Nitrate Uptake by Terrestrial and Aquatic Plants - Illinois ...

Figure 3. Uptake of Nitrate by Corn and by
Switchgrass.
Its long fibrous roots, which
extend deeper into the soil than
those of most crop species, may
be key for use in effective
agricultural buffer zones (Huang et
al., 1996).
Switchgrass has also recently
attracted attention as a cash crop.
It is being grown in mass
quantities as a potential fossil fuel
replacement species. Preliminary
studies have shown that
switchgrass can be effectively co-
Figure 5. Switchgrass
(Panicum virgatum).
Switchgrass (Fig. 5) is a native North
American warm-season grass that can grow
up to three meters in height on marginal
lands, requires little or no fertilization and
irrigation, and is resistant to drought. It
has recently attracted attention as a
biomass-filter type plant in agricultural
applications. For example, a 5-M-wide
strip placed below a dairy manure lagoon
effluent removed 76% of total N and 47%
of total P (Sanderson et al., 2001). It was
much more effective than cool-season filter
strips in nutrient removal (Lee et al., 1998).
Figure 4. Uptake of Nitrate by the Floating Aquatic Plant,
Hornwort.
fired with coal in power plants (McLaughlin and Walsh, 1998).
Other potential uses for switchgrass are for ethanol production
(Lynd et al., 1991) and incorporation into mulches, fiberboard,
and paper products (Radiotis et al., 1999).
The floating aquatic species, hornwort (Fig. 6), also was
effective. Hornwort is a native plant that is found in ponds and
slow-flowing streams throughout Illinois, and is also grown for
use as a decorative species for water gardens and aquariums. It
can occur at considerable depths in a lake or pond, and lives
throughout the winter, able to photosynthesize even under ice
cover.
In an experiment in which the initial nitrate concentration was
350 ppm, it reduced the concentration to 75 ppm in nine days,
corresponding to a half-life of 4-5 days. It removed on average