Determinación de densidad de siembra adecuada para la concha prieta anadara tuberculosa en el cantón El Guabo

This document contains the summary of the research developed in La Puntilla, in the Tendales town, El Guabo city. The investigation was about the determination of the right density of sowing for the ark shell (Anadara tuberculosa) in fatting yards in their natural environment, with different densiti...

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Váldodahkki: Aguilar Zambrano, Mayra (author)
Materiálatiipa: bachelorThesis
Giella:spa
Almmustuhtton: 2006
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Liŋkkat:http://repositorio.utmachala.edu.ec/handle/48000/1791
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Čoahkkáigeassu:This document contains the summary of the research developed in La Puntilla, in the Tendales town, El Guabo city. The investigation was about the determination of the right density of sowing for the ark shell (Anadara tuberculosa) in fatting yards in their natural environment, with different densities during six months. The objectives proposed for this research were: 1. To determine the optimal density of sowing for the Anadara tuberculosa crop. 2. To analyze the efficiency of the fatting yards. This research came up from the need of looking for new sea production alternatives, because the economical and environmental consequences that the shrimp sector’s crisis left a few years ago, that is, the appearance of the White Spot Syndrome Virus. This investigation started on November, 4th 2004, by getting a sample every 30 days, in which we got the weight in grams, the length, the height and the width of the shell in centimeters. We finished this activity on April, 3rd, 2005. The modules of the research consisted in 12 yards of one squared meter each one. These ones were built in the mangrove’ surrounding area, and were placed agree with the availability of the land. We worked with 4 different densities by squared meter; these were: 5, 10, 15 and 20 organisms, with 3 repetitions each one. Their beginning measures fluctuated between 26.31 and 36.04 mm of length; 18.52 and 27.84 mm of height; 13.12 and 20.97 mm of shell width, and a total weight that went from 3.90 to 13.50 gr. The yards were cleaned with a little brush in every sample (every 30 days), in order to avoid the accumulation of the sediment, which stops the free flow of plankton and detritus that are the food for these mollusks in their natural environment. We also considered the environmental parameters, which were taken in every sample. The average results we saw during the 6 months period are the following: a temperature of 25.1 ºC, pH of 7.6, dissolve water oxygen of 3.9 mg/lt, salinity of 28.7 ‰ and a turbid of 34.3 cm. Besides, we developed a qualitative analysis of the plancktonical organisms we found in the water, in which one we saw a variety of phytoplankton, among which we have: Coscinodiscus, Biddulphia, Nitzschia delicatisima, Nitzschia longisima, Chaetoceros, Tabellaria, Skeletonema, Thalasiotrix, Ceratium fucus, Silicoflagelado ditylum, Navicula sp., y Peridinium sp. We also saw Copepodos y Copepoditos between the zooplancton. The results of the weight increase were: 7.1479 gr/month; the augment of the length was: 4.0306 mm/month; the height was: 3.400 mm/month; and the width expand was: 3.4781 mm/month. With these results, we conclude that Anadara tuberculosa is a slow growth mollusks, that its raising is feasible if we use yards in its natural habitat, and that the crop density is not a limit on its growth.