The study of plant trait-environment links is rarely focused on traits that inform on space occupancy and resprouting (both affecting plant persistence), especially in forest understories. Traits that can effectively capture such key functions are associated with clonality and bud banks. We hypothesized that: 1) climate is the main driver of clonal and bud bank traits, 2) traits related to space occupancy (e.g., greater lateral spread) are more important in more mesic, richer soils forests, and 3) traits related to resprouting ability (e.g., larger bud bank) are more important in more intensively and recently managed forests. We addressed these hypotheses by analysing a unique dataset that is statistically representative of Italian forests heterogeneity and includes three biogeographic regions (Alpine, Continental, Mediterranean). We recorded data for sixteen climatic, soil and management variables. We calculated community weighted mean (CWM) values of seven clonal and bud bank traits for the forest understory vegetation. We used i) redundancy analysis to assess trait-environment relations, and ii) variance partitioning analyses to identifying the relative role of different groups of abiotic variables on CWM variation of all traits combined together, as well as clonal and bud bank traits taken separately. Climate alone had a pervasive effect in determining patterns of clonal and bud bank traits in Italian forest understories, mainly related to the effects of temperature extremes and seasonality. Unexpectedly, soil and management factors alone showed marginal effects on clonal and bud bank traits. However, soil features influenced trait patterns when joined with climate. Our results confirmed that, at the biogeographic scale, climate played a lion-share role in determining persistence-related traits of forest-floor plants. At the local-scale, other interplaying factors (e.g., management, soil variables) may come into play in shaping patterns of the studied plant traits. This study stressed the importance of examining functional trait patterns along complex environmental gradients. © 2019 Elsevier GmbH

In Mediterranean ecosystems an increasing demand for in situ trace gas exchange data is emerging to enhance the adaptation and mitigation strategies under forest degradation. Field-chamber green-house gas fluxes and site characteristics were analysed in two Mediterranean peri-urban pine forests showing degradation symptoms. We examined the effect of different thinning interventions on soil CO<inf>2</inf>, CH<inf>4</inf> and N<inf>2</inf>O fluxes, addressing the relationships with the environmental variables and C and N contents along forest floor-soil layers. Soil temperature resulted as the main driving variable for CO<inf>2</inf> efflux and CH<inf>4</inf> uptake. Soil moisture content and organic matter availability affected CO<inf>2</inf> emission patterns in the two sites. N<inf>2</inf>O fluxes showed a positive correlation with soil moisture under wetter climatic conditions only. GHG fluxes showed significant correlations with C and N content of both forest floor and mineral soil, especially in the deepest layers, suggesting that it should be considered, together with environmental variables when accounting GHG fluxes in degraded forests. Short-term effects of thinning on CO<inf>2</inf> emissions were dependent on disturbance induced by logging operations and organic matter inputs. After thinning CH<inf>4</inf> uptake increased significantly under selective treatment, independently from specific site-induced effects. N<inf>2</inf>O fluxes were characterized by low emissions in both sites and were not affected by treatments. Soil CO<inf>2</inf> efflux was the largest component of global warming potential (GWP) from both sites (11,553 kg ha⁻¹ y⁻¹ on average). Although it has a large global warming potential, N<inf>2</inf>O contribution to GWP was about 131 kg CO<inf>2</inf>eq ha⁻¹ y⁻¹. The contribution of CH<inf>4</inf>-CO<inf>2</inf> equivalent to total GWP showed a clear and significant CH<inf>4</inf> sink behaviour under selective treatment (36 kg ha⁻¹ y⁻¹ on average). However, in the short-term both thinning approaches produced a weak effect on total GWP. © 2018 Elsevier B.V.