32
25
.c 20
.. ':..
- ."
o c:
... ,15
c: ..
0,
<:: a
E - 10
.- x
a. ..
:l a
a:: ~ 5
",..a--,
,
\
a . . . . '
\
,
\
"
I
..... ""
,
,
o~~~~~--~--~--~--~~
o
10
15
20
25
30
35
Temperature ('C)
Respiratory Metabolism
Fig. 3 .... The dependence of respiration rate on temperature in
immature (dashed line) and mature (solid line) Onychiurus meridiatus. (Argyropoulou and Stamou
1993).
acclimated to constant temperature, the lower estimates of b were made at the
limits of the temperature gradients. Hence, the effect of live weight on respiratory activity was reduced under a changing thermal regime (from fluctuating
to constant temperatures) and at temperatures beyond the thermal range that
the animals normally experience. Changing temperatures clearly increase the
efficiency of energy transformation in Mediterranean arthropods.
3.2
Respiratory Response to Varying Temperature
Left skewed graphs describing the dependence of different physiological or
activity parameters on temperature have been provided for arthropods living
in other extreme environments. Such data have been reported, for example,
for the Antarctic springtails Cryptopygus antarcticus and Parisotoma octooculata by Block et al. (1990) and Block (1996). However, these authors exploited only the parts of their experimental data fitting exponential curves.
Data regarding the dependence of Mediterranean collembolan and oribatid metabolism on temperature were exploited by fitting them to the model
proposed by Logan et al. (1976; Figs. 3.4, 3.5):
RR =a[(l+ke-prt _e(r-r\ll]
where RR = respiration rate, T = temperature in °C, p = rate of metabolism
increase up to the optimal temperature Topl (i.e. the temperature at which
maximum respiration is recorded), TM = lethal temperature, a = maximum
respiration rate, and k = a constant. Furthermore, the following ecologically
meaningful parameters can be estimated: the optimal temperature (ToPT), the
inflection point of the curve (Tinl1), and the critical temperature (Tcrl). Finally,
the optimum temperature range (OTR) within which changes in respiration
rate fluctuate slightly (±0.09) is arbitrarily defined.
25
.c 20
.. ':..
- ."
o c:
... ,15
c: ..
0,
<:: a
E - 10
.- x
a. ..
:l a
a:: ~ 5
",..a--,
,
\
a . . . . '
\
,
\
"
I
..... ""
,
,
o~~~~~--~--~--~--~~
o
10
15
20
25
30
35
Temperature ('C)
Respiratory Metabolism
Fig. 3 .... The dependence of respiration rate on temperature in
immature (dashed line) and mature (solid line) Onychiurus meridiatus. (Argyropoulou and Stamou
1993).
acclimated to constant temperature, the lower estimates of b were made at the
limits of the temperature gradients. Hence, the effect of live weight on respiratory activity was reduced under a changing thermal regime (from fluctuating
to constant temperatures) and at temperatures beyond the thermal range that
the animals normally experience. Changing temperatures clearly increase the
efficiency of energy transformation in Mediterranean arthropods.
3.2
Respiratory Response to Varying Temperature
Left skewed graphs describing the dependence of different physiological or
activity parameters on temperature have been provided for arthropods living
in other extreme environments. Such data have been reported, for example,
for the Antarctic springtails Cryptopygus antarcticus and Parisotoma octooculata by Block et al. (1990) and Block (1996). However, these authors exploited only the parts of their experimental data fitting exponential curves.
Data regarding the dependence of Mediterranean collembolan and oribatid metabolism on temperature were exploited by fitting them to the model
proposed by Logan et al. (1976; Figs. 3.4, 3.5):
RR =a[(l+ke-prt _e(r-r\ll]
where RR = respiration rate, T = temperature in °C, p = rate of metabolism
increase up to the optimal temperature Topl (i.e. the temperature at which
maximum respiration is recorded), TM = lethal temperature, a = maximum
respiration rate, and k = a constant. Furthermore, the following ecologically
meaningful parameters can be estimated: the optimal temperature (ToPT), the
inflection point of the curve (Tinl1), and the critical temperature (Tcrl). Finally,
the optimum temperature range (OTR) within which changes in respiration
rate fluctuate slightly (±0.09) is arbitrarily defined.