Paper details

Title:

Long-Term Effects of Nitrogen Fertilization on Giant Reed (Arundo Donax L.) Biomass Productivity

Author(s):

Zegada-Lizarazu, W., Pritoni, G., Monti, A.

Document(s):

Abstract:

Proper soil fertility maintenance is an issue of significant importance because of its impacts on crop productivity, production costs, and on the environment. The objective of the present study was to determine the long­term effects (13 years) of several nitrogen fertilization doses on the aboveground biomass production of giant reed. A local ecotype of giant reed was planted in 1997 in Bologna (Italy) at a density of one plant per square meter. Every year, starting from the second one, four nitrogen fertilization rates were applied: 0 (N0, unfertilized control), 80 (N80), 160 (N160), and 80+80 (N80+80) kg N ha-1. Nitrogen was applied one week after 50% of re-sprouting in the N80 and N160 treatments, while in the N80+80 treatment, nitrogen application was split in two: 80 kg N ha-1 were applied at the same time as in the previous treatments, while the remaining dose was applied two weeks later. Winter harvests were done manually and aboveground dry matter was determined. Also plant height and basal stalk diameter were measured. The unfertilized plants reached their maximum productivity (23.4 Mg ha-1) on the 4th year after planting (one year earlier than in the fertilized plots), afterwards a quasi-continuous yield reduction up to 10.8 Mg ha-1 was observed. On the other hand, in the N160 and N80+80 treatments productivity was characterized by two yielding phases: in the first one maximum yields (between 26.1 and 27.7 Mg ha-1) were obtained on the 5th year, then yields reduced in the next two years. During the second phase biomass production increased again from the 8th to 10th year of growth, but with somewhat lower values than in the first phase, then productivity declined towards the last harvest, reaching values similar or even lower than in the establishment year. These results suggest that high fertilization rates sustained yields over 20 Mg ha-1 for a productive cycle of about 8 years. If no fertilization is applied the high yielding production cycle is circumscribed to about 3 years only.

Keywords:

biomass, energy crops, nitrogen, productivity, agronomy

Topic:

Biomass Resources

Subtopic:

Energy crops (session 3)

Event:

19th European Biomass Conference and Exhibition

Session:

OC1.2

Pages:

152 - 156

ISBN-13:

978-88-89407-55-4

ISBN-10:

88-89407-55-7

Paper DOI:

10.5071/19thEUBCE2011-OC1.2

Price:

FREE