Algae Inflow Monitoring using Satellite Images for the Process Control of the Gijang Desalination Plant in Busan, South Korea

Sustainable Aquaculture Futures

Jeong, J.-Y.; Kang, Y.H.; Park, K.; Um, J.-H., and Son, Y.B., 2018. A bio-physical assessment of Harmful Algal Bloom (HAB) outbreak using multi-dimensional array data during 1998–2017. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 836–840. Coconut Creek (Florida), ISSN 0749-0208.Harmful algal blooms (HABs), Cochlodinium polykrikoides, which related a devastating algal bloom, recently have caused the serious problems of fishery and aquaculture activities in the south coast of Korea (SCK). To understand the evolution of red tide and determine physical factors as a function of the bloom occurrence and disappearance, we used the multi-dimensional data (satellite and in-situ) during 1998–2017. Red tides generally have started with finishing the raining season and then increased with increasing the sea surface temperature and tidal range. To understand the general trend of red tide occurrence, we classify three different scales with cell density, area, and duration of red tides such as small, medium, and large scale red tides. Small and medium scale red tides started in the middle of August. The periods of the maximum cell density and extinction were shown in the early and end of September. SST in small and medium scale red tides was higher than in large scale red tides. Even though the tidal range was relatively small at the beginning of the outbreak, it was increased in the maximum cell density and decreased in the extinction period. Large scale red tides began in the early of August and the maximum cell density appeared at the end of August. SST was the lowest and the tidal range was the largest difference in the beginning outbreak and the lowest difference in the maximum cell density. In particular, the phenomenon of large-scale variation in the overall time series was that the SST and PAR in large scale red tides were relatively low compared to the small and medium scale red tides. Even though the tidal range was less difference before the beginning outbreak, it is analyzed that there was a growing difference in time.

Keeping Tabs on HABs: new tools for detecting, monitoring, and preventing harmful algal blooms.

Harmful Algal Blooms (HABs) have significant ecological and economic effects on the marine environment and use. In recent years, researchers have been increasingly developing and testing methods to treat and control HABs. General categories or strategies proposed as HAB control technologies include mechanical, biological, chemical, genetic, and environmental controls. The authors of this paper suggest using floating desalination plants to treat or control red tides. HAB producing dinoflagellates have been shown to be sensitive to physical and chemical changes in the environment, such as changes in temperature and salinity. The typical response of dinoflagellates is to form cysts that then settle out of the water column. The discharges from a floating desalination and water pumping plant can rapidly change the temperature and salinity in the water column. These changes could be expected to induce encystment in the dinoflagellate species that form cyst and could cause mortality in those species unable to form temporary cysts. Preventing population growth, inducing encystment, or causing mortality would effectively end a HAB. Discharges from a desalination plant are temporary in nature and include hypersaline water, freshwater (hyposaline water), and heated warmer. By discharging the heated hyposaline water at a low depth in the water column, due to its lower density than seawater, the discharge would move upward towards the surface. Since the hypersaline water would be denser than seawater, by discharging it at the surface, the hypersaline water would sink. In environments where a stratified water column exists, pumping water could disrupt the stratification without the need for additional desalination. The discharges from a floating desalination plant would stress the red tide with surfacing warmer fresh water and sinking hypersaline water. The stresses caused by these disturbances can disrupt a HAB. These temperature and salinity changes that could be created by a floating desalination plant would be achieved without the discharge of chemicals or other materials that could have other detrimental environmental impacts. A good aspect of this treatment is that, with continued mixing after discharge, the water would return to ambient temperature and salinity relatively quickly with minimal effect on the marine environment. Since the dinoflagellates have been shown to react quickly to environmental changes, the temperature and salinity of the discharges could be controlled to reduce adverse impacts on other marine organisms. B

The anatomy of the crab Neptunus sanguinolentus Herbst. IV. Reproductive system and embryological studies : George M. J., 1963. J. Madras Univ., (B) 33 (3): 289–304.

Palynological records of red tide-producing species in Canada: past trends and implications for the future

In recent decades, the importance of long-term ecological research (LTER) has been highlighted because of the growing interest in global environmental changes. Specifically, LTER data allows one to track the history of target ecosystems (e.g., trends of particular ecological entities) and enables one to understand the causal relationships of ecosystem functioning. One ecological problem is harmful algal blooms (HABs) in freshwater environments. It is generally perceived that global warming and local eutrophication are responsible for serious and frequent HAB events, and various efforts have been made to explain and forecast HABs. LTER data for HABs typically consist of various forcing functions and variables; thus, the selection of appropriate data-analysis methods for a HAB database is necessary. This chapter presents a series of studies related to the prediction and elucidation of two HABs, such as summer cyanobacteria (e.g., Microcystis aeruginosa) and winter diatom (e.g., Stephanodiscus hantzschii) that occur in the regulated Nakdong River, South Korea. First, HABs, water quality, and zooplankton patterns were analyzed using self-organizing maps (SOMs). Those major factors that have a close relationship to HABs, i.e., water temperature, pH, and rainfall, were selected. We created a predictive model and control scenario for HABs using a variety of methods (evolutionary computation, artificial neural network) in the real world based on confirmed information. We also suggest potential further studies of the Nakdong River.

Red tide is a temporary natural phenomenon involving harmful algal blooms (HABs) in company with a changing sea color from normal to red or reddish brown, and which has a bad influence on coast environments and sea ecosystems. The HABs have inflicted massive mortality on fin fish and shellfish, damaging the economies of fisheries for almost every year from 1990 in South Korea. There has been a lot of study on red tide due to increasing of red tide damage. However, internal study of automatic red tide image classification is not enough. Especially, extraction of matching center of image features for recognizing algae image object is difficult because over 200 species of algae in the world have a different size and features. Besides, the accuracy of algae image recognition of various species is low since previous red tide recognition methods mostly use a few species of red tide harmful algae images for training of classification. In order to resolve the above limitation, this paper proposes the red tide algae image recognition method using rotation of image angle and semantic feature based on NMF (nonnegative matrix factorization). The experimental results demonstrate that the proposed method achieves better performance than other red tide recognition methods.

Chapter 9 - Satellites-Based Monitoring of Harmful Algal Blooms for Sustainable Desalination

Harmful algal blooms (HABs) are a major environmental problem in all 50 US states and nearly every country around the world. Best known as “red tide,” HAB events are capable of imposing severe impacts on human health, aquatic life, and ecosystems. Because environmental impacts to aquatic ecosystems can be as large and significant as those associated with chemical contamination, HABs should be included routinely as a contaminant of potential concern when monitoring and assessing the impact of anthropogenic activities on aquatic ecosystems. The economic impact in the US alone is considerable. According to Hoagland and Scatasta (2006), the cost of coastal HAB events is at least $82 million/y with the majority of the impact on the public health and commercial fisheries sectors. The National Centers for Coastal Ocean Science believes the costs are far greater due, in part, to the lack of information about individual events, unquantified economic effects of environmental impacts, and sociocultural impacts such as loss of cultural practices and values, increased reliance on social services, decreased recreational opportunities, and shifts in livelihoods. The ecological impact can be devastating. HAB events are capable of generating natural toxins that can cause large-scale mortalities of fish, turtles, birds, and aquatic mammals (e.g., dolphins, manatees, and whales) (Landsberg 2002). HAB events are triggered by sudden increases in populations of diatoms, dinoflagellates, and cyanobacteria (i.e., blue-green algae); their adverse effects can be direct (i.e., poisoning via the production of neurotoxins [e.g., cyanotoxins], asphyxiation via disruption of gill tissues, or asphyxiation from O2 depletion in the water column), or indirect (i.e., ingestion of food contaminated with algal toxins, loss of top predators) (Hallegraeff 1993). Terrestrial animals such as dogs and cattle, as well as humans, can also be affected by drinking water or eating food containing algal toxins, and the aesthetic impacts can be immense (Jacobs 2013). HABs are global phenomena that are not restricted to any specific geographic regions. They are increasing in frequency, intensity, and duration in freshwater, transitional (e.g., estuarine), and marine environments (Pavagadhi and Balasubramanian 2013; Quiblier et al. 2013; Wetz and Yoskowitz 2013). For example, an unusually large, long-lasting HAB in 2015 shut down shellfish fisheries along the west coast of North America (http://phys.org/news/2015-06-massive-algal-bloom.html). There is no single environmental condition that triggers a HAB event. In some cases, HABs appear to be caused by increased anthropogenic loadings (e.g., the release or accumulation of excessive nutrients, iron, and other essential elements) into fresh and coastal waters; in other cases, HABs result from natural factors including coastal upwelling, El Niño events, and inputs of wind-borne, iron-rich dust from the Sahara and other desert areas (Moore et al. 2008). Co-occurrence of HAB events with increasing surface water temperatures, ocean acidification, and changes to upwelling, precipitation, and evaporation patterns suggests that global climate change also may be a contributing factor (Dale et al. 2006; Moore et al. 2008; Jarvie et al. 2012). My personal experience with HABs, aside from exercising caution in eating coastal shellfish, includes a coastal marine pulp mill in Alaska (United States) associated with extensive fish mortalities, and a coal mine in Alberta (Canada) linked to the deaths of a dog and 2 cows that drank the water from a tailings pond. In both cases, regulators and the public assumed that the primary culprit was one or more chemical contaminants in the effluent. A great deal of time and effort was spent investigating these “usual culprits” before any thought was given to the possibility of HABs. The fish, dog, and cows all died from HAB neurotoxins. The coal mine now monitors for the presence and abundance of potentially harmful algae, as do other mines in the region; however, this is not yet common practice for anthropogenic discharges to aquatic ecosystems. It should be. To date, ecotoxicologists, aquatic ecologists, and other professionals involved in contaminant monitoring and assessment rarely consider the possibility of a biological condition as the cause of environmental damages or poisoning of wildlife or livestock. HABs are not typically listed as contaminants (or stressors) of potential concern in ecological or human health risk assessments. Chemicals are the usual suspects, for example, in agricultural run-off, effluent discharges, sediments, and storm water. We should no longer view the environment narrowly and need to adopt a wider view that includes serious consideration of biological contamination. HABs, in particular, need to be considered routinely in ecological and human health risk assessments involving the aquatic environment. More research is needed to better understand how and why HABs occur and to identify the relationships between physical and chemical conditions and biological interactions. There is evidence, for example, that selective feeding by zooplankton on nontoxic algae may be a mechanism facilitating the formation of certain HAB events (Scotti et al. 2015). The effects of HABs on aquatic ecosystem function and services should be included in assessments of coastal and freshwater environmental management planning, with emphasis on reducing their occurrence, intensity, and ecological impacts. There is ample evidence indicating that HABs are becoming a significant global environmental problem. The time has come to afford this biological phenomena its due consideration as a globally persistent and increasingly problematic contaminant of potential concern. Peter M Chapman Senior Editor Integrated Environmental Assessment and Management North Vancouver, British Columbia, Canada

More than 1,000 manmade satellites currently orbit our planet.1 Some are near the edge of the Earth’s atmosphere just a few hundred kilometers up. Others are tens of thousands of kilometers above us.2 They aid in communication, navigation, defense, and science. A small number3,4 play a critical and quickly expanding role: monitoring the Earth’s surface and atmosphere to track environmental conditions that are intimately tied to human health. A number of new Earth-observing missions are planned for the next decade, including Sentinel-5 aboard the European Space Agency’s MetOp Second Generation satellites (pictured).48 In the meantime researchers are finding new uses for the satellite ... Researchers and government agencies worldwide already use satellite data to monitor air pollutants, infectious disease epidemics, harmful algal blooms (HABs), climate change, and more. But as current research indicates, that’s only the beginning of what we can do with the technology, broadly referred to as “remote sensing.” In the coming years, new satellites will offer higher-resolution imagery in conjunction with more robust and precise algorithms to process the data they deliver. As a result, researchers expect to dramatically expand their ability to view and understand Earth’s land, water, and air, from its remotest ocean waters to its largest cities. The National Aeronautics and Space Administration (NASA) launched its first satellite in 1958,5 and TIROS-1, the country’s first meteorological satellite, came 2 years later.6 Within a few decades members of the epidemiological and public health communities began actively looking at satellite data, says John Haynes, program manager of the NASA Applied Sciences Health and Air Quality Applications Program. In recent years interest in remote-sensing data has soared, with newer avenues being developed and fine-tuned, including air-quality measurements and vector-borne disease projections. “There’s really been a paradigm shift in the use of remote sensing for public health issues,” Haynes says. “Every year there seems to be more and more interest.” Indeed, by March 2015 NASA will have launched 6 Earth-observing missions in 12 months,7 more than in any year in at least a decade.8 New launches include a “global precipitation observatory” that will make frequent global measurements of rain and snowfall, plus one satellite designed to measure soil moisture and another that will measure how carbon moves through the Earth’s atmosphere, land, and oceans. In addition, the International Space Station will receive three new instruments, one that will observe how winds behave around the world, one that will measure clouds and aerosols (particles suspended in the atmosphere)—two variables that remain difficult to predict in climate-change models—and one that will take global, long-term measurements of key components of the Earth’s atmosphere, including aerosols and ozone.9 The momentum will carry through at least the next 8 or so years, with NASA and other space agencies in Europe and Asia planning to launch new satellites that will provide even higher-resolution snapshots of the Earth. Along with technological and scientific advances, a third development is leading to new and improved applications of satellite data: NASA and the National Oceanic and Atmospheric Administration (NOAA) have made their satellite data available free of charge, Haynes says, while the European Space Agency (ESA) has reduced prices and promised to provide free access to data from its next generation of instruments. “More people use the data, and you get more out of it than when you try to restrict it,” says Raphael Kudela, an oceanographer at the University of California, Santa Cruz, who uses satellite imagery to study HABs. This free sharing of data has been instrumental in his field, allowing researchers at institutions around the world to study HABs from above and to improve systems to track and predict them.

Abstract. Cochlodinium polykrikoides (C. polykrikoides) is a phytoplankton that causes red tides every year in the middle of the South Sea of Korea. C. polykrikoides is a harmful Algae that has migratory ability and causes the fisheries damage over a long period of wide sea area if it causes red tide once. To minimize red tide damage, it is important to anticipate and prepare the red tide occurrence timing and location in advance. In this study, we predicted the occurrence of red tide of C. polykrikoides using machine learning techniques and compared the results of each algorithm. Logistic regression model, decision tree model, and multilayer neural network model were used for prediction of red tide occurrence. To produce the data set for model learning, we used the red tide occurrence map provided by the National Institute of Fisheries Science, the Local Data Assimilation and Prediction System (LDAPS) provided by the Korea Meteorological Agency, and the G1SST provided by the National Oceanic and Atmospheric Administration (NOAA). The feature vectors used for modeling consisted of 59 elements, which were made by using temperature, water temperature, precipitation, solar radiation, wind direction and wind speed. Only a very small number of red tide cases can be collected compared to the case of no red tide cases. Thus, an imbalance data problem arises in the data set. To overcome this imbalanced data problem, we used adding noise after oversampling to data of red tide occurrence to solve the difference of data between two classes.The data set is divided into 8 : 2 to prevent over-fitting and 80% is used as the learning data. The remaining 20% was used to evaluate the performance of each model. As a result of evaluating the prediction performance of each model, the multilayer neural network model showed the highest prediction accuracy.

적조는 유해 조류의 이상 대량번식으로 바닷물의 색이 적색이나 황색으로 변하며, 어패류를 대량으로 집단 폐사시키는 등 바다환경에 좋지 않은 영향을 미치는 전 세계적인 자연현상이다. 국내에서는 90년대 이후로 어패류 양식장에 지속적인 피해를 입히고 있다. 적조 생물에 대한연구는 수산업 피해가 증가함에 따라서 많은 연구가 이루어지고 있다. 그러나 자동으로 적조 이미지를 인식하여서 유해적조를 판별하는 적조이미지 검색에 대한 국내의 연구는 미흡한 실정에 있다. 특히 전 세계적으로 200여종의 적조 생물은 각기 다른 크기와 모양을 가지고 있기 때문에 이미지 인식을 위한 기준 특징을 추출하기 어렵다. 이 때문에 기존이 연구들은 몇 종류의 적조 생물만을 이미지 인식에 이용하고 있다. 본 논문은 이러한 문제를 해결 할 수 있도록 NMF(non-negative matrix factorization, 비음수 행렬분해)와 이미지의 회전각 보정을 이용한 새로운 적조 이미지 인식 향상방법을 제안한다. Red tide is a temporary natural phenomenon involving harmful algal blooms (HABs) in company with a changing sea color from normal to red or reddish brown, and which has a bad influence on coast environments and sea ecosystems. The HABs have inflicted massive mortality on fin fish and shellfish, damaging the economies of fisheries for almost every year from 1990 in South Korea. There have been many studies on red tide due to increasing damage from red tide on fishing and aquaculture industry. However, internal study of automatic red tide image classification is not enough. Especially, extraction of matching center features for recognizing algae image object is difficult because over 200 species of algae in the world have a different size and features. Previously studies used a few type of red tide algae for image classification. In this paper, we proposed the red tide image recognition method using NMF and revison of rotation angle for enhancing of recognition of red tide algae image.

Combination of ocean acidification and warming enhances the competitive advantage of Skeletonema costatum over a green tide alga, Ulva linza

Studies on Algae (HA) are rare in the Indian Ocean around Sri Lanka. The current study investigated diatoms and dinoflagellates in five Sri Lankan Southern coast locations, focusing on potentially harmful species. A total of twenty-seven diatom species and ten dinoflagellate species were identified during the study. Among them, eight diatom species (Asterionellopsis glacialis, Chaetoceros curvisetus, Chaetoceros lorenzianus, Guinardia flaccida, Leptocylindrus minimus, Nitzschia sp., Proboscia alata and Pseudonitzschia fraudulenta) and three dinoflagellate species (Ceratium fusus, Ceratium furca, and Dinophysis caudata) were identified as potentially harmful species. Specifically, P. fraudulenta related to producing domoic acid, causing Amnesic Shellfish Poisoning (ASP), was recorded in all sampling locations. Potentially harmful species showed a significant correlation with turbidity and total phosphorus levels (p < 0.05). Discerning the occurrence of these species in the region is vital, as the seascape under investigation is in anthropogenic pressure with many sea routes. Even though bloom conditions were not observable during the study period, the risk of transporting microalgae to many different locations and the possibility of bloom formations cannot be ignored. As a country surrounded by the ocean, the results demonstrated the importance of continuous monitoring of potentially HA and regulating maritime and land-based activities, covering a broader area to identify and manage potential threats to the Indian Ocean. Keywords: Indian Ocean; Sri Lanka; coastal zone; harmful algae; diatoms; dinoflagellates; water quality References Al-kandari, M., Al-Yamani, F. & Al-Rifaie, K. (2009). Marine phytoplankton atlas of Kuwait's waters. Kuwait Institute for Scientific Research. Kuwait. Almandoz, G.O., Fabro, E., Ferrario, M., Tillmann, U., Cembella, A. & Krock, B. (2017). 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