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1.
Article | IMSEAR | ID: sea-217198

ABSTRACT

Anthropogenic activities around the sea ports are capable of causing changes on the physicochemical and microbiological quality of water bodies along the port terminals. Such activities can cause an ecological imbalance in the water quality /ecosystem resulting in extinction of aquatic resources. The aim of this study therefore was to investigate the physicochemical and microbiological quality of surface water along the busy port terminals. Surface water samples were collected from Onne port terminal using sterile containers. The samples were collected during the wet and dry seasons between January to June 2021. The sterile bottles were filled with surface water samples and transported in an ice packed container to the Department of Microbiology Laboratory of the Rivers State University for analyses using standard analytical methods. Statistical analyses were carried out using ANOVA and All pairs tukey-kramer. Results of the physicochemical parameters showed that temperature, total dissolved solids, total suspended solids, nitrate and heavy metals were significantly higher during the dry season than the wet season at P ? 0.05 levels of significance. Seasonal variation with respect to microbial counts shows that Total Heterotrophic Bacteria, Total Heterotrophic Fungi, Total coliforms and Faecal coliforms had a mean value of 3.9±1.77 x 106; 0.8 ±0.05 x 104 ; 7.4 ±1.3 x 104 and 3.6 ±0.17 x 104 colony forming unit per millilitre respectively for wet season while the dry season had 1.6±0.77 x 106 , 0.5 ±0.01 x 104 , 4.6 ±0.17 x 104 and 2.7 ±1.03 x 104 cfu/ml respectively. In this study, the predominant bacterial isolates belonged to the genera of Vibrio, Pseudomonas, Klebsiella, Bacillus, Shigella, Staphylococcus, Salmonella, Proteus, Bacillus and Escherichia. coli. The results of physicochemical and microbiological characteristics including the heavy metals, were detected at concentrations on or below detection limits.. It is therefore suggested that relevant environmental regulatory bodies should maintain regular check to ensure that appropriate standards are maintained around seaports due to beehive of activities.

2.
Rev. biol. trop ; 64(1): 105-115, ene.-mar. 2016. tab, ilus
Article in Spanish | LILACS | ID: biblio-843264

ABSTRACT

ResumenLas diatomeas del bentos son el componente más estudiado del perifiton en los ríos de Costa Rica, sin embargo aún queda mucho por conocer sobre su ecología. Por eso en el presente estudio se analizó el perifiton en seis diferentes sitios en la cuenca medio del Río Sarapiquí en el 2010, 2011 y 2012. En cada uno de los muestreos se realizó el conteo de 400 frústulas, de las cuales se obtuvo la abundancia relativa de las especies: Achnanthidium exiguum, Coconneis placentula, Cymbella tumida, Luticola goeppertiana, Luticola ventricosa, Navicula symmetrica, Nitzchia clausii, Nupela praecipua, Reimeria sinuata y Synedra goulardi. Esta información fue relacionada con los datos físico químicos (oxígeno disuelto, temperatura, conductividad, total de sedimentos en suspensión, turbidez, pH y alcalinidad) medidos en cada uno de los sitios. Con el propósito de observar las relaciones entre los diferentes sitios dentro de la cuenca, se utilizó un análisis de correspondencia canónica (ACC), lo que permitió distinguir tres sectores de acuerdo a la altitud. Estos sectores se diferencian en el tipo de sustrato, cobertura riparia vegetal y parámetros físico-químicos, lo que propicia diferencias en la composición de especies de diatomeas entre ellos. Se obtuvieron los valores óptimos calculados y tolerancia calculada para cada una de las especies. Los resultados obtenidos indican que las especies: A. exiguum, R. sinuata,L. ventricosa y C. tumida, dominan en aguas limpias, oxigenadas y baja temperatura. Las especies N. praecipua, S. goulardi, C. placentula, L. goeppertiana, N. clausii y N. symmetrica se encuentran en aguas cálidas, alta turbidez y poco oxigenadas. Las especies A. exiguum, R. sinuata, prevalecen en sitios con agua alcalina y baja conductividad y las especies N. symmetrica, C. tumida y L. ventricosa presentan una relación positiva con la conductividad y el pH de las aguas. Las especies estudiadas mostraron buenos indicios de su valor como indicadores de calidad del agua, sin embargo, debido a diferencias de interpretación por varios autores, es necesario realizar más estudios en otras cuencas hidrográficas en el país.


Abstract The tolerance of ten diatom species (Bacillariophyceae) to water's physico-chemical factors in the Sarapiqui River, Costa Rica. Benthic diatoms are the periphyton component most studied in Costa Rican rivers, yet there is still much to be known about their ecology. This study aims to contribute to this knowledge. Periphyton samples from six locations along the middle reach of Sarapiquí river and some of its tributaries were taken and analyzed from 2010 to 2012. A total count of 400 frustules was performed in each sample to obtain relative abundances of each species. Ten species, which were easily recognized at the light microscope, were analyzed here: Achnanthidium exiguum, Coconneis placentula, Cymbella tumida, Luticola goeppertiana, Luticola ventricosa, Navicula symmetrica, Nitzchia clausii, Nupela praecipua, Reimeria sinuata and Synedra goulardi. Their abundance was related to physico chemical data at each site for every sampling date (dissolved oxygen, temperature, conductivity, total suspended solids, turbidity, pH and alkalinity) with a canonical correspondence analysis (CCA) that allowed distinguishing three sectors along the river according to altitude. These sectors differed by substrate, riparian vegetation cover, and physic-chemical parameters, all of which resulted in differences in diatom species composition among them. Optimum values and tolerances form each environmental parameter were calculated for each species. Our results showed that A. exiguum, R. sinuata,L. ventricosa and C. tumida, were dominant in clean and well oxygenated waters with low temperatures. The species N. praecipua, S. goulardi, C. placentula, L. goeppertiana, N. clausii and N. symmetrica inhabited warm waters with high turbidity and low oxygen. The species A. exiguum, R. sinuata were dominant in sites with low alkalinity and conductivity, whereas species like N. symmetrica, C. tumida and L. ventricosa showed a positive relationship with conductivity and pH. The studied species showed good characteristics of their value as water quality indicators, yet due to different interpretations by several authors, it is necessary to perform further studies at more river basins in the country. Rev. Biol. Trop. 64 (1): 105-115. Epub 2016 March 01.


Subject(s)
Water/chemistry , Environmental Monitoring/methods , Diatoms/physiology , Rivers/chemistry , Diatoms/classification , Costa Rica
3.
Braz. arch. biol. technol ; 56(5): 875-884, Sept.-Oct. 2013. graf, mapas, tab
Article in English | LILACS | ID: lil-689816

ABSTRACT

The aim of this work was to study the physicochemical parameters of water quality collected from 12 sampling stations from Topputhurai to Muthupet in Vedaranyam located on the southeast coast of India from January to December 2008. Results showed that the DO and nutrients were the maximum in the Bay of Bengal during the monsoon period. High concentration of the nutrients in summer season was obtained near the Muthupet mangroves compared to the Palk Strait, which showed that this acted as a source of nutrients to the adjacent coastal waters. Low concentrations of the nutrients observed in the monsoon could be attributed to the terrestrial runoff from Muthupet lagoon. The physicochemical characteristics of coastal waters between the Point Calimere and Muthupet could be used as a baseline data for the monitoring, conservation and management of Point Calimere Wildlife and Bird sanctuary, Great Vedaranyam swamp and Muthupet mangrove ecosystem.

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