Pruning Residues Research Articles

Carbon and Nitrogen Mineralization of Common Organic Amendments in Olive Grove Soils

Cover crops (CC), pruning residues (PR), and olive mill pomace (OP) are common amendments to enhance soil quality in olive groves; however, there is limited information on the dynamics of carbon (C) and nitrogen (N) during their decomposition under varying conditions. In this laboratory decomposition experiment, we assessed the C and N mineralization of CC, PR, and OP at application rates of 2 and 5 mg C g−1 in soils with varying organic C levels, both with and without the addition of NO3−. The results indicated that C and N mineralization patterns varied significantly between amendments, although the predicted remaining C after one year was similar for CC and PR (46.7–48.9%) and slightly lower for OP (40.0%). Soil organic carbon level did not affect remaining amendment-C. The addition of N accelerated the decomposition rate of labile C by 15% but slowed down that of the recalcitrant C another 13%, with no significant effect on remaining C. Conversely, increasing the C dose led to a 13% overall reduction in amendment-C mineralization across all combinations of factors. CC decomposition released between −8 and 31% of the amendment-N by day 130, while PR and OP showed net N immobilization. Therefore, CC residues contribute to both C sequestration and N availability, while PR and OP residues can improve N retention in the olive groves while also contributing to C sequestration.

Biomass Resources from Vineyard Residues for the Production of Densified Solid Biofuels in the Republic of Moldova

This paper explores the utilization of biomass resources derived from vineyard residues for producing densified solid biofuels in the Republic of Moldova, with the aim of quantitatively and qualitatively evaluating the residue from vine pruning, focusing on the feasibility of its use as raw material for the production of briquettes and pellets. The methodology includes the analysis of statistical data, as well as experimental investigations conducted at the Scientific Laboratory of Solid Biofuels of the Technical University of Moldova. Waste biomass samples were collected from various vineyards in the different districts of all three regions of the country, focusing on regions with significant plantations. Both quantitative and qualitative aspects of the biomass were assessed, considering the moisture content, calorific value, and ash content. It was found that about 1013 kg/ha of waste biomass is generated from the pruning of technical grape varieties with a net calorific value of 15.6 MJ/kg at a moisture content of 10 wt.% and about 1044 kg/ha with a calorific value of 16.4 MJ/kg from the table ones; both with an average ash content of 3 wt.%. The results indicated that vineyard pruning residues in the Republic of Moldova could provide a substantial biomass source, with an estimated total energy potential of approximately 370 TJ/y (80% located in the Southern region); they also highlighted the need for technological advancements and quality assurance procedures through which to ensure the efficiency and sustainability of biofuel production. The conclusions emphasize the numerous benefits of utilizing viticultural residue, both economically and ecologically, contributing to the sustainable development of the viticulture industry in the Republic of Moldova, as well as environmental protection.

Strategies for the incorporation of organosolv lignin in hydroxypropyl methylcellulose-based films: A comparative study

Organosolv lignin extracted from vine pruning residues was added to hydroxypropyl methylcellulose (HPMC)-based films using three strategies: i) lignin incorporated into the film (lignin-based film), ii) lignin nanoparticles (LNPs) incorporated into the film (LNPs-based film), and iii) lignin coated on HPMC films' surface (lignin-coated film). The films obtained were evaluated in terms of morphology, water barrier and mechanical properties, and antioxidant capacity. Results showed that LNPs incorporation did not affect the films´ water vapour permeability (WVP). Nonetheless, the lignin-based and lignin-coated films improved the water barrier properties of HPMC-based films, achieving a 31.5 and 36 % reduction of WVP, respectively. The morphological evaluation, performed by scanning electron microscopy, revealed films' morphology changes with the lignin incorporation, which was more evident in the lignin-based films. Fourier transform infrared spectroscopy (FTIR) showed minor changes in the film's structure using the different lignin incorporation methods. The mechanical properties were improved, including a significant increase in the tensile strength in the lignin-based and lignin-coated films. All films showed high radical scavenging activity (RSA) after 24 h, with a gradual increase in the lignin-coated films over time. The lignin-coated films showed to be the most promising incorporation strategy to improve the HPMC-based film's properties.

Impact assessment of Zeolite, Ca-bentonite and Biochar amendments on Cd bioavailability and fractions in polluted calcareous soils

The refining of polluted soils by heavy elements is one of the most important environmental policies in industrialized and developing countries. Using adsorbents is a suitable procedure for the immobilization of heavy metals in polluted soils. This study aimed to assess the immobilization of Cadmium (Cd) in polluted calcareous soil affected by the application of organic and inorganic amendments including Biochar (from grape pruning residues) and natural Zeolite and their interaction under wheat cultivation. The treatments used in this study were two amendments of Zeolite and Biochar (from grape pruning wastes) at three levels (0, 1, and 4%) and three levels of Cd contamination (0, 75, and 150 mg/kg soil). A 16-week incubation period was considered for the homogenization of the amendments in soil and wheat was grown according to the standards procedure. At the end of incubation, different fractions of Cd including residual, exchangeable, bonded to organic matter, bonded to carbonate and bonded to iron and manganese. Also available Cd by DTPA and EDTA methods and 1000-grain weight of wheat were measured. The results showed that the highest amount of Cd bound to organic matter was obtained in 4% Biochar treatment to 15 mg/kg. The highest and lowest amounts of Cd extracted with DTPA were obtained in the control one (92 mg/kg) and the level of 4% Biochar (67 mg/kg), respectively. The results showed that increasing the amount of Biochar and Zeolite amendments increased the weight of 1000 grains of wheat in all treatments. According to the results of the study, the use of Biochar and Zeolite reduced the amount of Cd extracted by DTPA ( 82.436 mg/kg) and EDTA (115.605 mg/kg). Finally, the results showed that the use of Biochar and Zeolite has reduced active Cd and its mobility in the soil due to increasing organic and carbonate fractions. Combining biochar and zeolite in soil remediation efforts can enhance their effectiveness in reducing the concentration and mobility of active Cd. The biochar provides a stable carbon matrix for long-term immobilization of Cd, while the zeolite offers additional adsorption capacity and ion-exchange capabilities. This synergistic effect can lead to improved soil quality and reduced environmental risks associated with Cd contamination.

Optimization of industrial-scale composting of dewatered pig slurry and olive mill waste using discarded tennis balls as an inert bulking agent

Material shortages in composting may pose limits or logistical problems in certain regions, which can be addressed with inert and reusable wastes. Very little research has been conducted on the subject of using alternative synthetic wastes as structuring agents to improve composting process parameters. The present work aimed to evaluate the use of used tennis balls (TB) as an inert bulking agent. Composting was carried out in an industrial composting plant with a ternary mixture of olive mill waste, the solid fraction of dewatered pig slurry, urban pruning residues, with the addition of TB as a synthetic bulking agent. Composting process parameters, monitored throughout the composting cycle, showed that TB significantly affected the thermal composting process parameters, with increases in operating temperatures, exothermic index, and mineralization of organic matter. Also, compost properties were seen to be of equal or superior quality at the end of the composting with addition of TB. These are the first experimental results testing the effect of a spherical synthetic reutilized product such as TB on composting processes, which was additionally carried out at an industrial scale, showing that using discarded materials such as used tennis balls can improve the efficiency and economy of composting.

Response of tomato to innovative organo-mineral fertilizers

Organo-mineral fertilizers (OMFs) with low organic carbon (Corg) content have been associated with higher mineral fraction nutrient use efficiency. However, the extraction of peat, which is typically used in these OMFs, from endangered ecosystems causes long-time stored Corg to mineralize and to be released back into the atmosphere as carbon dioxide (CO2). This study analyzes the replacement of peat in OMFs with biowaste materials. These materials, considered organic byproducts that microorganisms and other living things can decompose through composting and aerobic or anaerobic digestion, offer a viable opportunity. This study investigated three stabilized biowastes—green compost (GC) from pruning residues, municipal solid waste compost (MSWC), and manure-based vermicompost (VC)—as the organic matrices for granular OMFs. These matrices were impregnated with dissolved ammonium sulfate and urea and used to coat diammonium phosphate granules. Each biowaste OMF contained 7.5% Corg, 20% mineral N, and 10% mineral P2O5 (OMF20 − 10). Fertilizers with high nutrient concentrations have the advantage of requiring low application volumes, facilitating their application in the field. Biowaste OMFs were compared with peat OMFs with the same Corg-N-P2O5 concentration. Peat and MSWC were also used to create OMFs containing 7.5% Corg, 10% mineral N, and 5% mineral P2O5 (OMF10 − 5). A 75-day tunnel trial was conducted under semi-controlled conditions using tomato plants (Solanum lycopersicum L.) fertilized to an equivalent of 81 mg N kg−1 soil and 18 mg P kg−1 soil. Controls included no fertilization (N0P0) and mineral N and P fertilization (MFNP). The Soil Plant Analysis Development (SPAD) chlorophyll meter and the BBCH (from German Biologische Bundesanstalt, Bundessortenamt und CHemische Industrie) scale as well as the number of shoots were measured over time, as berry and total aboveground yield, N and P uptakes, and N and P use efficiencies (NUE and PUE, respectively) were calculated at harvest. All treatments outperformed the control N0P0 in most indicators. Peat20 − 10 did not have more berry yield than other OMF20 − 10; however, the higher number of shoots indicated a higher potential yield in the event of prolonging the experiment. At the end of 75 days, VC20 − 10 and MSWC20 − 10 showed similar PUE to peat, suggesting that those materials can be used as replacements. In the case of OMF10 − 5, MSWC10 − 5 had yield and N and P uptakes like peat OMFs, confirming the potential use of MSWC as peat replacement even at different nutrient concentrations. This research provides reassuring evidence of the effectiveness of biowaste OMFs, offering a positive outlook for sustainable agriculture. However, their use is not recommendable for short growing seasons.

Characterization of Several Pellets from Agroforestry Residues: A Comparative Analysis of Physical and Energy Efficiency

The use of agroforestry biomass provides several advantages, both from an environmental point of view, in terms of the mitigation of global warming, and in terms of a circular economy for agricultural or agroforestry companies that reuse pruning residues as a source of energy. However, even if the use of energy pellets resulting from the pruning residues of various agroforestry species has excellent potential for the valorization of agricultural by-products, the physicochemical characteristics of these pellets have been scarcely studied by the scientific community. In this context, this study aims to assess the valorization potential of various lignocellulosic material residues produced during agroforestry activities. The objectives of the study include evaluating the chemical and physical characteristics of pellets produced with different mixtures of agroforestry biomass (olive, citrus, black locust, poplar, paulownia, etc.) in order to determine the optimal pellet blend from an energy and physicochemical perspective. The results of this study demonstrate that this comprehensive analysis provides valuable information on the optimization of biomass mixtures for better energy valorization, addressing both compositional and combustion-related challenges. In fact, it is observed that the addition of citrus and olive biomass to the various mixtures increases their energy potential. Furthermore, all of the pellets analyzed are found to possess an adequate and useful durability index (PDI) for their handling during storage and transport operations. This study demonstrates that olive and citrus pruning residues can be used to improve biomasses that have poor suitability in energetic, physical, and chemical terms. Further studies could be useful to understand which specific interaction mechanisms have an influence on emissions in order to optimize mixtures using different biomass sources for sustainable energy production.

Empirical Modelling of Power Requirements in Olive Pruning Residue Shredding: Effects of Varying Moisture Content and Rotary Speeds

Empirical Modelling of Power Requirements in Olive Pruning Residue Shredding: Effects of Varying Moisture Content and Rotary Speeds

Morphological 3D Analysis of PLGA/Chitosan Blend Polymer Scaffolds and Their Impregnation with Olive Pruning Residues via Supercritical CO2.

Natural extracts, such as those from the residues of the Olea europaea industry, offer an opportunity for use due to their richness in antioxidant compounds. These compounds can be incorporated into porous polymeric devices with huge potential for tissue engineering such as bone, cardiovascular, osteogenesis, or neural applications using supercritical CO2. For this purpose, polymeric scaffolds of biodegradable poly(lactic-co-glycolic acid) (PLGA) and chitosan, generated in situ by foaming, were employed for the supercritical impregnation of ethanolic olive leaf extract (OLE). The influence of the presence of chitosan on porosity and interconnectivity in the scaffolds, both with and without impregnated extract, was studied. The scaffolds have been characterized by X-ray computed microtomography, scanning electron microscope, measurements of impregnated load, and antioxidant capacity. The expansion factor decreased as the chitosan content rose, which also occurred when OLE was used. Pore diameters varied, reducing from 0.19 mm in pure PLGA to 0.11 mm in the two experiments with the highest chitosan levels. The connectivity was analyzed, showing that in most instances, adding chitosan doubled the average number of connections, increasing it by a factor of 2.5. An experiment was also conducted to investigate the influence of key factors in the impregnation of the extract, such as pressure (10-30 MPa), temperature (308-328 K), and polymer ratio (1:1-9:1 PLGA/chitosan). Increased pressure facilitated increased OLE loading. The scaffolds were evaluated for antioxidant activity and demonstrated substantial oxidation inhibition (up to 82.5% under optimal conditions) and remarkable potential to combat oxidative stress-induced pathologies.

Determination Size Distribution of Shredded Vineyard Pruning Residues According to Variety

In this study, it was aimed to determine the particle size distribution of vineyard pruning residues shredded with a shredding machine according to grape variety. Pruning residues of three grape varieties, respectively, Boğazkere, Öküzgözü and Şire were used for the experiments. For shredding experiments, a wood chipper machine powered by a 15 HP thermal engine was used. Trials were conducted at three different engine speeds (1500 rpm, 2000 rpm, 2500 rpm). There are 3 shredding blades on the chopper unit of the machine. The blades are driven by gasoline engine with the a belt and pulley system. The study was carried out at three different blade rotation speed. Particle size distribution was determined for each rotation speed and grape variety. Sieves with diameters of 12.5-50 mm were used to calculate the particle size distribution. According to the results, an inverse relationship was obtained between the blade rotation speed and the size length of the shredded branches for all varieties. The ratio of the size and length of the chopped/chopped residues passing through the sieves varied according to the blade speeds. Also, the significant difference were found between varieties (p

Analysis of the environmental and economic performance of common agricultural policy eco-schemes in soil organic carbon sequestration

The Andalusian olive grove in South Spain is employed as a case study to assess the environmental and economic effects of the green architecture (eco-schemes) of the Common Agricultural Policy in relation to low carbon agriculture under different soil management policy scenarios to support more efficient agri-environmental policy making. To do so, we adopted a multidisciplinary approach in which we used: (i) an integrated modelling framework comprising geographic information systems (GIS); (ii) the RothC model; and (iii) a cost-benefit analysis. Results show that eco-schemes provide a significant increase of soil organic carbon (SOC) relative to cross-compliance. Practices involving vegetation covers are more efficient than using pruning residues as mulching. SOC accumulation increases rapidly in the first five-ten years to slow down afterwards. The cost-benefit ratios of eco-schemes policy implementation are higher than one when only SOC is considered. Nonetheless, the inclusion of additional co-benefits has the potential to invert this scenario and enhance policy efficacy. Various insights on optimizing the design and application of eco-scheme efficiency are provided.

Optimizing Agroecological Measures for Climate-Resilient Olive Farming in the Mediterranean.

In order to evaluate the potential of climate change mitigation measures on soil physiochemical properties, an experiment based on the application of five agroecological practices such as the addition of composted olive-mill wastes, recycling pruning residue, cover crops, organic insect manure, and reduced soil tillage, solely or combined, was conducted over two years (2020 to 2022) in a 48-year-old olive plantation. The results showed significant increases in soil water content during the spring and summer periods for the combined treatment (compost + pruning residue + cover crops) (ALL) compared to the control (CONT) by 41.6% and 51.3%, respectively. Also, ALL expressed the highest soil organic matter (4.33%) compared to CONT (1.65%) at 0-10 cm soil depth. When comparing soil nutrient contents, ALL (37.86 mg kg-1) and cover crops (COVER) (37.21 mg kg-1) had significant increases in soil nitrate compared to CONT (22.90 mg kg-1), the lowest one. Concerning exchangeable potassium, ALL (169.7 mg kg-1) and compost (COMP) (168.7 mg kg-1) were higher than CONT (117.93 mg kg-1) at the 0-10 cm soil depth and had, respectively an increase of 100.9% and 60.7% in calcium content compared to CONT. Over the experimental period, the implementation of the five agroecological management practices resulted in enhanced soil fertility. In a long-term Mediterranean context, this study suggests that these sustainable practices would significantly benefit farmers by improving agroecosystem services, reducing reliance on synthetic fertilizers, optimizing irrigation water use, and ultimately contributing towards a circular economy.

Cactus pear pruning residue in agriculture: Unveiling soil-specific responses to enhance water retention

This study examines the effects of incorporating powdered cactus pear pruning waste (PCPPW) on the hydraulic properties of benchmark soils, in line with circular economy principles. The cultivation of cactus pear generates substantial amounts of pruning residues, which offer the potential for nutrient recovery and reuse. Our findings reveal that amending soils with this material has a positive impact on water retention, but it requires a substantial volume, exceeding 20%, which may not be practical for open-field applications. However, this presents promise for the horticultural and floricultural sectors. These results challenge previous assumptions about soil density, plant-available water capacity, and swelling potential, contributing to our understanding of agronomic applications. Notably, the enhancement of drainable water capacity is most significant in less clayey soils, while highly clayey soils experience fewer benefits. These results highlight the importance of considering specific soil conditions when implementing circular economy principles, particularly in soil amendment practices.

Encapsulation of Olive (Olea europaea L.) Pruning Waste Particles by Supercritical CO2 Technology.

Olive leaves (Olea europaea L.) contain a multitude of bioactive compounds such as sterols, carotenes, triterpenic alcohols and phenolic compounds. These compounds have been shown to exhibit antiviral, antioxidant, candida-growth-inhibitory, anticancer, antifungal, anti-inflammatory and antibacterial activities. In this sense, submicron particles from olive leaves with antioxidant activity were precipitated by supercritical antisolvent extraction in a previous work. Moreover, encapsulation enables the delayed release of compounds and avoids the first-step effect in medical therapies. Therefore, this work focused on encapsulation of particles with a certain antioxidant capacity from olive pruning waste using supercritical technology. A variety of experiments were carried out to test how the different operating variables (pressure, temperature and extract-polymer ratio) affect. Morphology was analyzed by SEM microscopy, obtaining encapsulates between 1 and 5 microns in size. The antioxidant capacity was determined by the DPPH assay, with most of the encapsulates having AAI values between 0.5 and 1 (moderate antioxidant capacity). An increase in polyphenol content was observed in the 1:3 ratio tests. The release of the compounds in gastric simulated medium was retarded by the polymeric encapsulation, while in intestinal fluid, the solubility was improved compared to the unencapsulated particles. Overall, the supercritical encapsulation process for the natural extract of olive pruning residues has proven to be effective in obtaining antioxidant particles with different release profiles.

Avocado Pruning Residues for the Formulation of Bio‐Based Polyethylene/Fiber‐Based Biocomposites for Sustainable Food Packaging

AbstractThe extensive use of non‐biodegradable bioplastics and fossil‐based plastics in food packaging presents a significant environmental challenge. Consequently, there has been a growing interest in exploring agricultural biomass as a potential source for formulating biocomposites for packaging due to the substantial amount of lignocellulosic residue generated. This study explores the utilization of avocado pruning residue (APR) for isolating lignocellulose fibers and their application as replacement and reinforcement material for bio‐based polyethylene (BioPE) composites. The results obtained reveal that a concentration of 9% (w/w) of maleic anhydride‐grafted‐polyethylene (MAPE) shows the most effective fiber–polymer interaction, resulting in a significant improvement of 25.47% in the mechanical properties. Biocomposites with varying fiber concentrations, ranging from 10% to 40% (w/w), are prepared and assessed for their macro‐ and micromechanical properties. The results demonstrate a substantial 49% increase in tensile strength and a remarkable 325% enhancement in Young's modulus for biocomposites containing 40% (w/w) fiber content. Furthermore, micromechanical analysis provides insights into the intrinsic strength and modulus of avocado fibers, with values of ≈437 MPa and 33 GPa, respectively. This research contributes to the development of sustainable and eco‐friendly alternatives for food packaging, reducing the reliance on fossil‐based plastics, and promoting the utilization of agricultural waste.

Evaluation of the Energy Use of Pruning Dipteryx alata Trees

Pruning is equivalent to the removal of whole branches or parts, living or dead, of a plant, to promote balance in the development of the species, therefore, the generation of waste portrays an indispensable and ever-present consequence. The residues derived from pruning come from silvicultural treatments and evidently have great potential to be used in energy generation. Briquetting, in addition to its energy advantage and practicality, collaborates with the mitigation of environmental impacts from encouraging the use of renewable energies to reducing the emission of greenhouse gases, as they are strongly recommended for replacing fossil coal. The main objective of this work was to evaluate the possibility, related to quality and productivity, of the energy use of residual biomass from urban pruning of Dipteryx alata, focusing on the production of briquettes, thus encouraging further studies related to native species of the Cerrado and the use of renewable energy. The contents of volatile materials, ash and fixed carbon, higher calorific value, basic and energetic density were determined, and briquettes were produced in a laboratory briquetting machine. The quality of the briquettes was determined through physical-mechanical analyses: apparent density, durability, tensile strength by diametral compression and expansion. The energy density of the biomass had a considerable increase after briquetting, confirming the increase in energy concentration per unit volume in densified materials. Therefore, it was concluded that the use of urban pruning residues of Dipteryx alata proved to be suitable for making briquettes to produce renewable and sustainable energy.

Biological activity of silver nanoparticles synthesized using viticultural waste

This research paper presents a novel approach to the green synthesis of silver nanoparticles (AgNPs) using viticultural waste, allowing to obtain NP dispersions with distinct properties and morphologies (monodisperse and polydisperse AgNPs, referred to as mAgNPs and pAgNPs) and to compare their biological activities. Our synthesis method utilized the ethanolic extract of Vitis vinifera pruning residues, resulting in the production of mAgNPs and pAgNPs with average sizes of 12 ± 5 nm and 19 ± 14 nm, respectively. Both these AgNPs preparations demonstrated an exceptional stability in terms of size distribution, which was maintained for one year. Antimicrobial testing revealed that both types of AgNPs inhibited either the growth of planktonic cells or the metabolic activity of biofilm sessile cells in Gram-negative bacteria and yeasts. No comparable activity was found towards Gram-positives. Overall, pAgNPs exhibited a higher antimicrobial efficacy compared to their monodisperse counterparts, suggesting that their size and shape may provide a broader spectrum of interactions with target cells. Both AgNP preparations showed no cytotoxicity towards a human keratinocyte cell line. Furthermore, in vivo tests using a silkworm animal model indicated the biocompatibility of the phytosynthesized AgNPs, as they had no adverse effects on insect larvae viability. These findings emphasize the potential of targeted AgNPs synthesized from viticultural waste as environmentally friendly antimicrobial agents with minimal impact on higher organisms.

Biochar addition to compost heat recovery systems improves heat conversion yields

Introduction: Compost heat recovery systems (CHRS) represent an emerging technology to recover residual woody biomass from agroforestry and forestry activities and use the heat that is naturally produced during aerobic biodegradation (composting). However, a low oxygen concentration in the gas phase and self-drying and compaction of the compost body often limit efficient oxidation by microbial communities. Woodchip-derived biochar has often been proposed as a bulking agent and improver of water retention and of oxygen accessibility in the composting process, but the literature reporting its effects in the CHRS is scarce.Methods: Here, biochar (average particle size of 10 mm) was added at 10% (on weight basis) to chipped pruning residues into two bench-scale-controlled reactors (0.2 m3), operated in parallel for 57 days.Results and Discussion: The addition of 10% (w/w) biochar to the composting body increased biodegradation yields by approximately 50% and improved oxidation rates over readily biodegradable organic fractions (addition of cheese whey). Temperatures were on average 1.34°C higher, and heat extraction flux was also improved in the presence of biochar (0.3 kW/m3) versus in its absence (0.1 kW/m3). The organic matter mass balance resulted in approximately 50% higher biodegradation yield and improved oxidation rates over readily biodegradable organic fractions. Microbial analysis highlighted a higher concentration of thermophilic species and a lower concentration of well-known pathogenic and antibiotic-resistant genera in the presence of biochar.

Effects of urban tree pruning on ecosystem services performance

Pruning represents the main tree care activity in cities, where it is carried out to reduce wind-break risk, to ensure road visibility, to reduce infrastructure interactions and damages, and last but not least, for aesthetic reasons. However, pruning is also proven to increase tree susceptibility to disease and it can potentially affect their capacity to provide ecosystem services (ES). This study aims to assess the effect of three different life-long pruning scenarios on urban trees PM10 capture and CO2 stock performance. The total carbon balance of twelve tree species (Acer platanoides L., Cedrus spp., Celtis australis L., Cupressus arizonica Greene, Cupressus sempervirens L., Pinus halepensis Mill., Pinus nigra J.F. Arnold, Pinus pinea L. Platanus hybrida Brot., Populus nigra L. var. 'Italica', Quercus ilex L., and Tilia cordata Mill.) was evaluated, including the disposal of the pruning residues of the trees. In all management scenarios studied, pruning represented an opportunity to increase the crown Carbon stock up to 65 %, taking into account the full reestablishment of the crown. The results suggest considering more frequent and less intense ordinary pruning scenarios as a preferable tree management strategy to optimise the tree ES performance and minimise branch dieback occurrence. In addition, the analysis carried out on four different waste wood disposal methods showed that the open dump scenario was the lowest CO2 eq re-emission choice.

Valorization of Olive Leaf Polyphenols by Green Extraction and Selective Adsorption on Biochar Derived from Grapevine Pruning Residues.

Given today's increasingly intensive agriculture, one key problem area considers the valorization and reuse of wastes from food and agricultural production with minimal impact on the environment. Due to its physicochemical characteristics, biochar (BC) derived from grapevine pruning residue has shown considerable potential for use as an adsorbent. High-value phytochemicals found in abundance in the olive leaf (OL) can be employed in many different industrial sectors. The potential application of BC in the removal of specific polyphenolic components from OL extracts has been investigated in the present study. Water, as the most available and greenest of solvents, was investigated as to its use in the extraction of polyphenols, which was carried out by comparing maceration, ultrasound-assisted extraction, and microwave-assisted extraction, considering different temperatures and solid-to-liquid (s/l) ratios. The BC adsorption capacity of selected polyphenols was fitted with both the Langmuir and Freundlich isotherm models. The Freundlich model fitted better relative to OL polyphenols adsorption. Oleuropein was the most abundant compound identified in the extracts, obtaining the highest Kf value (20.4 (mg/g) × (L/g)n) and R2 coefficient (0.9715) in the adsorption on the biochar's surface. The optimum conditions in the dosage experiment suggest the use of 0.5 g of BC using 3 g/L extracts, with an exception for oleuropein and hydroxytyrosol, for which the highest biochar dose (2.5 g) performed better. Considering the compounds' concentrations and the BC dose, BC from grapevine pruning residues demonstrated a potential use in the uptake of specific polyphenols from olive leaves, making it a promising adsorbent for such applications.