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