Introduction to Ecological Risk Assessment - Dealing with Contaminated Sites: From Theory Towards Practical Application - page 583

is thought to be so high that the loss of some species might not result in func-
tion loss, although the relevance of microorganisms in soil is an issue which
remains controversial in the international research community (Emmerling et al.
2002 ).
However, human life in a modern civilization, in its present form, would be
impossible without a healthy soil ecosystem. Without a sound soil Ecological
Health, the foundations of our social and economic systems would be undermined.
From this perspective, the soil ecosystem has a tremendous economical significance.
However, many of the services provided by ecosystems do not have an explicit value
in our conventional market economy (Daily et al. 2000 ), and therefore environment
and economy are still unequal partners (European Environment Agency 2008 ). But
Ecological tests are used, such as ecosystem accounts, to describe the way ecosys-
tems perform. However, it could be beneficial if some kind of monetary price could
be attributed to Ecosystem Services. This would offer decision-makers the possibil-
ity to be able to weigh the value of Ecosystem Services alongside other social and
economic information.
In 1997, the economic value of Biodiversity in general was calculated, resulting
in the conclusion that it was two times the gross national product of the whole world
(Costanza et al. 1997 ). In addition, in the Millennium Ecosystem Assessment very
high values for Ecosystem Services were reported (UNEP 2005 ). The economic
value of Ecosystem Services is still under discussion, but it is clear that it is very
significant.
As mentioned in Section 13.1.3 , the amazing performance of the soil ecosystem
is largely unknown to the general public. Even with decision-makers dealing with
contaminated sites, there is often confusion about the exact role of organisms in the
soil, and the extent to which they fulfil their tasks. They generally realize, though,
that human life is better off with a healthy soil ecosystem. Many decision-makers
know about the functions that the soil ecosystem performs. However, not all are
aware of the entirety of these functions and the powerful production for which these
organisms are responsible.
13.4.2 Biodiversity
Biodiversity is the variety of life, in other words, the variety of the ecosystems,
species and their genes. The definition of Biodiversity relates to the whole ecosys-
tem of which the organisms are a part. In general, Biodiversity is approached from
the perspective of its intrinsic value, that is, the significance of the entity by itself,
independent of direct or indirect advantages for mankind. Typically, Biodiversity is
assessed in terms of numbers of species. With the purpose to stress the importance
of the concept, the United Nations declared 2010 to be the International Year of
Biodiversity , giving space to celebrations in at least 80 countries, listed in UNEP
Convention of Biological Diversity ( 2010 ).
It is generally acknowledged that Biodiversity has decreased during the last few
decades. Therefore, the decline in Biodiversity is one of the eight threats mentioned