A SALIX SPP. SHORT ROTATION COPPICE SYSTEM IN BUENOS AIRES, ARGENTINA: EFFECTS OF CLONAL COMPOSITION, PLANTING DENSITY AND DRIP IRRIGATION ON BIOMASS PRODUCTION.

DOFFO, GUILLERMO; ACHINELLI, FABIO; LUQUEZ, VIRGINIA; ETCHEVERS P

Berlín

Congreso; IPC 2016; 2016

IPC-FAO

In Argentina, renewable sources represent 9.4% of the primary energetic matrix, of which only 5% correspond to bioenergy sources. During the last decade, the country needed to increase fossil fuel imports due to a pronounced fall in national reserves. As a consequence, there is a growing interest from government and companies about the use of wood biomass to produce energy through firing or co-firing processes. One obstacle for the development of these projects is the scarcity of information about the local productivity of dendroenergy crops, and about the suitability of this biomass to produce energy. We established a tree-factor factorial field trial with a willow (Salix spp.) short rotation coppice system (SRC) to evaluate the effects of drip irrigation, genotype and planting density on the yield and quality of the biomass. The eight treatments were arranged in a split-split plot design and replicated in three complete blocks. The trial was planted on an agricultural soil in September, 2012 and harvested every year from 2013 to 2015. The variables determined for each treatment were yield (t/ha dry mass at 105°C), lower heating value (LHV, cal/g) and total ash content (TAC, %). During the first season (September 2012-April 2013) drip irrigation was not applied because soil was saturated or at field capacity for most of the growing period. Clone Salix alba `Yaguarete INTA-CIEF´ had significantly higher yields than clone Salix matsudana x Salix alba `Barrett 13-44 INTA´ (11.94 ± 0.88 t/ha vs. 9.49 ± 1.14 t/ha). The increase of plantation density from 13333 plants/ha to 20000 plants/ha correlated with higher yields, but the effect was statistically significant only in plots of clone Barrett 13-44. In the two following years, drip irrigation was applied to irrigated plots, with resulted in the addition of 543 mm (2013-2014) and 843 mm of water (2014-1015) to rainwater. In both seasons irrigation was the only factor with statistically significant effects on biomass production, where irrigated plots produced higher yields compared to non-irrigated ones (21.76 ± 0.98 t/ha vs. 16.94 ± 1.07 t/ha during 2013 ? 2014 season; 19.03 ± 1.48 t/ha vs. 11.99 ± 1.22 t/ha during 2014 ? 2015 season). LHV and TAC were determined on 2013-2014 harvest only. The mean LHV for all samples was 4654 ± 25.5 cal/g, with no significant differences between treatments, while for TAC marginally significant differences (0,05