Page 95 - Materials Chemistry, Second Edition

82 Part 2a: Guide

4.3.3.11 Eutrophication

Topic

Eutrophication covers all potential impacts of excessively high environmental levels of
macronutrients, the most important of which are nitrogen (N) and phosphorus (P). Nutrient
enrichment may cause an undesirable shift in species composition and elevated biomass
production in both aquatic and terrestrial ecosystems. In addition, high nutrient
concentrations may also render surface waters unacceptable as a source of drinking water.
In aquatic ecosystems increased biomass production may lead to a depressed oxygen
levels, because of the additional consumption of oxygen in biomass decomposition
(measured as BOD, biological oxygen demand). As emissions of degradable organic matter
have a similar impact, such emissions are also treated under the impact category
“eutrophication”. The areas of protection are the natural environment, natural resources and
the man-made environment.

Main choices and guidelines
Method status Characterisation method/factor Table in Part 2b
baseline generic EP 4.3.11.1
alternative average European EP 4.3.11.2
additional region (site) dependent EP 4.3.11.2
variant – –

Example (for baseline)

impact category eutrophication
LCI results emissions of nutrients to air, water and soil (in kg)
characterisation model the stoichiometric procedure, which identifies the equivalence
between N and P for both terrestrial and aquatic systems
category indicator deposition/N/P equivalents in biomass
characterisation factor eutrophication potential (EP) for each eutrophying emission to
air, water and soil ( in kg equivalents/kg emission)
unit of indicator result kg

4.3.3.12 Waste heat

Topic
Emissions of waste heat may increase temperatures on a local scale: in a city or lake, for
example. They cannot contribute to global warming on a scale such as that associated with
emissions of greenhouse gases. The effects on ecosystems of waste heat emissions to the
air are negligible. Depending on local conditions, the discharge of waste heat into surface
waters may result in a substantial temperature rise, with a consequent impact on local
aquatic ecosystems. In this Guide waste heat is treated as a separate impact category,
although it covers only aquatic emissions of waste heat such as cooling water emissions
from power stations. The areas of protection are the natural environment and natural
resources.