Effect of dissolved oxygen deficiency on 210Pb content in mussel's tissues at the Johor strait, Malaysia

Aim: To investigate the effect of dissolved oxygen deficiency on the level of 210Pb in mussel's tissues, Perna viridis which has been reported to be highly tolerant to hypoxia. Methodology: Mussels (Perna viridis), seawater and sediment samples were collected from nine stations along the Johor Straits during North-east monsoon (November 2017), inter-monsoon (March 2018), and South-west monsoon (August 2018). The 210Pb contents were extracted and estimated by Gross Alpha-beta Counter. Results: The lowest dissolved oxygen was recorded at Station 4 which decreased from 2.14 mg l-1 to 2.10 mg l-1 and subsequently to 1.63 mg l-1 during first to third samplings. In sediment, 210Pb activities increased with the increase in organic matter. Meanwhile, in mussels, the 210Pb activities showed almost similar trend with sediment where 210Pb activities were much higher adjacent to the causeway structure, especially at the East part of Johor Strait. The level of 210Pb in mussel's tissue and sediment also increased with decreasing level of dissolved oxygen. Interpretation: A causeway structure disrupted the water quality of Johor Straits and caused almost hypoxic conditions nearby. The coverage of oxygen depletion expanded during inter-monsoon. An inverse relationship between 210Pb activities and dissolved oxygen prove that deficiency of dissolved oxygen potentially influenced the bioaccumulation of 210Pb in mussels to correspond to the build-up of concentration factor in their tissues which exceeded the recommended value.

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Fewer Copepods, Fewer Anchovies, and More Jellyfish: How Does Hypoxia Impact the Chesapeake Bay Zooplankton Community?

Diversity ◽

10.3390/d12010035 ◽

2020 ◽

Vol 12 (1) ◽

pp. 35

Author(s):

Wencheng L. Slater ◽

James J. Pierson ◽

Mary Beth Decker ◽

Edward D. Houde ◽

Carlos Lozano ◽

...

Keyword(s):

Dissolved Oxygen ◽

Chesapeake Bay ◽

Oxygen Deficiency ◽

Principal Component ◽

Gelatinous Zooplankton ◽

Planktivorous Fish ◽

Crustacean Zooplankton ◽

Mnemiopsis Leidyi ◽

Hypoxic Conditions ◽

Temperature Group

To understand dissolved oxygen deficiency in Chesapeake Bay and its direct impact on zooplankton and planktivorous fish communities, six research cruises were conducted at two sites in the Chesapeake Bay from spring to autumn in 2010 and 2011. Temperature, salinity, and dissolved oxygen were measured from hourly conductivity, temperature, and depth (CTD) casts, and crustacean zooplankton, planktivorous fish and gelatinous zooplankton were collected with nets and trawls. CTD data were grouped into three temperature groups and two dissolved oxygen-level subgroups using principal component analysis (PCA). Species concentrations and copepod nonpredatory mortalities were compared between oxygenated conditions within each temperature group. Under hypoxic conditions, there usually were significantly fewer copepods Acartia tonsa and bay anchovies Anchoa mitchilli, but more bay nettles Chyrsaora chesapeakei and lobate ctenophores Mnemiopsis leidyi. Neutral red staining of copepod samples confirmed that copepod nonpredatory mortalities were higher under hypoxic conditions than under normoxia, indicating that the sudden decline in copepod concentration in summer was directly associated with hypoxia. Because comparisons were made within each temperature group, the effects of temperature were isolated, and hypoxia was clearly shown to have contributed to copepod decreases, planktivorous fish decreases, and gelatinous zooplankton increases. This research quantified the direct effects of hypoxia and explained the interactions between seasonality and hypoxia on the zooplankton population.

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Impact of Climate Condition on Flowering, Fruiting, Kernel and Nut-yield In Newly Added Potential Growing Areas of Cashewnut in India- A Review

International Journal of Advances in Agricultural Science and Technology ◽

10.47856/ijaast.2021.v08i3.003 ◽

2021 ◽

Vol 8 (3) ◽

pp. 27-39

Author(s):

Heli S. Oza ◽

Hitesh Solanki

Keyword(s):

Tamil Nadu ◽

Kernel Weight ◽

Nicobar Island ◽

North East ◽

Cashew Nut ◽

Yield And Quality ◽

South West Monsoon ◽

Good Potential ◽

Good Scale

Cashew is now an important Horticulture plant for India and now India is exporting cashew at a good scale. Traditional Indian growing area comprises the parts of Karnataka, Maharashtra, Goa, West Bengal, Odisha, Andhra Pradesh and Tamil Nadu states. However, now new areas are coming up with good potential for cultivation such as Gujarat, Jharkhand, Chhattisgarh, Andaman and Nicobar island, North Earsten Hilly States. Cashew cultivars are recommended based on geographical distribution, climate, soil based on these flowering and fruiting time. Cashew nut yield and kernel weight can be different for different varieties and so on its quality with shelling can vary. Flowering and fruiting is greatly influenced by rain because it starts flowering after monsoon, which is greatly influenced by the onset and offset of Indian monsoon that India varies from state to state as India has north-east monsoon and south-west monsoon. Moreover, soil characteristics across India varies widely. Integrated effect of soil, rainfall and temperature drives the optimum growth of cashew trees, which resulted in the change in yield and quality of cashew nuts. The present review paper addresses many of these drivers and their impact on cashew produce in India.

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The impact of self-reported oral health on the quality of life of teenage students with or without orthodontic treatment from North-East of Romania

10.15303/rjeap.2016.si1.a44 ◽

2016 ◽

Author(s):

GEORGETA ZEGAN ◽

◽

CRISTINA GENA DASCĂLU ◽

RADU EDUARD CERNEI ◽

RADU BOGDAN MAVRU ◽

...

Keyword(s):

Quality Of Life ◽

Oral Health ◽

Orthodontic Treatment ◽

North East ◽

The Impact

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A New Life for the St. Croix River

Water Quality Research Journal ◽

10.2166/wqrj.1988.044 ◽

1988 ◽

Vol 23 (4) ◽

pp. 568-577

Author(s):

Harold S. Bailey

Keyword(s):

Water Quality ◽

Dissolved Oxygen ◽

Discharge Rate ◽

Paper Mill ◽

Regulated River ◽

Secondary Treatment ◽

Pulp And Paper Mill ◽

Oxygen Regime ◽

Oxygen Concentrations

Abstract The water quality of the upper 110 kilometres of the St. Croix River is considered to be pristine. A major industrial discharge renders the lower 14 kilometres of the river a water quality limited segment. Prior to 1970 the Georgia-Pacific Pulp and Paper Mill at Woodland, Maine, discharged untreated effluent directly into the river causing dissolved oxygen concentrations to drop well below 5 mg/L, the objective chosen in the interest of restoring endemic fish populations. Since 1972, the Mill has installed primary and secondary treatment, regulated river discharge rate and effluent composition which has greatly improved the summer dissolved oxygen regime. By 1980, dissolved oxygen concentrations were generally above 5.0 mg/L and restocking the river with Atlantic Salmon (Salmo salar) was initiated.

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Investigation of the Contribution of Natural Organic Runoff to Dissolved Oxygen Depletion in the Red Deer River

Water Quality Research Journal ◽

10.2166/wqrj.1979.007 ◽

1979 ◽

Vol 14 (1) ◽

pp. 71-88

Author(s):

S.E. Penttinen ◽

P.H. Bouthillier ◽

S.E. Hrudey

Keyword(s):

Dissolved Oxygen ◽

Red Deer ◽

Stream Water ◽

Oxygen Demand ◽

Oxygen Depletion ◽

Experimental Program ◽

Nitrogen Budgets ◽

Carbon And Nitrogen ◽

Tributary Stream ◽

Small Tributary

Abstract Studies on the chronic low dissolved oxygen problems encountered under winter ice in the Red Deer River have generally been unable to account for dissolved oxygen depletion in terms of known manmade inputs. An experimental program was developed to assess the possible nature and approximate bounds of oxygen demand due to natural organic runoff carried to the Red Deer River by a small tributary stream, the Blindman River. The study employed an electrolytic respirometer on stream water samples subjected to prior concentration by vacuum evaporation. Evaluation of carbon and nitrogen budgets in conjunction with the measured oxygen demand indicate that biochemical oxygen demand is originating with natural organic runoff in tributaries of the Red Deer River. The results provide a basis for estimation of the possible contribution to the observed oxygen demand in the Red Deer River originating from natural organic runoff.

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Effect of 3-Aminobenzoic Acid Ethyl Ester Methanesulfonate (MS-222) on Quality of Marine Cultured Turbot (Scophthalmus maximus) during Simulated Transport in Water

Fishes ◽

10.3390/fishes6020020 ◽

2021 ◽

Vol 6 (2) ◽

pp. 20

Author(s):

Jie Cao ◽

Qi Wang ◽

Jun Mei ◽

Jing Xie

Keyword(s):

Dissolved Oxygen ◽

Ethyl Ester ◽

Acid Ethyl Ester ◽

Scophthalmus Maximus ◽

Ammonia Nitrogen ◽

Control Group ◽

Aminobenzoic Acid ◽

Transport Stress ◽

Turbot Scophthalmus Maximus

This study evaluated the effect of different concentrations (20, 40 and 60 mg/L) of 3-aminobenzoic acid ethyl ester methanesulfonate (MS-222) on the quality changes in turbot during simulated transport in water. The results showed that the ammonia nitrogen content in the transportation water of each sample increased significantly, and the dissolved oxygen level decreased. The dissolved oxygen content in MS-222-treated samples was higher than that of control group (CK) samples. For turbot flesh quality, simulated transport in water led to a decrease in moisture, fat and protein contents in all samples. The MS-222-treated turbot samples showed higher pH values, glycogen contents, springiness and chewiness values and lower lactic acid contents comparing with the CK samples during simulated transport in water. In addition, the fresh and bitter amino acids in the muscle of turbot increased in each treatment group compared to the non-transported fish at the end of the simulated transport. The results showed that MS-222 treatment could retard the turbot transport stress and improve the quality of turbot during simulated transport in water.

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Perceived quality of care among people with type 2 diabetes mellitus in the north east region of peninsular Malaysia

BMC Public Health ◽

10.1186/s12889-021-10320-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Noorfariza Nordin ◽

Suhaily Mohd Hairon ◽

Najib Majdi Yaacob ◽

Anees Abdul Hamid ◽

Seoparjoo Azmel Mohd Isa ◽

...

Keyword(s):

Quality Of Care ◽

Perceived Quality ◽

Peninsular Malaysia ◽

North East ◽

The North ◽

East Region ◽

Perceived Quality Of Care ◽

Significant Difference

Abstract Background People with type 2 diabetes mellitus (T2DM) are best managed by a chronic care model that is associated with enhanced quality of care and improved patient outcome. Assessing patients’ perceived quality of care is crucial in improving the healthcare delivery system. Hence, this study determined the perceived quality of care among people with T2DM and explored its associations with (i) sociodemographic and clinical characteristics and (ii) types of healthcare clinics to guide future planning. Methods A cross-sectional study involving 20 primary healthcare clinics in the North East Region of Peninsular Malaysia and people with T2DM as the sampling unit was conducted from February to May 2019. The pro forma checklist, interview-guided Skala Kepuasan Interaksi Perubatan-11, and Patient Assessment of Chronic Illness Care (Malay version; PACIC-M) questionnaire were used for data collection. Univariate analysis and linear regression were used to determine the status of perceived quality of care and the factors associated with the perceived quality of care, respectively. Results Overall, data from 772 participants were analyzed. The majority was from the Malay ethnic group (95.6%) with a mean (standard deviation [SD]) glycated hemoglobin A1c (HbA1c) level of 8.91% (2.30). The median (interquartile range [IQR]) of the number of medical officers available at each clinic was 6 (7), with Family Doctor Concept (FDC) clinics having a higher number of medical officers than non-FDC clinics (p = 0.001). The overall mean (SD) PACIC-M score was 2.65 (0.54) with no significant difference between scores of patients treated in the two clinic types (p = 0.806). Higher perceived quality of care was associated with lower number of medical officers (adjusted regression coefficient [Adj.β], − 0.021; p-value [p], 0.001), and greater doctor–patient interaction in all domains: distress relief (Adj.β, 0.033; p, < 0.001), rapport (Adj.β, 0.056; p, < 0.001), and interaction outcome (Adj.β, 0.022; p, 0.003). Conclusion Although there was no significant difference found between clinic type, this study reflects that patients are comfortable when managed by the same doctor, which may support a better doctor-patient interaction. A larger specialized primary care workforce could improve diabetes care in Malaysia.

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Patterns, Trends and Drivers of Water Transparency in Sri Lanka Using Landsat 8 Observations and Google Earth Engine

Remote Sensing ◽

10.3390/rs13112193 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2193

Author(s):

Deepakrishna Somasundaram ◽

Fangfang Zhang ◽

Sisira Ediriweera ◽

Shenglei Wang ◽

Ziyao Yin ◽

...

Keyword(s):

Sri Lanka ◽

Human Activity ◽

Google Earth ◽

Water Transparency ◽

Conservation Strategies ◽

Landsat 8 ◽

Essential Information ◽

Annual Variations ◽

North East ◽

South West Monsoon

Addressing inland water transparency and driver effects to ensure the sustainability and provision of good quality water in Sri Lanka has been a timely prerequisite, especially under the Sustainable Development Goals 2030 agenda. Natural and anthropogenic changes lead to significant variations in water quality in the country. Therefore, an urgent need has emerged to understand the variability, spatiotemporal patterns, changing trends and impact of drivers on transparency, which are unclear to date. This study used all available Landsat 8 images from 2013 to 2020 and a quasi-analytical approach to assess the spatiotemporal Secchi disk depth (ZSD) variability of 550 reservoirs and its relationship with natural (precipitation, wind and temperature) and anthropogenic (human activity and population density) drivers. ZSD varied from 9.68 cm to 199.47 with an average of 64.71 cm and 93% of reservoirs had transparency below 100 cm. Overall, slightly increasing trends were shown in the annual mean ZSD. Notable intra-annual variations were also indicating the highest and lowest ZSD during the north-east monsoon and south-west monsoon, respectively. The highest ZSD was found in wet zone reservoirs, while dry zone showed the least. All of the drivers were significantly affecting the water transparency in the entire island. The combined impact of natural factors on ZSD changes was more significant (77.70%) than anthropogenic variables, whereas, specifically, human activity accounted for the highest variability across all climatic zones. The findings of this study provide the first comprehensive estimation of the ZSD of entire reservoirs and driver contribution and also provides essential information for future sustainable water management and conservation strategies.

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Citizen Science Tools Reveal Changes in Estuarine Water Quality Following Demolition of Buildings

Remote Sensing ◽

10.3390/rs13091683 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1683

Author(s):

Nandini Menon ◽

Grinson George ◽

Rajamohananpillai Ranith ◽

Velakandy Sajin ◽

Shreya Murali ◽

...

Keyword(s):

Water Quality ◽

Dissolved Oxygen ◽

Citizen Science ◽

Secchi Depth ◽

Lake Water Quality ◽

Demolition Waste ◽

Water Colour ◽

Water Quality Variables ◽

The Impact

Turbidity and water colour are two easily measurable properties used to monitor pollution. Here, we highlight the utility of a low-cost device—3D printed, hand-held Mini Secchi disk (3DMSD) with Forel-Ule (FU) colour scale sticker on its outer casing—in combination with a mobile phone application (‘TurbAqua’) that was provided to laymen for assessing the water quality of a shallow lake region after demolition of four high-rise buildings on the shores of the lake. The demolition of the buildings in January 2020 on the banks of a tropical estuary—Vembanad Lake (a Ramsar site) in southern India—for violation of Indian Coastal Regulation Zone norms created public uproar, owing to the consequences of subsequent air and water pollution. Measurements of Secchi depth and water colour using the 3DMSD along with measurements of other important water quality variables such as temperature, salinity, pH, and dissolved oxygen (DO) using portable instruments were taken for a duration of five weeks after the demolition to assess the changes in water quality. Paired t-test analyses of variations in water quality variables between the second week of demolition and consecutive weeks up to the fifth week showed that there were significant increases in pH, dissolved oxygen, and Secchi depth over time, i.e., the impact of demolition waste on the Vembanad Lake water quality was found to be relatively short-lived, with water clarity, colour, and DO returning to levels typical of that period of year within 4–5 weeks. With increasing duration after demolition, there was a general decrease in the FU colour index to 17 at most stations, but it did not drop to 15 or below, i.e., towards green or blue colour indicating clearer waters, during the sampling period. There was no significant change in salinity from the second week to the fifth week after demolition, suggesting little influence of other factors (e.g., precipitation or changes in tidal currents) on the inferred impact of demolition waste. Comparison with pre-demolition conditions in the previous year (2019) showed that the relative changes in DO, Secchi depth, and pH were very high in 2020, clearly depicting the impact of demolition waste on the water quality of the lake. Match-ups of the turbidity of the water column immediately before and after the demolition using Sentinel 2 data were in good agreement with the in situ data collected. Our study highlights the power of citizen science tools in monitoring lakes and managing water resources and articulates how these activities provide support to Sustainable Development Goal (SDG) targets on Health (Goal 3), Water quality (Goal 6), and Life under the water (Goal 14).

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Hypoxic tolerance of Chinese black sleeper Bostrichthys sinensis embryos at heartbeat stage

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315406014548 ◽

2006 ◽

Vol 86 (6) ◽

pp. 1473-1476 ◽

Cited By ~ 1

Author(s):

Shixi Chen ◽

Wanshu Hong ◽

Wei Zhou ◽

Qiyong Zhang

Keyword(s):

Dissolved Oxygen ◽

Exposure Time ◽

Hypoxic Conditions ◽

Hypoxic Tolerance ◽

Heartbeat Rate ◽

Bostrichthys Sinensis ◽

Oxygen Concentrations

Tolerance of hypoxia in Chinese black sleeper (Bostrichthys sinensis) embryos at heartbeat stage was examined at different oxygen concentrations. Embryonic response to hypoxic conditions was expressed in terms of the intensity of variation in heartbeat rate (V). Exposure of the embryos at 25°C to 0.5, 1.0 and 1.5 mg/l dissolved oxygen (DO), caused bradycardia, which was developed within the first 10 min of hypoxia, followed by a plateau, and lasted until termination of the hypoxia. The V values were significantly affected by DO concentrations (P<0.01). Exposure of the embryos to 0.2 mg/l DO at 25°C caused a periodic heartbeat (including a period of heartbeat and a period of silence). This phenomenon was first recorded in the present study. During the period of heartbeat, the heartbeat rates were faster at first (147±5 beats per min), and then decreased gradually until the period of silence. As the exposure time increased, the duration of heartbeat was prolonged significantly from 43.4±2.4 second to 126.2±8.2 second (P<0.01), and the duration of silence was also prolonged significantly from 68.0±5.5 second to 247.9±11.5 second (P<0.01). At the beginning of exposure, the primary heartbeat rates displayed tachycardia, and their V values were significantly lower than the V values of average heartbeat rates (P<0.05). However, the V values were not significantly different between primary heartbeat rate and average heartbeat rate after 90 min exposure (P>0.05).

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