Three independent studies were conducted to quantify ultimate biochemical oxygen demand (UBOD) and the
corresponding decomposition rate constant for production pond (average 21.5 ha each) waters and effluents
on six semi-intensively managed marine shrimp (Litopenaeus vannamei) farms in Honduras. Samples were
collected during the rainy season in studies 1–3 and during the dry season only in Study 1. Pond water
samples were collected during the culture period and/or at harvest. The dry season 30-d biochemical oxygen
demand (BOD30) of pond waters across all farms was 26% lower and UBOD was 54% lower, but the
decomposition rate constant was more than twice as great as during the rainy season. During the dry season,
biochemical oxygen demand was nearly completely expressed after 30 d of incubation whereas during the
rainy season BOD was about 65% expressed after 31 d of incubation and the correlation between BOD31 and
UBOD was less strong compared to the dry season. Water quality variables were correlated with measures of
BOD during rainy and dry seasons, but only the correlation between chlorophyll a and BOD measures was
predictive. In studies 2 and 3, BOD after 88–94 d of incubation was expressed almost completely and
corresponded closely with computed UBOD. No significant differences in UBOD were detected in pond
samples taken after 30, 61, or 71 (harvest) d of grow out in study 3. Mean decomposition rate constant ranged
from 0.054 to 0.071 d−1 in studies 1–3 (rainy season), compared to 0.123 d−1 in Study 1 (dry season).
Published by Elsevier B.V.
Three independent studies were conducted to quantify ultimate biochemical oxygen demand (UBOD) and thecorresponding decomposition rate constant for production pond (average 21.5 ha each) waters and effluentson six semi-intensively managed marine shrimp (Litopenaeus vannamei) farms in Honduras. Samples werecollected during the rainy season in studies 1–3 and during the dry season only in Study 1. Pond watersamples were collected during the culture period and/or at harvest. The dry season 30-d biochemical oxygendemand (BOD30) of pond waters across all farms was 26% lower and UBOD was 54% lower, but thedecomposition rate constant was more than twice as great as during the rainy season. During the dry season,biochemical oxygen demand was nearly completely expressed after 30 d of incubation whereas during therainy season BOD was about 65% expressed after 31 d of incubation and the correlation between BOD31 andUBOD was less strong compared to the dry season. Water quality variables were correlated with measures ofBOD during rainy and dry seasons, but only the correlation between chlorophyll a and BOD measures waspredictive. In studies 2 and 3, BOD after 88–94 d of incubation was expressed almost completely andcorresponded closely with computed UBOD. No significant differences in UBOD were detected in pondsamples taken after 30, 61, or 71 (harvest) d of grow out in study 3. Mean decomposition rate constant rangedfrom 0.054 to 0.071 d−1 in studies 1–3 (rainy season), compared to 0.123 d−1 in Study 1 (dry season).Published by Elsevier B.V.
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