oxygen and sediments become anoxic below the surface. found
that the density of aerobic and anaerobic bacteria in the pond bottom soil is two to four
orders of magnitude higher than the density of these groups in the water column. found that bacterial count and productivity in shrimp pond sediments were
two orders of magnitude greater than in the water column. found that
the bacterial count in the sediments of shrimp ponds fertilized with chicken manure was
4 1013 bacteria m 2
, which was two to three orders of magnitude higher than in the
water column. Allen et al. (1995) determined the number of bacteria in shrimp ponds
sediments during 71 rearing days, and found that the bacterial count increased with time.
The average bacteria count was 8.39 F 0.35 108 cm 3
, ranging from 4.03 to
12.36 108 cells cm 3
. reported a bacteria count of 15.5 109
cells/g in the center of shrimp ponds where sludge accumulated and 8.1 109 cells/g at
the periphery of the pond. In this study, it was found that the bacteria count increased
with the nutrient concentrations and with smaller sediment grain size