverse successional stages, on the Xortà Range (south-east Spain). Post-fire recovery was measured 1, 4 and 7 years after fire. The successional stages varied in aboveground biomass, litter amount, vertical structure and continuity of plant cover, and flammability. Dry grassland showed the lowest fire severity, whereas no differences in severity were found between shrubland and pine stands. One year after fire, plant cover was inversely related to fire severity; this relationship attenuated with time after fire. Post-fire recovery of pine stands and shrubland led in both cases to shrublands, contributing to landscape homogenisation. The pine stands showed the largest changes in composition due to fire and the lowest post-fire plant recovery – a sign of high vulnerability to fire.

Increased aridity drives post‐fire recovery of Mediterranean forests towards open shrublands

“…3), short-term simulations were technically 'transient', showing large variability in plant composition between simulations, mainly depending on initial conditions and the specific stochastic fire sequence realized in each simulation. In old fields, assemblies of shrubs and pines without oaks prevail under the current fire regime Pausas & Lloret, 2007;L opez-Poma et al, 2014), with pine disappearing under repeated fires (Daskalakou & Thanos, 1996;Eugenio & Lloret, 2004). first century in Fig.…”

“…This approach was sufficiently accurate as it was found that the main limitation to pine persistence was fire recurrence and associated post-fire availability of pine seeds (Thanos & Daskalakou, 2000;Baeza et al, 2007;Tucker & Cadotte, 2013;L opez-Poma et al, 2014): in the present model, pines could not survive even when they were competitively favoured over oaks, if two fires would occur too close to each other (i.e. This approach was sufficiently accurate as it was found that the main limitation to pine persistence was fire recurrence and associated post-fire availability of pine seeds (Thanos & Daskalakou, 2000;Baeza et al, 2007;Tucker & Cadotte, 2013;L opez-Poma et al, 2014): in the present model, pines could not survive even when they were competitively favoured over oaks, if two fires would occur too close to each other (i.e.…”

Effects of a large wildfire on vegetation structure in a variable fire mosaic

“…, López‐Poma et al. ). We studied the effects of a large wildfire on vegetation structure within dry sclerophyll forest, woodland and heath vegetation types, where a variable mosaic of fire histories had previously been established.…”

Comparative Assessment of Goods and Services Provided by Grazing Regulation and Reforestation in Degraded Mediterranean Rangelands

“…Land degradation in the Mediterranean is a multifaceted process that results from the independent or combined effect of factors such as land cover conversion (Alphan ), agriculture and rangeland mismanagement (Cerdà et al ; García‐Orenes et al ), and frequent or severe wildfires (Guénon et al ; López‐Poma et al ), which are ultimately driven by social and economic changes (Abu Hammad & Tumeizi ) and often lead to soil erosion (Cerdà et al ) and long‐term loss of natural vegetation (FAO ). Specifically for rangelands, overgrazing is considered as the key degradation factor in many regions of the world, as it results in increased soil and water losses, decrease and degradation of the vegetation cover and critical changes in regulating ecosystem services (Cerdà & Lavee ; Mekuria & Aynekulu ; Angassa ).…”