• Energy Research

Giant reed (Arundo Donax L.) is a perennial, non-food and low-input energy crop representing a promising solution to produce renewable energy at low cost, especially in marginal areas - i.e. low profitable areas which are prone to land abandonment. This research investigates the effect of two levels of irrigation (100% ETm and rainfed) on a 20-year old plantation of 40 genotypes of giant reed (Arundo donax L.) collected around Southern Italy. The experimental methanogenic potential of the biomass was defined trough the BMP test (Biochemical Methane Potential). The trial shows that several genotypes maintain high biomass yield and thus high biomethane potential yield even from old plantations. The variability of biomass yield and biomethane potential yield among genotypes is high. Giant reed genotypes show a positive response to the irrigation, which represent the main limiting factor in Mediterranean environments. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 234-237

Giant reed (Arundo Donax L.) is a perennial, non-food and low-input energy crop representing a promising solution to produce renewable energy at low cost, especially in marginal areas - i.e. low profitable areas which are prone to land abandonment. This research investigates the effect of two levels of irrigation (100% ETm and rainfed) on a 20-year old plantation of 40 genotypes of giant reed (Arundo donax L.) collected around Southern Italy. The experimental methanogenic potential of the biomass was defined trough the BMP test (Biochemical Methane Potential). The trial shows that several genotypes maintain high biomass yield and thus high biomethane potential yield even from old plantations. The variability of biomass yield and biomethane potential yield among genotypes is high. Giant reed genotypes show a positive response to the irrigation, which represent the main limiting factor in Mediterranean environments. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 234-237

Salinity is one of the most important challenge facing the supply of food to the world population in the future. The soil electrical conductivity threshold set by the Joint Research Center (JRC) to define marginal lands due to salinity is 3.2 dS/m in the top soil. The aim of the present study was to evaluate the biomass yield, morphology and physiology of three different perennial energy grasses, namely Arundo donax, Miscanthus x giganteus and Saccharum spontaneum ssp. aegypticum under increasing soil salinity levels (0, 9.0 and 18.0 dS/m) and NPK fertilization differentiation (0, 60 and 120 kg ha-1). The leaf area index (LAI) of investigated species under salinity and fertilization treatments showed an upward trend followed by a decline as the growing seasons progressed. Across treatments, Arundo showed the highest LAI. In Miscanthus this trait was much more affected by salinity levels than Sacchaum. LAI reduced proportionally with increasing salinity and decreasing fertilization levels. The instantaneous water use efficiency (iWUE), which represents the net photosynthesis over the transpiration rate, showed a fluctuating trend around the mean throughout the growing season. It was the highest in the C4 crops, however, across the average of treatments, the C3 Arundo had an iWUE as high as the other crops in comparison. Surprisingly, the higher the salinity levels the higher the iWUE, across species and fertilization. Fertilization, across species and salinity levels, led to a higher iWUE in unfertilized and intermediated than the highest fertilization level. As expected, the biomass weight at harvest showed a significant effect of species, salinity and fertilization. Across the average of salinity and fertilization, Arundo and Saccharum showed the highest yields (21.8 and 19.4 g plant-1), and Miscanthus the lowest (7.2 g plant-1). Across the average of species and fertilization, there was a significantly higher yield on the lowest salinity level (24.9 g plant-1), followed by the intermediate (13.3 g plant-1) and the highest salinity condition (10.1 g plant-1). The highest level of fertilization significantly improved the biomass weight as compared with the control and the medium fertilization level. Increasing the knowledge on energy crops under soils affected by salinity is strategic to reduce land abandonment, recommending bioenergy crops for marginal lands where food crops may face difficulties to be grown, in turn decreasing the food vs fuel competition and the effect of land use changes. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 216-221

Salinity is one of the most important challenge facing the supply of food to the world population in the future. The soil electrical conductivity threshold set by the Joint Research Center (JRC) to define marginal lands due to salinity is 3.2 dS/m in the top soil. The aim of the present study was to evaluate the biomass yield, morphology and physiology of three different perennial energy grasses, namely Arundo donax, Miscanthus x giganteus and Saccharum spontaneum ssp. aegypticum under increasing soil salinity levels (0, 9.0 and 18.0 dS/m) and NPK fertilization differentiation (0, 60 and 120 kg ha-1). The leaf area index (LAI) of investigated species under salinity and fertilization treatments showed an upward trend followed by a decline as the growing seasons progressed. Across treatments, Arundo showed the highest LAI. In Miscanthus this trait was much more affected by salinity levels than Sacchaum. LAI reduced proportionally with increasing salinity and decreasing fertilization levels. The instantaneous water use efficiency (iWUE), which represents the net photosynthesis over the transpiration rate, showed a fluctuating trend around the mean throughout the growing season. It was the highest in the C4 crops, however, across the average of treatments, the C3 Arundo had an iWUE as high as the other crops in comparison. Surprisingly, the higher the salinity levels the higher the iWUE, across species and fertilization. Fertilization, across species and salinity levels, led to a higher iWUE in unfertilized and intermediated than the highest fertilization level. As expected, the biomass weight at harvest showed a significant effect of species, salinity and fertilization. Across the average of salinity and fertilization, Arundo and Saccharum showed the highest yields (21.8 and 19.4 g plant-1), and Miscanthus the lowest (7.2 g plant-1). Across the average of species and fertilization, there was a significantly higher yield on the lowest salinity level (24.9 g plant-1), followed by the intermediate (13.3 g plant-1) and the highest salinity condition (10.1 g plant-1). The highest level of fertilization significantly improved the biomass weight as compared with the control and the medium fertilization level. Increasing the knowledge on energy crops under soils affected by salinity is strategic to reduce land abandonment, recommending bioenergy crops for marginal lands where food crops may face difficulties to be grown, in turn decreasing the food vs fuel competition and the effect of land use changes. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 216-221

Increasing energy demand and fossil fuel prices together with environmental concerns have motivated scientists to find alternative energy sources such as biofuels. Biofuels are renewable and biodegradable sources of energy with beneficial environmental impacts. Biodiesel is a mixture of mono alkyl esters of vegetable oils or animal fats. Currently, more than 95% of the world biodiesel is produced from edible vegetable oils through different transesterification systems. Castor oil is an excellent raw material in terms of price and quality, but especially this non-edible vegetable oil does not have any issues or compromise food security. Recently, the use of castor oil has attracted attention for producing and optimizing biodiesel production, due to its high content and the possibility to esterify with only methanol, which assures low production costs. Additionally, the use of feedstocks as vegetable oils can contribute to decreasing greenhouses gases such as carbon dioxide, because these oils are obtained from crops which have previously captured this gas during their photosynthetic process. The innovative aspect of this study is the evaluation of the morphologic and productive response of castor bean to changing soil water and nitrogen fertilization under the semiarid Mediterranean climate. Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 85-88

Increasing energy demand and fossil fuel prices together with environmental concerns have motivated scientists to find alternative energy sources such as biofuels. Biofuels are renewable and biodegradable sources of energy with beneficial environmental impacts. Biodiesel is a mixture of mono alkyl esters of vegetable oils or animal fats. Currently, more than 95% of the world biodiesel is produced from edible vegetable oils through different transesterification systems. Castor oil is an excellent raw material in terms of price and quality, but especially this non-edible vegetable oil does not have any issues or compromise food security. Recently, the use of castor oil has attracted attention for producing and optimizing biodiesel production, due to its high content and the possibility to esterify with only methanol, which assures low production costs. Additionally, the use of feedstocks as vegetable oils can contribute to decreasing greenhouses gases such as carbon dioxide, because these oils are obtained from crops which have previously captured this gas during their photosynthetic process. The innovative aspect of this study is the evaluation of the morphologic and productive response of castor bean to changing soil water and nitrogen fertilization under the semiarid Mediterranean climate. Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 85-88

Reducing agronomic input supply can significantly contribute to decrease the environmental impact of bioenergy cropping systems. Currently, there is a renewed industrial interest in non-food oil crops for different end-uses application. Among species from Brassica genus, Brassica carinata A. Braun is an interesting winter annual crop in warm and semi-arid environments and may provide a rotation alternative with cereal crops, sourcing non-edible oil for the industry, additional incomes to the farmers and soil benefits. The present study compared four Brassica carinata lines (GID-6165, GIP-6164, GID-6091, GID-6084) under two different organic fertilization levels (80 and 160 kg N ha-1) in a semiarid Mediterranean area. These four lines have not been tested in Southern Italy previously, nor under the present low-input cultivation practices in semiarid Mediterranean area. Main findings showed a significant fertilization effect (P=0.05), with the high-input providing higher seed yields and harvest index than low-input. There was no genotype effect, however, the gap between potential (i.e. seed yield at the programmed plant density) and actual yields was rather high for GID-6165 and GID-6080. On the other hand, genotype had the largest effect on the thousand seed weight and the residual biomass yield. In general, GID-6091 and GID-6165 reached seed physiological maturity earlier than GID-6084 and GID-6164 lines. The present study proved that improved B. carinata lines can be grown in semiarid Mediterranean area under low-input organic systems, providing satisfactory seed yields. However, seedbed preparation was noticed to be key to narrow the gap between potential and actual seed yield, particularly under the present clay soil. Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 120-124

Reducing agronomic input supply can significantly contribute to decrease the environmental impact of bioenergy cropping systems. Currently, there is a renewed industrial interest in non-food oil crops for different end-uses application. Among species from Brassica genus, Brassica carinata A. Braun is an interesting winter annual crop in warm and semi-arid environments and may provide a rotation alternative with cereal crops, sourcing non-edible oil for the industry, additional incomes to the farmers and soil benefits. The present study compared four Brassica carinata lines (GID-6165, GIP-6164, GID-6091, GID-6084) under two different organic fertilization levels (80 and 160 kg N ha-1) in a semiarid Mediterranean area. These four lines have not been tested in Southern Italy previously, nor under the present low-input cultivation practices in semiarid Mediterranean area. Main findings showed a significant fertilization effect (P=0.05), with the high-input providing higher seed yields and harvest index than low-input. There was no genotype effect, however, the gap between potential (i.e. seed yield at the programmed plant density) and actual yields was rather high for GID-6165 and GID-6080. On the other hand, genotype had the largest effect on the thousand seed weight and the residual biomass yield. In general, GID-6091 and GID-6165 reached seed physiological maturity earlier than GID-6084 and GID-6164 lines. The present study proved that improved B. carinata lines can be grown in semiarid Mediterranean area under low-input organic systems, providing satisfactory seed yields. However, seedbed preparation was noticed to be key to narrow the gap between potential and actual seed yield, particularly under the present clay soil. Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 120-124