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Genetically improved forest reproductive materials are now widely accessible in many European countries due to decades of continuous breeding efforts. Tree breeding does not only contribute to higher-value end products but allows an increase in the rate of carbon capture and sequestration, helping to mitigate the effects of climate change. The usefulness of breeding programmes depends on (i) the relevance of the set of selected traits and their relative weights (growth, drought tolerance, phenology, etc.); (ii) the explicit management of targeted and “neutral” diversity; (iii) the genetic gain achieved; and (iv) the efficiency of transferring diversity and gain to the plantation. Several biological factors limit both operational breeding and mass reproduction. To fully realise the potential of tree breeding, the introduction of new technologies and concepts is pivotal for overcoming these constraints. We reviewed several European breeding programmes, examining their current status and factors that are likely to influence tree breeding in the coming decades. The synthesis was based on case studies developed for the European Union-funded B4EST project, which focused on eight economically important tree species with breeding histories and intensities ranging from low-input breeding (stone pine, Douglas-fir and ash) to more complex programmes (eucalyptus, maritime pine, Norway spruce, poplar, and Scots pine). Tree breeding for these species is managed in a variety of ways due to differences in species’ biology, breeding objectives, and economic value. Most programmes are managed by governmental institutes with full or partial public support because of the relatively late return on investment. Eucalyptus is the only tree species whose breeding is entirely sponsored and managed by a private company. Several new technologies have emerged for both phenotyping and genotyping. They have the potential to speed up breeding processes and make genetic evaluations more accurate, thereby reducing costs and increasing genetic gains per unit of time. In addition, genotyping has allowed the explicit control of genetic diversity in selected populations with great precision. The continuing advances in tree genomics are expected to revolutionise tree breeding by moving it towards genomic-based selection, a perspective that requires new types of skills that are not always available in the institutions hosting the programmes. We therefore recognise the importance of promoting coordination and collaboration between the many groups involved in breeding. Climate change is expected to bring in new pests and diseases and increase the frequency of extreme weather events such as late frosts and prolonged droughts. Such stresses will cause slow growth and mortality, reducing forest productivity and resilience. Most of these threats are difficult to predict, and the time-consuming nature of conventional breeding does not allow for an adequate and timely reaction. We anticipate that most breeding programmes will need to revise their selection criteria and objectives to place greater emphasis on adaptive performance, tolerance to multiple environmental stresses, stability in different environments, and conservation of genetic diversity. Testing breeding materials in a variety of environments, including potentially contrasting climates, will become increasingly important. Climate change may also force the incorporation of new genetic resources that provide new useful adaptations, which may involve the use of new, previously unexplored gene pools or hybridisation, with the enormous challenge of incorporating useful alleles without adding along an unfavourable genetic background. Decision-support tools to help landowners and foresters select the best-performing forest reproductive material in each specific environment could also help reduce the impact of climate change.

In the rich ice polymorphism landscape, ice XVII, metastable at ambient pressure and at temperatures below 130 K, is surely one of the most interesting from both fundamental and technological perspectives due to its porosity, i.e., its capability to repeatedly absorb and desorb molecular hydrogen by dosing the gas at pressures even below the ambient one. Here, owing to this exceptional key feature, we investigate the roto-vibrational dynamics of the H2 molecules trapped in the fully deuterated ice XVII structure. Making use of the high-resolution and brilliance of the TOSCA neutron vibrational spectrometer, combined with high-resolution Raman data, we are able to efficiently distinguish the center-of-mass translational bands from the rotational ones and to study them as a function of the guest filling of the ice structure, unraveling a peculiar behavior for the confined particle in a low-dimensional system. Moreover, we also report the study of the microscopic dynamics of confined nitrogen and oxygen, which are the most abundant molecular species in the atmosphere and are of paramount interest for technological applications. Finally, we show that the ice XVII porosity is a unique feature, especially in the low pressure regime, within the emptied-hydrate phases discovered to date. [ABSTRACT FROM AUTHOR]

In Italy, forest tree crops cover an area of about 100.000 hectares of farmland: more than half are represented by specialized poplar plantations, while the remaining consists mainly of hardwood broadleaves plantations. The profitability of poplar and hardwood broadleaved plantations, assessed by field data collected on a representative number of plantation sites, was evaluated in terms of net present value and equivalent annual value under different levels of wood prices and in presence or absence of financial public incentives. Under current market conditions the investment in specialized poplar plantations is usually positive, even without subsidies. On the contrary, hardwood broadleaves plantations usually do not provide positive financial results without public incentives, while better financial results can be obtained by polycyclic plantations including both hardwood broadleaves (medium-long rotation) and hybrid poplar (short rotation) on the same parcel.

This technical note describes a quick methodology to classify the phytodepurative potential of riparian forest stands. Some municipalities located within landscapes characterized by both intensive agricultural and industrial activities in Central Italy are considered as test areas. Starting from the on-screen interpretation of high-resolution digital aerial orthophotos, supported by accurate ground surveys and GIS operations, it has been possible to map the riparian forest stands and classify each of them based on factors representing their phytodepurative potential. The proposed mapping process, feasible and easily replicable, provides a support tool for analysis and planning related to phytoremediation and/or to identify conservation and environmental management priorities and, depending on the goals of the phytoremediation objectives, to define where to locate eventual specific technical interventions.

The present paper investigates the influence of thermo-vacuum treatment at 170, 190 and 210 °C on the mechanical and physical properties of poplar wood rotary-cut veneers obtained from two different poplar clones (’I-214’ and ’Lena’). The modulus of rupture in bending was determined according to a method derived from European Standard EN-310 and previously validated by the authors, while the density was determined on the basis of EN-323. With both clones no significant decrease was recorded either in bending strength or in density with treatment temperatures up to 190 °C. On the contrary, at 210 °C a highly significant decrease in modulus of rupture (’I-214’: -18%; ’Lena’: -15%) was recorded; the density showed a similar, though lower, trend (’I-214’: -5 %; ’Lena’: -8.5 %).