Seagrass Research Articles

Discovery of live material of Marginella (Roseamarginella) namaqua

Recently (March 2024) the authors undertook another field trip to the Kalahari and northern West Coast of South Africa. In March 2021 the authors had an expedition through the Kalahari, Karoo and West Coast of South Africa that took them to a little-known fisher’s town, Hondeklip Bay. For background on the town, in 1846, Thomas Grace (a ship’s captain) discovered a small natural harbor and he established a trading station, naming the town after a gneiss rock which vaguely resembles a dog. The name of the town is “Hondeklipbaai”, an Afrikaans name that translates as “dog stone bay” in English. It became the preferred harbor of export for copper ore, until the harbor in Port Nolloth was developed in the 1850s. Alluvial diamond-mining operations started in the area in 1970 and constitutes the main business of mines in that area of the Northern Cape (Mohomed 2006). Just north of the Hondeklip Bay lighthouse a lesser-known bay is found, “Moordenaarsbaai”, where the study material that were used for describing the species was collected. Unfortunately, at that stage the authors could only spend one and a half day in the area, and no live material could be collected due to the neat tide and stormy seas. The recent trip to Hondeklip Bay by the authors did not disappoint, the tide timing was perfect with springtide and good weather. A bit of scratching between the rocks and sea grass in rough black-muddy sand revealed three live specimens. What makes this special is that this species so far only been found in this area and this is the first livematerial.

Assessment of potential toxic elements in soils, sediments, and vegetation in the surroundings of Anapa, Russia.

The study presented here reports the concentration of major, trace, and rare earth elements in soil, sediments, and vegetation samples collected from 13 locations around Anapa City located on the northern coast of the Black Sea in Russia. The neutron activation analysis technique has been used to fulfill this objective. Along with this, the bioconcentration and translocation factors were calculated. Overall, the content of 31 elements was detected in soil and sediments while 20 elements were determined in three types of vegetation: macroalgae (Cystoseira sp. and Ulva sp.), aquatic plants (Phragmites australis), and sea grass (Zostera sp.). The quantified concentration followed the order soil > sediment > vegetation. The phytotoxic levels for Zn, V, Mn, and Fe have been quantified as the highest. Bromine was the most abundant and accumulated in Phragmites australis. Based on the results obtained from this investigation, there is a possibility of contamination in the study area.

Microplastic pollution in aquafeed of diverse aquaculture animals

Microplastics have emerged as pervasive contaminants, and determining their occurrence in aquafeed is key for evaluating their risks to farmed animals and, by extension, humans. However, knowledge about microplastic in aquafeed is still limited. Herein, we determined microplastic characteristics in aquafeed for five important aquaculture animals with different feeding habits. Aquafeed samples were collected for spotted sea bass, shrimp, grass carp, Tilapia, and frogs from main companies in China. The samples were digested using chemical digestion, and the residuals were subjected to a density separation. Microplastics were identified under the microscope and characterized by their shape, color, size, and polymer type. The results showed that microplastics are highly abundant in the feed of frogs, followed by spotted sea bass, Tilapia, grass carp, and shrimp. We found that feed size contributes to the total microplastic abundance in the feed. Further, microplastics were mainly in microfiber form, and the dominant polymer type was propylene, suggesting that packaging and processing are the main sources of pollution. Additionally, the most abundant size of microplastics was 100–1000 μm. Calculating microplastic ingestion risk, the spotted sea bass had the greatest recorded risk of microplastic ingestion, followed by grass carp, frogs, Tilapia, and shrimp. This study lays a foundational step toward understanding microplastic effects on aquaculture animals and calls for further environmentally relevant laboratory experiments to assess the risk of microplastic ingestion on animals and potential transfer to humans.

In-vitro study of cytotoxic and apoptotic potential of Thalassia hemprichii (Ehren.) Asch. And Enhalus acoroides (L.f.) Royle against human breast cancer cell line (MCF-7) with correlation to their chemical profile

BackgroundBreast cancer is the most common type of cancer diagnosed in women. Finding novel therapeutic agents with significant cytotoxic action and minimal adverse impact on normal cells becomes crucial. Today, natural anticancer agents present an unconventional method of treating cancer, either as a curative or preventative agent, with considerable concern for marine organisms.MethodsThe anticancer effect of the alcoholic extract of different Red Sea Seagrasses on MCF-7 human breast cancer cell line has been investigated. Seagrasses were collected from Wadi El Gamal, Red Sea and extracted. Qualitative HPLC analysis was performed on the extracts for the identification of their active biomarkers. This study was aimed to explore the cytotoxic impact of Thalassia hemprichii (Ehren.) and Enhalus acoroides (L.f.) Royle on MCF-7 and their mode of action. Their anti-proliferative effects on cancer cells were performed using Neutral red assay. On the other hand, their apoptotic effect and their capacity to induce cell cycle arrest were investigated by flow cytometry assay. The effect of Seagrasses on the mitochondrial membrane potential (ΔψM) was studied by using JC-1 mitochondrial membrane potential assay kit in Seagrasses treated cancer cells to Δψ Caspases 3/7activity was examined using the colorimetric method. Gene expression analysis and quantitative real time RT-PCR for the sea grasses on MCF-7 was performed. Immune-blotting technique for Bcl-2 and p53 was investigated.ResultsHPLC analysis demonstrated that the extracts contained mainly flavonoids and polyphenols such as Caffeic acid, Chlorogenic acids, catechin and kaempferol that might be responsible for these anticancer effects. Seagrasses alcoholic crude extract markedly suppressed the growth and expansion of MCF-7 cells concentration-dependently with no toxicity against normal human skin fibroblast HSF. Thalassia hemprichii and Enhalus acoroides trigger mode of cell death primarily via apoptosis as confirmed by the flow cytometry. Additionally, they have ability to induce G0/S cell cycle arrest in MCF-7. The data showed the depletion in mitochondrial membrane potential (ΔψM) in the treated cells dose-dependently Caspases 3/7activities markedly increased following 24 h treatment. Finally, Gene expression analysis showed a marked reduction in Bcl-2, Survivin and CDC2 gene expression levels and a significant increase in the expression of p53 and CC2D1A as compared to control cells.ConclusionIn summary, the Methanolic extract of seagrass, Thalassia hemperchii and Enhalus ocoroides are able to induce concentration-dependent cytotoxic effects in human MCF-7 cells through intrinsic pathway of apoptosis in MCF-7 cells. This study reveals the beneficial importance of sea grasses as a source of anticancer agents. Further in vivo study is recommended for the active isolated biomolecules.

The state of the Ahnfeltia field and species composition of macrophytes in Izmena Bay of Kunashir Island (Southern Kuriles Islands)

Aim: the generalization of long-term results of a study of the Ahnfeltia formation and the species composition and distribution of the macrophytes in Izmena Bay (Kunashir Island).Method: data analysis was carried out on the basis of data obtained in 1989–2019 according on recommended methods of fisheries research.Novelty: data on the state of the Ahnfeltia formation and the species composition and distribution of macrophytes in Izmena Bay of Kunashir.Result: Since 2014, there has been a decrease in all parameters of the Ahnfeltia field: average layer height, biomass, total area and field reserve. The decline was particularly significant in 2019. The likely reason is fishing in the center of the field with fracturing against the backdrop of a general decline in the stock. In despit of a fairly significant species composition of macrophytes in the Izmena Bay, except for two species of sea grasses, in 1989–2019, most often, 3 types of algae are found — Chondrus armatus, Chorda asiatica and Chaetomorpha linum, which form settlements of varying densities. The general list of macrophytes found includes 79 species. Of these, more than 40 species are facultative epiphytes.Practical significance: The results will be used to make recommendations for the sustainable use of the commercial seaweed Ahnfeltia fastigiata var.tobuchiensis.

MINDORO OIL SPILL PROGRESS MONITORING USING SATELLITE IMAGERY

Abstract. Oil spills in the sea pose a significant threat to marine and coastal ecosystems including corals, sea grasses, and mangroves. Responding to oil spills in the high seas can be challenging and costly, as it is difficult to survey the area using ships or planes. Timely monitoring of extents and direction of drift is costly especially when large area is involved. This study used satellite imagery to monitor the progression of an oil spill in a timely manner. Images captured by various types of sensors was used to provide an almost daily oil extent map. Combining opensource satellite imagery, contributed imagery by commercial providers, and imagery from various national space agencies enabled situational awareness during the oil spill incident. Optical and SAR images were processed by using unsupervised K-means classification, for images that undergone image segmentation, and supervised support vector machine classification. The process was used to produce 46 oil extent maps from 196 satellite images from various sources through Sentinel Asia and The International Charter Space and Major Disasters.

A new shallow water species of the palaemonid shrimp genus Palaemon Weber, 1795 (Decapoda: Caridea) from Japan

During a survey of the shallow water decapod fauna in the Miura Peninsula, Kanagawa Prefecture, central Japan, four specimens of a new palaemonid shrimp, Palaemon parvibrachium n. sp., were collected from sea grass beds of Nanozostera japonica (Ascherson & Graebner) Tomlinson & Posluszny, 2001. The new species appears morphologically similar to P. serrifer (Stimpson, 1860), one of the most common representatives of Palaemon Weber, 1795 in Japanese waters, but the short carpus of the second pereopod and the different live colouration readily differentiate the new species from the latter. A DNA barcode (a partial fragment of the mitochondrial CO1 gene), as well as a partial fragment of the mitochondrial 16S rRNA gene, are provided to genetically characterize the new species.

Valuation of the Bar Reef Marine Sanctuary from the Perception of the Visitors


 
 
 Bar Reef is a diverse ecosystem with near shore coral reefs, sea grass beds and associated ecosystems with over 120 coral species and over 300 fish species reported from the surrounding sea. It has been declared as a marine sanctuary by the Department of Wildlife Conservation in 1992. Despite of the efforts it is subjected to over exploitation by extractive users, destructive fishing practices and visitor pressure on the ecosystem. The study sought to value the ecosystem degradation prevailing in the bar reef from the perception of the visitors using choice experiment method. Different attributes for the choice experiment were identified using two focus group discussions and 10 key informant interviews held prior to the mail survey. Identified attributes were level of plastic accumulated, use of illegal fishing nets, level of crowding and monetary contribution. An orthogonal main effect design was generated and 9 choice cards were prepared, each with 4 different attributes. Randomly selected 250 visitors were interviewed onsite during January to June 2021 and conditional logit model was used to analyze the significance of their preferences. Paying LKR 1,000, reducing crowding the beach area by 15% and reduction of plastic and polythene by 50% were the significant factors according to the results obtained at α=0.01. People are willing to pay LKR 1,001.18 if plastic pollution can be reduced by 50%. People are willing to pay LKR 998.92 if the crowding of the beach can be reduced by 15%. The results of this research emphasize the importance of protecting this habitat to the relevant stakeholders. Further, this research will enable to introduce new policies and practices so that sustainability of the ecosystem can be ensured.
 Keywords: Ecosystem sustainability, Choice experiment, Conditional logit, Marine plastic pollution, Visitor access management
 
 

Conservation of Coastal Agriculture and Forestry–towards a Sustainable Blue Economy

Blue economy is an economic system or sector that seeks to conserve marine and freshwater environments while using them in a sustainable way to develop economic growth and produce resources such as energy and food. In terms of the global economy, around 90 per cent of all internationally traded goods are shipped by sea, and the market value of marine and coastal resources and industries is estimated at US$3 trillion per year or about 5 per cent of global gross domestic product. Sustainable use of ocean, seas and marine resources, as set out in SDG14, lies at the center of a sustainable blue economy. Sri Lanka‘s coastline is 1,340 kilometres and approximately 33 percent of Sri Lanka's population lives in coastal areas that support diverse livelihoods, from fishing to tourism to manufacturing and modern urban services. The coastal areas often provide excellent soil and climatic conditions for agriculture, which has been practiced for thousands of years and plays an important role in the economy of coastal areas. Apart from the traditional rice based farming systems it also comprise of coastal fishing and coastal aquaculture, seaweed cultivation, coconut based cropping systems, commercial cash cropping systems and homestead farming systems. With regards to forests, mangroves, coastal forests, savannah woodlands, dry forests are present in these areas. Further, coral reefs, sea grass beds, salt marshes also play an important role in sustaining the balance as together they provide habitats for biodiversity, food, shade, medicine, products for the industry, protection of the coastline and carbon sequestration. However, these ecosystems are threatened due to numerous factors; climate change (as it induces flooding, shoreline erosion, salinity intrusion, temperature rise), due to conflicting activities such as operational in these coastal areas such as infrastructure including shoreline structures (harbors, breakwaters, tourist hotels), other tourism activities, industry etc. On the face of this, these ecosystems are often in the frontline to get depleted. The habitats are also getting modified due to the increase of toxicity from both inland and marine pollution, invasion of species. Therefore more concerted effort need to be exerted for the conservation and sustainable use of the oceans, seas and marine resources if the country wants to reap the benefits of the blue economy sustainably. As oceans are shared by many countries, actions need to be taken at country, region and even global levels in the areas of regulation, technology transfer, enhancing awareness and education. A mechanism for regular monitoring is a must and this responsibility need to be shared by all the stakeholders. It is imperative to zone the coastal areas so that complementary activities will be lumped together. It is also required to strengthen the already available international agreements between the member countries such as South Asian Seas Programme, Programmes with the International Maritime Organisations, IORA (Indian Ocean Rim Association), BIMSTECH in arriving at regional policies and action plans and implementation of same with proper monitoring. The quantification of the resource is a vital step. It is also important to operationalize the Coastal Zone Management Plans in existence and declare Special Area Management Sites to ensure conservation and sustainable use of these resources. 
 Keywords: Coastal agriculture, Forestry, Blue economy, Sustainable development goals, Management plans

Assessment of the Seasonal Potential of Macroalgae and Grass in the Sea of Azov for Methanogenesis and Optimization of the Digestate’s Carbon/Nitrogen Ratio

Large amounts of macroalgae and grass are dumped on the shores of the Sea of Azov in different seasons. Aquatic plant biomass management could contribute to sustainable development. By mixing them with co-substrates in an anaerobic bioreactor, not only can biogas be extracted, but suitable fertilizers can also be obtained. This study discusses the possibility of using methanogenesis waste from Azov Sea algae and sea grass as a fertilizer for agriculture. The main criterion is the presence of carbon (C) and nitrogen (N) in the waste products of methanogenesis. The influence of climatic and seasonal factors in the Azov region on the quality and quantity of storm emissions, on the productivity of methanogenesis, and changes in the ratio of carbon (C) and nitrogen (N) during methanogenesis and in the fermented substrate has been established. The influence of the ratio of the components of the mixture in various proportions, before methanogenesis, on the productivity of methanogenesis and the change in the ratio of carbon (C) and nitrogen (N) during the process of methanogenesis, and in the fermented substrate were studied. The biomass of the Sea of Azov, cattle manure and wastewater waste in various proportions, were used as components of the mixture. Recommendations are given for the selection of mixture components for methanogenesis, with predicted indicators of the ratio of carbon (C) and nitrogen (N) in the fermented substrate.

Benthic Habitat Classification Using Sentinel-2a Image With And Without Water Column Correction In Pengudang Village, Bintan Regency

Research on the mapping of benthic habitats in the waters of Pengudang Village, Bintan Regency, uses Sentinel-2A imagery. This mapping process has the potential to display the results of classification of benthic habitats in shallow waters. The purpose of this study was to assess the Maximum Likelihood Classification (MLH) algorithm model for mapping benthic habitat cover through Sentinel-2A satellite imagery using the lyzenga water column correction and without water column correction and to calculate the accuracy of the MLH classification results for benthic habitats in waters Pengudang Village. This classification uses a pixel-based image classification which is grouped into a cover class for each pixel. This classification groups into 4 benthic habitat classes, namely dead coral sand (KMP), sea grass (LM), live coral sand (PKH) and sand (PS). The results showed that the application of the lyzenga correction using the MLH algorithm in mapping benthic habitats resulted in a significant accuracy rate (80,00%), while the application without lyzenga correction using the MLH algorithm resulted in an accuracy rate (76,00%). These findings support the use of the lyzenga correction method which can increase the level of accuracy by (4,00%) with the MLH algorithm as a guide in better mapping of benthic habitat cover in Pengudang Village.

Geographical characteristics that promote persistence and accumulation of PFAS in coastal waters and open seas: Current and emerging hot spots

Poly- and perfluoalkyl substances (PFAS) have been found in ocean water, sediments, and marine organisms. The objective of this study was to identify coastal and open water conditions that affect accumulation and transport characteristics of PFAS in coastal areas and open waters. Coastal conditions were compared based on the classification for Shoreline Cleanup and Assessment Technique (SCAT). Open sea conditions were evaluated in relation to ocean currents. PFAS data available in the literature from different coastal areas and open seas were compiled. Tidal flats, sheltered shores, salt and brackish marshes, bays and estuaries, mangroves, and areas with coral reefs, sea grasses, kelp have conditions that are favorable for PFAS accumulation and ecosystems in these environments are vulnerable to long term PFAS exposure and bioaccumulation. The areas near the centers of gyres in oceans trap and accumulate floating debris as well as PFAS contaminated particles. PFAS accumulation in highly productive coastal areas with mangrove forests, seagrasses and salt marshes can affect the ecosystems in these locations. PFAS data from marine environments indicate that some areas in the Indian Ocean (41.1 ng/L), North Pacific Ocean (12.8 ng/L), and North Atlantic Ocean (4.0 ng/L) relatively high levels of PFAS. Marine organisms with long life spans are likely to accumulate high levels of PFAS over their lifespan. PFAS concentrations at vulnerable coastal waters and open seas should be monitored systematically and periodically to establish the baseline conditions and evaluate the changes in PFAS levels water column and sediments overtime.

ВОДНЫЕ РАСТЕНИЯ ПРИБРЕЖНОЙ ЗОНЫ КАСПИЙСКОГО МОРЯ И ИХ ПРАКТИЧЕСКОЕ ПРИМЕНЕНИЕ

Seagrasses of the Zosteraseae family are a valuable biological resource and raw material used for the production of zosterol, a polysaccharide of pectic nature, since the early 40-s of the XX century. Currently, the volumes of Zostera reserves in the Caspian Sea have not been sufficiently studied. The places of mass growth of Zostera, as well as the places of mass accumulation of storm emissions of Zostera formed after seasonal storm winds, remain unknown. The presented research results are devoted to determining the species composition of aquatic vegetation in the coastal zone of the Caspian Sea, as well as the problem of collecting and storing storm emissions of the sea grass Nanozostera noltei. The coast of the Caspian Sea with a length of about 150 km from the Agrakhan Bay to the city of Izberbash was explored. Dominant species of aquatic plants were found: Ruppia maritima, Ceratophyllum demersum, Laurencia caspica, Cladophora, storm surges of N. noltei. Technological instructions for the collection and preparation of dried sea grass of the Zosteraseae family have been developed. It was revealed that Nanozostera and Laurencia are of particular practical interest.

Economical and eco‐friendly adsorbent derived from “Halodule uninervis” for effective removal of N‐nitrosodiphenylamine from wastewater: Equilibrium, reusability, and mechanism studies

AbstractN‐nitrosodiphenylamine (NDPhA) is soluble in water and highly toxic. Exposure to NDPhA even at low concentrations for a long period can cause several health effects. Hence the removal of NDPhA from aqueous samples using a widely abundant and economical adsorbent is highly challenging. In this study, a highly efficient, eco‐friendly, and low‐cost adsorbent was derived from the dead leaves of Halodule uninervis seagrass (SG) without any chemical modifications. The derived adsorbent was characterized and investigated for the removal of NDPhA from aqueous solutions. The effects of solution pH, contact time, adsorbent dosage, and adsorbate concentration were studied and optimized. The SG adsorbent showed a significant removal efficiency of 83% for NDPhA from wastewater solution using 1 g L−1 adsorbent. The maximum adsorption capacity for SG was found to be 64.84 mg g−1 at neutral pH and room temperature. The adsorption isotherm results fitted with the Langmuir model and followed pseudo‐second‐order kinetics. From the thermodynamic parameters, it has been found that the adsorption of NDPhA onto SG adsorbent is favorable, endothermic, and the chemical adsorption mechanism is predominant. This study indicated that SG adsorbent is reusable and can be easily regenerated and reused at least three times with a slight decrease in its removal efficiency.

Treatment and recovery of phosphate from submerged anaerobic membrane bioreactor effluent using thermally treated biowaste and powder activated carbon

This study presents a novel treatment system using a submerged anaerobic membrane bioreactor (SAnMBR) followed by adsorption onto thermally treated biowaste, and ending with a final treatment using powdered activated carbon (PAC). Despite limited phosphate and ammonium ion removal during SAnMBR operation, thermally treated eggshell (EGSL) and seagrass (SG) received SAnMBR effluent and enhanced phosphate recovery, achieving removal rates of 71.8–99.9% and 60.5–78.0%, respectively. The SAnMBR achieved an 85% COD removal, which was slightly reduced further by biowaste treatment. However, significant further reductions in COD to 20.2 ± 5.2 mg/L for EGSL effluent and 57.0 ± 13.3 mg/L for SG effluent were achieved with PAC. Phytotoxicity tests showed the SAnMBR effluent after PAC treatment notably improved seed growth compared to untreated wastewater. In addition, volatile organic compounds (VOCs) were significantly reduced in the system, including common wastewater contaminants such as dimethyl disulfide, dimethyl trisulfide, phenol, p-cresol, nonanal, and decanal. Fractionation analysis of the solid fraction, post-adsorption from both synthetic and domestic wastewater, indicated that for SG, 77.3%–94% of the total phosphorus (TP) was inorganically bound, while for EGSL, it ranged from 94% to 95.3%. This study represents the first attempt at a proof-of-concept for simultaneous treatment of domestic wastewater and phosphorus recovery using this integrated system.

INVESTIGATION OF PROBIOTICS-SORPTION PROPERTIES OF THE COMPOSITION BASED ON POMACE

The use of enterosorbents to relieve intoxication and to increase the content of prebiotics in the body is a topical problem of every second metropolis resident. The pharmaceutical market offers a huge number of enterosorbents, some of which can cause negative consequences (for example, mechanical damage, constipation etc.). The others that are more compatible with the body, for example, pectins, are expensive due to the energy-intensive process of their isolation. We offer a preparation based on pomace powder (60%) with the addition of starch, kaolin and pectin from sea grass eelgrass (Zostera marina) (6%). The powder is obtained by a previously developed and patented method and has an established sufficiently high sorption activity. At the same time, apple pomace also contains pectin, which is a substrate for the growth of beneficial microorganisms living in the colon.
 The article presents the data of a comparative analysis of the sorption activity of the developed powder and a number of enterosorbents offered by the pharmaceutical market in relation to standard test substances: methylene blue and pharmaceutical gelatin. It is shown that the composite enterosorbent obtains effective sorption properties and equals to common sorbents. When dissolved in water, the powder acquires a gel-like consistency that gives it additional therapeutic and preventive properties. The use of apple pomace as a basis enables to reduce the cost of producing expensive pectin and make it more affordable for the population.

The Density of Anadara granosa in Tin Mining Area at Tanjung Gunung Seawaters, Bangka Island

Tin mining activity has been for quite some time existed in Bangka Belitung, directed lawfully and wrongfully. In the first place, the tin mining activity happens just in the mainland however at this point has been extended to the coastal zone. As the effect, supporting ecosystems such as coral reefs, sea grasses, marine biotas, and mangrove ecosystem cannot play their role normally especially in Tanjung Gunung Waters, Central Bangka. One of biota living at coastal zone in tin mining area is a Anadara granosa. Blood clam (A. granosa) is a type of shellfish that has important economic value and has the potential to become one of the leading marine fisheries products. The research method used is purposive sampling with systematic random sampling. The result showed that the density of A. granosa was low abundant each stasions at Tanjung Gunung. Total Organic Carbon range 1,03 – 5,57%. Sand (80%), Silt (11,65%), Clay (8,35%). Based on the analysis, density of A. granosa has the correlation with sedimen type and water quality (Dissolved oxygen, Salinity, Temperatur, EH).

Measuring Job Satisfaction and Work-Life Balance at Foam Mattings India Ltd., Kerala

A company's human resources division oversees all matters involving employees. The HR department also keeps up with any new laws dictating how employees should be treated during the hiring, working, and firing processes. A venture of the Kerala government is Foam Mattings India Limited. Fomil offers a variety of products, including mats, door mats, rugs, carpets, car mats, coir tiles, Coir Geo-Textiles, and a number of other environmentally friendly items, to meet the needs of both domestic and foreign markets. Their guiding principle is eco-friendliness, so all of their items are manufactured entirely of natural materials like coir, jute, sisal, cotton, sea grass, flax, paper, and hemp. Over 200 highly competent employees with specialized training are employed in the manufacturing facility in order to guarantee that each and every product that departs is flawless. The paper seeks to assess the quality of work life among the enterprise's employees. A sample of 25 employees was collected for the same purpose. The case study aims to shed light on work quality in the organizational context.

Counting manatee aggregations using deep neural networks and Anisotropic Gaussian Kernel

Manatees are aquatic mammals with voracious appetites. They rely on sea grass as the main food source, and often spend up to eight hours a day grazing. They move slow and frequently stay in groups (i.e. aggregations) in shallow water to search for food, making them vulnerable to environment change and other risks. Accurate counting manatee aggregations within a region is not only biologically meaningful in observing their habit, but also crucial for designing safety rules for boaters, divers, etc., as well as scheduling nursing, intervention, and other plans. In this paper, we propose a deep learning based crowd counting approach to automatically count number of manatees within a region, by using low quality images as input. Because manatees have unique shape and they often stay in shallow water in groups, water surface reflection, occlusion, camouflage etc. making it difficult to accurately count manatee numbers. To address the challenges, we propose to use Anisotropic Gaussian Kernel (AGK), with tunable rotation and variances, to ensure that density functions can maximally capture shapes of individual manatees in different aggregations. After that, we apply AGK kernel to different types of deep neural networks primarily designed for crowd counting, including VGG, SANet, Congested Scene Recognition network (CSRNet), MARUNet etc. to learn manatee densities and calculate number of manatees in the scene. By using generic low quality images extracted from surveillance videos, our experiment results and comparison show that AGK kernel based manatee counting achieves minimum Mean Absolute Error (MAE) and Root Mean Square Error (RMSE). The proposed method works particularly well for counting manatee aggregations in environments with complex background.

Isolation and molecular detection of endophytic actinomycetes Nocardiopsis dassonvillei DMS 1 (MH900216) from marine sea grasses with bacterial inactivation

In recent years, new antibiotics have been discovered around the world in order to inhibit multi-drug resistant (MDR) pathogens. To overcome this problem, marine actinomycetes are an alternative choice for producing new bioactive compounds that inhibit MDR bacteria. The typical endophytic actinomycete (EA) Nocardiopsis dassonvillei (N. dassonvillei) DMS 1 (MH900216) was isolated from marine Sea grasses by surface sterilization method. After surface sterilization, it was confirmed that the pure, dry, white-colored spore producing colonies emerged from the internal tissue of the Sea grasses. The crude extract of N. dassonvillei DMS 1 (MH900216) demonstrated 8- and 10-mm zones of inhibition against A. baumannii and K. pneumoniae, respectively. The composition of N. dassonvillei DMS 1 (MH900216) with potential anti-bacterial properties was studied by GC-MS analysis and exhibited 22 chemical compounds. Subsequently, the molecular identification and phylogenetic construction of the isolated EA strain was confirmed as N. dassonvillei DMS 1 (MH900216). The liquid-liquid extraction of the compound demonstrated 24- and 26-mm zones of inhibition against A. baumannii and K. pneumoniae, respectively. Furthermore, the purified crude compound demonstrated 92% and 94% cell death against A. baumannii and K. pneumoniae, respectively, at a minimum inhibitory concentration of 500 μg/mL. Overall, the present study demonstrated the antibacterial properties of the EA N. dassonvillei DMS 1 (MH900216) isolated from Sea grasses and their importance as alternative sources for discovering new antibiotics to inhibit MDR bacteria.