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Abstract Cutting costs in farms is the main concern for several stakeholders, specifically for farmers. Reducing energy costs allows for, at the very least, two relevant outcomes, one concerning increases in the net farm income and the other relating to the environment and the promotion of more sustainable farming and rural development. In turn, the agricultural sector may itself be a relevant source of renewable and clean energies. Considering these motivations, this research/study has intended to explore the concept of agricultural energy, highlighting the main insights from literature, and to stress the relationships between this concept and relevant farming indicators. The findings obtained may provide interesting support for the several related stakeholders, namely, policymakers, farmers and researchers. To achieve these objectives, literature available on scientific platforms was explored and statistical relationships were established, through econometric approaches (allowing for spatial effects), between structural characteristics from farms in the European Union. The findings reveal that the several instruments within the Common Agricultural Policy (CAP) should further address the relationships between financial support and sustainability. For example, it could be interesting to index the direct payments from the 1st CAP Pillar with farm indicators that consider dimensions related with the efficiency and savings in costs. In the current context, it is possible to increase the output and area with energy cost growths of 0.423 and 0.375% points, respectively, and increase the total crops output/ha growth and the utilised agricultural area with energy costs/ha growth of 0.243 and −0.225% points, respectively.

Plant communities, through species richness and composition, strongly influence soil microorganisms and the ecosystem processes they drive. To test the effects of other plant community attributes, such as the identity of dominant plant species, evenness, and spatial arrangement, we set up a model mesocosm experiment that manipulated these three attributes in a full factorial design, using three grassland plant species (Anthoxanthum odoratum, Plantago lanceolata, and Lotus corniculatus). The impact of the three community attributes on the soil microbial community structure and functioning was evaluated after two growing seasons by ester-linked phospholipid fatty-acids analysis, substrate-induced respiration, basal respiration, and nitrogen mineralization and nitrification rates. Our results suggested that the dominant species identity had the most prevalent influence of the three community attributes, with significant effects on most of the measured aspects of microbial biomass, composition and functioning. Evenness had no effects on microbial community structure, but independently influenced basal respiration. Its effects on nitrogen cycling depended on the identity of the dominant plant species, indicating that interactions among species and their effects on functioning can vary with their relative abundance. Systems with an aggregated spatial arrangement had a different microbial community composition and a higher microbial biomass compared to those with a random spatial arrangement, but rarely differed in their functioning. Overall, it appears that dominant species identity was the main driver of soil microorganisms and functioning in these model grassland communities, but that other plant community attributes such as evenness and spatial arrangement can also be important.

On behalf of the EURAF2020 Scientific and Organizing Committees, we are very pleased to introduce the rich collection of research on agroforestry illustrated in this book of abstracts and presented within the 5° European Agroforestry Conference. Unfortunately, as we all know, the COVID-19 pandemic has forced us to meet only remotely, despite all the efforts of our local and national organizers to hold the conference in presence. We are conscious about the completely different dimension, which does not allow participants to meet, discuss and live the conference supported by an environment socially vibrant and rich of cross-cultural stimuli as the real Sardinia can offer. Nevertheless, in accordance with the mission of the European Agroforestry Federation, EURAF, to promote agroforestry knowledge, we wish to support the sharing of data presented and solicit a fruitful scientific confrontation on agroforestry issues. This book is the result of a long and rigorous work performed by the authors (about 230 abstracts sent from 5 continents and 37 countries) and members of the Scientific Committee. The book will be one of the tools supporting such confrontation we are glad to foster from the heart of the Mediterranean.

AbstractClimate change will affect semiarid ecosystems through severe droughts that increase the competition for resources in plant and microbial communities. In these habitats, adaptations to climate change may consist of thinning—that reduces competition for resources through a decrease in tree density and the promotion of plant survival. We deciphered the functional and phylogenetic responses of the microbial community to 60 years of drought induced by rainfall exclusion and how forest management affects its resistance to drought, in a semiarid forest ecosystem dominated byPinus halepensisMill. A multiOMICapproach was applied to reveal novel, community‐based strategies in the face of climate change. The diversity and the composition of the total and active soil microbiome were evaluated by 16SrRNAgene (bacteria) andITS(fungal) sequencing, and by metaproteomics. The microbial biomass was analyzed by phospholipid fatty acids (PLFAs), and the microbially mediated ecosystem multifunctionality was studied by the integration of soil enzyme activities related to the cycles of C, N, and P. The microbial biomass and ecosystem multifunctionality decreased in drought‐plots, as a consequence of the lower soil moisture and poorer plant development, but this decrease was more notable in unthinned plots. The structure and diversity of the total bacterial community was unaffected by drought at phylum and order level, but did so at genus level, and was influenced by seasonality. However, the total fungal community and the active microbial community were more sensitive to drought and were related to ecosystem multifunctionality. Thinning in plots without drought increased the active diversity while the total diversity was not affected. Thinning promoted the resistance of ecosystem multifunctionality to drought through changes in the active microbial community. The integration of total and active microbiome analyses avoids misinterpretations of the links between the soil microbial community and climate change.

Miscanthus is a high yielding bioenergy crop. In this study we used acid presoaking, wet explosion, and enzymatic hydrolysis to evaluate the combination of the different pre-treatment methods for bioethanol production with Miscanthus. Acid presoaking is primarily carried out in order to remove xylose prior to wet explosion. The acid presoaking extracted 63.2% xylose and 5.2% glucose. Direct enzymatic hydrolysis of the presoaked biomass was found to give only low sugar yields of 24-26% glucose. Wet explosion is a pre-treatment method that combines wet-oxidation and steam explosion. The effect of wet explosion on non-presoaked and presoaked Miscanthus was investigated using both atmospheric air and hydrogen peroxide as the oxidizing agent. All wet explosion pre-treatments showed to have a disrupting effect on the lignocellulosic biomass, making the sugars accessible for enzymatic hydrolysis. The combination of presoaking, wet explosion, and enzymatic hydrolysis was found to give the highest sugar yields. The use of atmospheric air gave the highest xylose yield (94.9% xylose, 61.3% glucose), while hydrogen peroxide gave the highest glucose yield (82.4% xylose, 63.7% glucose).

Abstract The methane productivity of manure in terms of volatile solids (VS), volume and livestock production was determined. The theoretical methane productivity is higher in pig (516 l kg −1 VS ) and sow (530 l kg −1 VS ) manure than in dairy cattle manure (469 l kg −1 VS ) , while the ultimate methane yield in terms of VS is considerably higher in pig (356 l kg −1 VS ) and sow manure (275 l kg −1 VS ) than in dairy cattle manure (148 l kg −1 VS ) . Methane productivity based on livestock units (LU) shows the lowest methane productivity for sows (165 m 3 CH 4 LU −1 ) , while the other animal categories are in the same range (282– 301 m 3 CH 4 LU −1 ). Pre-treatment of manure by separation is a way of making fractions of the manure that have a higher gas potential per volume. Theoretical methane potential and biodegradability of three types of fractions deriving from manure separation were tested. The volumetric methane yield of straw was found to be higher than the yield from total manure and the solid fractions of manure, due to the higher VS content, and hence the use of straw as bedding material will increase the volumetric as well as the livestock-based methane productivity.

Abstract The industry of mushroom cultivation uses a wide variety of lignocellulosic waste and is considered a very efficient way to recycle agro-residues and to produce food. This activity generates tons of spent mushroom substrate (SMS) every year, causing a significant disposal challenge. The SMS is a useful resource for the generation of biogas, since raw material is digested by the metabolism of fungi, performing as a pre-treatment, thus facilitating the subsequent anaerobic digestion and increasing the yield of methane production. Forty-one species of fungi have been used as pre-treatment in different types of residues; among them, 13 were cultivated mushrooms. The potential production of methane using SMS pre-treated with cultivated mushrooms should be added to the list of other common residues used, such as food/vegetable waste and pig manure. Biogas can be used as fuel, and the residues from biogas can be used as fertilizers for food crops. These productive activities can be integrated in a virtuous circle of reuse of organic resources; in which the waste of one activity is used as a substrate for another activity. Given the huge amount of SMS produced, we propose to integrate it into a virtuous circle of resource reutilization for energy generation, particularly as a viable substrate for biogas generation.

Sustainable agriculture leads today to important questions about the diversification of agricultural production and sources of income for farmers, the use of rural and arable land for food and non-food crops, the contribution of agriculture to climate change fighting and the supply of renewable energy. Bioenergy from agriculture is at the heart of these concerns, integrating sustainable development key components: environment and climate change, energy economics and energy supply, agriculture, rural and social development. The lack of primary and reliable data on bioenergy externalities from agriculture and the lack of decision-making tools are important non-technological barriers to the development of bioenergy from agriculture on a large scale, and, consequently, to the achievement of the national and regional objectives of sustainable development with respect to greenhouse gas mitigation, secure and diversified energy supply, rural development and employment and the future of agriculture. Furthermore, the recent worldwide controversies about transport biofuels, food shortages and increasing prices have demonstrated the urgent need for sustainability criteria applied to biofuels and bioenergy. Within this current sustainable development framework, a project entitled TEXBIAG integrating experts from 4 research institutions is financed by the Belgian Science Policy. The final objective of this project is to lead to an actual and significant contribution of bioenergy from agriculture to the mitigation of greenhouse gas emissions, to a secure and diversified energy supply and to farmers' incomes and rural development. To reach this final objective, the project develops three specific tools: (1) a database of primary quantitative data related to environmental and socio-economic impacts of bioenergy from agriculture integrating biomass logistics; (2) a mathematical model monetizing bioenergy externalities from agriculture; and (3) a prediction tool assessing the impacts of political decisions made in the framework ofthe development of bioenergy from agriculture on different economic sectors (energy, agriculture, industry, and environment). An integrated interface tool will be programmed where access to and update of the three tools will be prepared. The project methodology will be conducted for a given number of scenarios with sensitivity analysis wherever possible. The three main target groups that will benefit from the project are: the government officials and policy makers in the field of agriculture, energy and environment in Belgium and its two main regions, the small, medium and large energy companies and the agricultural sector