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3.3.8 NUTRIFICATION
Emission of salt nutrients by human activities involves a big impact in the environ-
ment. The eutrophication process in lakes, watercourses, and open coastal waters is
due to excessive quantities of nutrient salts emitted by man and consequently results
in increased production of planktonic algae and aquatic plants, which leads to a
reduction in the quality of water. The process of decomposition of dead algae
consumes important oxygen and causes with a loss of water quality. Agriculture has
been identified as the most significant source of nitrogen loading. Wastewater treat-
ment plants and fish farming are the most predominant causes of phosphorus emis-
sions.

3.4 AREAS OF PROTECTION

The set of category indicators resulting from the life-cycle inventory configures and
defines the environmental diagnosis associated with product manufacture or any
other activity. The impact indicators are associated with environmental damages
corresponding to areas of protection (AoP) or sectors of the environment to be
protected.
In the first report of the Second SETAC Working Group on Life-Cycle Impact
Assessment (Udo de Haes et al., 1999), an AoP was defined as a class of category
endpoints. In ISO 14042 three of these classes are mentioned: human health, natural
environment and natural resources. Another term used is the expressive “safeguard
subject” introduced by Steen and Ryding (1992). It is important to note that these
two terms convey the same message: they relate to the category endpoints as physical
elements, not as societal values. Thus, following this terminology, the human right
to life or economic welfare cannot be an AoP or a safeguard subject; neither can
respect for nature or cultural values.
However, the concept of AoPs enables a clear link with the societal values that
are the basis for the protection of the endpoints concerned. Table 3.5 gives an

TABLE 3.5
Assignment of Societal Values to AoP
Societal values Human/manmade Natural

Intrinsic values Human health Natural environment (biodiversity
Manmade environment (landscapes, and natural landscapes)
monuments, works of art)
Functional values Manmade environment (materials, Natural environment (natural
buildings, crops, livestock) resources)
Natural environment (life support
functions)
Source: Reprinted with permission from Udo de Haes, H.A. and Lindeijer, E., in Towards Best Available
Practice in Life-Cycle Impact Assessment, Udo de Haes et al., ©2001 SETAC Press, Pensacola, FL.

© 2004 CRC Press LLC