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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
Lead (Pb) is a non-essential heavy metal found as an inorganic pollutant in the water, sediment, and mangrove plant tissue in Wonorejo River Estuary. Several studies showed that its concentration exceeds the quality standard stipulated in the Indonesian Government Regulation Number 22 of 2021 and the EPA sediment quality. Moreover, the phytoremediation of Pb through mangroves Avicennia alba, Rhizophora stylosa, Sonneratia caseolaris, and Avicennia marina at Wonorejo River Estuary was investigated. It was discovered that the environmental factors such as temperature, pH, and salinity as well as bioconcentration factor (BCF) and translocation factor (TF) values are different for each species. The dynamics of the Pb phytoremediation system were also modeled using Vensim PLE x64 software to determine the effect of environmental factors such as temperature, pH, salinity, BOD and COD, as well as Pb concentration on the ability of mangroves to accumulate and translocate Pb. The results showed that a behavioral mechanism pattern was formed based on the relationship between the environmental factors, Pb concentration, and the phytoremediation ability of the mangroves with time. This pattern affected the root and leaf BCF values of each mangrove. Furthermore, the validation test showed that the model is structurally valid and has MAPE values for the Pb phytoremediation model with S. caseolaris and R. stylosa having <30% while Avicennia marina and A. alba had <50%. Therefore, the model was categorized as fairly good with a valid forecast. The system dynamics predicted that the highest concentrations of Pb in water, roots, and stems in 2041 were in R. stylose at 1,329,110 mg/L, 2,054,110 mg/kg, and 3,393,950 mg/kg, respectively. The highest accumulation value in plant tissue was dominated by mangrove species of R. stylose. In conclusion, the environmental parameter values at habitat of R. stylose were in good condition for the growth of the mangroves compared with other species of mangrove.
EN
Lead (Pb) is a heavy metal often discovered to be polluting the water areas. One of the efforts made to overcome the heavy metal pollution in estuaries was phytoremediation technique using mangroves. The Wonorejo River was one of the rivers that received industrial waste loads. There were various types of mangrove plant species at the estuary of the Wonorejo River. The location of this research was divided into 3 monitoring stations (A, B, C). Station A was directly adjacent to the estuary, as location C was farther away and very close to the sea. However, station B was located between location A and B. This study aimed to determine the ability of mangrove in remediating and illustrating the distribution of Pb, at the Wonorejo River estuary. Moreover, it also aimed to determine the values of Bioconcentration (BCF) and Translocation (TF) Factors in the ability of Avicennia alba, Avicennia marina, Sonneratia caseolaris, Avicennia lanata, and Rhizophora stylosa to accumulate Pb. The samples were the roots, stems, and leaves of mangroves, with the water and sediment at the Wonorejo estuary, as all solid materials were also extracted. The samples were analyzed for heavy metal concentration, using an atomic absorption spectrophotometer (AAS). The results showed that the highest average Pb concentration for waters and sediments was obtained at station C and A, with values of 0.069 mg/L and 4.22 mg/kg, respectively. It was further observed that the Pb concentration in the water was lower than in sediment, indicating that the metal was accumulated in the sediments. On the basis of the BCF value, the most effective mangrove involved in the accumulation of Pb was A. alba. The highest values of TF for both root to stems and to leaves in the accumulation of Pb was also discovered in A. lanata and A. alba mangroves, respectively. On the basis of the Pb distribution mapping, the concentration of the metal was shown to increased, as the research location moved further away from the estuary. Conclusively, each type of mangrove had different ability to accumulate and translocate Pb in its body, with the potential of using those plants as phytoremediaton agents for the metal.
EN
The heavy metal pollution in seawater and sediment can damage mangrove ecosystems and accumulate in mudskipper (Periophthalmus spp.) that lives in mangrove forests. The accumulation of heavy metal in mudskipper can affect the structure of its gill tissue, liver, and muscles. This research aims at (1) analyzing the levels of lead, cadmium and cuprum heavy metals in mudskipper, sediment, and seawater and (2) analyzing the damage to the gill, liver, and muscle tissue of mudskipper due to the exposure to heavy metals. The mudskipper samples were collected from the mangrove forests of Poka, Waai, and Rutong from May to June in 2019. The heavy metal analysis was conducted using the AAS method, while the gill, liver and muscle tissue staining was carried out with the HE (Hematoxylin Eosin) staining method with 40x magnification. The data were analyzed using descriptive analysis and correlational analysis. The results of the analysis showed that based on the mangrove locations, the order of Pb and Cu accumulation in mudskipper was Rutong> Poka> Waai; while the order of the Cd accumulation was Rutong> Waai> Poka. The changes in the gill tissue structure due to the exposure to heavy metals were in the form of teleangiectasia, secondary lamellar edema, hyperplasia, epithelial desquamation, clubbing, and primary lamellar edema. The changes in the liver tissue structure due to the exposure to heavy metals involved hemorrhage and fat degeneration. The changes in the muscle tissue structure due to the exposure to heavy metals include changes in muscle fibers, edema, and necrosis. The highest accumulation of Pb and Cd was found in gills and muscles from seawater, while low level of heavy metal Cu was found in the liver.
EN
The supply of clean water is a major environmental problem in some areas, which is possibly handled through the biodesalination technologies, a concept that involves separating the salt content, and reducing salinity, using bacteria and plants. This research therefore applied Avicennia marina (AM) and Rhizophora mucronata (RM) mangroves, in addition to Vibrio alginolyticus, in 12 reactor reed bed systems arranged in series (AM-RM) to attain a continuous flow. The evaluated salinity level was 20‰ and 25‰, obtained using artificial saline water. Meanwhile, the reed bed system, measuring 0.14 m3 (0.7×0.5×0.4 m), comprises a filter layer component, which consists of sand and gravel, with a diameter of 1 cm and 2 cm. This investigation was performed for 18 days, and samples were collected every 2 days, and the main parameters of salinity, Na, Cl and the potassium ion concentration, electric conductivity and Colony Forming Unit (CFU), as well as the supporting parameters, including pH and temperature, were evaluated. The results showed a water discharge rate of 18 mL/min, and the addition of Vibrio alginolyticus, produced the best salinity level (90%) on day 6 of operation. The outcome of the initial 25‰ sample value, measured as 20.09‰ at the inlet, was reduced to 1.99‰ at the outlet, after treating with Rhizophora mucronata. This was within the range for brackish water, and the calculations using the final salinity values showed a Cl-content of 1129.47 mg/L, while the best conductivity value was 3,485 mS/cm. In addition, the highest selective media CFU was Log 5.6, observed in the Avicennia marina 25‰ reactor, to which Vibrio alginolyticus was added. The supporting parameters of temperature and pH measured 30°C and a range of 6–8, respectively. Therefore, the removal of salt from brackish water using the mangrove operation is assumed to continuously produce low salinity levels.
EN
The current method of seawater bio-desalination can effectively provide freshwater. This method works by separating the salt contained in water into clean water with a lower salinity. In this study, the researchers conducted an experiment of the bio-desalination method by combining mangrove plant and Vibrio alginolyticus bacteria as well as the presence of a filter layer component composed of sand and gravel in red beed system reactor. The concept of phytotechnology was to utilize plants as environmental technology capable of solving environmental problems. In contrast, the term phytoremediation was used to denote the process of plants absorb, take, change and release contaminants from one medium to another. The purpose of this study was to determine the reduction of salinity on the mangrove plant Rhizophora mucronata (Rm) and Avicennia marina (Am) with the addition of Vibrio alginolyticus (Va) bacteria in the bio-desalination process using a reed bed system. This study combines plants and bacteria for artificial saline desalination processes. The compounds contained in plants are absorbed in the form of cations or anions, while the addition of the bacteria was carried out to support the process of salt absorption in plants. The results of this study indicated a percentage of salinity decreasing up to the last day of experiment. The results showed the percentage of salinity removal at the last day reaching 49.16%, and 40.58% in reed bed reactor with Avecennia marina and Vibrio alginolyticus of 15‰ and 25‰, respectively. Meanwhile, the percentage of salinity using Rhizophora mucronata showed 64.68% and 40.18% in in reed bed reactor with Rhizophora mucronata and Vibrio alginolyticus of 15‰ and 25‰, respectively. The removal of salinity also occured in the control reactor, containing only reed bed system without plant, reaching 57.36% and 58.41% in initial salinity of 15‰ and 25‰. All treatment reactors exhibited high salinity removal. It showed that the all concentrations of salinity were below 4‰ at Day 2 of reactor operation. It suggested that the process of desalination occurred in the entire reactor treatment. In conclusion, the reed bed system reactor can be used to treat saline water but the process of absorption of salts with mangrove plant and addition of Vibrio alginolyticus can be more stable.
EN
The phytotechnology concept that is applied for a bio-desalination reactor become a new desalination technology. The desalination technology can be called as bio-desalination technology to remove ions of Na+ and Cl- in brackish or saline water using mangrove plant. Before the mangrove plants were used in bio-desalination technology, the preliminary phytotoxicity test was conducted. The purpose was to determine the salinity concentration at which the mangrove species of Rhizophora mucronata can survive. The preliminary phytotoxicty test was carried out using a plastic reactor that was designed as a reed bed system. The reactors filled with gravel, sand, and artificial saline water. The variation of the NaCl concentrations were 0 mg/L as control, 10,000; 20,000; 30,000; 40,000, and 50,000 mg/L. The physical observation of the survival condition of Rhizophora mucronata was carried out during the preliminary test for 7 days. The analysis of Scanning Electron Microscopy (SEM) on Rhizophora mucronata was conducted at the end of exposure. The results showed that Rhizophora mucronata could not survive at the concentrations of 40,000 and 50,000 mg/L. Rhizophora mucronata changed the color of the leaves to brown and the stems become softer. Multiple cell damage and the decreasing trend of sodium and chloride amounts occured on roots and stems at the salinity concentration of 50,000 mg/L. In conclusion, the high of salinity concentration (> 30,000 mg/L) can be toxic to Rhizophora mucronata.
EN
Spatial variability in the population density of meiofauna and the assemblage of free-living marine nematodes was studied at 20 mangrove sites located along the Saudi Arabian coast of the Red Sea. The total abundance of meiofauna varied between the locations and ranged from 119 to 1380 ind. 10 cm-2. A total of seven main taxa were recorded. Nematodes dominated (64.3%) in all sediment samples. They were followed by harpacticoid copepods (13.2%) and polychaetes (12.9%) with significant differences in their density between the locations surveyed (p < 0.001). The Pearson correlation analysis showed significant positive correlations between the sand fraction and nematodes, harpacticoid copepods and turbellarians. Twenty-five genera of free-living nematodes belonging to 15 families were recorded in the study area. Microlaimidae were the most abundant family, while Xyalidae, Desomodridae and Chromidoridae were the most diverse families. Microlaimus, Halalaimus and Terschellingia were the most frequent genera. ANOSIM values obtained for the distribution of different nematode genera in various habitats showed no significant differences. Feeding types of different nematode genera were also documented and the epistrate feeders along with the deposit feeders were found to be the common feeding types in the present study.
EN
Mangroves play an integral role as a metal accumulator in tropical and subtropical marine ecosystems. Twenty-one sets of sediment samples and portions of mangroves were collected along the Saudi Arabian coast of the Red Sea to assess the accumulation and ecological risks of heavy metals. Results showed that the following mean concentrations of heavy metals in sediments: Cr (46.14 μg g−1 ± 18.48) > Cu (22.87 μg g−1 ± 13.60) > Ni (21.11 μg g−1 ± 3.2) > Pb (3.82 μg g−1 ± 2.46) > Cd (0.75 μg g−1 ± 0.87). The maximum concentrations of the studied metals were above the threshold effect level, indicating a limited impact on the respective ecosystems. The maximum concentration of Cd exceeded its toxic effect threshold, revealing a harmful risk to biota in the sediments. Based on metallo-phytoremedation, biological concentration factors were >1, suggesting that Avicennia marina can accumulate heavy metals, especially Cr and Pb. The translocation factor was above the known worldwide average. The geo-accumulation index revealed that sediments in mangrove areas ranged from moderately to heavily contaminated with Cd at Al-Haridhah and moderately contaminated at South Jeddah, Rabigh, Duba, and the wastewater treatment station near Jazan. The ecological risk index revealed that Cd could pose a relatively very high risk to the mangrove ecosystem. The present study emphasized the possibility of establishing a framework for the management of the coastal aquatic ecosystems along the Red Sea coast of Saudi Arabia.
EN
Root exudates were obtained from three mangrove species, viz. Bruguiera gymnorrhiza, Excoecaria agallocha, and Heritiera fomes. Spot tests revealed the presence of, presumably, phenolic compounds in the exudates. Paper chromatography revealed two spots each for B. gymnorrhiza and H. fomes and a single spot for E. agallocha. GC-MS analysis suggested the presence of aminopyrine, palmitic acid, stearic acid, di- n -propyl ether, and 2,5-anhydrogluconic acid in B. gymnorrhiza exudates, aminopyrine and palmitic acid in E. agallocha exudates, and aminopyrine, palmitic acid, and 2,5-anhydrogluconic acid in H. fomes exudates.
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