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Although several management options are adopted to redirect post-fire forest ecosystems towards less vulnerable and more resilient and functional communities, little is known about the interactions among tree stand age, pre-fire forest management, and slope aspects, and their consequences for plant species and soil properties recovery immediately after severe wildfires. To address this knowledge need, this study evaluates the post-fire changes in species richness and diversity (with a specific focus on regeneration mechanisms and life forms) of regenerating plants as well as the main physico-chemical and biological properties of burned soils with the reciprocal relations. Plant cover and diversity, and many soil properties have been monitored in forests of southeast Spain with mature, middle and young stands, presence of pre-fire treatments or not, and north and south hillslopes about one year after the fire. To this aim, the reciprocal relationships among soil properties and plants were evaluated adopting a combination of statistical techniques (PERMANOVA, Non-metric Multi-Dimensional Scaling, Distance-based Linear Modelling, Distance-based Redundancy Analysis, and Spearman correlation analysis). The damage to soil and vegetation was so high that both plants and pre-fire soil properties slowly recovered. Only a few life forms of vegetation (geophytes and herbaceous chamaephytes) were influenced by the stand age. If combined with soil aspect, stand age resulted in significantly lower germinating species in mature stands and lower resprouters in young stands, both on south hillslopes. Plant diversity was high, and the post-fire regeneration did not change the species richness and evenness. The post-fire changes in soil properties were limited, and only slight small differences in pH and betaglucosidase among stands of different age were found. No evident associations between soil properties and plant diversity were revealed by the low correlation coefficient. The low variance in plant cover and diversity, as well as in soil properties, resulted in a low accuracy of the dbRDA model to reproduce its variability among sites with different pre-fire characteristics. • An extremely high fire severely damaged soil and vegetation, which both slowly recovered. • Stand age resulted in lower germinating species in mature and south-aspect stands. • Stand age yielded lower resprouters in young stands on south hillslopes. • Post-fire regeneration did not change species richness and evenness. • Post-fire changes in soil properties were limited (except for pH and betaglucosidase). [ABSTRACT FROM AUTHOR]

The effects of hillslope stabilisation techniques on soil properties and vegetation cover of Mediterranean forests affected by wildfires have been deeply explored in the short term, while the long-term evaluations are scarce. Following previous investigations carried out in a pine forest of Castilla-La Mancha (Spain) burned by a severe wildfire in 2012 and treated with log erosion barriers (LEBs) or contour felled log debris (CFD) as post-fire management actions, this study evaluates the changes in soil physico-chemical and biological properties, and vegetation cover eleven years after the fire and structure construction in unburned, burned and untreated (with north or south aspect), and burned and treated soils (with CFDs or LEBs). The results have shown that none of the physico-chemical and biological properties of soil as well as the ground cover significantly differs between sites treated with CFDs and LEBs. The latter structures appear to be more effective in storing organic matter and water in the soil, which is important for post-fire vegetation recovery. The aforementioned effectiveness of post-fire treatments in limiting the changes in soil and vegetation due to wildfire was particularly evident in the burned and untreated sites exposed to the south, which should be prioritised for treatment, since these areas show long-term reductions in soil water content and availability. This prioritisation helps to support a quicker restoration of vegetation cover, which may find water shortage as a limiting factor compared to sites with north aspect. Finally, since, in such a long term, the changes in several soil properties (e.g., most of the enzymatic activities and basal respiration) between unburned, and burned and treated sites disappeared, and vegetation cover was almost fully restored up to the unburned level, it can be confirmed that the analysed hillslope stabilisation techniques were successful in recovering the pre-fire conditions of soil and vegetation conditions that are typical of unburned sites. • Long-term monitoring of effects of wildfire and post-fire management is explored. • Burned/untreated soils exposed to south showed low vegetation cover. • CFDs and LEBs did not differently affect soil properties and ground covers. • Pre-fire soil properties in burned and treated sites recovered. • Vegetation cover was almost fully restored up to the unburned level. [ABSTRACT FROM AUTHOR]

• Organic matter and nutrients were different between treated and untreated soils. • Herbaceous plants were found only in UB and LEB sites. • Increases in OM and nitrogen are associated to more resprouting species. • Increases in pH and again OM are associated to more abundant tree and herbs. • The study indicates the most resilient plant species after post-fire restoration. The medium- and long-term studies about the effectiveness of post-fire management techniques on soil and plant ecology are scarce, although the effects of wildfire and subsequent management can be long lasting. This study has evaluated the changes in the main physico-chemical properties of soil and plant diversity six years after a wildfire and post-fire treatments using contour felled log debris (CFD) and log erosion barriers (LEB) in a Mediterranean pine forest in comparison to unburnt (UB), and burnt but untreated (BNA) sites. Soil texture and pH did not generally change after wildfire and treatments, while organic matter and nutrients were significantly different between the treated soils and the other sites. Herbaceous plants were found only in UB and LEB sites, the latter showing the lowest number of tree species. Shrubs were equally distributed among the four soil conditions. Resprouting and germinating plants increased in the treated sites compared to BNA area, which however showed a higher number of facultative resprouters. The analysis of relationships between soil properties and plant diversity showed that, when organic matter (CFD plots) and nitrogen (LEB plots) contents are noticeably higher compared to BNA soils, more resprouting species are detected. Moreover, significant increases in pH (UB and BNA plots) and organic matter (CFD plots) are associated to more abundant tree and herbaceous species. The study also indicates to forest managers the most resilient plant species after post-fire restoration several years after a wildfire under Mediterranean conditions. [ABSTRACT FROM AUTHOR]

• The effects of mulching on ecosystem multifunctionality (EMF) have been little explored. • EMF increased from burned and untreated to mulched and to unburned sites. • No significant difference in EMF between the two mulches was found. • Mulching only partially dampened the impact of fire on EMF. • Almost all ecosystem functions were associated to soil or vegetation parameters. Straw and wood chips have been widely used as mulch materials to control post-fire erosion in burned forests. However, their effects on ecosystem multifunctionality (EMF) have been little explored. This information is essential to give forest managers insight about the effectiveness of these strategies for restoration of severely-burned forests. To fill this gap, this study has evaluated the short-term (one year after wildfire) changes in ecosystem properties (associated to soil characteristics), structure (linked to plant diversity), individual ecosystem functions, and EMF in a Mediterranean forest. This delicate ecosystem was burned by a wildfire and then mulched with straw or wood chips, and EMF in these conditions was compared to burned and untreated, and unburned sites. The results have shown that: (i) neither wildfire nor mulching significantly changed soil properties with the exception of pH; (ii) in contrast, ecosystem structure significantly declined in mulched plots due to wildfire, and mulching did not limit the alteration in species richness; (iii) among the analysed ecosystem functions, waste decomposition and nutrient cycling, which were significantly higher in unburned soils compared to burned sites, showed intermediate and similar values in mulched plots, while water cycle and wood production (the latter with the exception of unburned plots) were similar among all soil conditions, and climate regulation was significantly higher only in soils mulched with wood chips compared to burned sites; (iv) EMF increased from burned and untreated soils to unburned sites; (v) mulching was effective at limiting the reduction in EMF due to wildfire, but only partially dampened the impact of the fire. Moreover, the combined analysis of ecosystem properties, structure and functions, and EMF revealed that: (i) all functions, except water cycle, were associated to one or more soil or vegetation parameters; (ii) species community composition noticeably influenced several ecosystem functions, and, therefore, EMF; (iii) species richness is a key driver of wood production; (iv) pH, which was found as the most influential soil property on ecosystem functions and EMF, may be considered as an important ecological predictor of forest functions in basic soils of Mediterranean forests. This study may be of practical importance for policymakers and land managers about the most effective actions to preserve the ecosystem EMF in fragile ecosystems, such as the Mediterranean wildfire-affected forest. [ABSTRACT FROM AUTHOR]

Background & Aims: The disruption of homeostasis between proliferation and apoptosis in the colonic epithelium contributes to the pathogenesis of human ulcerative colitis. Mice lacking the transcriptional corepressor myeloid translocation gene related-1 (Mtgr1) display impaired secretory cell lineage development in the small intestine and an increase in proliferation in the crypts of both the small and large intestines. Despite the increase in proliferating cells, the colons of Mtgr1-null mice have a normal cell lineage distribution and normal architecture. To uncover colonic phenotypes in Mtgr1 −/− mice, we stressed the colonic epithelium with low-molecular-weight dextran sodium sulfate (DSS), which is a well-studied model of murine ulcerative colitis. Methods: Mtgr1-null mice were given 3% DSS in their drinking water for 4 days and the colons examined at various times thereafter for ulceration and for changes in proliferation and apoptosis. Results: Treatment with DSS resulted in severe colitis in Mtgr1 −/− mice, at least partially due to increased epithelial apoptosis rates. Transplantation of wild-type and Mtgr1-null bone marrow into irradiated wild-type mice demonstrated that the severe DSS-induced ulceration seen in Mtgr1-null mice was due to a colonic, rather than a hematologic, defect. Importantly, the epithelium of DSS-treated Mtgr1-null mice failed to completely regenerate, showing changes consistent with chronic colitis, even 10 weeks after a single DSS treatment. Conclusions: These findings suggest that Mtgr1 has an important role in crypt survival and regeneration after colonic epithelial ulceration. [Copyright &y& Elsevier]