Nutrient and Particulate Matter Sedimentation Rates in Penaeus Vannamei Cultures With Different Stocking Densities

Abstract This study evaluated the sedimentation rates of nutrients and particulate matter from monocultures of Pacific white shrimp, Penaeus vannamei, with different stocking densities in a semi-arid tropical region. The crops analyzed were C6: initial density of 6 shrimp.m⁻ ²; C20: 20 shrimp.m⁻ ²; and C50: 50 shrimp.m⁻ ². Two collections of sedimented material were conducted with the aid of sedimentation chambers, which took place in the period before cultivation (BC) and the other, at the end of cultivation (EC). The sedimentation rates of particulate matter and organic material in C6 and C50 in the EC period were significantly higher than values in the BC. The sedimentation rates of inorganic matter were significantly higher at the end of the three cultivations, contrary to what was observed for nitrogen and total phosphorus. C50 – EC had higher values of particulate matter, total phosphorus, organic and inorganic matter. We can conclude that although the cultivation time of C50 (64 days) was shorter than that of C6 (80) and C20 (99 days), it presented the highest values regarding sedimentation rates, possibly due to the high supply of feed in the cultivation of higher stocking density and, consequently, greater production of excrement and feed waste.