nstantaneous and historical temperature effects on a-pinene
Impact of mineral deposition on shrimp, Penaeusmonodon
in a high alkaline water
Author Details
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A.Gopalakrishnan
Centre
of Advanced Study in Marine Biology, AnnamalaiUniversity,
Parangipettai - 608 502, India
M.Rajkumar
Institute of Oceanology,
Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, P.R. China
Jun
Sun
(Corresponding
author)
Institute of Oceanology, Chinese
Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, P.R. China
e-mail: phytoplankton@163.com
GaryG.Martin
Department
of Biology, OccidentalCollege, Los
Angeles, California, USA 90041
A.Parida
M.S.
Swaminathan Research Foundation, Third Cross Street,
Institutional Area, Taramanai,
Chennai
- 600 113, India
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Publication Data
Paper received:
29
October 2009
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Revised
received:
23
March 2010
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Accepted:
20 April 2010
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Abstract
This study compares water
quality parameters, shrimp growth and mortality rates, and biomass at harvest
in two ponds of equal size, seeded with the same density (7 m-2)
of White Spot Syndrome Virus (WSSV) and MonodonBaculo Virus (MBV) negative post-larvae (PL)-20 of
shrimp, Penaeusmonodon
in the Vellar estuary of South India. The primary
difference between the ponds was the water source; one was filled from the
estuary and the second with water from bore wells with high alkalinity.
Temperature in both ponds was similar and reached 32oC after 185
days of culture. Dissolved oxygen (DO) levels were within the acceptable
range although levels in the alkaline pond were near the lower limit for the
last 90 days before harvest. Salinity levels were similar in both ponds,
above optimal levels, and increased over the 185 days. Alkalinity in the
estuarine water was typically < 50 ppm and again
200-320 ppm in the alkaline pond. In the alkaline
pond, beginning on the 75th day mineral
deposits was observed covering all parts of the shrimp including the eye and
the inner gill chambers, and by harvest, 42% of the shrimp showed this
coating. Elemental analysis identified the major constituents as calcium,
phosphorus and manganese. Survival rates in the estuarine-water-fed pond was
92% with a total pond biomass at harvest of 1.65 tons ha-1
compared to survival of 79% in the alkaline pond and a biomass at harvest of
1.020 tons ha-1. When well water must be used, its alkalinity
should be monitored and diluted with water from other sources.
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Key
words
Shrimp culture,Penaeusmonodon,
Alkaline pond, Mineral deposit