GI
111
Chapter 9 . Macroinvertebrate and Stream Habitat Relationships
187
9.4.2
Discovery of Contradictory Relationships
Even though most sensitivity results revealed relationships complementary to
literature findings, only some results where contradictory as shown in Fig. 9.9.
Giller and Malmqvist (1998) observed that the majority of Dugesiidae (triclads)
that live in streams are cold-living species. However the sensitivity curve in Fig.
9.9a shows for Queensland streams that Dugesiidae were only present at water
temperatures of more than 20°e.
Libellulidae are of tropical origin but the sensitivity curve in Fig. 9.9b indicates
their absence at latitudes above -20(S) in Queensland streams, which characterise
tropical zones of Queensland.
08
0.8
GI
GI
~06
111
;g 0.6
b
·iii
.=
&04
11 0.4
:::I
0
:::i
02
0.2
0
5
10
15
2)
25
3J
:E
-35
-30
-25
-20
-15
-10
WEr ErTperaIue (oC)
Latitude (5) Decimal
0.8
0.8
GI
111
~ 0.6
c
:E0.6
u
IIJ
IIJ
So
~0.4
0 0.4
0.2
0.2
0
0
-35
-30
-25
-20
-15
-10
3
5
7
9
Latitude (5) Decimal
Stream Order
Fig. 9.9. Relationships of a) Dugesiidae occurrence with water temperature, b)
Libellulidae occurrence with latitude, c) Dytiscidae occurrence with latitude and
d) Dytiscidae occurrence with stream order as discovered by sensitivity analysis
) Dytiscidae occurrence with stream order as discovered by sensitivity analysis.