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Economics of Phytoremediation
community representatives, there is value in using methods and concepts
that are understood by all participants, especially when this leads to a good
remediation plan.
The System of Environmental Economic Accounting (SEEA) has been
developed to include the value of ecosystems in evaluating contaminated
sites; the system includes the ability to include soil quality and carbon
sequestration in ecosystem accounting (Hein et al., 2020; SEEA, 2014). Natural
capital has value for society, and there is a global effort to extend accounting
to include the value of ecosystems so that site remediation benefits can be
fully communicated.
9.3 Benefits of Remediation
The total amount of land with contaminated soil is great. Values in the literature include that 28.3% of the land area in Europe has soil contamination
(Ben Fradj et al., 2020), and more than 20 million ha worldwide are contaminated (Evangelou et al., 2012). The estimated amount in the United States
is about 9 million ha (U.S. EPA, 2011). In addition, there are between 1 and
6 billion ha of degraded soil that need to have soil organic matter added to
improve soil quality and land productivity (Rumpel et al., 2018).
As population increases it becomes more important to remediate contaminated sites and use the land for beneficial purposes. There are many benefits
associated with converting an unused contaminated site into a site that is used
for biomass production. By addressing the contamination such that risk is
reduced, the site can be used with vegetation to consume carbon dioxide and
produce oxygen and plant biomass that can be used by society. Soil quality
and soil health can be improved by adding soil amendments such as manure
and/or biosolids from wastewater treatment to increase soil organic carbon.
There is value to establishing Miscanthus or another biomass crop on the
site that produces a useful product and adds soil carbon to the root zone.
Soil organic carbon improves nutrient cycling, the ecological functioning of
the organisms in the root zone soil, and the water holding capacity of the
soil (Lal, 2016). Better soil health is one of the major ecosystem benefits of
phytoremediation with biomass production.
The increase in soil carbon in the root zone has value with respect to carbon sequestration for the global carbon balance and Paris agreement on climate change. At sites with metals in the soil, adding organic carbon to soil
reduces the availability of the metals.
The benefits of phytoremediation include the aesthetic value of a green
site that provides better habitat for native wildlife compared to the site prior
to remediation. Ornamental vegetation can be used for phytoremediation
where parks or arboretums are established for public use and enjoyment