Analysis of Total Organic Matter, Total Nitrogen, and Total Phosphorus in the Estuary Waters of Maros as a Source of Brackish Water for Fish Ponds Aquaculture

Indonesia is a tropical area with high rainfall, the area on land is connected by around 472 large and small rivers that flow into the sea. The estuary area is the meeting area of ??rivers or fresh water streams with the ocean. Transportation of organic matter, minerals and sediments from upstream to the estuary and from the sea containing minerals, hence estuarine waters are more fertile than other areas. In addition, estuary areas are important habitats for several types of marine and freshwater organisms to fulfill their life cycles, which are used as spawning, foraging, and nursery grounds. This study aimed to determine the total organic contents, total Nitrogen, and Phosphorus in the estuary waters of Maros as a source of brackish water for fish pond aquaculture in Maros Regency. The research was conducted in the estuary waters of Maros for three months from September to November 2020. Sampling was conducted four times with an interval of once every 15 days. Sampling was carried out at five stations based on water movements to the estuary, station A was located at the seawater, station B was located in the pond wastewater locations, station C was water sources from residential waste, station D was located in the river, and station E was the estuarine water. The results showed that the dominant water quality parameters affecting estuarine water quality were salinity, total organic matter, nitrogen content, either in the form of ammonia, nitrate, or nitrite, and phosphorus content, especially phosphate. Water entering the estuary has an impact on high concentrations of total organic matter, increased concentrations of Total N, and phosphorus. The results of water quality analysis in estuaries showed that salinity, organic matter, ammonia, nitrite and nitrate, and phosphate exceed the standard threshold for water quality standards for fish pond aquaculture. Thus, the waters of the Maros estuary are not suitable for aquaculture, especially for the 5 observed stations (A, B, C, D and E).

Analysis of bacterial diversity associated with polyketide synthase (PKS) gene in brackish metagenome of TsoKar Lake of Ladakh, India

Aim: To explore bacterial diversity associated to polyketide synthase (PKS) genes in the TsoKar brackish metagenome.Methodology: The metagenomic DNA of TsoKar water and sediment samples were isolated and amplified using pks specific degenerate primers. PCR amplified products were analysed using Ion Torrent PGM platform and revealed a total of 2,11,030 reads with 534 contigs and 55% of G+C content. The results of BLASTx was further analyzed for species diversity using MEGAN5 software. Results: Halomonas was found to be the dominant phyla followed by Cyanobium, Acinetobacter and Burkholderia, respectively, along with majority of uncultured microorganisms present in TsoKar metagenome. Since TsoKar is a brackish water lake, and brackish aquatic ecosystems are a major hub of diverse microbes was also revealed in this study. TsoKar metagenomic sequence with accession number SRR8381943 was deposited in SRA database. Interpretation: TsoKar Lake is considered as one of the most important biosphere reserves. The results of this study confirm that this unique niche harbors good bacterial diversity associated with polyketide synthase genes, which justifies the idea of bioprospecting such niches for the discovery of novel metabolites like antimicrobial compounds using next-generation sequencing approach

Bioaccumulation of heavy metal lead (Pb) in different tissues of brackish water fish Mugil cephalus (Linnaeus, 1758)

This study was performed to determine the heavy metal accumulation concentrations in different tissues ofthe selected brackish water fish Mugil cephalus. The fishes were exposed to sub-lethal concentrations of leadacetate (Pb (C2H3O2)2) for 96 hour, and LC50 value was found to be 18.7 ppm. The one-tenth of (1/10) LC50(1.89 ppm) value was selected as a lower sub-lethal concentration for the exposure period of 30 days. Theorgans of fish, namely, gills, liver, and muscle were carefully separated through the dissection from fish forthe determination of heavy metal using Absorption Spectrophotometer (Perkin Elmer Analyst-400, USA). Theresults reveal that the low concentration of lead (1.89 ppm) exhibits a maximum level of accumulation in theliver (0.746 ± 0.0033 μg/g), gills (0.672 ± 0.0069 μg/g), and muscle (0.254 ± 0.0052 μg/g) tissues of 30 daysexposed. The result of the present investigation also reveals that the time-dependent lead accumulation indifferent tissues of fish M. cephalus exposed to different sub-lethal concentration of the lead. These findingsextend for future studies on the evaluation of lead accumulation tendency in relation to the eco-toxicologicalobservations for heavy metals risk assessment.

Eficiência de um sistema piloto de dessalinização de água salobra / Efficiency of a brackish water desalination pilot system

RESUMO Com a escassez da disponibilidade de água doce e o aumento da demanda de água no mundo e no Brasil, uma das alternativas são os sistemas de dessalinização de água, que removem os sais das águas salobra ou salgada. Este estudo teve como objetivo avaliar a eficiência de um sistema piloto de dessalinização de água salobra a qual foi obtida a partir da mistura de águas do mar e de rio até atingir concentração de sólidos dissolvidos totais (SDT) de 1.500 mg.L-1. O sistema piloto de dessalinização, com capacidade de 1,0 m3.h-1, é composto de ultrafiltração (UF) e abrandamento como pré-tratamento à osmose reversa (OR). Foram realizadas análises de qualidade da água na entrada e saída das unidades de tratamento relativas a SDT, condutividade elétrica, turbidez, pH, cor aparente, alcalinidade, dureza total, cálcio, magnésio, cloreto, sulfato e temperatura. Foram avaliadas a pressão osmótica, o fluxo de filtração e a taxa de recuperação de água no sistema de OR. Com os resultados obtidos, conclui-se que a eficiência de remoção de SDT e condutividade foi de 99%. A UF foi eficiente na remoção de turbidez, enquanto a OR apresentou maiores eficiências de remoção de sais. O sistema piloto de tratamento foi capaz de remover todos os parâmetros estudados. A taxa de recuperação na OR foi de 74,64%.

ABSTRACT Considering the shortage of fresh water availability and an increased demand for water in the world, including Brazil, one of the alternatives for water supply are water desalination systems, which remove salts from brackish or seawater. The objective of this study was to evaluate the efficiency of pilot water desalination system treating brackish water which was obtained mixing fresh water and seawater up to reach 1,500 mg L-1 of total dissolved solids (TDS) concentration. The pilot desalination plant with production capacity of 1.0 m3 h-1 is composed of ultrafiltration (UF) and softener working as a pre-treatment to reverse osmosis (RO). Experiments were performed to analyze some water quality parameters as TDS, electrical conductivity, turbidity, pH, apparent color, alkalinity, total hardness, calcium, magnesium, chlorides, sulfates, and temperature. Osmotic pressure, filtration flow and water recovery rate were also measured for the RO. Analyzing the result obtained, it can be concluded that the efficiency of TDS removal and conductivity were 99%. UF was efficient in removing turbidity, whereas RO reached higher salt removal efficiencies. The pilot plant system could remove all water quality parameters studied. Recovery rate in RO was 74.64%.

Effects of different salinity levels on larval growth and development of disease vectors of Culex species

Aim: To determine species distribution of mosquitoes in coastal brackish wetlands and in paddy field area of Kerala along with the effect of increased salinity on the development and survival of major Japanese encephalitis vectors. Methodology: Mosquito survey was carried out in different sites of coastal brackish water as well as in paddy fields of Alappuzha district. First instar larvae were reared until adult emergence at different constant saline water. Each individual was monitored daily for mortality. Larvae were placed in a plastic container with 200 ml distilled water, which served as controls. Counts of larvae, pupae and adults were recorded every 24 hr up to adult emergence. Results: The collected mosquitoes were Culex tritaeniorhynchus, Cx. gelidus, Cx. sitiens, Cx. quinquefasciatus, Cx. bitaeniorhynchus and Anopheles vagus. During summer season, Cx. sitiens (92.85%) was the predominant species followed by Cx. tritaeniorhynchus (2.97%) and Cx. gelidus (2.25%). In saline tolerant study, the maximum adult emergence occurred at 5 parts per thousand. The number of larvae surviving till adult stage decreased progressively with increased salinity. The wing size decreased significantly with increasing salinities, except those reared in 5ppt. Interpretation: The present study demonstrates that these three mosquitoes have the ability to oviposit and breed in brackish water. The study also reveals the health risks associated with vector mosquitoes developing and their frequency of abundance in brackish water, particularly in the context of rising sea levels due to global warming.

Acute toxicity of nitrate in Litopenaeus vannamei juveniles at low salinity levels / Toxicidade aguda do nitrato em juvenis de Litopenaeus vannamei em baixa salinidade

ABSTRACT: Different technologies have been developed to improve the performance of Litopenaeus vannamei in low salinity, mainly in super-intensive systems like recirculation and BFT (Biofloc Technology System) systems. However, there is an accumulation of toxic nitrogenous compounds to the shrimps such as nitrate, that at high concentrations and depending on the salinity of the culture water can be lethal. Acute toxicity tests allow to analyze the relationship between the compound and other abiotic or biotic variables. The aim of this research was to determine the acute toxicity and safety level of nitrate (N-NO3 -) for juveniles of L. vannamei at salinities of 5 and 10g.L-1. For salinity of 5g.L-1, a control and 5 treatments were tested, with nitrate concentrations of 100, 500, 1500, 2500 and 3500mg.L-1.For salinity of 10mg.L-1, a 4500mg.L-1nitrate concentration was added. Juveniles were exposed to concentrations during 24, 48, 72, 96 hours in static system. The Mean Lethal Concentration (LCC50) was calculated and the recommended safety level for L. vannamei cultivation is 60.05 and 127.61mg.L-1 of nitrate for salinities 5 and 10g.L-1, respectively.

RESUMO: Diferentes tecnologias foram desenvolvidas para melhorar o desempenho do Litopenaeus vannamei em baixa salinidade, principalmente em sistemas super intensivos como sistema de recirculação e BFT (Biofloc Technology System). No entanto, há um acúmulo de compostos nitrogenados tóxicos aos camarões, como o nitrato, que em altas concentrações e dependendo da salinidade da água pode ser letal. Os testes de toxicidade aguda permitem analisar a relação entre o composto e outras variáveis ​​abióticas ou bióticas. O objetivo deste trabalho foi determinar a toxicidade aguda e o nível de segurança do nitrato (N-NO3 -) em juvenis de L. vannamei nas salinidades de 5 e 10g.L-1. Para a salinidade de 5g.L-1, um controle e cinco tratamentos foram testados, com concentrações de nitrato 100, 500, 1500, 2500 e 3500mg.L-1. Para salinidade de 10mg.L-1, foi adicionada uma concentração de nitrato de 4500mg.L-1. Os juvenis foram expostos às concentrações durante 24, 48, 72, 96 horas em sistema estático. A Concentração Letal Média (CL50) foi calculada e o nível de segurança recomendado para o cultivo de L. vannamei é de 60,05 e 127,61mg.L-1 de nitrato para salinidadesde 5 e 10g.L-1, respectivamente.

Notes on Halicyclops (Copepoda, Cyclopoida, Cyclopidae) from Colombia and the western Caribbean: a new record with a key to species of Group "B" sensu Rocha (1991) / Notas sobre Halicyclops (Copepoda, Cyclopoida, Cyclopidae) de Colombia y el Caribe occidental: un nuevo registro con una clave para las especies del Grupo "B" sensu Rocha (1991)

Three species of brackish waters microcrustaceans are herein recorded; they belong to the cyclopoid copepod genus Halicyclops and were collected from a coastal system in northern Colombia: H. exiguus Kiefer, 1934,H. venezuelaensis Lindberg, 1954, and H. hurlberti Rocha, 1991. The former has intraspecific variations that deserve further study. The finding of the latter species, previously known from the Eastern Tropical Pacific, represents a new record for Colombia and the Caribbean Sea Basin in the Northwestern Tropical Atlantic. With the finding of H. hurlberti the number of species of Halicyclops known from the Neotropical region and Colombia increases to 20 and 5, respectively. The regional diversity of the genus is probably underestimated. A key to species of the genus belonging to group "B" sensu Rocha (1991) is also provided.

Se registran tres especies de microcrustáceos de aguas salobres; son copépodos ciclopoides del género Halicyclops procedentes de un sistema costero en el norte de Colombia: H. exiguus Kiefer, 1934, H. venezuelaensis Lindberg, 1954 y H. hurlberti Rocha, 1991. La primera especie tiene una variación intraespecífica que merece estudios más profundos. El hallazgo de la última especie es conocida sólo en el Pacífico Tropical Oriental, representa un registro nuevo para Colombia y la cuenca del Mar Caribe en el Atlántico tropical noroccidental. Con el hallazgo de H. hurlberti, la cantidad de especies de Halicyclops reconocidas en la región Neotropical y Colombia aumenta a 20 y 5, respectivamente. La diversidad regional del género probablemente está subestimada. Se proporciona una clave para las especies del género que pertenecen al grupo "B" sensu Rocha (1991).

Characterization and flocculation properties of a carbohydrate bioflocculant from a newly isolated Bacillus velezensis 40B.

In this study, a bioflocculant with a high flocculation activity (>98%) produced by strain 40B, which was isolated from a brackish water was investigated. By 16S rDNA sequence analysis, strain 40B was identified as Bacillus velezensis. Chemical analysis of the bioflocculant 40B indicated that it contained 2% protein and 98% carbohydrates. FTIR analysis showed the presence of carboxyl, hydroxyl and amino groups, which were preferred for the flocculation process. The optimal concentration for the flocculation activity was 3.5 mg l-1. This polysaccharide could also flocculate kaolin suspension over a wide range of pH (1–10) and temperature (5–85 °C) in the presence of CaCl2. The stability of the bioflocculant 40B under various conditions suggests its possible use in the industries and environmental applications. However, no previous report exists on the isolation and characterization of a bioflocculant from the Bacillus velezensis.

Selection of Arthrospira platensis strains with productivity in brackish water with high boron levels for commercial production in the Lluta Valley

Adaptation and selection of Arthrospira platensis strains, for cultivation in brackish water with excess boron (B) in the Lluta Valley can become an interesting alternative that would allow to extend these cultures to areas that possess the environmental conditions, but that lack the fresh water needed to do it. Strains TX98 and P88 were evaluated in laboratory conditions with three different media of brackish water and with the white medium, the Zarrouk modified medium (MZM). The growing media with brackish water with a B concentration present in the Lluta River of 20 mgL-1 (B20) and medium with 30 mgL-1 (B30), and 10 mg L-1 of B (B10). The effect of the different media on the growing parameters with a culture temperature of 25 +/- 1ºC in the three treatments, strains TX98 and P88 triplicate, Arthrospira platensis, showed tolerance. It was statistically determined that in the growth, the two strains, the three treatments and in the interrelation of both there were significant differences (p < 0.05). The TX98 strain reached a concentration of 1.139 g L-1 (dry weight) in brackish water with medium B20. Therefore, the highest rate of specific growth (μmax) was obtained with the TX98 strain grown in the brackish medium B30 and the lowest duplication time (0.597 days). Cells grown in brackish water with B had a slightly biochemically modified composition with the white, in relation to the protein content, in the cases in which there are differences in the B content, specifically B30 treatment. For the culture with brackish water from the Lluta River, the TX98 strain is recommended with 10 mg of B using a laboratory to pilot scale.

A Human Case of Clinostomum complanatum Infection in Korea

A 33-year-old Korean man visited a medical clinic with complaints of throat discomfort and pain for one week. The symptoms occurred one day after eating raw brackish water fish, perch. Endoscopy revealed a fluke, about 5 mm in length, attaching to and peristaltically moving on the surface of the mucosa at the arytenoid region of the larynx. Microscopically, the testes were triangular, tandem, and separated by the uterus. The ovary and cirrus pouch were placed apart from median line between testes. Numerous blood cells were observed in the ceca. The worm was identified to be Clinostomum complanatum. This is the second human case of clinostomiasis in Korea.

Fish-borne Zoonotic Trematode Metacercariae in the Republic of Korea

The prevalence of fish-borne trematodes (FBT), including Clonorchis sinensis, is still high in riverside areas of the Republic of Korea. The author reviewed the detection and identification methods, differential keys, fish intermediate hosts, and morphological characteristics of FBT metacercariae. FBT metacercariae found in freshwater fish are classified mainly into 4 families, i.e., Opisthorchiidae, Heterophyidae, Echinostomatidae, and Clinostomidae. The metacercariae of C. sinensis, found in 40 species of freshwater fish, are elliptical and 0.15-0.17 x 0.13-0.15 mm in size, have nearly equal sized oral and ventral suckers, brownish pigment granules, and an O-shaped excretory bladder. Their general morphologies are similar to those of Metorchis orientalis (except in the thickness of the cyst wall). Metagonimus spp. (M. yokogawai, M. takahashii, and M. miyatai) metacercariae are subglobular or disc-shaped, and 0.14-0.16 mm in diameter. They have yellow-brownish pigment granules, a ventral sucker deflectively located from median, and a V-shaped excretory bladder. The metacercariae and fish intermediate hosts of Centrocestus armatus, Clinostomum complanatum, and 3 echinostomatid flukes (Echinostoma hortense, E. cinetorchis, and Echinochasmus japonicus) were summarized. FBT metacercariae detected in brackish water fish are mainly members of the Heterophyidae. The morphological characters, identification keys, and fish intermediate hosts of 7 species (Heterophyes nocens, Heterophyopsis continua, Pygidiopsis summa, Stellantchasmus falcatus, Stictodora fuscata, Stictodora lari, and Acanthotrema felis) were also reviewed. The contents treated in this study will provide assistance at the laboratory bench level to those working on recovery of metacercariae from fish hosts and identifying them.

Identification of Acanthotrema felis (Digenea: Heterophyidae) metacercariae encysted in the brackish water fish Acanthogobius flavimanus

The metacercariae of Acanthotrema felis Sohn et al., 2003 (Digenea: Heterophyidae) were discovered in a species of the brackish water fish, Acanthogobius flavimanus, in the Republic of Korea. They were experimentally fed to kittens, and adult flukes were harvested 7 days later. The adults were morphologically characterized by the presence of a bipartite seminal vesicle, the ventral sucker associated with a ventrogenital sac enclosing 3 sclerites (2 long and pointed, and 1 short and thumb-like), and an unarmed gonotyl. The adult flukes were identified as A. felis Sohn et al., 2003, and the brackish water fish A. flavimanus has been verified as one of its second intermediate hosts.