Biochar Improves the Properties of Poultry Manure Compost as Growing Media for Rosemary Production

[EN] Compost represents a sustainable alternative for peat (P) replacement in soilless plant cultivation, but its use can be limited by several inadequate physical and physicochemical properties. Biochar can alleviate some of the limitations of compost for its use as growth media by improving the physical properties, decreasing salinity and making the phytotoxic compounds unavailable for plants. We studied the physical and physicochemical properties of holm oak biochar (B), poultry manure compost (PMC), poultry manure composted with biochar (PMBC), a commercial peat (P) and multiple combinations of these materials as growth media, and their effect on the rooting and growth of rosemary. PMBC and PMC showed similar physical and physicochemical properties as growing media, and they both were phytotoxic when used in a rate above 50% (by volume) in the growing medium. However, when used at proportion of 25%, PMBC was less phytotoxic than PMC and enhanced the percentage of rosemary cutting rooting. The incorporation of B in the growing medium instead of P (either at 50% or 75% in volume) increased the stability of the growing media and the percentage of rooted cuttings, but it did not affect plant growth significantly. Our results demonstrate the potential of substituting peat by a combination of poultry manure compost and biochar for the formulation of growth media.This research was funded by SPANISH MINISTRY OF ECONOMY AND COMPETITIVENESS, grant numbers AGL2012-40143-C02-01 and RTI2018-099417-B-I00, co-funded with EU FEDER fundsFornes Sebastiá, F.; Liu-Xu, L.; Lidón, A.; Sanchez-Garcia, M.; Luz Cayuela, M.; Sanchez-Monedero, MA.; Belda Navarro, RM. (2020). Biochar Improves the Properties of Poultry Manure Compost as Growing Media for Rosemary Production. 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Bioresource Technology, 192, 272-279. doi:10.1016/j.biortech.2015.05.003Maroušek, J., Hašková, S., Zeman, R., Žák, J., Vaníčková, R., Maroušková, A., … Myšková, K. (2015). Polemics on Ethical Aspects in the Compost Business. Science and Engineering Ethics, 22(2), 581-590. doi:10.1007/s11948-015-9664-yAbad, M., Fornes, F., Carrión, C., Noguera, V., Noguera, P., Maquieira, A., & Puchades, R. (2005). Physical Properties of Various Coconut Coir Dusts Compared to Peat. HortScience, 40(7), 2138-2144. doi:10.21273/hortsci.40.7.2138Laird, D., Fleming, P., Wang, B., Horton, R., & Karlen, D. (2010). Biochar impact on nutrient leaching from a Midwestern agricultural soil. Geoderma, 158(3-4), 436-442. doi:10.1016/j.geoderma.2010.05.012Jaiswal, A. K., Elad, Y., Paudel, I., Graber, E. R., Cytryn, E., & Frenkel, O. (2017). Linking the Belowground Microbial Composition, Diversity and Activity to Soilborne Disease Suppression and Growth Promotion of Tomato Amended with Biochar. 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Soil C Storage Potential of Exogenous Organic Matter at Regional Level (Italy) Under Climate Change Simulated by RothC Model Modified for Amended Soils

Soil amendment with exogenous organic matter (EOM) represents an effective option for sustainable management of organic residues and enhancement of soil organic C (SOC) content. Optimization of soil amendment is hampered by the high variability in EOM quality and pedoclimatic conditions. A possible solution to this problem could be represented by spatially explicit soil C modeling. The aim of this study was the evaluation at regional level of the long term C storage potential of EOM added to the soil under climate change by using a modified version of the RothC specifically developed for C simulation in amended soil. To achieve this goal a spatially explicit version of the modified RothC model was deployed to assess at a national scale the potential for C storage of agricultural soils amended with different EOMs. Long term model simulations of continuous amendment (100 years) indicated that EOMs greatly differ for their soil C sequestration potential (range 0.110–0.385 t C ha−1 y−1), mainly depending to their degree of stabilization. Spatial explicit modeling of amended soil, taking into account the different combinations of EOMs and application sites, indicated a high variability in the potential of SOC accumulation at the national level (range: 0.06–0.62 t C ha−1 y−1). EOM quality showed a larger impact on long term SOC accumulation than variability in pedoclimatic conditions. Model simulations predicted that the contribution of soil amendment in tackling greenhouse gas (GHG) emissions is limited: soil C sequestration potential of compost applied to all Italian agricultural land corresponded to 5.3% of the total annual GHG emissions in Italy. Large scale modeling enables areas with the largest potential for EOM accumulation to be identified, therefore suggesting ways for optimizing resources. The spatially explicit version of the modified RothC model improves the predictive power of SOC modeling at regional scale in amended soils, because it takes into account, besides variability in pedoclimatic conditions, the large differences in EOMs quality

Biochar as a tool to reduce the agricultural greenhouse-gas burden–knowns, unknowns and future research needs

Agriculture and land use change has significantly increased atmospheric emissions of the non-CO2 green-house gases (GHG) nitrous oxide (N2O) and methane (CH4). Since human nutritional and bioenergy needs continue to increase, at a shrinking global land area for production, novel land management strategies are required that reduce the GHG footprint per unit of yield. Here we review the potential of biochar to reduce N2O and CH4 emissions from agricultural practices including potential mechanisms behind observed effects. Furthermore, we investigate alternative uses of biochar in agricultural land management that may significantly reduce the GHG-emissions-per-unit-of-product footprint, such as (i) pyrolysis of manures as hygienic alternative to direct soil application, (ii) using biochar as fertilizer carrier matrix for underfoot fertilization, biochar use (iii) as composting additive or (iv) as feed additive in animal husbandry or for manure treatment. We conclude that the largest future research needs lay in conducting life-cycle GHG assessments when using biochar as an on-farm management tool for nutrient-rich biomass waste streams. © 2017 The Author(s) Published by VGTU Press and Informa UK Limited, [trading as Taylor & Francis Group]

CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

¿Qué tipos de biochar favorecen la reducción del N2O a N2 en suelos agrícolas?

De entre las fuentes antropogénicas, los suelos agrícolas son los mayores emisores de óxido nitroso (N2O) a la atmósfera. Se ha demostrado que el biochar, un producto con alto contenido en carbono que se obtiene mediante la pirólisis de residuos orgánicos, reduce la emisión de GEIs, y en especial de N2O, cuando es añadido al suelo. El mecanismo por el cual el biochar tiene este efecto permanece sin determinar, aunque son numerosas las propuestas tanto las de carácter abiótico como biótico. Entre las más apoyadas, se encuentran: la capacidad del biochar para alterar la actividad microbiana de los organismos que intervienen en el ciclo del N del suelo; las modificaciones que el biochar provoca sobre diversas funciones y propiedades del suelo al reaccionar con las formas de nitrógeno que en el coexisten (nitrato, nitrito o N2O); o su acción como intermediario en las reacciones redox del suelo, como donador o aceptor de electrones. Recientes estudios apuntan este último mecanismo como una de las que tendría mayor relevancia donde, en concreto, el biochar intervendría de manera activa en el último paso de la desnitrificación, en el que el N2O es reducido a nitrógeno (N2). Sin embargo, aunque algunos estudios han demostrado esta teoría, no se han determinado aún cuales son las características del biochar que ejercen una mayor influencia y que, por tanto, serían más efectivos. Una de las mayores dificultades que se plantean es la variabilidad en cuanto a las propiedades físicas y químicas que tienen los biochars. Sin embargo, el conjunto de sus características (i.e. H:Corg, porosidad, composición lignocelulósica) resultan claves para la acción final que el biochar genere, pues determinarán su capacidad para intercambiar electrones con los microorganismos reductores de N2O y favorecer así su acción. Con el objetivo de estudiar cómo el proceso de reducción N2O en el suelo se ve alterado por la presencia de diferentes bichars previamente caracterizados, se han se están realizando ensayos de incubación bajo condiciones controladas. En recipientes cerrados, a mezclas con diferentes grados de humedad de suelo y biochar (2%) se aplica una cantidad conocida de N2O cuya evolución se monitoriza con el tiempo. Inicialmente, el biochar ensayado se ha sintetizado a 400 °C partir de residuos de poda de olivo, al cual seguirán otros producidos a partir de diferentes materiales de partida. De esta manera, se será capaz de vincular las propiedades de cada biochar con su capacidad para favorecer la transformación de N2O en N2. Se presentarán los resultados de la evolución de la concentración de N2O en el ensayo de incubación descrito y las propiedades de los biochar ensayados; todo ello junto con un análisis que relacione ambos parámetros.Peer reviewe

USE OF ORGANIC RESIDUES FOR THE RECOVERY OF SOIL AND ENVIRONMENTAL SUSTAINABILITY

The aim of this work was to investigate the effects of different organic residues on soil fertility and climate change, through the evaluation of soil organic matter mineralisation, greenhouse gas emission, nutrient availability and soil microbial biomass content and activity. A degraded agricultural soil was amended with three different organic residues (pig slurry digestate, rapeseed meal, and compost) at three different doses (0.1, 0.25 and 0.5% w/w) and incubated for 30 days at 20 ºC. During incubation, soil CO2 and N2O emissions, K2SO4 extractable organic C, N, NH4+, NO3- and P, soil microbial biomass and some enzymatic activities were determined. Results obtained showed that rapeseed meal and pig slurry are best suited to improve soil chemical and biological fertility, while compost is more appropriate for the enhancement of soil organic matter content and to promote soil C sequestration

UTILIZZO DI RESIDUI DA PROCESSI BIOENERGETICI COME AMMENDANTI: IMPLICAZIONI SULLA FERTILITÀ DEL SUOLO ED IL SEQUESTRO DEL CARBONIO

The increasing use of renewable energy sources as substitutes to fossil fuels has provoked an increase in the production of bioenergy residues. These residues could be effectively used for the recovery and conservation of soil fertility. However, the effect of the organic residues on the soil ecosystem is different depending on their physico-chemical characteristics and, particularly, the knowledge of the impact of bioenergy residues on soil quality is still limited. The aim of this work is to study the effects of different bioenergy residues on C and N mineralization and soil microbial content and activity. A degraded soil (clay 49.7%, pH 7, OC 0.37%) from Southern Spain was amended (0.5% w/w) with four different bioenergy residues (anaerobic digestate, rapeseed meal from biodiesel production, bioethanol residue and biochar) and three other organic residues commonly used as organic amendments (wastewater sludge and two composts). The amended soil was then incubated for 30 days at 20 ºC. During incubation soil CO2 evolution was measured every 4 hours by means of an automatic chromatographic system. After 2, 7 and 30 days of incubation the following parameters were also analysed: K2SO4-extractable C, N, NO3 -, NH4 + and P, microbial biomass C and some enzymatic activities involved in the cycle of the main nutritive elements (β-glucosidase, arylsulfatase, esterase, alkaline and acid phosphatase and leucine aminopeptidase). Soil addition of the different residues led to a general increase in C and N mineralization, in the availability of nutrients and in the microbial content and activity, but with remarkable different values and dynamics. The only exception was represented by biochar that did not cause any significant variations of the measured parameters with respect to the control. The obtained results demonstrate that bioenergy residues may represent an effective alternative to usual amendments for the recovery and conservation of soil quality. The different physico-chemical characteristics of the residues suggest different uses. Rapeseed meal, bioethanol residue and anaerobic digestate are more suited to improve soil biological fertility, while biochar is more appropriated for the enhancement of soil organic matter content and to promote soil C sequestration.L’augmentation de l’utilisation d’énergies renouvelables comme substituts des combustibles fossiles a provoqué une nette augmentation de la production de résidus bioénergétiques. De tels déchets peuvent être utilisés pour le rétablissement et la conservation de la fertilité des sols. Pourtant, l’effet des résidus organiques sur l’écosystème du sol est différent selon ses caractéristiques physico-chimiques. En particulier, les connaissances concernant l’impact des résidus bioénergétiques sur la qualité du sol sont encore limitées. Nous avons étudié les effets de résidus de différents processus bioénergétiques sur la minéralisation de C et N ainsi que sur le contenu et l’activité des microorganismes. Un sol dégradé (argile 49.7 %, pH 7, CO 0.37 %) provenant de l’Espagne méridionale a été amendé (0.5 % m/m) avec quatre différents résidus bioénergétiques (déchets de la digestion anaérobique, farine de colza de la production de biodiesel, résidus de la production de bioéthanol et de charbon de bois) et trois résidus organiques habituellement utilisés comme amendements (boue de dépurateur et deux types de compost). Le sol, après amendement, a été incubé 30 jours à 20 ºC. Au cours de l’incubation, l’évolution de CO2 a été mesurée à intervalles de quatre heures par chromatographie. Après 2, 7 et 30 jours les paramètres suivant ont été analysés: C, N, NO3 -, NH4 + et P extractible par K2SO4, C de la biomasse microbienne et certaines activités enzymatiques impliquées dans le cycle des principaux éléments nutritifs (β-glucosidase, arylsulfatase, estérase, phosphatase alcaline et acide ainsi que leucylaminopeptidase). L’addition de divers résidus au sol a provoqué en générale une augmentation de la minéralisation de C et N, de la disponibilité des nutriments et du contenu et activité des microorganismes ; tout ceci avec de significatives différences aussi bien en terme de quantité que de dynamique. L’addition de résidus de la production de charbon de bois n’a pas provoqué de variation significative des paramètres mesurés par rapport au témoin. Les résultats obtenus démontrent que les résidus bioénergétiques peuvent représenter une alternative efficace aux amendements habituels pour le rétablissement et la conservation de la qualité du sol. Les différentes caractéristiques physico-chimiques des résidus suggèrent diverses modalités d’utilisation. La farine de colza, le résidu de la production de bioéthanol et les produits de la digestion anaérobique sont plus indiqués pour améliorer la fertilité biologique du sol alors que le charbon de bois est plus approprié pour augmenter le contenu en matière organique et favoriser la capture de C.L’aumento dell’utilizzo di energie rinnovabili come sostituti dei combustibili fossili ha provocato un consistente incremento nella produzione di residui bioenergetici. Tali residui possono essere convenientemente utilizzati per il recupero ed il mantenimento della fertilità dei suoli. Tuttavia, l’effetto dei residui organici sull’ecosistema del suolo è diverso a seconda delle sue caratteristiche fisico-chimiche. In particolare le conoscenze sull’impatto dei residui dei processi bioenergetici sulla qualità del suolo sono ancora limitate. Lo scopo di questo lavoro era pertanto lo studio degli effetti di residui da diversi processi bioenergetici sulla mineralizzazione di C e N ed il contenuto ed attività dei microorganismi del suolo. Un suolo degradato (argilla 49.7%, pH 7, CO 0.37%) proveniente dalla Spagna meridionale è stato ammendato (0.5% p/p) con quattro diversi residui da processi bionergetici (residuo della digestione anaerobica, farina di colza dalla produzione di biodiesel, residuo della produzione di bioetanolo e biocarbone) e tre residui organici comunemente usati come ammendanti (fango di depurazione e due tipi di compost). Il suolo ammendato è stato poi incubato per 30 giorni a 20 ºC. Durante l’incubazione è stata misurata l’evoluzione della CO2 ogni 4 ore mediante un sistema cromatografico automatizzato. Dopo 2, 7 e 30 giorni di incubazione sono stati analizzati i seguenti parametri: C, N, NO3 -, NH4 + e P estraibili con K2SO4, C della biomassa microbica e alcune attività enzimatiche implicate nel ciclo dei principali elementi nutritivi (β-glucosidasi, arilsulfatasi, esterasi, fosfatasi acida e alcalina e leucina aminopeptidasi). L’aggiunta dei diversi residui al suolo ha provocato in generale un aumento nella mineralizzazione di C e N, nella disponibilità di nutrienti e nel contenuto ed attività dei microorganismi, ma con significative differenze nella quantità e dinamica. L’unica eccezione è stata costituita dal biocarbone che non ha causato variazioni significative dei parametri misurati rispetto al ontrollo. I risultati ottenuti dimostrano che i residui bionergetici possono rappresentare un’alternativa efficace ai comuni ammendanti per il recupero ed il mantenimento della qualità del suolo. Tuttavia le diverse caratteristiche chimico-fisiche dei residui suggeriscono differenti modalità di utilizzo. La farina di colza, il residuo della produzione di bioetanolo ed il digestato sono più indicati per migliorare la fertilità biologica del suolo, mentre il biocarbone è più appropriato per aumentare il contenuto di materia organica del suolo e favorire il sequestro del C

Efecto del biochar en la producción y oxidación de CH4 en suelos agrícolas

El CH4 es el segundo gas de efecto invernadero (GEIs) más importante, cuyo potencial de calentamiento es 34 veces superior al del CO2. La contribución de la agricultura a la emisión de GEIs de procedencia antropogénica alcanza el 12%, siendo el CH4 el responsable de la mitad de estas emisiones; valor que está en aumento debido al crecimiento de la población mundial. El biochar es el producto resultante de someter residuos de origen orgánico a un proceso de pirolisis a altas temperaturas en ausencia de oxígeno. Un alto porcentaje del C biodegradable de la biomasa original se convierte en una forma más estable y recalcitrante, lo que favorece el secuestro de C en el suelo (disminuye la liberación de CO2). Además, numerosos estudios han demostrado la reducción que produce en la emisión de otros GEIs, como son el CH4 y el N2O. Estos efectos se producirían debido a la influencia que el biochar tiene, entre otros, en los ciclos biogeoquímicos del C y N en el suelo, su comunidad microbiana, pH o aireación. Numerosas investigaciones han estudiado el efecto de la aplicación de biochar en las emisiones de CH4 de suelos agrícolas. Se han obtenido resultados dispares que son una muestra de la cantidad de variables que intervienen, tales como, el material de partida, la temperatura del proceso de pirólisis, el porcentaje de biochar que se añade, las características del suelo objeto de estudio, el clima, las condiciones del experimento, etc. Se une como variable la compleja actividad del CH4 en el suelo, que puede ser producido u oxidado (organismos metanogénicos o metanótrofos) dependiendo de las condiciones ambientales (anóxicas u óxicas). Sin embargo, se ha demostrado que el biochar es capaz de reducir de manera significativa las emisiones de CH4. Por un lado, hay evidencias del potencial del biochar en suelos encharcados de arrozal, en especial los de pH ácido, en los cuales se incrementaría la actividad de los organismos metanótrofos. Por otro lado, los biochars generados en procesos de pirólisis a altas temperaturas (>600 ⁰C) incrementan el efecto sumidero de CH4 del suelo en comparación con los que se producen a temperaturas menores de 600 ⁰C. Esto se debe a que contienen una menor cantidad de compuestos lábiles en su estructura que son, entre otros, sustrato para las comunidades microbiológicas. Por último, la cantidad de biochar aplicada también debe ser tenida en cuenta: si es añadido en altas concentraciones, retiene iones amonio que entran en competición con el CH4, pues es también absorbido y metabolizado por los organismos metanogénicos y metanótrofos. A pesar del elevado número de estudios que analizan el impacto del biochar en suelos anóxicos, son pocos los experimentos que han evaluado su efecto en suelos agrícolas típicos de clima mediterráneo como el español: suelos básicos y con un régimen de riego escaso. Se presentan los resultados preliminares de un estudio pormenorizado del efecto redox del biochar en la producción y oxidación de CH4, tanto biótica como abiótica, bajo distintos regímenes de humedad.Peer reviewe

Linking biochars properties to their capacity to modify aerobic CH4 oxidation in an upland agricultural soil

Aerobic soils are the largest biotic sink for atmospheric methane (CH4). Although agricultural intensification is known to adversely impact soil CH4 uptake, the application of organic amendments (e.g. composts, green residues) in agricultural soils has been found to stimulate the activity of CH4 oxidizers. However, little is known about the influence of biochar (a carbonaceous by-product of biomass pyrolysis) on the soil CH4 sink function. This study analyzes, through a series of laboratory incubation assays, how ten well-characterized biochars with contrasting properties influence CH4 oxidation rate constants (k) in an aerobic high-pH agricultural soil. Through the use of 13C-CH4, we demonstrated that both CH4 soil oxidation and CH4 assimilation were responsible for the decrease in CH4 concentration. A principal component regression (PCR) of the results suggested that the physico chemical properties of biochars were directly linked to their ability to enhance or inhibit the oxidation of CH4. Biochars from wood feedstocks and pyrolysed at 600 °C, characterized by a high pore area, led to the highest CH4 oxidation rates whereas biochars with high ash concentrations and electrical conductivity significantly diminished CH4 oxidation rates. Biochar redox properties were not found to be relevant for CH4 oxidation in soil.Peer reviewe

Fluorescein diacetate hydrolysis, respiration and microbial biomass in freshly amended soils

The hydrolysis of the fluorescein diacetate (FDA), related to several soil hydrolases, has been utilised to estimate the potential microbial activity of soil freshly amended with a wide range of organic amendments and compared to the size and activity of soil microflora, measured by the microbial biomass C (B C) and CO2 evolution, respectively. Three different composting mixtures at different phases of the composting process were added to a semi-arid soil and incubated for 2 months under laboratory conditions. The addition of the organic amendment immediately increased B C and both measures of microbial activity (FDA and CO2 evolution). Highly significant correlations were found between FDA hydrolysis and B C for soil amended with the three composting mixtures (r = 0.81–0.96; P < 0.01), regardless of the origin, composition and degree of stability of the organic amendments. FDA hydrolysis, conversely to CO2 evolution, was unaffected by the disturbance caused by the soil amendment, indicating that the two parameters probably reflect different aspects of soil microbial activity. FDA hydrolysis could serve as an alternative estimation of the microbial biomass in freshly amended soils, despite the disturbance caused by the exogenous organic matter.This research was supported by a grant from the Italian Ministry for Agricultural, Food and Forestry Policies (MiPAAF), Finalized Project PANDA and the research project Ref. CTM2005-05324 financed by the Spanish Comisión Interministerial de Ciencia y Tecnología (CICYT).Peer reviewe