Geoscience Reference
In-Depth Information
Table 12.5
(
Continued
)
TWINSPAN GROUP
A
B
C
D
E
F
Watercourse
retention
small dikes
no retention
no retention
small dikes
small dikes
large dikes/dams
Water pollution
some solid detritus,
small algal blooms
low pollution from
cattle presence
low pollution from
cattle presence
and traditional
agriculture
Very low pollution
from traditional
agriculture
domestic and
agricultural inputs,
some algal growth
high levels of
turbidity and
domestic/industrial
detritus, algal
blooms
Average water
pH
7.5
5.8
6.3
6.7
6.8
6.8
Average water
conductivity
454
29
22
32
56
369
scm
−1
Average water
temperature
◦
C
17.5
14.2
15.1
15.3
17.2
19.4
Conservation of
surrounding
natural
vegetation
some disturbance
highly preserved
highly preserved
some disturbance
some disturbance
highly disturbed
Average
percentage of
shaded
watercourse
11
5
32
56
23
20
Local average
insolation
hyr
−1
2101 to 2200
1901 to 2000
2101 to 2200
2101 to 2200
2001 to 2100
2101 to 2200
Local average
temperature
◦
C
15.1 to 17.5
10.1 to 12.5
10.1 to 12.5
10.1 to 12.5
10.1 to 12.5
12.6 to 15
Local total
precipitation
mm yr
−1
1001 to 1200
1081 to 2000
2001 to 2200
2201 to 2400
1601 to 1800
1401 to 1600
