Las potencialidades bioenergéticas del Arundo donax L. en Argentina

Las iniciativas que estimulan el aprovechamiento de recursos renovables para sustituir fuentes fósiles en pos de la transición energética ganan visibilidad en un contexto de calentamiento global, principal desafío ambiental planetario. El objetivo de este artículo es analizar las barreras y las oportunidades de generar bioenergía térmica a partir de la caña de Castilla (Arundo donax L.) como recurso para diversificar la matriz. Se aplicó un enfoque integral técnico para evaluar las potencialidades energéticas del Arundo donax L., planta herbácea de origen asiático, considerada una especie de buen rendimiento de biomasa por hectárea. Aplicando diseños en bloques al azar y técnicas estandarizadas, se realizaron ensayos agronómicos en el SE de la provincia de Buenos Aires. Se obtuvieron rendimientos entre 5 y 11 t/ha, superiores a mayor densidad de plantación. Las características tecnológicas de la biomasa mostraron un contenido promedio de celulosa de 53 % y un poder calorífico superior entre 4000 y 4500 kcal/kg, lo que confirma su potencial como cultivo energético. Los resultados sobre la producción y el uso de la biomasa demostraron que se dispone de las capacidades tecnológicas para su explotación, sin impactar en los suelos y aprovechando su potencialidad como recurso energético renovable. Se reflexiona acerca de la cadena de valorización de la especie que permita promover procesos de localización de proyectos que activen complementariedades entre territorios singulares. Abstract Initiatives that stimulate the use of renewable resources to replace fossil sources in pursuit of the energy transition gain visibility in the context of global warming, the main planetary environmental challenge. In the study, a comprehensive technical approach was applied to evaluate the energy potential of Giant reed (Arundo donax L.), a herbaceous plant of Asian origin, considered a species of good biomass yield per hectare. From randomized block designs and standardized techniques, agronomic trials were carried out in the SE of the Province of Buenos Aires, obtaining yields between 5 and 11 t/ha, higher at higher planting density. The technological characteristics of the biomass showed an average cellulose content of 53 % and a higher calorific value between 4000 and 4500 kcal/kg, confirming its potential as an energy crop. The results on the production and use of the biomass demonstrated the availability of technological capacities for its exploitation without impacting soils and taking advantage of its potential as a renewable energy resource. Thus, we reflect on the value chain of the species that allows promoting localization processes of projects that activate complementarities between singular territories.

Performance of a Pilot-Scale Constructed Wetland and Medium-Term Effects of Treated Wastewater Irrigation of Arundo donax L. on Soil and Plant Parameters

On marginal lands in the Mediterranean basin, giant reed (Arundo donax L.) represents one of the most interesting perennial crops due to high levels of biomass production. Considering periodic water shortage during the summer months in this area, the reuse of treated wastewater (TWW) would seem to be a good opportunity for the growth of the species. The aim of this study was to assess the medium-term effects of irrigation using freshwater (FW) and TWW on soil characteristics and growth in giant reed plants. TWW was obtained from a pilot-scale horizontal subsurface flow constructed wetland system (HSSF CWs) with a total surface area of 100 m2. A split-plot design for a two-factor experiment was used with three replications. Medium-term TWW irrigation increased organic matter and plant nutrients in the soil; however, pH was not affected. Plants irrigated with TWW showed greater growth (+10.49% in height, +12.75% in stem diameter, +11.51% in above-ground biomass) than those irrigated with FW. The higher heating value of crop residues ranged between 16.83 (FW-irrigated plants) and 17.00 MJ kg−1 (TWW-irrigated plants). Results show that HSSF CWs produces TWW, which can be an alternative source of water for growing giant reed with high biomass performance.