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Abbreviations KP = charcoal kiln plot; CP = control plot. NomenclaturePignatti (1982) Abstract Aim: Production of wood charcoal is an ancient form of anthropogenic forest use that existed for millennia in Mediterranean countries and only vanished in the last century. As a result, thousands of abandoned charcoal kiln platforms still occur in present-day woodlands. Because of peculiar light and soil properties, the understorey vegetation at these platforms may differ from the surrounding stands. Our study investigated, for the first time, the effects of abandoned kiln platforms on understorey vegetation diversity, composition and biomass production in forests of a Mediterranean area.Location: Tuscany, central Italy.Methods: One 3 9 3 m kiln plot on charcoal kiln area and one 3 9 3 m control plot in the surrounding stands were established in 59 representative sites located in three major forest types dominated by evergreen sclerophylls, deciduous oaks and beech. In each plot, diversity and composition of the understorey community were analysed, together with soil factors (content of C, N, C:N ratio, pH) and light conditions (PAR). A 50 9 50 cm frame was randomly placed in each plot to measure biomass production.

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a b s t r a c tProduction of wood charcoal in the Mediterranean countries started over two millennia ago and vanished almost completely only in the last century. The legacy of this activity are thousands of abandoned charcoal kiln platforms, in which soil and vegetation characteristics are deeply affected. Understanding the consequences of such effects at the forest level demands a better knowledge of the density, distribution and morphology of these sites, as well as the influence of forest type and local geomorphological characteristics. We examined these aspects using field surveys and Airborne Laser Scanning (ALS) data in 1-ha sample quadrats distributed along an altitudinal gradient in three major forest types of Central Italy, namely evergreen sclerophyllous forest, oak-dominated thermophilous deciduous forest and montane beech forest. We found on average 5.5 kiln sites per ha. The highest overall surface proportion covered by charcoal platforms was recorded in oak-dominated forests, due to their generally larger size. In beech forests, kiln platforms were more numerous than in the other two forest types, but smaller. Density was intermediate in the sclerophyllous forests, where the overall proportion of surface was lowest. The charcoal-enriched soil layer was usually single and continuous (e.g. not interrupted by mineral layers). The thickness of this layer was similar in the three forest types, but increased with slope inclination. Several features of our kiln platforms such as density and shape were distinct from others in Central and Northern Europe, probably reflecting different forest histories and purposes for which they were built. Using ALS, we could detect all kiln platforms in beech forest on steep slopes and approximately 75% of the kilns in oak forests on hilly terrain. Hence, all further ecologically-or archaeologically-oriented study in our region at the landscape level will benefit from the use of hillshade and/or slope images from ALS data.

The impact of allergens emitted by urban green spaces on health is one of the main disservices of ecosystems. The objective of this work is to establish the potential allergenic value of some tree species in urban environments, so that the allergenicity of green spaces can be estimated through application of the Index of Urban Green Zones Allergenicity (IUGZA). Multiple types of green spaces in Mediterranean cities were selected for the estimation of IUGZ. The results show that some of the ornamental species native to the Mediterranean are among the main causative agents of allergy in the population; in particular, Oleaceae, Cupressaceae, Fagaceae, and Platanus hispanica. Variables of the strongest impact on IUGZA were the bioclimatic characteristics of the territory and design aspects, such as the density of trees and the number of species. We concluded that the methodology to assess the allergenicity associated with urban trees and urban areas presented in this work opens new perspectives in the design and planning of urban green spaces, pointing out the need to consider the potential allergenicity of a species when selecting plant material to be used in cities. Only then can urban green areas be inclusive spaces, in terms of public health.

stomatal flux-based standard and on real plant symptoms is more appropriated than the exposure-based method for protecting vegetation. From flux-effect relationships, we derived flux-based critical levels (CLef) for forest protection against visible foliar O 3 -like injury. We recommend CLef of 5 and 12 mmol m −2 POD1 for broadleaved species and conifers, respectively. Before using PODY as legislative standard in Europe, we recommend using the CLec for ≥ 25% of crown defoliation in a plot: 17,000 and 19,000 nmol mol −1 h AOT40 for conifers and broadleaved species, respectively.

Plant species allocate resources to multiple defensive traits simultaneously, often leading to so‐called defence syndromes (i.e. suites of traits that are co-expressed across several species). While reports of ontogenetic variation in plant defences are commonplace, no study to date has tested for ontogenetic shifts in defence syndromes, and we know little about the ecological and evolutionary drivers of variation in plant defence syndromes across ontogeny. We tested for ontogenetic variation in plant defence syndromes by measuring a suite of defensive and nutritional traits on saplings and adult trees of 29 oak (Quercus, Fagaceae) species distributed across Europe, North America, and Asia. In addition, we investigated if these syndromes exhibited a phylogenetic signal to elucidate the nature of their macro‐evolutionary variation, whether they were associated with levels of herbivore pressure and climatic conditions, and if any such evolutionary and ecological patterns were contingent on ontogeny. Our analyses revealed three distinct oak defence syndromes: the first included species with high defences, the second species with high defences and low nutrient levels, and the third species with high nutrients and thinner leaves. Interestingly, these defence syndromes remained virtually unchanged across the two ontogenetic stages sampled. In addition, our analyses indicated no evidence for a phylogenetic signal in oak syndromes, a result consistent across ontogenetic stages. Finally, with respect to ecological factors, we found no effect of climatic conditions on defences for either ontogenetic stage, whereas defence syndromes were associated with differing levels of herbivory in adults but not saplings suggesting an association between herbivore pressure and syndrome type that is contingent on ontogeny. Synthesis. Together, these findings indicate that defence syndromes remain remarkably consistent across oak ontogenetic stages, are evolutionarily labile, and while they appear unrelated to climate, they do appear to be associated with herbivory levels in an ontogenetic‐dependent manner. Overall, this study builds towards a better understanding of ecological and evolutionary factors underlying multivariate plant defensive phenotypes.

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