Honestly I cant even tell if theyre talking about dwc or aero. I know dwc would hold very little oxygen at that level, but if you can get enough airflow through stones it would still be fine, the plants get plenty of oxygen directly from the bubbles, not DO.
http://www.plantphysiol.org/content/73/1/46.full.pdf
Based on fresh and dry weight and leaf area,
the optimal
root-zone temperature for seedlin growth was 30°C. The carbon exchange
rate of the leaves was also found to increase with rising root-zone
temperature up to 30°C. However, a more complex relationship seems to
exist between root-zone temperature and the accumulation of 14C-labeled
assimilates in the roots; inasmuch as there is no enhancemnt in this
accumulation at the most growth promoting root-zone temperatures (22-
300C).
Tomato seeds (Lycopersicon esculentum Mill. cv Vendor) sown
in vermiculite were pricked out after 2 weeks and inserted
through cylindrical holes drilled in 4-cm-thick styrofoam. The
seedlings were secured in place with a ring of soft clay which
formed an insulating seal between the plant shoot and plant root.
With the cotyledons emerging from above and the roots hanging
from below, the styrofoam was fitted tightly into a plastic bin
containing 22 L of half-strength Hoagland solution (pH 6.0).
The nutrient solution was thermostatically controlled to ± 0.5°C
of the desired temperature and was kept at maximum level by
adding half-strength Hoagland solution. The temperature of the
solution had no effect on the temperature of the seedling shoot.
Growth. Tomato plants grown for 2 weeks in a range of rootzone
temperatures
showed an increase in growth as the root
temperatures increased from 10°C to 30C, with a precipitous
decrease in growth above 32.2°C (Fig. 1).
This is in agreement
with published results (5, 16, 17, 19).
