Forest and agricultural biomass are important sources of renewable and sustainable fuel for energy production. Their increasing consumption is mainly related to the increase in global energy demand and fossil fuel prices but also to the limited availability of petroleum and the lower environmental impact of these biomass compared with other non-renewable fuels. In particular, the pellet sector has seen important developments in terms of both production and the number of installed transformation plants. In addition, pellet production from non-woody biomass is increasing in importance. One of the fundamental aspects for the correct and sustainable use of a biofuel is evaluation of its quality. This is even more important when dealing with pellet production, considering the broad spectrum of possible raw materials for pelletizing. Considering the significant number of papers dealing with pellet quality evaluation and improvement in the last decade, this review aims to give the reader an overall view of the most current knowledge about this large and interesting topic. We focused on pellets of agricultural and forestry origin and analyzed papers regarding the specific topic of pellet quality evaluation and improvement from the last five years (2016–2020). In particular, the review findings are presented in the following order: the influence of different agro-forest management systems on pellet quality; analysis of pellets from pure feedstocks (no blending or binders); the influence of blending and binders on pellet quality; and the influence of pre and post treatments. Finally, a brief discussion about actual research lacks in this topic and the possibilities for future research are presented. It is important to underline that the present review is focused on the influence of the biomass characteristics on pellet quality. The effects of the process parameters (die temperature, applied pressure, holding time) on pellet features are not considered in this review, because that is another very large topic deserving a dedicated paper.

The sustainable production of renewable energy is a key topic on the European community’s agenda in the next decades. The use of residuals from agriculture could not be enough to meet the growing demand for energy, and the contribution of vegetable oil to biodiesel production may be important. Moreover, vegetable oil can surrogate petroleum products in many cases, as in cosmetics, biopolymers, or lubricants production. However, the cultivation of oil crops for the mere production of industrial oil would arise concerns on competition for land use between food and non-food crops. Additionally, the economic sustainability is not always guaranteed, since the mechanical harvesting, in some cases, is still far from acceptable. Therefore, it is difficult to plan the future strategy on bioproducts production from oil crops if the actual feasibility to harvest the seeds is still almost unknown. With the present review, the authors aim to provide a comprehensive overview on the state of the art of mechanical harvesting in seven herbaceous oil crops, namely: sunflower (Heliantus annuus L.), canola (Brassica napus L.), cardoon (Cynara cardunculus L.), camelina (Camelina sativa (L.) Crantz), safflower (Carthamus tinctorius L.), crambe (Crambe abyssinica R. E. Fr.), and castor bean (Ricinus communis L.). The review underlines that the mechanical harvesting of sunflower, canola and cardoon seeds is performed relying on specific devices that perform effectively with a minimum seed loss. Crambe and safflower seeds can be harvested through a combine harvester equipped with a header for cereals. On the other hand, camelina and castor crops still lack the reliable implementation on combine harvesters. Some attempts have been performed to harvest camelina and castor while using a cereal header and a maize header, respectively, but the actual effectiveness of both strategies is still unknown.

Reducing potential soil damage due to the passing of forest machinery is a key issue in sustainable forest management. Limiting soil compaction has a significant positive impact on forest soil. With this in mind, the aim of this work was the application of precision forestry tools, namely the Global Navigation Satellite System (GNSS) and Geographic Information System (GIS), to improve forwarding operations in hilly areas, thereby reducing the soil surface impacted. Three different forest study areas located on the slopes of Mount Amiata (Tuscany, Italy) were analyzed. Extraction operations were carried out using a John Deere 1410D forwarder. The study was conducted in chestnut (Castanea sativa Mill.) coppice, and two coniferous stands: black pine (Pinus nigra Arn.) and Monterey pine (Pinus radiata D. Don). The first stage of this work consisted of field surveys collecting data concerning new strip roads prepared by the forwarder operator to extract all the wood material from the forest areas. These new strip roads were detected using a GNSS system: specifically, a Trimble Juno Sb handheld data collector. The accumulated field data were recorded in GIS Software Quantum GIS 2.18, allowing the creation of strip road shapefiles followed by a calculation of the soil surface impacted during the extraction operation. In the second phase, various GIS tools were used to define a preliminary strip road network, developed to minimize impact on the surface, and, therefore, environmental disturbance. The results obtained showed the efficiency of precision forestry tools to improve forwarding operations. This electronic component, integrated with the on-board GNSS and GIS systems of the forwarder, could assure that the machine only followed the previously-planned strip roads, leading to a considerable reduction of the soil compaction and topsoil disturbances. The use of such tool can also minimize the risks of accidents in hilly areas operations, thus allowing more sustainable forest operations under all the three pillars of sustainability (economy, environment and society).

Among the species currently cultivated for industrial vegetable oil production, castor could be a good candidate for future investments due to the good resistance to pests, tolerance to drought, and suitability for marginal lands cultivation. In addition, the production of castor oil from Ricinus generates a large quantity of press cake, husks, and crop residues that, in a framework of bioeconomy, could be used as by-products for different purposes. Using a case study approach, the work presents results of the environmental impact assessment and economic feasibility of the production of castor oil from two different castor hybrids comparing four by-products management scenarios and two harvesting systems (manual vs. mechanical). Castor hybrid C-856 harvested manually and that involved only the soil incorporation of press cake obtained by the oil extraction resulted as the most sustainable. The hybrid C-1030 resulted as more profitable than C-856 when harvested with the combine harvester. The ratio between gross margin and GWP emissions was applied to calculate the economic performance (gross margin) per unit of environmental burden. Findings showed that Sc1B scenario in case of C-856 cultivar hybrid had a better ratio between economic performance and greenhouse gas (GHG) emitted into the atmosphere (€3.75 per kg CO₂eq).

This paper focused on eggs enriched with omega-3-fatty acids with the aim of understanding if functional eggs were of interest to Italian consumers, and analyzing which characteristics of table egg quality, consumers’ attitudes and socio-demographic characteristics affect the consumers’ willingness to pay (WTP) a premium price for eggs enriched with omega-3-fatty acids. We performed an online survey on 312 Italian consumers. The analysis was based on the Tobit regression model. The findings showed that unmarried females were more willing to pay a premium price for functional eggs than male consumers. Furthermore, the probability of showing a higher WTP for functional eggs increased among consumers reporting a higher income. Moreover, the WTP for functional eggs increased with the growing importance that people attributed to items such as the size of eggs, rearing type, feed given to chickens, and the provenience and brand of eggs. These results suggested that consumers need to have clear information about functional eggs. As expected, WTP for functional eggs decreased with increasing neophobia and food techno-neophobia factors. In conclusion, the findings showed an interesting potential for eggs enriched with omega-3-fatty acids, which seems to be a product with high possibility to be greatly appreciated on the market, especially if accompanied by a good, informative campaign for increasing people’s knowledge level.

Fine roots are an important component of forest soil as they play a key role in fundamental processes like plant nutrition and water supply. As with all the features of forest soil, the compaction related to the forest operations and, in particular, to the wood extraction via ground‐based technologies could lead to a significant impact on the presence of fine roots in the soil affected by the passage of the machines. Considering the lack of a review, we used a meta‐analytic approach to synthesise effect sizes of ground‐based extraction technologies affecting the presence of fine roots in the soil, using a multivariate mixed‐effects meta‐analytic model. The obtained results revealed that the presence of fine roots in the soil affected by the passage of the machines was significantly reduced by both skidding (g = −1.23, 95%CI ‐1.87, −0.60) and forwarding (g = −1.37, 95%CI ‐2.01, −0.74). Due to the higher soil compaction caused by forwarding, this method had a marginally but statistically significant greater impact than skidding. We further confirmed the hypothesis that soil compaction and the presence of fine roots were strongly correlated, with the latter being greatly reduced in compacted soils characterised by higher bulk density. What is more, even more than 20 years after a harvesting intervention, the presence of fine roots was significantly lower in both strip roads (forwarding) and skid trails (skidding) as compared to areas which were not impacted by the machine passage. This shows that fine roots are particularly vulnerable to forest operations. On the other hand, the majority of the trails in the database used for the meta‐analysis were created in countries that favour the creation of a small number of widely used trails. Therefore, it would be scientifically valuable to do a comparative evaluation in various forestry contexts, such as in the Mediterranean area, where the development of the forest trails network is oriented on creating a large number of trails with low traffic volumes. Because machinery‐induced soil compaction is the major driver of the decrease in fine roots in skid trails and strip roads, both the application of best management practices as well as of a smarter planning of the trail network to limit soil compaction are strongly recommended. Both applications are highly recommended to be used in the planning phase and in the practical implementation of logging activities.