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EN
The evaluation of water quality is commonly conducted by measuring physicochemical parameters. However, to enable identification of water quality changes of aquatic ecosystems, such as lakes, requires long time series data sampling. In this study, we performed water quality assessments by utilising the presence of potential harmful algae presence in Lake Ranu Grati, Indonesia. We conducted water sampling to evaluate 13 water quality parameters (in-situ and ex-situ) and identified the phytoplankton community structure of the lake at seven sampling sites from December 2018 to February 2019. To assess the water quality of the lake, we used two approaches. First, calculated the classical water quality index using the STORET method. Second, identified the potential harmful algae from the phytoplankton community structure of Lake Ranu Grati, and then determined the water quality factors related to its occurrence using canonical correspondence analysis. The results showed that water quality conditio of Lake Ranu Grati was optimum except for COD, BOD and ammonia. The STORET index also classified the seven sites in Lake Ranu Grati as lightly polluted and moderately polluted. Considering the presence of potentially harmful algae from the Cyanophyta and Euglenophyta divisions, it was suggested that Sites 6 and 7 were the most polluted areas of Lake Ranu Grati, which corresponded to the high concentration of COD and BOD. This finding indicates that agricultural and aquaculture activities around the lake need to be controlled to maintain the sustainability of the water quality condition of Lake Ranu Grati.
EN
Corn cobs and bagasse are materials used for making activated carbon that are easy to find. Additionally, they are agricultural waste that cannot be consumed. This study aims to analyze the potential of activated carbon from agricultural waste, namely corn cobs and bagasse, in reducing the levels of chromium heavy metal, and to analyze the dose of activated carbon from agricultural waste which is effective in reducing the chromium levels in the batik waste. The method used was experimental with a completely randomized factorial design. The doses of activated carbon used were 0.5, 1.5, and 2.5 g. Meanwhile, the contact times used were 30, 60, 90, 120, and 150 minutes. The results showed that the initial chromium content was 0.144 mg•L-1, and after given treatment it decreased to below 0.024 mg•L-1. The activated carbon from corn cobs and bagasse was able to reduce the chromium levels with the most effective dose of 2.5 g•L-1 and a contact time of 120 minutes. Meanwhile, the water quality parameters showed temperature stability (23–25°C) during the experimental period, while the pH increased to 9–11.
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.
EN
Surface water resource, such as river, is constantly contaminated by domestic and industrial pollutants. In order to properly manage the water resource, a composite index for water quality assessment, such as water quality index (WQI), has been designed to monitor and evaluate the properties of surface water. However, this index is quite subjective in terms of determination of relative weights. A principal component analysis (PCA) can be used to reduce the dimension and subjectivity of water quality variables. The purpose of this study was to implement the use of hybrid PCA and WQI methods to assess and monitor the water quality of the Bengawan Solo River, which is located in Java Island, Indonesia. The result suggested that COD, BOD, TSS, TDS, nitrate, nitrite, and ammonia were the main factors that determine water quality of the Bengawan Solo River. Furthermore, it was revealed that most samples from the river showed water quality status as slightly polluted. In addition to this, the seasonal variation of the PCWI values indicated a significant increase of water pollution in the Bengawan Solo River per year.
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 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.
EN
Whiteleg shrimp (Litopenaeus vannamei) farming is a major activity in the coastal areas of many tropical countries. To meet the demand in this market, the culture system has expanded using intensive technology, which has resulted in the emission of effluents that threaten the surrounding aquatic ecosystem. Therefore, proper aquaculture management is needed to ensure both economic and ecological benefits. This led to the emergence of eco-green aquaculture. Water quality monitoring is a critical part of aquaculture management and when performed regularly, it yields a large and complex dataset. In this study, the authors aimed to analyse the dynamics of water quality characteristics and the relationships between these variables in whiteleg shrimp ponds in a tropical eco-green aquaculture system from 2020 to 2022. Since the data includes nine parameters and is quite complex, the principal component analysis (PCA) approach was used. This method enables to identify the factors that determine water quality, which will help ensure effective and efficient aquaculture management. Consequently, the water quality variables in the studied area were reduced to five dimensions and salinity, ammonia, and pH were found to be the key factors responsible for the changes in water quality characteristics. Hence, these variables should be the focus of farming management systems.
EN
The East Java coast has biodiversity potential, including microalgae. Microalgae are primary producers for the aquatic ecosystem, whose distribution depends on water quality parameters and sub-habitat characteristics. The purpose of this study was to analyse and identify the microalgae, as well as environmental quality parameters based on sub-habitat characteristics in the northern part of the East Java coast, Indonesia. The research was conducted from March to June 2023. Sample sites were determined using purposive sampling techniques at nine sites located in Gresik, Lamongan, and Tuban coasts. Water samples were collected from various sub-habitats, including the water column, sediments, rocks, mangroves, artificial substrates, macroalgae, and water plants consisting of water hyacinth (Eichhornia crassipes) and Coontail (Ceratophyllum demersum). The obtained results depicted microalgae found were from Bacillariophyceae, Chlorophyceae, Chrysophyceae, Coscinodiscophyceae, Cyanophyceae, Dinophyceae, Trebouxiophyceae, and Zygnematophyceae. Bacillariophyceae dominated the community in all sites. The expected outcome of this study is to provide and complete the database of microalgae morphologically based on sub-habitat characteristics, particularly on the north coast of East Java, Indonesia.
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