Navegando por Assunto "Carcinicultura"

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Acesso aberto (Open Access)
Acúmulo e fracionamento de fósforo nos sedimentos do estuário do rio Coreaú (Ceará) para avaliação do impacto da carcinicultura
(Universidade Federal do Pará, 2014-11-17) AQUINO, Rafael Fernando Oliveira; KAWAKAMI, Silvia Keiko; http://lattes.cnpq.br/5306256489815710; CORRÊA, José Augusto Martins; http://lattes.cnpq.br/6527800269860568
The shrimp culture (shrimp farms) is one of the activities of aquaculture widely employed in Brazilian estuaries and mangroves. The shrimps are fed with phosphate enriched compounds. Thus, the effluent produced by farms can accelerate the eutrophication process. An increase of shrimp farming has been seen in Coreaú River Estuary, state of Ceará, but data about environmental quality are scarce to allow monitoring of the region. The aim of the present research was to assess the contribution of the shrimp farms on phosphorus input to the Coreaú River Estuary. The main forms of phosphorus: bioavailable (P-Exch); bound to iron oxy-hydroxides (P-Fe), on the biogenic, autigênica carbonates and apatite (P-CFAP), on the detrital apatite (P-FAP) and organic phosphorus (P-Org) and as well as total organic carbon (%TOC) and chlorophyll-a were determined in samples of surface sediments and cores from the margins of the Coreaú River Estuary. The high concentrations of P-Total in surface sediments indicated the need for monitoring studies. The larger fraction was P-Fe, composing 30% of P-Total, approximately. These results indicate the ability of the iron oxy-hydroxides to immobilize or release phosphorus. The contribution of the farm’s effluents was evidenced by higher concentrations of P-Org in points adjacent to discharge areas. In sediment cores, the highest P-Total concentrations were found predominantly in fine sediments (silt and clay), with the P-Fe, P-CFAP and P-FAP fractions being the main contributors. The sedimentation rates and concentration increases of P-Total indicate the possible period of deforestation and starting or maximum activity of shrimp farms in the end of the 1980 and mid 1990, respectively. High phosphorus concentrations as well as %TOC and chlorophyll-a levels suggested a significant anthropogenic contribution, associated with a high potential for eutrophication.
Acesso aberto (Open Access)
Avaliação da qualidade da água e da sazonalidade no processo produtivo de Litopenaeus vannamei (Boone, 1931) no município de Curuçá–PA
(Universidade Federal do Pará, 2013-05-29) PALHETA, Glauber David Almeida; MELO, Nuno Filipe Alves Correia de; http://lattes.cnpq.br/4989238044542736; ROCHA, Rossineide Martins da; http://lattes.cnpq.br/4371300451793081
Shrimp production in Amazon has a potential to rise in the next years. Litopenaeus vannamei is a marine species which is starting to be better explored in Para State. This is due to water quality, more precisely to physical, chemical, hydrologic and sanitary water condition, and sediments. We can also mention that the seasonality of region may contribute to adequate condition for L. vannamei production. The accompaniment of water conditions are indispensable to understand how the seasonality could affect the shrimp production in Para State. The management in shrimp farm could be improved with inclusion of statistic in the data from shrimp farm and this technique maybe used to model the parameters during the cultivation and, consequently, improving the production and decreasing the cost. Therefore, the Thesis aimed to evaluate the influence of seasonality in water quality and shrimp growth. To those evaluations, the shrimp production in a commercial farm (Curuçá city, PA) was evaluate during the two cycle found in the region, and the first was from January to April of 2011 (rainy season) and the second was from July to November of 2012 (less rainy season). The farm had four tanks of one hectare of water surface and those thanks were used alternately in both cycles. In general, the seasonality found in Amazon altered the water quality in both cycles, but the shrimp cultivation was not affected. In addition, the production showed to be viable economically in both periods (rainy and less rainy season). There was correlation among rainfall and shrimp production.
Acesso aberto (Open Access)
A resiliênca dos manguezais do estuário do rio Ceará Mirim-RN às intervenções humanas.
(Universidade Federal do Pará, 2024-09-23) AQUINO, Ronaldo Darlan Gaspar; COHEN, Marcelo Cancela Lisboa; http://lattes.cnpq.br/8809787145146228
Mangroves are recognized for being extremely sensitive to changes in the physical and chemical environment and are widely used as indicators of changes in climate, sea level, and human interference. The study area comprises the mouth of the Ceará-Mirim/RN River, located on the coast of the state of Rio Grande do Norte (RN), in northeastern Brazil. This area has a history of mangrove deforestation for implementing shrimp farming. This study aims to analyze the mangrove dynamics from 1985 to 2020. The research uses orbital remote sensing and drone images to develop a spatial-temporal analysis. The data indicates that despite the expansion of aquaculture activity from 46 ha to 183.47 ha considering active and inactive tanks, there was an increase in mangrove areas from 351 to 489 ha. Over the 35 years, aquaculture activity has mainly occupied flooded fields and apicum regions and occasionally some areas have been converted from mangrove areas. However, the expansion in mangrove areas was mostly due to the abandonment of aquaculture, which before 1985 suppressed mangroves to construct ponds. Despite severe anthropogenic interference in this delicate ecosystem, these forests have shown great resilience by recolonizing their tidal flats.