Characteristics of primary production in a eutrophicated bay

2001 ◽  
Vol 43 (5) ◽  
pp. 269-276 ◽  
Author(s):  
M. Nakashima ◽  
I.-C. Lee ◽  
T. Kusuda
Keyword(s):  
Water Quality ◽  
Primary Production ◽  
Winter Season ◽  
Biological Response ◽  
High Growth ◽  
Ecosystem Model ◽  
Organic Pollution ◽  
Ambient Conditions ◽  
High Concentration ◽  
Study Characteristics

The primary production of phytoplanktons provides organic matter in high concentration in eutrophicated Hakata bay in Japan, even during the winter season in spite of low water temperature. Phytoplanktons may have the biological capabilities to maintain activities of photosynthesis under unfavorable conditions, and these capabilities affect water quality in the bays. In this study, characteristics of primary production were analyzed with a simple box-type ecosystem model. We introduced a concept of efficiency for absorption of sunlight energy to our simulation model of water quality to explain rather high growth rates of phytoplanktons in low sunlight intensity. Through simulation with a box model, we found that the efficiency of primary production in winter is higher than that in summer. It was suggested that the organic pollution comes from dissolved organic carbon (DOC) throughout the year and that the DOC is originated from the primary production of phytoplanktons in biological response of the seasonal change of ambient conditions.

scholarly journals Multivariate Statistical Application for the Assessment of Surface Water Quality in Lower Zab River, Kirkuk

2020 ◽  
Vol 16 ◽  
Keyword(s):  
Water Quality ◽  
Winter Season ◽  
Oxygen Demand ◽  
Principal Component ◽  
Total Variance ◽  
Data Matrix ◽  
Total Hardness ◽  
High Concentration ◽  
Multivariate Statistical ◽  
High Positive Correlation

Spatiotemporal variation analysis of water quality in the river is very vital for water resources protection and sustainable consumption. In this study, Multivariate statistical methods, i.e., Principal Component Analysis (PCA), Canonical Correlation Analysis (CCA) and Multi Recreation Analysis (MRA) were used to interpret of data matrix in water quality over a period of five years (2015–2019) in the Lower Zab River. The results from PCA matrix showed high positive correlation between total hardness and sulphate (SO4) at 95% confidence level (0.934) indicating that non-carbonate hardness is a measure in the river. By using Varimax rotation and by extracting the eigenvalues greater than 1 from the correlation matrix, number of significant principal components (PCs) were extracted. Five and four latent factors respectively in Lower Zab station 3 (LZ3) and Lower Zab station 2 (LZ2) were identified as responsible for the data structure, explaining 86.8% of total variance in winter season in LZ3 station and it is strong positive related to the SO4, nitrate (NO3), chloride (CL) and pH. All these variables are related to the weathering of minerals component of the river. 87.5% of total variance for winter season in LZ2 station, which is strongly positive, related to the NO3, pH, sodium (NA) and magnesium (MG) related to the weathering of minerals component. The strong correlations between PC3 and five-day biochemical oxygen demand (BOD5) as a result of CCA in LZ3 station during summer season, indicates that the high concentration of calcium (CA) and dissolved oxygen (DO) in water cause the low concentration of BOD5. Among 72 multiple regression model run, only eight dependent variables had statistically significant relationships with independent variables. These results provide may useful information for water quality in the Lower Zab River, which can mainly affected by weathering of minerals component of the river, soil structure and run-off.

MEASURES FOR ENVIRONMENT CONSERVATION IN ENCLOSED COASTAL SEAS

2017 ◽  
Author(s):  
Keizo Negi ◽  
Keizo Negi ◽  
Takuya Ishikawa ◽  
Takuya Ishikawa ◽  
Kenichiro Iba ◽  
...  
Keyword(s):  
Water Pollution ◽  
Water Quality ◽  
Water Mass ◽  
Sea Water ◽  
Red Tide ◽  
Water Environment ◽  
Quality Standard ◽  
Tokyo Bay ◽  
View Point ◽  
High Concentration

Japan experienced serious water pollution during the period of high economic growth in 1960s. It was also the period that we had such damages to human health, fishery and living conditions due to red tide as much of chemicals, organic materials and the like flowing into the seas along the growing population and industries in the coastal areas. Notable in those days was the issues of environment conservation in the enclosed coastal seas where pollutants were prone to accumulate inside due to low level of water circulation, resulting in the issues including red tide and oxygen-deficient water mass. In responding to these issues, we implemented countermeasures like effluent control with the Water Pollution Control Law and improvement/expansion of sewage facilities. In the extensive enclosed coastal seas of Tokyo Bay, Ise Bay and the Seto Inland Sea, the three areas of high concentration of population, we implemented water quality total reduction in seven terms from 1979, reducing the total quantities of pollutant load of COD, TN and TP. Sea water quality hence has been on an improvement trend as a whole along the steady reduction of pollutants from the land. We however recognize that there are differences in improvement by sea area such as red tide and oxygen-deficient water mass continue to occur in some areas. Meanwhile, it has been pointed out that bio-diversity and bio-productivity should be secured through conservation/creation of tidal flats and seaweed beds in the view point of “Bountiful Sea” To work at these challenges, through the studies depending on the circumstances of the water environment in the enclosed coastal seas, we composed “The Policy of Desirable State of 8th TPLCS” in 2015. We have also added the sediment DO into the water quality standard related to the life-environmental items in view of the preservation of aquatic creatures in the enclosed water areas. Important from now on, along the Policy, is to proceed with necessary measures to improve water quality with good considerations of differences by area in the view point of “Beautiful and bountiful Sea”.

Long Term Monitoring of the Macrobenthos of the Upper Clyde Estuary

1984 ◽  
Vol 16 (5-7) ◽  
pp. 359-373 ◽  
Author(s):  
Anne R Henderson
Keyword(s):  
Water Quality ◽  
Seasonal Variation ◽  
Organic Pollution ◽  
Long Term Changes ◽  
Pollution Loading ◽  
Faunal Density ◽  
History Of ◽  
Long Term Monitoring ◽  
Term Monitoring

The sublittoral macrobenthic invertebrate populations of the Upper Clyde Estuary are described. The estuary has a long history of organic pollution. The long term changes in species composition, faunal density and dominance patterns between 1974 and 1980 are presented. The fauna is dominated by brackish, pollution tolerant oligochaetes and polychaetes. Fluctuations in populations can be related to both seasonal variation in environmental conditions and long term improvements in water quality through a reduction in pollution loading to the estuary.

DEVELOPMENT OF A SIMPLE BENTHIC-PELAGIC COUPLING ECOSYSTEM MODEL AND ITS APPLICATION TO THE REPRODUCTION OF 23YEARS OF WATER QUALITY

2018 ◽  
Vol 74 (4) ◽  
pp. I_511-I_516
Author(s):  
Toshiyuki TAKAO ◽  
Osamu SHIMOZAWA ◽  
Kazuo MURAKAMI ◽  
Ikuo ABE ◽  
Tomonari OKADA ◽  
...  
Keyword(s):  
Water Quality ◽  
Ecosystem Model ◽  
Benthic Pelagic Coupling

scholarly journals Diatom Algae-Indicators of Water Quality in the Lower Zarafshan River, Uzbekistan

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 358
Author(s):  
Sophia Barinova ◽  
Karomat Mamanazarova
Keyword(s):  
Water Quality ◽  
Organic Pollution ◽  
Middle Part ◽  
Pollution Indices ◽  
Distribution Analysis ◽  
State Monitoring ◽  
Ecological Mapping ◽  
Semi Arid Region ◽  
Species Richness And Abundance ◽  
Toxicity Indices

This work is the first, the purpose of which was a comprehensive assessment of the ecological state of the lower reaches of the Zarafshan River using bioindication of water quality by diatoms based on species’ ecological preferences, pollution indices, statistics, and ecological mapping. A total of 198 species and subspecies of diatoms were first identified from 195 samples collected four times a year at six sites in the lower reaches of the Zarafshan River in 2009–2015. The richest species were Cymbella, Navicula, and Nitzschia. Pleurosira laevis, resistant to salinity, was first found in aquatic habitats in Uzbekistan. Bioindicators of nine environmental variables make up 91% of the list. Distribution analysis of variables, pollution indices (SLA—SládečDek index of saprobity), and toxicity indices (WESI—Water Ecosystem State Index) show increases in salinity, turbidity, and decreases in organic pollution downstream. The source of acidification can be the Navoi region. We found an increase in the ability to self-purify with an increase in species richness and abundance of diatoms in the lower part of Zarafshan. Thus, the ecosystem of the studied part of the river successfully copes with the incoming pollution from the middle part of Zarafshan and demonstrates some stability and successful self-purification with a water quality class of 2–3. The first studied lower reaches of the ecosystem of the Zarafshan River using bioindicators, statistics, and ecological mapping show that the problem of aridization in Central Asia does not necessarily lead to degradation of the river ecosystem and an increase in pollution, but with rational water use can improve water quality and self-purification processes. Hence, diatoms can be good indicators of river water quality in a semi-arid region and reflect the climate and anthropogenic load change. We recommend that attention be paid to nutrient and turbidity management and to expand state monitoring points to the lower part of the river up to the Karakul region.

scholarly journals Effect of Acetic Acid and Sodium Bicarbonate Supplemented to Drinking Water on Water Quality, Growth Performance, Organ Weights, Cecal Traits and Hematological Parameters of Young Broilers

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1865
Author(s):  
Yordan Martínez ◽  
Cristopher Isaac Almendares ◽  
Cristhian José Hernández ◽  
Mavir Carolina Avellaneda ◽  
Ana Melissa Urquía ◽  
...  
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Acetic Acid ◽  
Sodium Bicarbonate ◽  
Growth Performance ◽  
Hematological Parameters ◽  
Relative Weight ◽  
Biological Response ◽  
Blood Parameters ◽  
Organ Weights

To evaluate the effect of acetic acid and sodium bicarbonate supplemented to drinking water on water quality, growth performance, relative organ weights, cecal traits and hematological parameters of broilers, a total of 456 one-day-old Cobb MV × Cobb 500 FF mixed broilers were randomly placed in three experimental treatments, with four replicates per treatment and 38 birds per replicate, for 10 days. The treatments consisted of the use of acetic acid (0.4%; T1) as acidifier, an apparently neutral pH (T2) and sodium bicarbonate (1%; T3) as alkalizer of the drinking water. T3 showed the highest values (p < 0.05) for total dissolved solids, electrical conductivity, salinity and pH. T1 and T2 showed the same productive response (p > 0.05); however, T3 decreased (p < 0.05) body weight, feed intake and the relative weight of the pancreas and immune organs and increased (p < 0.05) water intake, mortality and relative weight of the heart and liver. Likewise, T3 increased (p < 0.05) the cecal pH, although without changes for the cecal lactic cecal bacteria count and blood parameters (p > 0.05). The acid pH of the drinking water had no effect on the biological response of broilers compared to T2; however, the T3 provoked high mortality, ascites, low productivity and abnormal growth of some organs.

Seagrass Ecosystems of Andaman and Nicobar Islands: Status and Future Perspective

2020 ◽  
Vol 7 (4) ◽  
pp. 169-174
Author(s):  
Chatragadda Ramesh ◽  
Raju Mohanraju
Keyword(s):  
Water Quality ◽  
Primary Production ◽  
Environmental Changes ◽  
Future Perspective ◽  
Marine Biodiversity ◽  
Seagrass Beds ◽  
Seagrass Meadows ◽  
Seagrass Ecosystem ◽  
Seagrass Ecosystems ◽  
Nicobar Islands

Seagrasses are unique marine flowering plants that play an important ecological role by yielding primary production and carbon sequestration to the marine environment. Seagrass ecosystems are rich in organic matter, supporting the growth of bio-medically important epi and endophytic microorganisms and harbor rich marine biodiversity. They are an essential food source for endangered Andaman state animal Dugongs. Seagrasses are very sensitive to water quality changes, and therefore they serve as ecological bio-indicators for environmental changes. The benthic components in and around the seagrass beds support a significant food chain for other Micro and organisms apart from fishery resources. The epiphytic bacterial communities of the leaf blades support the sustenance against the diseases. Recent reports have shown that the loss of seagrass beds in tropical and temperate regions emphasizes the depletion of these resources, and proper management of seagrass is urgent. The decline of seagrass will impact primary production, biodiversity, and adjacent ecosystems, such as reefs. Therefore, restoring the seagrass meadows could be possible with effective implementing management programs, including seagrass meadows in marine protected areas, restoration projects, seagrass transplantation, implementation of legislative rules, monitoring coastal water quality and human activities in the coastal zone. Lacunas on the seagrass ecosystem management in Andaman & Nicobar Islands are addressed.

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