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Phytotechnology with Biomass Production
toxic substances, salts, and other contaminants may be present. When using
organic amendments at a new site where vegetation is being established,
there may be a need to add soil fauna to enhance biodiversity.
In some applications of phytotechnology, there is a need to improve the biological state of the soil in order to improve soil health. The well-developed soil
ecosystem includes about four trophic levels of organisms. Archaea, bacteria,
fungi, actinomycetes, and algae provide ecosystem services by degrading
organic compounds and making nutrients more available to plants. These are
very small microorganisms of the order of 1 μm. Microfauna include protists
(protozoa) and small nematodes that consume bacteria and other microorganisms. The microfauna are frequently larger than 2 μm and often less than
1 mm. There are soil mesofauna such as arthropods (insects), mites (acari),
larger nematodes, and rotifera that are often in the size range between 0.1
and 5 mm. Macrofauna are about 1–50 mm in size and include earthworms,
termites, spiders, and isopods (Whalen & Sampedro, 2010). Earthworms are
very beneficial; they improve the texture of soil and nutrient cycling.
Although not conducted on a contaminated site, research comparing
perennial crops such as miscanthus (Miscanthus sacchariflorus) and switchgrass (Panicum virgatum L.) with annual crops such as maize (Zea mays L.) and
sorghum [Sorghum bicolor (L.) Moench] as potential cellulosic biofuel feedstocks illustrates the potential for achieving production and soil health goals
simultaneously. Ethanol production potential of the perennial crops was less
than that of the annual crops but still surpassed 3 m 3 ha −1 year −1 averaged over
10 years in the Central Great Plains of the US (Roozeboom et al., 2019). In
that time, soil organic carbon increased in the 0–15 cm soil depth beneath
perennial crops by 0.8–1.3 Mg C ha −1 year −1 (McGowan et al., 2019). Greater
soil organic carbon was associated with improvements in several parameters
generally associated with greater soil health: root biomass, abundance of
arbuscular mycorrhizae and saprophytic fungi, and soil aggregation, which
is also associated with reduced soil loss.
6.6 Conclusions
Soil health and soil quality are very important because ecosystem services
such as crop yields are greater when soil health is very good. In applications
of phytoremediation with biomass production, it is beneficial to have multiple
goals to reduce the effects of the contamination on soil health and to improve
soil health and biomass productivity. Soil amendments that add organic carbon and living organisms may help to improve soil health, plant growth, and
nutrient cycling. Education is generally of significant value because of the
complexity of soil ecosystems and the many properties of soils that affect soil
health and ecosystem services.
Phytotechnology with Biomass Production
toxic substances, salts, and other contaminants may be present. When using
organic amendments at a new site where vegetation is being established,
there may be a need to add soil fauna to enhance biodiversity.
In some applications of phytotechnology, there is a need to improve the biological state of the soil in order to improve soil health. The well-developed soil
ecosystem includes about four trophic levels of organisms. Archaea, bacteria,
fungi, actinomycetes, and algae provide ecosystem services by degrading
organic compounds and making nutrients more available to plants. These are
very small microorganisms of the order of 1 μm. Microfauna include protists
(protozoa) and small nematodes that consume bacteria and other microorganisms. The microfauna are frequently larger than 2 μm and often less than
1 mm. There are soil mesofauna such as arthropods (insects), mites (acari),
larger nematodes, and rotifera that are often in the size range between 0.1
and 5 mm. Macrofauna are about 1–50 mm in size and include earthworms,
termites, spiders, and isopods (Whalen & Sampedro, 2010). Earthworms are
very beneficial; they improve the texture of soil and nutrient cycling.
Although not conducted on a contaminated site, research comparing
perennial crops such as miscanthus (Miscanthus sacchariflorus) and switchgrass (Panicum virgatum L.) with annual crops such as maize (Zea mays L.) and
sorghum [Sorghum bicolor (L.) Moench] as potential cellulosic biofuel feedstocks illustrates the potential for achieving production and soil health goals
simultaneously. Ethanol production potential of the perennial crops was less
than that of the annual crops but still surpassed 3 m 3 ha −1 year −1 averaged over
10 years in the Central Great Plains of the US (Roozeboom et al., 2019). In
that time, soil organic carbon increased in the 0–15 cm soil depth beneath
perennial crops by 0.8–1.3 Mg C ha −1 year −1 (McGowan et al., 2019). Greater
soil organic carbon was associated with improvements in several parameters
generally associated with greater soil health: root biomass, abundance of
arbuscular mycorrhizae and saprophytic fungi, and soil aggregation, which
is also associated with reduced soil loss.
6.6 Conclusions
Soil health and soil quality are very important because ecosystem services
such as crop yields are greater when soil health is very good. In applications
of phytoremediation with biomass production, it is beneficial to have multiple
goals to reduce the effects of the contamination on soil health and to improve
soil health and biomass productivity. Soil amendments that add organic carbon and living organisms may help to improve soil health, plant growth, and
nutrient cycling. Education is generally of significant value because of the
complexity of soil ecosystems and the many properties of soils that affect soil
health and ecosystem services.