Water circulation and impact on water quality in the southwest of Efate Island, Vanuatu

In this study, results are presented for depth-specific hydraulic and water quality surveys, as well as meteorological observations, at key monitoring sites in the Paldang Reservoir, South Korea. These results were used to determine the water circulation characteristics that represent the main contributors to water quality changes. In the section before the confluence point of the two rivers, a different type of two-layer flow appeared for each. In the North Han River, backwater flowing backward in the upstream direction occurred in the surface layer, and was accompanied by two-layer flow, during the zero-discharge period of the Cheongpyeong Dam. On the other hand, in the South Han River, two-layer flow was observed in the upper layer in the downstream flow, and the thickness of upper and lower layers varied depending on the discharge rate of the Paldang Dam. Strong flow fluctuations were observed near the Paldang Dam (3 km upstream), and these were dependent on its instantaneous discharge rate. In particular, if the instantaneous discharge from the Paldang Dam remained below 400 m3/s for several days, the flow velocity in the lower layer decreased below 2 cm/s or no flow occurred. The comparison between flows during different periods associated with depth-specific water temperature variations showed that the average flow prevailed across all layers in the downstream direction at all monitoring sites during the vertical mixing period. In contrast, spatiotemporal variations in flow, such as two-layer flow and backwater, were observed during the stratification period in the South Han River and the North Han River. This led to increased residence times and vertical stability, thus creating favorable conditions for algal blooms.

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Stratified Water Circulation Forecasting for Water Quality Management Planning in the Coastal Zone

10.1109/oceans.1978.1151178 ◽

1978 ◽

Author(s):

S. Chamberlain ◽

P. Tawari ◽

W. Comery

Keyword(s):

Water Quality ◽

Quality Management ◽

Coastal Zone ◽

Water Quality Management ◽

Water Circulation ◽

Management Planning

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Sistem Akuaponik untuk Peternakan Lele dan Tanaman Kangkung Hidroponik Berbasis IoT dan Sistem Inferensi Fuzzy

Jurnal Teknologi Informasi dan Ilmu Komputer ◽

10.25126/jtiik.0814025 ◽

2021 ◽

Vol 8 (1) ◽

pp. 157

Author(s):

Fachrul Rozie ◽

Iwan Syarif ◽

Muhammad Udin Harun Al Rasyid ◽

Edi Satriyanto

Keyword(s):

Water Quality ◽

Internet Of Things ◽

Fuzzy Inference System ◽

Fuzzy Inference ◽

Smart Phone ◽

Fish Farming ◽

Water Circulation ◽

Inference System ◽

And Control ◽

Internet Of Things Technology

Akuaponik adalah penggabungan sistem budidaya akuakultur dan hidroponik yang dapat menjadi solusi untuk mengatasi keterbatasan lahan, keterbatasan sumber air serta meningkatkan ketahanan pangan. Pada sistem akuaponik, kualitas air pada budidaya ikan merupakan salah satu syarat utama dalam keberhasilan proses budidaya. Penelitian ini mengkombinasikan peternakan lele dengan penanaman kangkung hidroponik. Kotoran ikan lele dan sisa makanan terakumulasi di air dan dapat menjadi racun bagi ikan lele karena mengandung kadar anomia yang tinggi sehingga sangat berbahaya jika tidak dibuang. Air ini kemudian dialirkan ke tanaman kangkung hidroponik melalui biofilter yang bermanfaat sebagai pengurai air kotor dari kolam menjadi nitrat dan nitrit yang berguna sebagai nutrisi tanaman. Selanjutnya setelah air menjadi bersih dan mempunyai kadar oksigen yang tinggi, air tersebut dialirkan kembali ke kolam ikan lele. Penelitian ini bertujuan untuk mengembangkan sistem cerdas pada budidaya akuaponik dengan memanfaatkan teknologi Internet of Things yang dilengkapi dengan beberapa jenis sensor untuk memantau dan mengendalikan kualitas air dengan menerapkan algoritma Sistem Inferensi Fuzzy / Fuzzy Inference System (FIS) untuk mengatur kecepatan sirkulasi air kolam agar menghemat daya listrik pada pompa. Peralatan ini juga dilengkapi dengan layanan pemberian pakan ikan secara otomatis yang dapat diprogram sesuai kebutuhan. Sistem akuaponik ini dapat dipantau melalui web maupun ponsel pintar berbasis android. Pengujian yang dilakukan terhadap perbandingan keputusan oleh pakar dan sistem FIS pada kecepatan sirkulasi air sistem akuaponik menunjukkan nilai akurasi 83,33%, dan hasil dari pengujian ketepatan alat pemberi pakan yang dibuat secara otomatis terhadap ketepatan pemberian pakan secara manual memiliki nilai akurasi 90,97%. AbstractAquaponics is a combination of aquaculture and hydroponic cultivation systems that can be a solution to overcoming limited land, limited water sources and increasing food security. In the aquaponics system, water quality in fish farming is one of the main requirements in the success of the cultivation process. This research combines catfish farming with hydroponic kale cultivation. Catfish feces and food scraps accumulate in water and can be toxic to catfish because they contain high levels of anomia so it is very dangerous if not disposed of. This water is then flowed to hydroponic kale plants through a biofilter which is useful as decomposing dirty water from the pond into nitrates and nitrites which are useful as plant nutrients. Furthermore, after the water becomes clean and has high oxygen levels, the water is flowed back into the catfish pond. This study aims to develop a smart system in aquaponic cultivation by utilizing Internet of Things technology which is equipped with several types of sensors to monitor and control water quality by applying the Fuzzy Inference System (FIS) algorithm to regulate the speed of pool water circulation in order to save electric power on the pump. This equipment is also equipped with an automatic fish feeding service which can be programmed as needed. This aquaponics system can be monitored via the web or an Android-based smart phone. Tests carried out on the comparison of decisions by experts and the FIS system on the water circulation speed of the aquaponics system show an accuracy value of 83.33%, and the results of testing the accuracy of the feeder that is made automatically against the accuracy of manual feeding have an accuracy value of 90.97% .

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EFFECT OF WATER CIRCULATION ON THE TREATED WATER QUALITY OF JOHKASOU - EVALUATION BASED ON MULTIVARIATE ANALYSIS -

Journal of Japan Society of Civil Engineers Ser G (Environmental Research) ◽

10.2208/jscejer.72.iii_255 ◽

2016 ◽

Vol 72 (7) ◽

pp. III_255-III_265

Author(s):

Yasushi ISHIGURO ◽

Yenni TRIANDA ◽

Tomonari FUJISAWA ◽

Katsuhito YASUFUKU ◽

Shinya OKUMURA ◽

...

Keyword(s):

Water Quality ◽

Multivariate Analysis ◽

Water Circulation ◽

Treated Water ◽

Effect Of Water

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Dissolution Test Protocol for Estimating Water Quality Changes in Minerals Processing Plants Operating With Closed Water Circulation

Minerals ◽

10.3390/min10080653 ◽

2020 ◽

Vol 10 (8) ◽

pp. 653

Author(s):

Thi Le ◽

Nóra Schreithofer ◽

Olli Dahl

Keyword(s):

Water Quality ◽

Potential Effect ◽

Water Circulation ◽

Experimental Methodology ◽

Process Water ◽

Quality Data ◽

Water Composition ◽

Closed Water ◽

Flotation Performance ◽

Minerals Processing

To save freshwater resources and comply with environmental regulations, minerals processing operations are transitioning to partially or fully closed water circulation. However, the accumulation of electrolytes and the addition of reagents lead to changes in water composition and may compromise flotation performance and plant maintenance. As a consequence, costly modifications are often required to cope with these challenges. Therefore, knowledge about water quality variation owing to closed water circulation and its potential effect on the flotation performance is crucial. The experimental methodology presented in this paper targeted three main objectives: (1) predicting the tendency of the accumulation of elements and compounds into the process water during comminution, flotation, and storage in tailings facilities; (2) establishing a relationship between laboratory results and plant historical water quality data; and (3) predicting the potential effect of recycling water on flotation performance. The results obtained with Boliden Kevitsa ore showed a good correlation between the water matrix of the actual process water on-site and that obtained in the ore dissolution tests done in the laboratory. The final water composition came close to the process water in terms of major elements and some of the minor elements. Additionally, the work presented in this paper demonstrated that a dissolution loop allowed us to predict the potential impact of the recycling water on the ore flotability. This methodology could serve as an aid for predicting water quality matrix variation and designing closed water circulation systems at existing and new plants.

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The effectiveness of filters on catfish Clarias gariepinus fry performance in the aquaponic system

Jurnal Akuakultur Indonesia ◽

10.19027/jai.20.2.101-114 ◽

2021 ◽

Vol 20 (2) ◽

pp. 101-114

Author(s):

Yuli Andriani ◽

Zahidah Hasan ◽

Irfan Zidni ◽

Isni Nurruhwati ◽

Iskandar Iskandar ◽

...

Keyword(s):

Water Quality ◽

Survival Rate ◽

Growth Performance ◽

Clarias Gariepinus ◽

Stocking Density ◽

Water Circulation ◽

Filter Medium ◽

Feed Conversion ◽

Water Spinach ◽

Absolute Growth

This study aimed to determine the effectiveness of filters on the growth performances of catfish fry (Clarias gariepinus) in the aquaponic system. The study was conducted in the Ciparanje Green House, Faculty of Fisheries and Marine Sciences, Universitas Padjadjaran, Jatinangor. A completely randomized design with four treatments and three replications was applied, namely treatment A: Water circulation using bioball filter medium, B: Water circulation using water spinach filter medium, C: Water circulation using bioball and water spinach filter media, and D: Water circulation using sponge filter medium (control). The container used for the maintenance was a fiber tank at 70 cm × 70 cm × 70 cm size filled with 257 L water and a stocking density of 15 fish/fiber. The parameters observed were survival rate, growth, feed conversion, and water quality. The results showed that the use of biological filter using water spinach produced the best growth performance of catfish. The best survival rate was also obtained by using water spinach filter (100%) with the absolute growth of 98.32 ± 15.6 g. The water quality an aquaponic system with water spinach filter supported the growth performance of catfish fry. Keywords: absolute growth, aquaponic, Clarias gariepinus, filters. ABSTRAK Penelitian ini bertujuan untuk menguji efektivitas filter terhadap performa pertumbuhan benih ikan lele Clarias gariepinus dalam sistem akuaponik. Penelitian dilakukan di Laboratorium Rumah Kaca Ciparanje, Fakultas Perikanan dan Ilmu Kelautan, Universitas Padjadjaran, Jatinangor. Metode penelitian adalah rancangan acak lengkap dengan empat perlakuan dan tiga ulangan, yaitu perlakuan A: sirkulasi menggunakan media filter bioball, B: Sirkulasi menggunakan media filter bayam air, C: Sirkulasi menggunakan media filter bioball dan tanaman kangkung, dan D : Sirkulasi menggunakan media spons (kontrol). Wadah yang digunakan untuk pemeliharaan bak fiber dengan ukuran 70 cm × 70 cm × 70 cm diisi dengan air sebanyak 257 L dengan padat tebar 15 ekor / bak. Parameter yang diamati adalah kelangsungan hidup, pertumbuhan ikan, konversi pakan dan kualitas air. Hasil penelitian menunjukkan bahwa penggunaan filter biologis menggunakan tanaman kangkung menghasilkan performa pertumbuhan ikan lele yang terbaik. Tingkat kelangsungan hidup terbaik juga ditunjukkan oleh pelakuran dengan filter berupa tanaman kankung (100%) dan pertumbuhan mutlak 98,32 ± 15,6 g. Kualitas air sistem akuaponik dengan filter tanaman kangkung mendukung performa pertumbuhan benih ikan lele.

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Fragmentation method of coral (Caulastrea furcata) for growth measured at controlling condition

Acta Aquatica Aquatic Sciences Journal ◽

10.29103/aa.v1i1.293 ◽

2014 ◽

Vol 1 (1) ◽

pp. 20

Author(s):

Zulfikar Zulfikar ◽

Dedi Soedharma ◽

Zulfigar Yasin ◽

Aileen Tan Shau Hwai

Keyword(s):

Water Quality ◽

Survival Rate ◽

Water Circulation ◽

Artificial Substrate ◽

Cutting Process ◽

Circulation System ◽

Normal Value ◽

Length Growth ◽

Water Quality Condition ◽

Water Circulation System

The objective of the research are: (1) to analyze the water quality condition of water circulation system at laboratory and (2) to measure the growth (length and height) and survival rate of Caulastrea furcata which was fragmented at the laboratory. The water quality condition at the laboratory showed that every parameter has normal value in which organism can live and grow. Natural feed such as Copepoda and Nannoclhoropsis were also cultured at the laboratory as food for the coral. Transplantation was done by cutting the colony of coral or by breaking the branch of coral into pieces from every kind of coral spesies and placed those on artificial substrate made from ceramic bricks. Cutting process was done after the acclimatization process. Fragmentation treatment of C. furcata become 1 polyp, 2 polyp, 3 polyp and 4 polyp that was reared on circulation system did not give significant impact on height and length growth after 160 days. Mean of growth length of C. furcata on treatment 1, 2, 3 and 4 polyps in every month after 160 days was 1.64 mm, 1.55 mm, 1.42 mm and 1.08 mm, respectively, whereas mean of growth broad was 0.71 mm, 0.82 mm, 0.51 mm and 0.62 mm, respectively. Fragmentation treatment of C. furcata become 1 polyp was best length if compare other treatment.Tujuan penelitian ini adalah: (1) menganalisis kondisi kualitas air pada system sirkulasi air di laboratorium dan (2) mengukur pertumbuhan (panjang dan tinggi) dan tingkat kelulushidupan Caulastrea furcate yang telah difrakmentasi di laboratorium. Nilai kualitas air menunjukkan bahwa setiap parameter adalah normal dan dapat mendukung kehidupan dan pertumbuhan organisme. Pakan alami seperti Copepoda dan Nannoclhoropsis yang juga dikultur di laboratorium sebagai pakan karang. Tansplantasi dilakukan melalui pemotongan koloni karang pada bagian cabang karang kedalam bagian kecil dari setiap spesies karang dan ditempatkan pada subtrak buatan yang dibuat dari keramik. Proses pemotongan dilakukan setelah proses aklimatisasi dilakukan. Perlakuan frakmentasi C. furcate menjadi 1 polip, 2 polip, 3 polip dan 4 polip kemudian didedahkan dalam air berskirkulasi tidak memberikan efek yang signifikan terhadap pertumbuhan tinggi dan panjang setelah 160 hari. Rata-rata pertambahan lebar pada perlakuan 1, 2, 3 dan 4 polip pada setiap bulan setelah 160 hari adalah 1.64 mm, 1.55 mm, 1.42 mm dan 1.08 mm. dimana rata-rata pertumbuhan tinggi secara berurutan adalah 0.71 mm, 0.82 mm, 0.51 mm dan 0.62 mm. Perlakuan frakmentasi 1 polip pada C. furcate menghasilkan panjang terbaik dibandingkan perlakuan lainnya.

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Teknologi Fragmentasi Buatan Karang (Caulastrea furcata dan Cynarina lacrimalis) dalam Upaya Percepatan Pertumbuhan pada Kondisi Terkontrol

Jurnal Natur Indonesia ◽

10.31258/jnat.10.2.76-82 ◽

2012 ◽

Vol 10 (2) ◽

pp. 76

Author(s):

Zulfikar Zulfikar ◽

Dedi Soedharma

Keyword(s):

Water Quality ◽

Survival Rate ◽

Water Circulation ◽

Circulation System ◽

Length Growth ◽

Water Quality Condition ◽

Water Circulation System

The objective of research were analyze water quality condition of water circulation system at laboratory and tomeasured growth survival rate of Caulastrea furcata and Cynarina lacrimalis which was fragmented at laboratory.Fragmentation treatment of Caulastrea furcata become 1, 2, 3, and 4 polyp that was rearing on circulation systemdid not give significant impact on height and length growth after 160 days rearing and fragmentation of Cynarinalacrimalis on circulation system give significant impact. Mean of growth length of Caulastrea furcata on treatment1, 2, 3 and 4 polyp in every month after 160 days was 1.64 mm, 1.55 mm, 1.42 mm , and1.08 mm whereas growthbroad was 0.71 mm, 0.82 mm, 0.51 mm, 0.62 mm, and mean of growth length Cynarina lacrimalis for the sametreatment in every month was 1.47 mm, 0.90 mm, 0.62 mm, 0.61 mm whereas growth broad was 1.57 mm, 1.16mm, 0.93 mm, 0.89 mm. Fragmentation treatment of Caulastrea furcata become 1 polyp was best length if compareother treatment and Cynarina lacrimalis was treatment became 2 devide.

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