Page 263 - Materials Chemistry, Second Edition

10 Life Cycle Impact Assessment 249

considered a local impact category in LCA, in opposition to other impact categories
of global geographic scope such as climate change, whose environmental effects (in
terms of radiative forcing) are independent of the location of the emission.
As a consequence of the above explanation, methods that focus on land-use
impacts should include geospatial data both in the LCI and the LCIA phases. The
inventory must contain information on the geographic location of the human
intervention, with a level of detail that may vary from the exact coordinates to
coarser scales (e.g. biome, country, continent), depending on the goal and scope of
the study and if the inventory refers to the foreground or to the background system
(see Chap. 9). In the LCIA, characterisation factors for a given impact indicator
must capture the sensitivity of the habitat to the impact modelled. For example,
characterisation factors for soil erosion may include information on the soil depth in
the specific location of the activity under evaluation, as the impact of soil loss will
depend on the soil stock size, i.e. thinner soils are more vulnerable than thicker soils
(Núñez et al. 2013). Every geographic unit of regionalised impact assessment
methods has its own characterisation factor. Within the boundary of such a unit, it is
assumed that an activity triggers the same impacts on land.

10.14.3 Existing Characterisation Models

Characterisation of land use in LCA has been extensively discussed over the last
decades but is far from being settled, because the first operational methods have
only been available since 2010. Until then, land use was only an inventory flow-
2
counted in units of surface occupied and time of occupation (m and years) and
2
surface transformed (m ), without any associated impact. The main reason for this
“late development” is that land-use related impacts rely on spatial and temporal
conditions where the evaluated activity takes place, whereas traditional LCA is
site-generic. During the last few years, the release of geographical information
system (GIS) software and data sets have brought new opportunities in LCA to
model land-use impacts and in general, any other spatially dependent impact
category.
Today, there are LCIA methods to evaluate impacts on biodiversity and impacts
on several ecosystem services. From the long list of services provided by terrestrial
ecosystems (24 acknowledged in the Millennium Ecosystem Assessment interna-
tional work programme (2005), LCA focuses on those which are recognised as
being more environmentally relevant (i.e. educational and spiritual values are
excluded). A non-exhaustive list of methods is provided below. For completeness,
see Milà i Canals and de Baan (2015):
• Impacts on biodiversity: Biodiversity should be preserved because of its
intrinsic value. The most commonly applied indicator is based on species
richness, given the availability of data (Scholz 2007; Koellner and Scholz 2008;
de Baan et al. 2013a, b). Damage on biodiversity is commonly expressed in