50440
* 3 0 f
2 0 f
Soil surface
V^_^ \
...
N.
"—^/'i
20
24
1 ' 1 ' ' ■ 1 ■ ' ■ 1 ' '
f,
M —
/r
■ ' I i '
Hamada
—v
\
\ \ ·
\ \
1 1 ' ' ' I
20
Time (hours)
8
12
Time (hours)
Fig. 3. (a) Temperature changes of the soil surface, underground layers (at depths
of 5 and 20 cm) and of the air, during the day and night in a hamada (rocky substrata) Uromastix biotope. Data registered from May 7, 1967 at 8:00 P M to May 8,
1967 at 8:00 P M . (After C. Grenot, 1968a). (b) Temperature changes of the
soil surface, underground layers (at depths of 5 and 20 cm) and of the air, during
the day and night in an erg (sandy substrata); preferential biotope of Varanus
grise us. Data registered at the same time as those of ( a ) .