Page 234 - Materials Chemistry, Second Edition

ACCOUNTING FOR ECOSYSTEM GOODS AND SERVICES 221

Table 9.2 Eco-LCA ecosystem services.
Provisioning Services Regulating Services Supporting Services

Fossil Fuels Air Quality Regulation Soil Formation
(partially)

Minerals Erosion Regulation Photosynthesis
(partially)

Renewable Energy Water Purification Nitrogen Cycling
(partially)

Land Waste Processing Carbon Cycling
(partially)

Timber Pollination (partially) Primary Production
(partially)

FreshWater Water Cycling (partially)
Wild Fish & Aquaculture
(partially)
Biomass Fuel (partially)

Crops, Livestock, & Fiber
(indirectly)

exergy total for a product is also the same as the ecological cumulative exergy
consumption, or emergy. This is all of the exergy from industrial and eco-
logical processes that is required to make that product. All of this cumulative
exergy is put into units of solar emjoules, or sej. According to emergy theory,
the sej allows the difference in energy quality to be accounted for in different
resources. For example, 1 joule of sunlight may appear to be equal to 1 joule of
wind since they are both a single joule; in fact, the joule of wind is equivalent
to 1500 sej, while the joule of sunlight is equal to 1 sej. It therefore requires 1500
joules of sunlight to do the work of 1 joule of wind. The factors that are used to
convert from the original energy unit to sej are called transformities and will
always indicate how many sej are required to get a single joule of the product
(Ultiati, 2004).
Exergy and emergy are not the only ways to draw conclusions from the
ecosystem goods and services that have such varying units. One could com-
pare the percentage of required resources that are energy versus materials. The
comparison of renewable versus nonrenewable would be another good option.
There are also different metrics that can be compared such as the sustainability
index, which is a measure of both renewability and yield. Of course, while
these various forms of aggregated results lead to data that is much simpler to
compare, there is always the risk that a loss of information through aggrega-
tion will lead to poor decision making; therefore, it is best to make decisions