scholarly journals Ichthyofaunal Diversity and Water Quality in the Kangsabati Reservoir, West Bengal, India

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Amalesh Bera ◽  
Manojit Bhattacharya ◽  
Bidhan Chandra Patra ◽  
Utpal Kumar Sar
Keyword(s):  
Water Quality ◽  
West Bengal ◽  
Inorganic Nitrogen ◽  
Conservation Status ◽  
Limiting Factor ◽  
Monthly Basis ◽  
Water Parameters ◽  
Total Inorganic Nitrogen ◽  
Data Deficient ◽  
High Chloride

The ichthyofauna in relation to water quality was studied on monthly basis from March, 2010 to February, 2011 in the Kangsabati Reservoir, West Bengal. The study revealed that physicochemical parameters of Kangsabati Reservoir were congenial for 39 fish species of commercial importance, belonging to 7 orders, 15 families, and 26 genera. The Cypriniformes were dominant with 17 species, followed by Siluriformes and Perciformes, with 7 species each, Channiformes with 3 species, Osteoglossiformes and Synbranchiformes with 2 species each, and Anguilliformes with 1 species. Regarding their conservation status, 27 species were of least concern, 1 species was vulnerable, 6 species were near threatened, 1 species was data deficient, and 4 species were not evaluated (IUCN-Version 2014.1). Economical values have also been evaluated. Water parameters such as temperature, pH, alkalinity, dissolved oxygen, hardness, free CO2, salinity, total inorganic nitrogen, and phosphate were recorded and found suitable for fish production. Conductivity, transparency, and high chloride level are minor limiting factor that may needs rectification for improved fisheries management.

Development of Air Supply Control Technology in Sidestream MLE Process by Measuring Conductivity

2020 ◽  
Vol 42 (3) ◽  
pp. 97-109
Author(s):  
Shinyo Chang ◽  
Pung Shik Shin ◽  
Yeon-Koo Jeong ◽  
Young June Choi
Keyword(s):  
Water Quality ◽  
Removal Efficiency ◽  
Biological Treatment ◽  
Inorganic Nitrogen ◽  
Ammonia Nitrogen ◽  
Control Technology ◽  
Treatment Efficiency ◽  
Air Supply ◽  
Total Inorganic Nitrogen ◽  
Nitrogen Treatment

Objectives : This study aimed to achieve improved process performance and energy saving by developing a technology to control the air supply of an aerobic basin by measuring the conductivity in the anoxic basin.Methods : To verify whether conductivity can be used as an operation indicator of biological treatment, the correlation analysis between water quality factor and conductivity of each process was conducted by dividing into summer (methanol input), winter and autumn periods. An empirical formula was presented by briefly arranging the required air quantity formula, and a quick reference was prepared by putting air supply in the conductivity range sequentially. The performance evaluation was judged based on the removal efficiency of ammonia nitrogen and total inorganic nitrogen, SNR and SDNR, the change of air supply, the stability of the process against inflow change.Results and Discussion : The seasonal correlation coefficients of conductivity and water quality items were calculated in the order of ammonia nitrogen, total inorganic nitrogen, DOC, and phosphate in the range of 0.5267 ~ 0.9115. It was found that the conductivity could be used as an operation indicator of the biological treatment process with a correlation coefficient of 0.5 or more. The regression equations for the conductivity and ammonia nitrogen are secured by season, so it is possible to estimate the ammonia nitrogen through the conductivity. At the end of the aerobic basin DO was 3.4 mg/L, the nitrogen treatment efficiency in winter was the best. The aerobic basin DO can be controlled by the air supply, and it can be seen that it is possible to control the air supply and improve the nitrogen treatment efficiency by directly measuring the conductivity having a high correlation with nitrogen. An empirical formula for estimating the required air volume through conductivity and inflow is presented. A' and (B' + X') are 0.0589 (m<sup>3</sup>-air/h)/(m<sup>3</sup>/h)/(μS/cm) and –77.562 (m<sup>3</sup>-air/h)/(m<sup>3</sup>/h). The result of automatic control of air supply according to the measured conductivity of anoxic tank during winter season showed that total inorganic nitrogen removal efficiency and SDNR were 8.3% and 0.007 g-N/g-MLSS/d higher than the actual plant conditions, respectively. During the automatic control period, the air supply/inflow average ratio was 36 (m<sup>3</sup>-air/h)/(m<sup>3</sup>/h), which could reduce the air supply by 21.7% compared to the actual plant conditions.Conclusions : The air supply can be estimated from the flow rate and conductivity. The air supply control technology of the conductivity-based MLE process will be able to simultaneously improve nitrogen removal efficiency and reduce energy consumption.

Heterogeneity of water quality signature and feedbacks to carbon sequestration in wetlands across some districts of West Bengal, India

2019 ◽  
Vol 11 (2) ◽  
pp. 434-450
Author(s):  
B. B. Jana ◽  
S. K. Nandy ◽  
S. Lahiri ◽  
J. N. Bhakta ◽  
J. K. Biswas ◽  
...  
Keyword(s):  
Water Quality ◽  
Inorganic Carbon ◽  
West Bengal ◽  
Dissolved Inorganic Carbon ◽  
Inorganic Nitrogen ◽  
Information Criterion ◽  
Total Alkalinity ◽  
Biological Interactions ◽  
Ph Conditions ◽  
Measured Water

Abstract Water quality measurements can indicate carbon status or algal biomass. Microalgae have an excellent ability to utilize all forms of dissolved inorganic carbon at different pH conditions. Water quality signature (WQS) using three different expressions with (i) pH; (ii) total alkalinity, hardness and total dissolved solids; and (iii) nitrate and conductivity of water was assessed in 32 wetlands distributed across 5 districts of West Bengal, India. Two zones were clearly discernible: coldwater (15–23 °C) high-altitude lakes in Darjeeling, and tropical (31–32 °C) low-altitude wetlands. Multivariate analysis of the Akaike information criterion (ACI) model revealed location-specific variability of agro-climatic and biogeochemical interactions. Dissolved inorganic carbon and inorganic nitrogen appeared to be important in regulating the phytocarbon content of microalgae. The wetlands located in the Gangetic alluvial tropical or semi-coastal areas (Hooghly, 24-Parganas, Nadia, Midnapore) were alkaline (pH = 7.52–7.97) where half-bound carbon dioxide comprised the major component (18–26%) of total inorganic carbon, with moderate to eutrophic (PO4-P− 0.16–0.23 mg/l) states which have a negative feedback to global warming. The heterogeneity of measured water quality signature consolidated the sanative nature of wetlands for their complex functional attributes with agro-climatic, biogeochemical and soil-water-biological interactions.

scholarly journals Cold water fish diversity and their conservation status in Teesta,Jaldhak, Torsa, Kaljani and Sankosh Rivers of the Dooars region, West Bengal, India

2021 ◽  
Vol 10 (1) ◽  
pp. 146-152
Author(s):  
Tapan Sarkar ◽  
Keyword(s):  
Fish Species ◽  
West Bengal ◽  
Cold Water ◽  
Conservation Status ◽  
Fish Diversity ◽  
Vulnerable Species ◽  
Monthly Basis ◽  
Water Fish

A survey was conducted on the cold water fish diversity in the different rivers of the Dooars region with the help of fisherman. Data was collected on the monthly basis by using different nets. A total of 71 cold water fishes were reported during the study period. Most dominant family was cyprinidae with 32 species followed by Sisoridae with 12 species; Balitoridae 8 and Bagridae with 4 species etc. 70 cold water fish species in the river Teesta, 63 in Jaldhaka, 66 in Torsa, 61 in Kaljani and 66 in the river Sankosh were recorded. Ten Endangered and 31 Vulnerable species were reported from all the five rivers. Out of 71 cold water fishes many have consumption and ornamental value. Many migratory and sport cold water fishes are also reported. Catch frequency status indicates many fishes found rare and extremely rare during the study.

DIP quality influenced by process water quality

TAPPI Journal ◽  
2014 ◽  
Vol 13 (9) ◽  
pp. 51-60
Author(s):  
DENNIS VOSS ◽  
HANS-JOACHIM PUTZ ◽  
SAMUEL SCHABEL
Keyword(s):  
Water Quality ◽  
Surface Tension ◽  
Ph Value ◽  
Water Hardness ◽  
Process Water ◽  
Test Results ◽  
Negative Effects ◽  
Water Parameters ◽  
Effects Of Ph ◽  
Contamination Levels

The need for deinking mills to reduce their fresh water consumption has resulted in higher loads of various contaminants in the process water. Lower recovered paper quality also leads to higher contamination levels in the mills. This higher load has an influence on achievable target brightness. The objective of the work was to determine and explain the main reasons for relatively poor deinked pulp quality or poor deinking potential based on the influence of recovered paper composition and process water quality. The process water parameters significantly affect the deinking potential of recovered paper. The test results showed the negative effects of increased water hardness. For standard recovered paper mixtures, flotation selectivity is higher with increasing flotation pH-value. Good results were realized for standard recovered paper with low hardness, low surface tension, and high pH-value. The results for recovered paper containing flexo newsprint could be slightly improved with low hardness, low surface tension, and low pH-value. The results of the test program using design of experiments showed interacting effects of pH-value and surface tension on luminosity and flotation selectivity.

scholarly journals Global extinction risk for seahorses, pipefishes and their near relatives (Syngnathiformes)

Oryx ◽  
2021 ◽  
pp. 1-10
Author(s):  
Riley A. Pollom ◽  
Gina M. Ralph ◽  
Caroline M. Pollock ◽  
Amanda C.J. Vincent
Keyword(s):  
Threatened Species ◽  
Habitat Degradation ◽  
Extinction Risk ◽  
Conservation Status ◽  
Field Research ◽  
Selective Extraction ◽  
Iucn Red List ◽  
Point Estimate ◽  
Conservation Action ◽  
Data Deficient

Abstract Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are seahorses (Hippocampus spp.: 14/42 species, with an additional 17 that are Data Deficient) or freshwater pipefishes of the genus Microphis (2/18 species, with seven additional that are Data Deficient). Two species are Near Threatened. Nearly one-third of syngnathiformes (97 species) are Data Deficient and could potentially be threatened, requiring further field research and evaluation. Most species (61%) were, however, evaluated as Least Concern. Primary threats to syngnathids are (1) overexploitation, primarily by non-selective fisheries, for which most assessments were determined by criterion A (Hippocampus) and/or (2) habitat loss and degradation, for which assessments were determined by criterion B (Microphis and some Hippocampus). Threatened species occurred in most regions but more are found in East and South-east Asia and in South African estuaries. Vital conservation action for syngnathids, including constraining fisheries, particularly non-selective extraction, and habitat protection and rehabilitation, will benefit many other aquatic species.

Diplodia rosarum. [Descriptions of Fungi and Bacteria].

2011 ◽  
Author(s):  
V. P. Hayova
Keyword(s):  
New York ◽  
South Carolina ◽  
Czech Republic ◽  
Geographical Distribution ◽  
West Bengal ◽  
Conservation Status ◽  
Uttar Pradesh ◽  
Republic Of Georgia ◽  
Irish Republic ◽  
Botryotinia Fuckeliana

Abstract A description is provided for Diplodia rosarum, which has been implicated in canker or dieback of cultivated roses. Some information on its dispersal and transmission and conservation status is given, along with details of its geographical distribution (USA (California, Massachusetts, New York, Ohio, South Carolina, Texas), Brazil, Azerbaijan, Republic of Georgia, India, (Delhi, Uttar Pradesh, West Bengal), Kyrgyzstan, Pakistan, Cuba, Belgium, Bosnia-Hercegovina, Bulgaria, Czech Republic, Denmark, Estonia, France, Germany, Greece, Irish Republic, Italy, Moldova, Netherlands, Poland, Portugal, Romania, Russia, Slovakia, Sweden, Ukraine and UK), hosts (Rosa arvensis, R. banksiana, R. canina, R. centifolia, R. corymbifera, R. hybrida, R. multiflora, R. spinosissima, R. tomentosa, R. willmottiae and Rosa sp.) and associated fungi (Botryotinia fuckeliana, Hendersonula sp., Macrophoma camarana, Microdiplodia rosarum, Coniothyrium olivaceum, Pleospora herbarum f. microspora and Valsa ambiens).

scholarly journals Simulation of denitrification and ozone loss for the Arctic winter 2002/2003

2005 ◽  
Vol 5 (6) ◽  
pp. 1437-1448 ◽  
Author(s):  
J.-U. Grooß ◽  
G. Günther ◽  
R. Müller ◽  
P. Konopka ◽  
S. Bausch ◽  
...  
Keyword(s):  
Inorganic Nitrogen ◽  
Potential Temperature ◽  
Three Dimensional ◽  
Lagrangian Model ◽  
The Arctic ◽  
Particle Nucleation ◽  
Ozone Loss ◽  
Dimensional Version ◽  
Total Inorganic Nitrogen ◽  
Catalytic Cycles

Abstract. We present simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) for the Arctic winter 2002/2003. We integrated a Lagrangian denitrification scheme into the three-dimensional version of CLaMS that calculates the growth and sedimentation of nitric acid trihydrate (NAT) particles along individual particle trajectories. From those, we derive the HNO3 downward flux resulting from different particle nucleation assumptions. The simulation results show a clear vertical redistribution of total inorganic nitrogen ( ), with a maximum vortex average permanent removal of over 5ppb in late December between 500 and 550K and a corresponding increase of of over 2ppb below about 450K. The simulated vertical redistribution of is compared with balloon observations by MkIV and in-situ observations from the high altitude aircraft Geophysica. Assuming a globally uniform NAT particle nucleation rate of 7.8x10-6cm-3h-1 in the model, the observed denitrification is well reproduced. In the investigated winter 2002/2003, the denitrification has only moderate impact (≤14%) on the simulated vortex average ozone loss of about 1.1ppm near the 460K level. At higher altitudes, above 600K potential temperature, the simulations show significant ozone depletion through -catalytic cycles due to the unusual early exposure of vortex air to sunlight.

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