Page 240 - Materials Chemistry, Second Edition

224 4 Life Cycle Impact Assessment

is complicated. Such procurement is, for example, done in the fishery for the
computation of fishing quotas. If biotic resources are important in an LCA,
adequate research on those is necessary.
World annual consumption(ta )− Formation rate(ta )
−1
−1
R (a )= (4.8)
−1
i World reserves(t)
The resource (i) is scarce if R > 0, if consumption exceeds the formation rate.
i
Only such resources should be evaluated as scarce. The resource scarcity factor is
calculated as in Section 4.5.1.2 for abiotic finite resources described in Equation 4.9:
R(biotic, scarce)= ∑ (m × R ), R > 0(kga ) (4.9)
−1
i i i
i
The formulas for worldwide shortage can mutatis mutandis also be applied
for smaller, approximately closed regions, for example, for a fresh water lake, a
marginal sea with small fluctuations or a closed jungle area if it is required by the
objective and scope of the LCA and if the data can be determined.
4.5.1.5 Use of (Fresh) Water
Fresh water is a regenerative abiotic resource, only in a few processes is it
irreversibly used (cement → concrete, hydrolyses). For some applications water
only gets heated (cooling in thermal power stations) or it supplies potential energy
(hydro-electric power plants). Evaporation (e.g. during irrigation for agricultural
use) withdraws water temporarily from human use, it is however not removed from
the geological cycle. It may rain down over land or into the sea, but also evaporate
from the surface of the sea and come down over land again. In reality the water
cycle is much more complicated than mentioned here (in a nutshell) and so are
the impacts of water. 117) In some countries water is abundant to an extent that no
consciousness on its (global) scarceness can be observed. Recently however the
regional scarcity of fresh water is a highly regarded topic and within the ISO 14000
series the standard ISO 14046 ‘water footprint’ was developed 118) (see below).
A scientific discussion on organisation and quantification of resources distin-
guishes 119) :
1. Deposits, no regeneration during a time span comparable to human lifetimes
(e.g. minerals, fossil energy carriers and raw materials).
2. Funds, these are resources that regenerate within relatively short times (within
the measure of human life times) (e.g. game and wild plants and cultivated
forests belong to the technosphere).
3. Flows, these are resources which continuously regenerate (e.g. wind and solar
radiation).
Water can be part of each category depending on local/regional issues: fossil
groundwater belongs to deposits, non-fossil groundwater to funds, surface water,

117) Mil´ a i Canals et al. (2009), Pfister et al. (2009) and Berger and Finkbeiner (2010).
118) ISO/DIS 14046: 2013. Environmental management – Water footprint – Principles, requirements
and guidelines.
119) Guin´ ee et al. (2002) and Udo de Haes et al. (2002).