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EN
The goal of this study was to examine and assess the stability of phytoplankton communities in connection to the different health status type of shrimp pond (healthy and diseased) in an intensive culture. The research was conducted in two ponds located in Probolinggo region, which had different health status until the eight week of harvest period. Several water quality variables and phytoplankton community composition were observed. Non-metric dimensional scaling and analysis of similarity were used to compare the phytoplankton community structure and water quality parameters in both ponds. In addition, the stability of phytoplankton community in these ponds was measured using species turnover rate, rate change of composition community, and community stability indices. The results showed that phytoplankton community structure and water quality factors between a diseased and healthy pond were not statistically significant. On the other hand, the phytoplankton community in the healthy pond was more stable than that of the diseased pond. Furthermore, ammonia and phosphate were found as the dominant factors affecting the phytoplankton community in the studied ponds.
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EN
Phycoremediation refers to the technology of using microalgae to reduce pollutants in the aquatic environment. The purpose of this study was to analyze the reduction of mercury heavy metal in the media by using several species of microalgae such as Spirulina maxima, Nannochloropsis oculata, Chlorella vulgaris, and Porphyridium cruentum. The algae were exposed to mercury during eight days of cultivation. A randomized design was set with three different concentrations of mercury, namely 1, 3, and 5 mg/dm3, with three replications for each concentration. The initial concentration of microalgae was set to 10 000 cells/cm3 for S. maxima and N. oculata, while the concentration for C. vulgaris and P. cruentum was set to 100 000 cells/cm3. The concentration of mercury was measured at the beginning (1st day), the middle (4th day), and the end of microalgae cultivation (8th day) by using the atomic absorption spectroscopy (AAS) tool. The result demonstrated a reduction of mercury concentration during the experiment in all experimental media, where the highest reduction was found at 1 mg/dm3 (p < 0.05). In conclusion, microalgae have their limited ability to absorb and adsorb heavy metals. Therefore, the utilization of low-concentration microalgae on reducing heavy metal such mercury is recommended and merits further investigation.
EN
Mangroves are a crucial ecosystem in coastal areas and serve a significant ecological function. However, this ecosystem is under the continuous pressure of anthropogenic activities which create toxic contaminants, such as heavy metals. The presence of marine ports and electric steam power plants next to Bee Jay Bakau Resort (BJBR) Mangrove Forest may worsen the heavy metal pollution, especially in the case of non-essential metals like lead (Pb). The vegetation in mangrove ecosystems can help store and trap this contaminant. Therefore, the objective of this study was to determine the potency of the Avicennia alba and Rhizopora mucronata mangrove species, which dominate the mangrove vegetation in BJBR Mangrove Forest, as Pb phytoremediation agents. The samples were taken from the sediment, roots, stems, and leaves of the mangrove trees. The results showed that the Pb found in the sediment of these species ranged from 10.323 to 11.071 ppm, while the Pb concentration in the mangrove parts was less than 1 ppm with the order roots > stems > leaves. Furthermore, the statistical analysis indicated that there were no statistically significant differences in the Pb values across sites and species. Moreover, the BCF, BAC, and TF in this study were less than 1, making the observed mangrove species unsuitable for phytoextraction or phytostabilization.
EN
This study aims to analyze the lipid, carbohydrate and protein content of Chlorella pyrenoidosa after being treated with the tofu wastewater. The method used in this study was an experimental method with 4 treatments and 3 replications. The treatment was performed by administering different concentrations of the tofu wastewater to the C. pyrenoidosa. The concentrations used were 10%, 15% and 20%. Determination of these concentrations was based on the preliminary test. The main parameters observed were the lipid, carbohydrate and protein content of C. pyrenoidosa and the supporting parameters were the growth rate, doubling time and characteristics of the tofu wastewater. The study was conducted for 8 days using the batch culture method. In the exponential phase, the microalgae were harvested and then their contents were analyzed. The data obtained were analyzed using MS Office Excel 2016. The highest content of lipid, carbohydrate and protein of C. pyrenoidosa was in the treatment of 20% tofu wastewater, reaching 1.56%; 28.92%; and 28.92%, respectively. Meanwhile, the highest growth rate and the smallest doubling time in the treatment of 20% tofu wastewater accounted for 0.8264 day-1 and 0.0349 hours-1. Moreover, the rates of BOD and TSS of the tofu wastewater at the end of the study decreased. It can be concluded that administering different concentrations of the tofu wastewater can affect the lipid, carbohydrate and protein content of C. pyrenoidosa. It was suggested that further research is needed to conduct semi-continuous cultivation of C. pyrenoidosa using a higher density so that the results obtained can be optimized.
EN
This research analysed the availability of phytoplankton and the growth rate of Vannamei shrimp in relation to water quality changes. The research was carried out in February-March 2021 for a half cycle of shrimp cultivation in two ponds of the Brackish Water Fish Culture Probolinggo Laboratory in Probolinggo, East Java, Indonesia. The research used a descriptive method and included a survey. Sampling was made every two weeks for two months. Nine parameters were measured and ten shrimps were taken for a specific growth rate (SGR) measurement once per sampling. Data were analysed using the principal component analysis (PCA) and canonical correspondence analysis (CCA). Secondary data of water quality were added for the PCA. The results show that the phytoplankton found in the first pond consisted of Chlorophyta, Chrysophyta, and Cyanophyta, whereas the phytoplankton in the other pond included Chlorophyta, Chrysophyta, Cyanophyta, and Dinophyta. The abundance of phytoplankton ranged from 12-80∙103 cell∙cm-3, which indicated eutrophic waters. The PCA demonstrated that pH, nitrate, and total organic matter (TOM) significantly influenced phytoplankton abundance in the pond. In addition, water quality parameters, such as temperature, transparency, salinity, nitrite and phosphate levels, were tolerable in both ponds for the growth of shrimps. However, the level of pH was lower than the aquaculture quality standard, whereas those of nitrate, ammonia, and TOM were higher. The growth rate of Vannamei shrimp increased by 0.76–7.34%∙day-1.
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