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- ItemOptions for optimizing the drying process and reducing dry matter losses in whole-tree storage of poplar from short-rotation coppices in Germany(Basel : MDPI, 2020) Pecenka, Ralf; Lenz, Hannes; Hering, ThomasFor sustainable production of wood in short-rotation coppices and agroforestry systems, it is necessary to optimize the storage processes to achieve low dry matter losses together with low-cost drying. The harvesting of the trees can be carried out very efficiently with modified forage harvesters or tractor-powered mower-chippers. The wood chips produced can be dried naturally at low cost in open-air piles. However, this type of storage is connected with high dry matter losses of up to about one fourth in the course of seven-month storage. Although harvesting whole trees is connected with significantly higher costs, lower dry matter losses are to be expected from storing the trees in piles. Consequently, in this study, the storage and drying behavior of poplar under different German weather conditions and depending on the structure of the storage piles has been examined in detail. After a seven-months storage period, the trees still displayed moisture contents of 41–44% following an initial moisture content of 56% but achieved very low dry matter losses of only 4–7%. Moisture contents of 35–39% could only be achieved in October after a further two-months drying period under favorable weather conditions. All storage piles were built up on approximately 30 cm high support timbers for better ventilation. Additionally, covering the ground with a fleece did not have any influence on the drying behavior, nor did different pile heights. Smaller tree trunk diameters are not only connected with a higher share of bark or ash, but also thinner trunks tend to become damp again more quickly after rainfall. That is why whole-tree storage is suitable above all for medium or longer rotation periods with which, under favorable conditions, the higher harvesting costs can be compensated by a higher wood chip quality and lower storage losses.
- ItemEstablishment of a Laboratory Scale Set-Up with Controlled Temperature and High Humidity to Investigate Dry Matter Losses of Wood Chips from Poplar during Storage(Basel : MDPI, 2022) Hernandez-Estrada, Albert; Pecenka, Ralf; Dumfort, Sabrina; Ascher-Jenull, Judith; Lenz, Hannes; Idler, Christine; Hoffmann, ThomasThe aim of this work was to improve the understanding of dry matter losses (DML) that occur in wood chips during the initial phase of storage in outdoor piles. For this purpose, a laboratory scale storage chamber was developed and investigated regarding its ability to recreate the conditions that chips undergo during the initial phase of outdoor storage. Three trials with poplar Max-4 (Populus maximowiczii Henry Populus nigra L.) chips were performed for 6–10 weeks in the storage chamber under controlled temperature and assisted humidity. Two different setups were investigated to maintain a high relative humidity (RH) inside the storage chamber; one using water containers, and one assisted with a humidifier. Moisture content (MC) and DML of the chips were measured at different storage times to evaluate their storage behaviour in the chamber. Additionally, microbiological analyses of the culturable fraction of saproxylic microbiota were performed, with a focus on mesophilic fungi, but discriminating also xerophilic fungi, and mesophilic bacteria, with focus on actinobacteria, in two trials, to gain a view on the poplar wood chip-inhabiting microorganisms as a function of storage conditions (moisture, temperature) and time. Results show that DML up to 8.8–13.7% occurred in the chips within 6–10 storage weeks. The maximum DML were reached in the trial using the humidifier, which seemed a suitable technique to keep a high RH in the testing chamber, and thus, to analyse the wood chips in conditions comparable to those in outdoor piles during the initial storage phase.
- ItemEffect of 1-Methyl Cyclopropane and Modified Atmosphere Packaging on the Storage of Okra (Abelmoschus esculentus L.) : Theory and Experiments(Basel : MDPI, 2020) Kanwal, Rabia; Ashraf, Hadeed; Sultan, Muhammad; Babu, Irrum; Yasmin, Zarina; Nadeem, Muhammad; Asghar, Muhammad; Shamshiri, Redmond R.; Ibrahim, Sobhy M.; Ahmad, Nisar; Imran, Muhammad A.; Zhou, Yuguang; Ahmad, RiazOkra possesses a short shelf-life which limits its marketability, thereby, the present study investigates the individual and combined effect of 1-methylcyclopropene (1-MCP) and modified atmosphere packaging (MAP) on the postharvest storage life of okra. The treated/ untreated okra samples were stored at ambient (i.e., 27 °C) and low (i.e., 7 °C) temperatures for eight and 20 days, respectively. Results revealed that the 1-MCP and/or MAP treatment successfully inhibited fruit softening, reduction in mucilage viscosity, and color degradation (hue angle, ∆E, and BI) in the product resulting in a longer period of shelf-life. However, MAP with or without 1-MCP was more effective to reduce weight loss in okra stored at both ambient and cold storage conditions. Additionally, ascorbic acid and total antioxidants were also retained in 1-MCP with MAP during cold storage. The 1-MCP in combination with MAP effectively suppressed respiration rate and ethylene production for four days and eight days at 27 °C and 7 °C temperature conditions, respectively. According to the results, relatively less chilling injury stress also resulted when 1-MCP combined with MAP. The combined treatment of okra pods with 1-MCP and MAP maintained the visual quality of the product in terms of overall acceptability for four days at 20 °C and 20 days at 7 °C.
- ItemMachine Learning for Determining Interactions between Air Pollutants and Environmental Parameters in Three Cities of Iran(Basel : MDPI, 2022) Rad, Abdullah Kaviani; Shamshiri, Redmond R.; Naghipour, Armin; Razmi, Seraj-Odeen; Shariati, Mohsen; Golkar, Foroogh; Balasundram, Siva K.Air pollution, as one of the most significant environmental challenges, has adversely affected the global economy, human health, and ecosystems. Consequently, comprehensive research is being conducted to provide solutions to air quality management. Recently, it has been demonstrated that environmental parameters, including temperature, relative humidity, wind speed, air pressure, and vegetation, interact with air pollutants, such as particulate matter (PM), NO2, SO2, O3, and CO, contributing to frameworks for forecasting air quality. The objective of the present study is to explore these interactions in three Iranian metropolises of Tehran, Tabriz, and Shiraz from 2015 to 2019 and develop a machine learning-based model to predict daily air pollution. Three distinct assessment criteria were used to assess the proposed XGBoost model, including R squared (R2), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE). Preliminary results showed that although air pollutants were significantly associated with meteorological factors and vegetation, the formulated model had low accuracy in predicting (R2PM2.5 = 0.36, R2PM10 = 0.27, R2NO2 = 0.46, R2SO2 = 0.41, R2O3 = 0.52, and R2CO = 0.38). Accordingly, future studies should consider more variables, including emission data from manufactories and traffic, as well as sunlight and wind direction. It is also suggested that strategies be applied to minimize the lack of observational data by considering second-and third-order interactions between parameters, increasing the number of simultaneous air pollution and meteorological monitoring stations, as well as hybrid machine learning models based on proximal and satellite data.
- ItemSupportive Business Environments to Develop Grass Bioeconomy in Europe(Basel : MDPI, 2021) Orozco, Richard; Mosquera-Losada, María Rosa; Rodriguez, Javier; Adamseged, Muluken Elias; Grundmann, PhilippGrasslands cover almost half of the total European agricultural area and are the source of a wide range of public goods and services. Yet, their potential to produce innovative bio-based products, such as paper and plastic, remains widely untapped. We employ a multiple case study approach and implement the Business Environment Framework by Adamseged and Grundmann (2020) on eighteen alternative grass-based businesses to investigate the interdependencies between these successful business models and their business environments. The subsequent analysis reveals that the deployment of funds and policies to support alternative grass-based products remains low in most regions of Europe. Our findings highlight that aligned funding mechanisms that incorporate and promote the specific benefits generated by grass-producing and grass-processing businesses are key to overcoming the barriers related to the competition of bio-based products with the established fossil-fuels-based economic system. To make alternative grass-based markets more dynamic, increasing consumer awareness through adequate marketing is perceived as an important aspect. Capacity building and alignment efforts need to be strengthened and coordinated at local and higher levels to enable the replication and scale-up of novel grass-based businesses in Europe and beyond.
- ItemDevelopment of Biorefineries in the Bioeconomy: A Fuzzy-Set Qualitative Comparative Analysis among European Countries(Basel : MDPI, 2021) Ding, Zhengqiu; Grundmann, PhilippThis study aims to identify the configurational conditions that characterize the establish-ment of biorefineries in 20 European countries. After determining the conditions which support a bioeconomy transition, secondary data from national sources are used to represent their existing conditions within respective countries. Then, a fuzzy-set qualitative comparative analysis is em-ployed to compare and contrast the effect of varying combinations of the selected conditions on the development of biorefineries. The conditions chosen include coherent bioeconomy strategies, network intensity of regional bioclusters, intellectual capital, and natural resource availability. Our results reveal that the configuration of a coherent bioeconomy strategy, sizable public spending on R&D, abundant biomass supply, and a high level of network intensity is sufficient to explain the pro-nounced biorefineries development among some European countries. We recommend that countries with fragmented approaches review and redesign the policy and regulatory framework to create a holistic and consistent bioeconomy strategy, taking into account the configurations of conditions as an important prerequisite. In particular, factors such as the lack of best practice examples, the low level of public spending on research and development, the economic capacities for a skilled workforce in addition to the sustainable supply of raw materials should be addressed as focal points.
- ItemInvestigating Solid and Liquid Desiccant Dehumidification Options for Room Air-Conditioning and Drying Applications(Basel : MDPI, 2020) Naik, B. Kiran; Joshi, Mullapudi; Muthukumar, Palanisamy; Sultan, Muhammad; Miyazaki, Takahiko; Shamshiri, Redmond R.; Ashraf, HadeedThis study reports on the investigation of the performance of single and two-stage liquid and solid desiccant dehumidification systems and two-stage combined liquid and solid desiccant dehumidification systems with reference to humid climates. The research focus is on a dehumidification system capacity of 25 kW designed for room air conditioning application using the thermal models reported in the literature. RD-type silica gel and LiCl are used as solid and liquid desiccant materials, respectively. In this study, the application of proposed system for deep drying application is also explored. Condensation rate and moisture removal efficiency are chosen as performance parameters for room air conditioning application, whereas air outlet temperature is chosen as performance parameter for deep drying application. Further, for a given range of operating parameters, influences of air inlet humidity ratio, flow rate, and inlet temperature on performance parameters of the systems are investigated. In humid climatic conditions, it has been observed that a two-stage liquid desiccant dehumidification system is more effective for room air conditioning application, and two-stage solid desiccant dehumidification system is more suitable for deep drying application in the temperature range of 50 to 70 °C, while single-stage solid desiccant and two-stage combined liquid and solid desiccant dehumidification systems are more effective for low temperature, i.e., 30 to 50 °C deep drying application.
- ItemAnthropogenic Land Use Change and Adoption of Climate Smart Agriculture in Sub-Saharan Africa(Basel : MDPI, 2022) Tione, Sarah Ephrida; Nampanzira, Dorothy; Nalule, Gloria; Kashongwe, Olivier; Katengeza, Samson PilanazoCompelling evidence in Sub-Saharan Africa (SSA) shows that Climate-Smart Agriculture (CSA) has a positive impact on agricultural productivity. However, the uptake of CSA remains low, which is related to anthropogenic, or human-related, decisions about CSA and agricultural land use. This paper assesses households’ decisions to allocate agricultural land to CSA technologies across space and over time. We use the state-contingent theory, mixed methods, and mixed data sources. While agricultural land is increasing, forest land is decreasing across countries in SSA. The results show that household decisions to use CSA and the extent of agricultural land allocation to CSA remain low with a negative trend over time in SSA. Owned land and accessing land through rental markets are positively associated with allocating land to CSA technologies, particularly where land pressure is high. Regarding adaptation, experiencing rainfall shocks is significantly associated with anthropogenic land allocation to CSA technologies. The country policy assessment further supports the need to scale up CSA practices for adaptation, food security, and mitigation. Therefore, scaling up CSA in SSA will require that agriculture-related policies promote land tenure security and land markets while promoting climate-smart farming for food security, adaptation, and mitigation.
- ItemEvaluating Three-Pillar Sustainability Modelling Approaches for Dairy Cattle Production Systems(Basel : MDPI, 2021) Díaz de Otálora, Xabier; del Prado, Agustín; Dragoni, Federico; Estellés, Fernando; Amon, BarbaraMilk production in Europe is facing major challenges to ensure its economic, environmental, and social sustainability. It is essential that holistic concepts are developed to ensure the future sustainability of the sector and to assist farmers and stakeholders in making knowledge-based decisions. In this study, integrated sustainability assessment by means of whole-farm modelling is presented as a valuable approach for identifying factors and mechanisms that could be used to improve the three pillars (3Ps) of sustainability in the context of an increasing awareness of economic profitability, social well-being, and environmental impacts of dairy production systems (DPS). This work aims (i) to create an evaluation framework that enables quantitative analysis of the level of integration of 3P sustainability indicators in whole-farm models and (ii) to test this method. Therefore, an evaluation framework consisting of 35 indicators distributed across the 3Ps of sustainability was used to evaluate three whole-farm models. Overall, the models integrated at least 40% of the proposed indicators. Different results were obtained for each sustainability pillar by each evaluated model. Higher scores were obtained for the environmental pillar, followed by the economic and the social pillars. In conclusion, this evaluation framework was found to be an effective tool that allows potential users to choose among whole-farm models depending on their needs. Pathways for further model development that may be used to integrate the 3P sustainability assessment of DPS in a more complete and detailed way were identified.
- ItemEvaluating Evaporative Cooling Assisted Solid Desiccant Dehumidification System for Agricultural Storage Application(Basel : MDPI, 2022) Hussain, Ghulam; Aleem, Muhammad; Sultan, Muhammad; Sajjad, Uzair; Ibrahim, Sobhy M.; Shamshiri, Redmond R.; Farooq, Muhammad; Usman Khan, Muhammad; Bilal, MuhammadThe study aims to investigate Maisotsenko cycle evaporative cooling assisted solid desiccant air‐conditioning (M‐DAC) system for agricultural storage application. Conventional air‐conditioning (AC) systems used for this application are refrigeration‐based which are expensive as they consume excessive amount of primary‐energy. In this regard, the study developed a lab‐scale solid silica gel‐based desiccant AC (DAC) system. Thermodynamic performance of the developed system was investigated using various adsorption/dehumidification and desorption/regeneration cycles. The system possesses maximum adsorption potential i.e., 4.88 g/kg‐DA at higher regeneration temperature of 72.6 °C and long cycle time i.e., 60 min: 60 min. Moreover, the system’s energy consumption performance was investigated from viewpoints of maximum latent, sensible, and total heat as well as latent heat ratio (LHR), which were found to be 0.64 kW, 1.16 kW, and 1.80 kW, respectively with maximum LHR of 0.49. Additionally, the study compared standalone DAC (S‐ DAC), and M‐DAC system thermodynamically to investigate the feasibility of these systems from the viewpoints of temperature and relative humidity ranges, cooling potential (Qp), and coefficient of performance (COP). The S‐DAC system showed temperature and relative humidity ranging from 39 °C to 48 °C, and 35% to 66%, respectively, with Qp and COP of 17.55 kJ/kg, and 0.37, respectively. Conversely, the M‐DAC system showed temperature and relative humidity ranging from 17 °C to 25 °C, and 76% to 98%, respectively, with Qp and COP of 41.80 kJ/kg, and 0.87, respectively. Additionally, the study investigated respiratory heat generation rate (Qres), and heat transfer rate (Qrate) by agricultural products at different temperature gradient (∆T) and air velocity. The Qres and Qrate by the products were increased with ∆T and air velocity, respectively, thereby generating heat loads in the storage house. Therefore, the study suggests that the M‐DAC system could be a potential AC option for agricultural storage application.