• SDSN - Greece
• 2022-2022close
• Publications close

The exploitation of industrial crops for the production of ligno-cellulosic compounds and vegetable oil on marginal lands relies on efficient harvesting and logistics’ strategies. The present deliverable goes through the difficulties encountered from harvesting to dispatchment of indrustrial crops highlighting prons and cons of the currently available technologies to improve the whole value chain in the following categories: lignocellulosic crops (fiber, herbaceous perennial and Short-Medium Rotation Coppice (SRC-MRC)) and oil crops. The two sections are indipendently investigated focusing on harvesting and densifiction of the biomass to reduce cost and increase profitability. The information provided within the present document was gathered from experimental data collected on fields, from literature review and background knowledge gained from collaboration in previous research projects. Regarding fiber crop (in particular hemp) it is possible to say that there are several solutions available to harvest this species, which should be properly selected according to the crop features and to the aim of the cultivation, i.e. fiber and seed-fiber. Focusing on lignocellulosic crops, the present deliverable focused mainly on miscanthus, describing the possible alternative solutions which are generally based on cutting the plants and densify them through chipping and/or baling. Harvesting systems for SRC and MRC have been instead experiencing a substantial change in the last years, shifting from dedicated systems for biomass harvesting and densification to semi or fully mechanized harvesting approaches, derived from forestry sector, in order to produce fiber wood from the main stem and biomass from branches and tops. Finally, concerning oil crops, it is possible to say that, among the investigated ones, camelina and castor can efficiently be harvested with conventional combine harvesters equipped with cereal and sunflower header respectively. Castor bean harvesting is instead still a great challenge, indeed the present deliverable highlights how a sunflower header is a better option than a cereal one, but however many concerns are still present regarding seed loss and quality of the collected product.

Soil organic matter (SOM) stocks are crucial for soil fertility and food provision and also contribute to climate change adaptation and mitigation. However, assessing SOM changes in cropping systems is difficult due to the varying quantity and quality of input data. SOM processes have been described by several models, but these are complex and require high amounts of input data. In this work, we identified and selected frameworks that simulate SOM pools and stocks as well as the effects of different management practices. We also required that the frameworks be easily accessible for farm-related end users and require limited and accessible amounts of input data. In all, six frameworks met our inclusion criteria: SOCRATES (Soil Organic Carbon Reserves and Transformations in EcoSystems), CCB (CANDY and-Carbon Balance), AMG, CENTURY, CQESTR, and RothC (Rothamsted Carbon Model). We collected information on these frameworks and compared them in terms of their accessibility, the model time steps used, the nutrient cycles included in the simulation, the number of SOM pools, and the agricultural management options included. Our results showed that CCB was the most robust of the frameworks considered, while AMG, CQESTR, and RothC performed the least well. However, all frameworks have strengths which may match the specific requirements and abilities of individual users.

Assessing the sustainability of agri-food chains is challenging for several reasons. It should account for the impacts on environmental, social, and economic wellbeing simultaneously, considering both the individual links in the chain and the chain as a whole. The primary aim of this study is to assess the conditions for meeting the sustainability criteria of a legume-based agri-food chain in Slovenia. Therefore, a quantitative sustainability assessment methodology was developed, using a multi-stakeholder approach, which upgraded the traditional SWOT (strengths, weaknesses, opportunities, and threats) analysis. Our approach, called ‘Multi-SWOT’, aggregates the SWOT table inputs identified by stakeholders into factors, themes and focus areas, according to their importance for the agri-food chain, for each sustainability pillar, and links in the chain. By accounting for the relative number of incentives (beneficial factors) and barriers (constraint factors) we identified those factors that enhance the sustainability of the Slovenian legume-based agri-food chain and the factors jeopardising it. The incorporation of multi-stakeholder perspectives presents an innovative approach that adds value to a standard SWOT analysis. The study serves as a guide to help decision-makers better understand the multidimensionality of sustainability and identify effective activities to support and strengthen the current legume agri-food chain in Slovenia.

The use of composite materials has grown exponentially in transport structures due to their weight reduction advantages, added to their capability to adapt the material properties and internal micro-structure to the requirements of the application. This flexibility allows the design of highly efficient composite structures that can reduce the environmental impact of transport, especially if the used composites are bio-based. In order to design highly efficient structures, the numerical models and tools used to predict the structural and material performance are of great importance. In the present paper, the authors propose a multi-objective, multi-scale optimization procedure aimed to obtain the best possible structure and material design for a given application. The procedure developed is applied to an aircraft secondary structure, an overhead locker, made with a sandwich laminate in which both, the skins and the core, are bio-materials. The structural multiscale numerical model has been coupled with a Genetic Algorithm to perform the optimization of the structure design. Two optimization cases are presented. The first one consists of a single-objective optimization problem of the fibre alignment to improve the structural stiffness of the structure. The second optimization shows the advantages of using a multi-objective and multi-scale optimization approach. In this last case, the first objective function corresponds to the shelf stiffness, and the second objective function consists of minimizing the number of fibres placed in one of the woven directions, looking for a reduction in the material cost and weight. The obtained results with both optimization cases have proved the capability of the software developed to obtain an optimal design of composite structures, and the need to consider both, the macro-structural and the micro-structural configuration of the composite, in order to obtain the best possible solution. The presented approach allows to perform the optimisation of both the macro-structural and the micro-structural configurations. This work has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 690638, from the Special Research Plan on Civil Aircraft of Ministry for Industry and Information of the People’s Republic of China (MIIT) un- der Grant No MJ-2015-H-G-103, and from the Spanish Ministerio de Economia y Competividad through the project MAT2014-60647-R, Multi-scale and multi-objective optimization of composite laminate structures (OMMC). The authors also acknowledge the Severo Ochoa Centre of Excellence (2019–2023), which financially supported this work under the grant CEX2018-000797-S funded by MCIN/AEI/10.13039/501100011033. Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables Objectius de Desenvolupament Sostenible::13 - Acció per al Clima Peer Reviewed

Our goal was to understand the mechanisms behind the impact of nutrient enrichment at intermediate distances from aquaculture on the interactions of a subtidal macroalgae community with its main grazer, the sea urchin Paracentrotus lividus. We assessed the diversity and cover of the macroalgal community, the abundance and biometrics of the sea urchins, the carbon and nitrogen elemental and isotopic compositions, and their metabolome in two stations, at an intermediate distance (station A) and away (station B) from a fish cage facility in the Aegean Sea (Greece), during the warm and cold seasons. The nutrient input at station A favored a shift to a macroalgal assemblage dominated by turf-forming species, depleted of native-erected species and with a higher abundance of invasive algae. A stable isotope analysis showed fish-farm-associated nitrogen enrichment of the macroalgae and trophic transfer to P. lividus. A decrease in metabolites related to grazing, reproduction, and energy reserves was found in P. lividus at station A. Furthermore, the metabolomic analysis was able to pinpoint stress in P. lividus at an intermediate distance from aquaculture. The chosen combination of traditional ecology with omics technology could be used to uncover not only the sublethal effects of nutrient loading but also the pathways for species interactions.

The dynamics across different scales in the stable atmospheric boundary layer has been investigated by means of two metrics, based on instantaneous fractal dimensions, and grounded in dynamical systems theory. The wind velocity fluctuations obtained from data collected during the CASES-99 experiment were analyzed to provide a local (in terms of scales), and an instantaneous (in terms of time) description of the fractal properties and predictability of the system. By analyzing the phase space projections of the continuous turbulent, intermittent and radiative regimes, a progressive transformation, characterized by the emergence of multiple low-dimensional clusters embedded in a high-dimensional shell and a 2-lobe mirror symmetrical structure of the inverse persistence, have been found. The phase space becomes increasingly complex and anisotropic as the turbulent fluctuations become uncorrelated. The phase space is characterized by a three-dimensional structure for the continuous turbulent samples in a range of scales compatible with the inertial sub-range, where the phase space-filling turbulent fluctuations dominate the dynamics, and is low-dimensional in the other regimes. Moreover, lower dimensional structures present a stronger persistence than the higher dimensional structures. Eventually, all samples recover a three-dimensional structure and higher persistence level at large scales, far from the inertial sub-range. The two metrics obtained in the analysis can be considered as proxies for the decorrelation time and the local anisotropy in the turbulent flow. International audience

Green synthesis of gold nanoparticles (AuNPs) using microorganisms has been generally studied aiming for high-yield production and morphologies appropriated for various applications, such as bioremediation, (bio)sensors, and (bio)catalysis. Numerous approaches showed the individual effect of factors influencing the synthesis of AuNPs with limited analysis of the governing factors enhancing the production and desired quality of the precipitates. This study proposes a fractional-factorial design to investigate the simultaneous influence of seven environmental factors (cell concentration, temperature, anoxic/oxic conditions, pH, gold concentration, electron donor type, and bacterial species) on the recovery yield and synthesis of targeted AuNPs. Various sizes and morphologies of the AuNPs were obtained by varying the environmental factors studied. The factors with significant effects (i.e., 0.2 mM Au and pH 5) were selected according to statistical analysis for optimal removal of 88.2 ± 3.5% of gold and with the production of valuable 50 nm AuNPs, which are known for their enhanced sensitivity. Implications of the cytochrome-C on the bacterial mechanisms and the provision of electron donors via an electrochemical system are further discussed. This study helps develop gold recovery and nanoparticle synthesis methods, focusing on the determining factor(s) for efficient, low-cost, green synthesis of valuable materials.