Table 1 Basic characteristics of pond water and sediment quality during an intensive whiteleg shrimp culture cycle
Pond operation | Parameters | Culture stage | Min | Max | Mean | SD |
|---|---|---|---|---|---|---|
Water | Temperature (°C) | Pond preparation | 30.6 | 30.8 | 30.7 | 0.1 |
Feeding (1 month after stocking) | 29.7 | 30.6 | 30.1 | 0.4 | ||
Feeding (2 months after stocking) | 29.7 | 31.6 | 30.4 | 0.7 | ||
Harvesting | 20.6 | 21.5 | 21.0 | 0.3 | ||
pH | Pond preparation | 7.3 | 8.5 | – | – | |
Feeding (1 month after stocking) | 7.9 | 8.6 | – | – | ||
Feeding (2 months after stocking) | 8.6 | 8.8 | – | – | ||
Harvesting | 9.0 | 9.1 | – | – | ||
DO (mg L− 1) | Pond preparation | – | – | – | – | |
Feeding (1 month after stocking) | – | – | – | – | ||
Feeding (2 months after stocking) | 6.0 | 7.6 | 6.5 | 0.6 | ||
Harvesting | 9.6 | 9.9 | 9.7 | 0.1 | ||
Salinity (ppt) | Pond preparation | 0.6 | 0.6 | 0.6 | 0.0 | |
Feeding (1 month after stocking) | 0.5 | 0.5 | 0.5 | 0.0 | ||
Feeding (2 months after stocking) | 0.5 | 0.5 | 0.5 | 0.0 | ||
Harvesting | 0.6 | 0.6 | 0.6 | 0.0 | ||
TDS (mg L−1) | Pond preparation | 654 | 656 | 655 | 0.7 | |
Feeding (1 month after stocking) | 552 | 560 | 555 | 3.3 | ||
Feeding (2 months after stocking) | 528 | 531 | 529 | 1.1 | ||
Harvesting | 612 | 614 | 613 | 0.8 | ||
EC (μScm−1) | Pond preparation | 1308 | 1312 | 1310 | 1.5 | |
Feeding (1 month after stocking) | 1103 | 1120 | 1110 | 6.8 | ||
Feeding (2 months after stocking) | 1057 | 1061 | 1059 | 1.6 | ||
Harvesting | 1224 | 1227 | 1226 | 1.1 | ||
Sediment | OM (g kg−1) | Pond preparation | 9.1 | 10.2 | 9.6 | 0.5 |
Feeding (1 month after stocking) | 10.8 | 11.2 | 11.1 | 0.2 | ||
Feeding (2 months after stocking) | 10.3 | 12.3 | 11.1 | 1.0 | ||
Harvesting | 11.1 | 12.7 | 12.7 | 0.9 | ||
pH | Pond preparation | 6.8 | 7.6 | – | – | |
Feeding (1 month after stocking) | 6.8 | 7.6 | – | – | ||
Feeding (2 months after stocking) | 6.8 | 7.6 | – | – | ||
Harvesting | 7.4 | 8.0 | – | – |