LCA Food 2012 in Saint Malo, France! - Manifestations et colloques ...

GROUP 4, SESSION B: CROP PRODUCTION SYSTEMS 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
114. Effects of different crop management on durum wheat GHGs
emission
Salem Alhajj ali 1,* , Giuseppe De Mastro 1 , Luigi Tedone 1 , Stefano Bona 2 , Lucia Coletto 2
1 University of Bari - Dipt of agricultural and environmental science, Via Amendola, 165/A - 70126, Italy, 2
University of Padova – Dipt. of agronomy, Viale dell’Uuniversità 16, 35020, Legnaro, PD, Italy, Corresponding
author. E-mail: salem_grb@yahoo.com
Having all the impacts, associated with different management typology of the agro-ecosystem, assessed
through the use of LCA methodology according to an implementation of the data collected directly from the
field to minimise data uncertainties, could be a very sensitive model which can support the current political
action plans for reduction of the impacts which lead to the environmental effects. Moreover, the use of this
kind of model to identify more sustainable combination of agricultural practices could satisfy the agronomists,
economists as well as environmentalists once the productivity of the system is being maintained with
as low inputs and emissions as possible.
For that, an on farm field trial in Southern Italy (Basilicata Region) was conducted to evaluate alternative
agricultural practices that could help farmers to reduce reliance on fossil fuel, lower the input costs and decrease
the GHG emissions of durum wheat production systems through life cycle assessment (LCA) method.
The focus of this study was specially oriented to the potential GHGs emitted (expressed as CO2-eq) as a consequence
of the different levels of soil tillage (intensive (IT), reduced (RT) and conservative (CT) combined
with different nitrogen fertilisation rates (90, 60, 30, 0 kg N ha-¹ as urea). A special attention was given to
grain yield as this represents the main farmers’ objective and was being further correlated to the emissions.
The LCA analysis considered the entire system of the field experiment in which each treatment was replicated
three times and the farm gate was considered as the system boundary. Inventory data of all agricultural
operations in the field including tillage, seeding, fertilisation, herbicide application and harvesting, have been
collected. Then, all data were used to estimate and compare (Through SimaPro 7.3 using the IPCC 2007
GWP 100a method for comparison) the impacts of different wheat production systems. Furthermore, in spit
of all the data collected directly from the field, nitrogen balance was also calculated as the differences between
nitrogen inputs and outputs of total nitrogen in the soil, grain, straw and plant residues sampled.
This study showed that there was a higher proportion of energy consumption and GHG emissions attributed
to N fertiliser and to the ploughing operations for the production of wheat. The GHG emissions of different
wheat production systems showed statistically significant differences within the treatments (tillage and N
fertiliser rate), but no significant differences found in the interaction between tillage and N fertiliser applications.
Going deep into the analysis, we found that the highest CO2-eq emissions was reported in the intensive tillage
(IT) with 90 kg N ha-¹ mainly because of the high emissions associated with the fertiliser and fuel production.
The overall emissions were lower in conservation tillage (CT) and in reduced tillage (RT) systems
compared by intensive tillage (IT) system due to the diesel fuel consumption which resulted from the high
number of field operations.
On the basis of this first year of activity, conservation tillage (CT), represent a more environmentallyfriendly
system of wheat cultivation, which could sequester more CO2, and as a consequence gave lower
emissions and impact on the environment than both other systems. In contrast, intensive tillage (IT) was the
worst in all scenarios.
825