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Control of crop pests by shifting host plant availability and natural enemy activity at landscape scales has great potential to enhance the sustainability of agriculture. However, mainstreaming natural pest control requires improved understanding of how its benefits can be realized across a variety of agroecological contexts. Empirical studies suggest significant but highly variable responses of natural pest control to land‐use change. Current ecological models are either too specific to provide insight across agroecosystems or too generic to guide management with actionable predictions. We suggest obtaining the full benefit of available empirical, theoretical, and methodological knowledge by combining trait‐mediated understanding from correlative studies with the explicit representation of causal relationships achieved by mechanistic modeling. To link these frameworks, we adapt the concept of archetypes, or context‐specific generalizations, from sustainability science. Similar responses of natural pest control to land‐use gradients across cases that share key attributes, such as functional traits of focal organisms, indicate general processes that drive system behavior in a context‐sensitive manner. Based on such observations of natural pest control, a systematic definition of archetypes can provide the basis for mechanistic models of intermediate generality that cover all major agroecosystems worldwide. Example applications demonstrate the potential for upscaling understanding and improving predictions of natural pest control, based on knowledge transfer and scientific synthesis. A broader application of this mechanistic archetype approach promises to enhance ecology's contribution to natural resource management across diverse regions and social‐ecological contexts. [ABSTRACT FROM AUTHOR]

We examined the main and interactive effects of factors related to habitat filtering, dispersal dynamics, and biotic interactions, on tree-level population dynamics of a subset of species composing the epiphytic lichen pool in an alpine forest. We tested these processes evaluating the population size of 14 lichen species on six hundred and sixty-five trees within a 2 ha plot located in a high elevation alpine forest of the eastern Italian Alps. Our results indicate that community assembly patterns at the tree-level are underpinned by the simultaneous effects of habitat filtering, dispersal, and biotic interactions on the fine-scale population dynamics. These processes determine how the single species are sorted into community assemblages, contributing to tree-level community diversity and composition patterns. This corroborates the view that the response of lichen communities to environmental gradients, in terms of compositional and diversity shifts, may reflect differential species responses to different drivers. [ABSTRACT FROM AUTHOR]

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The effectiveness of conservation interventions for maximizing biodiversity benefits from agri-environment schemes (AESs) is expected to depend on the quantity of seminatural habitats in the surrounding landscape. To verify this hypothesis, we developed a hierarchical sampling design to assess the effects of field boundary type and cover of seminatural habitats in the landscape at two nested spatial scales. We sampled three types of field boundaries with increasing structural complexity (grass margin, simple hedgerow, complex hedgerow) in paired landscapes with the presence or absence of seminatural habitats (radius 0.5 km), that in turn, were nested within 15 areas with different proportions of seminatural habitats at a larger spatial scale (10 × 10 km). Overall, 90 field boundaries were sampled across a Mediterranean region (northeastern Italy). We considered species richness response across three different taxonomic groups: vascular plants, butterflies, and tachinid flies. No interactions between type of field boundary and surrounding landscape were found at either 0.5 and 10 km, indicating that the quality of field boundary had the same effect irrespective of the cover of seminatural habitats. At the local scale, extended-width grass margins yielded higher plant species richness, while hedgerows yielded higher species richness of butterflies and tachinids. At the 0.5-km landscape scale, the effect of the proportion of seminatural habitats was neutral for plants and tachinids, while butterflies were positively related to the proportion of forest. At the 10-km landscape scale, only butterflies responded positively to the proportion of seminatural habitats. our study confirmed the importance of testing multiple scales when considering species from different taxa and with different mobility. We showed that the quality of field boundaries at the local scale was an important factor in enhancing farmland biodiversity. For butterflies, AESs should focus particular attention on preservation of forest patches in agricultural landscapes within 0.5 km, as well as the conservation of seminatural habitats at a wider landscape scale. [ABSTRACT FROM AUTHOR]

Epiphytic lichens are a functionally important and species-rich component of Alpine forests, including several species of conservation concern. Their dependence on specific host trees predicts that forests with different tree species composition host different lichen communities, enhancing lichen diversity in forest landscapes. In this study, we tested for the first time the effect of forest type on patterns of epiphytic lichen diversity, in the Italian Alps. We sampled the main forest types of the South Tyrol, a typical Alpine region of Italy. We also assessed the influence of factors related to forest structure and climatic conditions. Our results demonstrate that different forest types host statistically different lichen communities, suggesting that the conservation of lichen diversity is entrusted to the maintenance of forest landscape heterogeneity, including forest types of minor economic value and rural habitats. The highest number of species was found in grazed larch forests and in high-elevation spruce forests, while the poorest pool was found in low-elevation spruce forests, beech forests and Scots pine ( Pinus sylvestris ) forests. High-elevation spruce forests also had the highest number of red-listed lichens, as the non-intensive management of these forest type allows the establishment of a rich lichen biota. Our results also emphasize the role for lichen conservation of some forest types that are of minor economic importance, such as oak ( Quercus pubescens ), riparian, and silver-fir ( Abies alba ) forests. This can also apply to grazed larch ( Larix decidua ) forests that are maintained by traditional farming, which shape one of the most pleasing aspects of the Italian Alpine landscapes. [ABSTRACT FROM AUTHOR]

Abstract: In the Alps, many forests are under abandonment because of direct protection or the unprofitability of timber production. The objective of this study was to analyse the effect of silviculture abandonment on the species richness and composition of epiphytic and dead wood-dwelling lichens in silver fir woodlands. An abandoned and a currently non-intensively managed forest watershed of the eastern Italian Alps that were matched for topography, stand structure, plant community and history of use were selected and randomly sampled for the lichen diversity of their silver fir mature stands. Generalised linear mixed models were used for the analyses of the species richness, whereas the species composition patterns were explored by redundancy analysis. The diversity of both of the lichen guilds were explained by the microhabitat conditions related to the contrasting management regimes, but they had opposite responses to the abandonment of the silvicultural activities. The epiphytic lichen communities were richer in species in the managed than in the abandoned silver fir woodlands. However, the effect of a 50year management cessation on the epiphytic lichens may change in the long term when natural disturbances create gaps and increase the attributes of old-growth forests. The dead wood-dwelling lichen species richness was higher in the abandoned forest because an increased availability of types of dead wood is usually rare in managed forests. The dead wood-dwelling lichen communities of the managed forests were a subset of a more diverse community that was developing in the abandoned forest. Our results indicated that, in non-intensively managed silver fir mature stands, lichen diversity may benefit from the retention of logs and snags, which provide habitat features typical of old-growth forests. [Copyright &y& Elsevier]

Abstract: Black locust (Robinia pseudoacacia L.) is a widespread alien tree species commonly thought to influence plant assemblages. The aim of this study was to compare the plant diversity between black locust and native recent secondary stands within the European Mediterranean Mountains environmental zone. Spontaneous reforestation was detected by comparing historical aerial photographs and the most recent images. Distributed throughout a 2700km2 hilly and piedmont area, 32 black locust and 32 paired native stands were selected and all vascular plant species were surveyed in a 100m2 area. Analyses of the α and β-diversity were performed separately for six identified plant groups. Despite a clear difference in the tree diversity between the black locust and native recent secondary stands and a homogenisation of the tree layer by the black locust stands, we found only inconsistent hints for homogenisation of the ground-layer vegetation by the black locust stands. There is no evidence to suggest that the presence of black locust in recent secondary stands plays a major role in shaping the diversity of the understory plant groups compared to native stands. [Copyright &y& Elsevier]

Abstract: Modeling the environmental benefits of urban trees requires data which relate crown height, crown diameter, and leaf area to tree age or stem diameter (DBH). Growth prediction curves, that can be derived from the same data, can also be very useful for a better planning, design and development of the urban forest. However, very little information is available on the growth behavior of urban trees, and limited to few species and regional contexts. The aim of this study was to determine the relationships between tree age and various parameters of tree size in order to develop models to predict the growth of the most important species of an urban forest in northeastern Italy. The logarithmic regression model, proposed by and applied by , and other equations were tested in order to obtain the best fit for each species and parameter. All the models provided a better fit for the larger species (Tilia x vulgaris Hayne, Fraxinus angustifolia Vahl., Acer platanoides L.) than for the smaller ones (Prunus cerasifera “pissardi” (Carriere) L.H. Bailey and Lagerstroemia indica L.). The equations for predicting tree sizes and leaf area are presented and applied to compare size and growth 15 and 25 years after planting. According to the models A. platanoides attained the largest average annual DBH growth with values ranging from an average of 1.25cmyears−1 between 0 and 15 years after planting and 1.52cmyears−1 between 15 and 25 years after planting. L. indica showed the smaller DBH growth, ranging from 0.34cmyears−1 in the first period to 0.48cmyears−1 in the second period. 25 years after planting. A. platanoides L. is the tallest species and reaches the largest crown diameter, whith the largest average annual growth, followed by F. angustifolia and Tilia x vulgaris that show similar growth patterns. A comparison with predicted sizes in other studies confirms the need to extend the knowledge to the behavior of more species and more site specific conditions. [Copyright &y& Elsevier]