Ester McLaughlin wrote that acid rain projects often end up with plants
doing better in the acid rain and implied that this was not a good
experiment to run. However, at least for majors, perhaps this is the very
reason it should be run. I have several reasons for believing this:
1. I have found that students learn more from the experiments that don't
come out as they expect them to. When experiments "work" students just
take a "that's nice" attitude and don't give the experiment any thought,
but when their results are different, they begin asking why.
2. Acid rain can in fact benefit some plants. This is especially true
for the nitrogen-added acid rain because it acts as a fertilizer.
3. Acid rain in a pot won't have the same effect as in the ecosystem.
The acidity makes more things dissolve and in a pot could make some
nutrients more available, especially if the soil tends to be alkaline.
In nature, one danger is that these dissolved nutrients get leached from
the soil and carried away, whereas the undissolved nutrients (before acid
rain) remain in place.
4. Some plants do benefit from more acidic conditions. This is
particularly true of many moss taxa. Alkaline streams, as one example,
hold little CO2, whereas acid streams hold much more and therefore are
more hospitable to aquatic plants, many of which require CO2 and cannot
use bicarbonates.
5. Students need to see the dangers of short-term experiments and to be
able to evaluate the experiments done by time-driven consulting firms and
even some government contracts. "No harm" conclusions are often based on
just such short-term experiments, and with no experience in doing these,
our students and the general public are unaware of the dangers of these
experiments.
Now for the original question of where to get grasses, I know that
Miscanthus sinensis in Japan is able to grow on very acid soil around
geothermal vents. I know the species grows in this country, and my guess
is that it is very adaptable to pH differences. I don't know how easy it
is to obtain seeds. Perhaps your best bet is to obtain seeds from the
alkaline areas like Alberta, Canada, and acid areas like New Hampshire. A
local nursery might be able to help you.
Janice
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Janice M. Glime, Professor
Department of Biological Sciences
Michigan Technological University
Houghton, MI 49931-1295
jmglime at mtu.edu
906-487-2546
FAX 906-487-3167
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