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Table 2 Characteristics of water and distribution of invertebrates along the transects obtained during larval surveys.

From: Agriculture and the promotion of insect pests: rice cultivation in river floodplains and malaria vectors in The Gambia

Variables Distance from landward edge P
  0–100 m
n = 140
200–500 m
n = 415
 
aDepth (cm) 9.0
(8.4–9.7)
10.7
(10.1–11.2)
0.001
aTurbidity (ntu) 107.9
(86.9–133.9)
129.0
(120.8–137.8)
ns
bpH 7.0
(6.8–7.3)
7.6
(7.5–7.7)
<0.001
aConductivity (mS/cm) 1.0
(0.9–1.2)
2.5
(2.3–2.7)
<0.001
aTemperature°C 30.2
(29.8–30.6)
28.6
(28.3–28.9)
<0.001
Oxygen content units (mg/L) 5.6
(5.2–6.1)
6.0
(5.8–6.2)
ns
Presence of moving water (%) 4.3% 99.0% <0.001
Height of rice (cm) 17.0
(12.9–21.1)
39.1
(35.5–42.7)
<0.001
Cow dung samples/site 132 33 <0.001
  N = 638 N = 802  
Total anopheline larvae
(proportion of occasions trapped)
349
(58/638)
26
(13/789)
<0.001
Anopheles gambiae s.l. 66
(19/638)
14
(9/802)
0.011
Anopheles gambiae s.s. 15
(3/638)
8
(2/802)
ns
Anopheles arabiensis 30
(6/638)
6
(2/802)
ns
Anopheles melas 21
(4/638)
0
(0/802)
0.038
Culicine larvae 423
(53/638)
19
(7/802)
<0.001
Other aquatic insects 912
(19/638)
532
(9/802)
<0.001
Mean no. invertebrate taxa, excluding mosquitoes 3.1
(2.6–3.6)
0.9
(0.8–1.0)
<0.001
Mean no. fish species/sample 0 1.19
(0.68–1.59)
 
  1. Values shown are means after the data were normalized a by log transformation (ln(x +1)), or b by squaring values. Figures in parenthesis represent 95% confidence intervals for abiotic variables and proportion of sites with specimens for biotic variables.