scholarly journals Limnological survey of dhaka-narayanganj-demra (dnd) dam area wetlands

2020 ◽  
Vol 48 (1) ◽  
pp. 93-103
Author(s):  
AHM Shafiullah Habib ◽  
Mahiuddin Sarker ◽  
Md Gias Uddin ◽  
Shimu Akter ◽  
M Niamul Naser
Keyword(s):  
Physicochemical Characteristics ◽  
Fish Production ◽  
Water Parameters ◽  
Fresh Fish ◽  
Average Maximum ◽  
Maximum Water Temperature ◽  
Free Carbon Dioxide ◽  
Maximum Water ◽  
Carbon Dioxide Co2 ◽  
Limnological Survey

Present investigation was conducted to assess the physicochemical characteristics of water and its suitability for fish production at Dhaka-Narayanganj-Demra (DND) dam wetlands. Data were collected at eight points of the study area between March 2014and February 2015on temperature, transparency, pH, dissolved oxygen (DO) and free carbon dioxide (CO2) in the water. The average maximum water temperature, transparency, pH, DO, free CO2, hardness were recorded as34.6±0.4°C, 40.3±0.8cm, 7.9±0.06, 7.6±0.4 mgL-1,85.6±6.6 mgL-1 and 491.2±76mgL-1while minimum average were found as26.3±1.0°C,7.1±0.2 cm, 7.4±0.05, 5.9±0.3 mgL-1, 11.9±0.8 mgL-1 and 87.6±11.3 mgL-1respectively.All the water parameters were found in favourable condition for optimum freshwater fish production with some modification. This study can be the baseline data toward fresh fish supply and production prospect in the Dhaka city at wetland of the DND canal area. Bangladesh J. Zool. 48(1): 93-103, 2020

scholarly journals Physicochemical properties and plankton composition of the river Meghna, Bangladesh

2016 ◽  
Vol 2 (2) ◽  
pp. 324-331 ◽  
Author(s):  
Md Robiul Awal Hossain ◽  
Md Mehedi Hasan Pramanik ◽  
Flura ◽  
Md Istiaque Haidar ◽  
Yahia Mahmud
Keyword(s):  
Dissolved Oxygen ◽  
Physicochemical Properties ◽  
Ammonia Concentration ◽  
Total Alkalinity ◽  
Total Hardness ◽  
Maximum Water Temperature ◽  
Free Carbon Dioxide ◽  
Maximum Water ◽  
Carbon Dioxide Co2 ◽  
Maximum Air Temperature

The present study was conducted to assess the physicochemical properties and plankton composition of water from the river Meghna (Shatnol to Chor Alexander) in thirteen (13) sampling spots during the period of July 2014 to June 2015. Ten (three were physical and seven were chemical) physicochemical parameters of water viz temperature (air and water), transparency, dissolved oxygen (DO), free carbon dioxide (Co2), Conductivity, pH, total hardness, total alkalinity and ammonia (NH3), plankton community of both phytoplankton and zooplanktons were studied in aforesaid 13 sampling spots of the river Meghna. Maximum air temperature was recorded 37°C at Ananda Bazar. Maximum water temperature was recorded 30°C at Kaligonj, Chor Ludhua and Chor Alexander area of the river Meghna. Transparency was found minimum 12 cm at Chor Ludhua and maximum 75 cm at Horina Ghat. The concentration of dissolved oxygen was found maximum at Chor Voirabi and Horina Ghat 7.3 mg/l and was found minimum at Kaligonj 3.5 mg/l. Free CO2 was found highest at Kaligonj 17 mg/l and lowest at Horina Ghat 5 mg/l. pH was found ranged from almost neutral to alkaline (Minimum 7.2 to Maximum 9). Total hardness was found highest at Chor Alexander 802 mg/l and lowest at Eklaspur 35 mg/l. Total alkalinity was found highest at Chor Alexander 145 mg/l and found minimum at Madrasa Ghat and Hizla 29 mg/l. Conductivity was found highest at Chor Alexander and Chor Ludhua 1000 ?s/cm. Ammonia concentration was found ranged from 0.00 to 0.03mg/l. The mean contribution of phytoplankton was about 90.5% of the total planktonic organisms and zooplankton contributed the rest. The major groups of phytoplankton were found Bacillariophyceae, Chlorophyceae, Cyanophyceae, Dinophyceae, Euglenophyceae, Myxophyceae and Xanthophyceae. Total 9 genera of zooplankton were identified from four families namely Rotifera with 2 genera, Cladocera with 3 genera, Copepoda with 3 genera and Ostracoda with 1 genus from the selected sampling spots.Asian J. Med. Biol. Res. June 2016, 2(2): 324-331

scholarly journals Some limnological characteristics of Dhaka-Narayangonj-Demra dam canal, Bangladesh

2015 ◽  
Vol 41 (2) ◽  
pp. 257-264 ◽  
Author(s):  
AHM Shafiullah Habib ◽  
M Mahbub Alam ◽  
Suraiya Mahjabeen ◽  
M Niamul Naser
Keyword(s):  
Ph Value ◽  
Quality Parameters ◽  
Maximum Amount ◽  
Sampling Points ◽  
Maximum Water Temperature ◽  
Free Carbon Dioxide ◽  
Maximum Water ◽  
One Year ◽  
Fair Average ◽  
Limnological Parameters

Some limnological parameters of water of Dhaka-Narayongonj-Demra (DND) dam canal were studied for one year period from May 2010 to April 2011. Sampling points were selected on the basis of human activities around the dam. The maximum water temperature was recorded in May 2010 (31.5 ± 0.2041°C) and minimum in December 2010 (18.3 ± 0.1925°C). Water transparency was highest in February 2011(38.1 ± 3.48 cm) and lowest in May 2010 (24.56 ± 2.722 cm). The maximum concentration of dissolved oxygen (DO) was found in winter month December 2010 (6.83 ± 0.4735 mg/l) and the minimum in summer month May 2010 (4.00 ± 0.2378 mg/l). The BOD was highest in August (34 ± 0.122 mg/l) and lowest in January (15 ± 0.274 mg/l). The highest amount of free carbon dioxide (free CO2) was recorded as 29.67 ± 4.4514 mg/l in January 2011 and the lowest 3.81 ± 0.8972 mg/l in August 2010. Maximum amount of hardness was found in December 2010 (271.20 ± 94.6597 mg/l) and minimum in September 2010 (196.20 ± 66.3963 mg/l) with a year round average of 229.51 ± 7.82 mg/l. pH was found fair (average 7.15 ± 0.08) during the study period. Maximum pH value 7.66 ± 0.14420 was recorded in the month of August while the minimum 6.74 ± 0.0574 in the month of May 2010. Although some water quality parameters of DND canal were found to be suitable for aquaculture but it was organically polluted. Further investigation on the heavy metal pollution is necessary before using the water and crops produced from DND canal for anthropological use.Bangladesh J. Zool. 41(2): 257-264, 2013

scholarly journals EFFECT OF DEFOLIATION ON THE YIELD AND QUALITY OF ‘PRATA COMUM’ BANANA FRUITS

2017 ◽  
Vol 39 (3) ◽  
Author(s):  
JULIANA DOMINGUES LIMA ◽  
JÉSSICA ANDRADE FLORENCIO ◽  
WILSON DA SILVA MORAES ◽  
SILVIA HELENA MODENESE GORLA DA SILVA ◽  
EDUARDO NARDINI GOMES ◽  
...  
Keyword(s):  
Chemical Control ◽  
Fruit Size ◽  
Physicochemical Characteristics ◽  
Black Sigatoka ◽  
Yield And Quality ◽  
Period 2 ◽  
Average Maximum ◽  
Number Of Leaves ◽  
Banana Crops

ABSTRACT With the advent of black sigatoka in commercial banana crops in the “Vale do Ribeira” region, state of São Paulo, the monitoring the severity and chemical control of the disease in susceptible varieties have become more frequent in order to avoid leaf loss. This study simulated the effect of defoliation caused by the disease on the yield and quality of ‘Prata Comum’ banana fruits, depending on the formation period and fruit position in the bunch. The experimental design was completely randomized in a 2 x11 factorial scheme (period of bunch formation x number of leaves at flowering), 6-16 leaves at flowering in two periods of bunch formation with six replicates. In Period 1, flowering occurred at 04/15/13 and in Period 2 at 01/07/14, although in Period 1, bunch mass was higher and in Period 2, higher average maximum and minimum daily temperatures, precipitation and radiation were observed. Regardless of formation period, the number of leaves at flowering affected bunch mass, which ranged from 18 to 23 kg plant-1. Defoliation affected the size of fruits of hand 1 and last hand of the bunch, but not the variability in fruit size due to the position the fruit occupies in the bunch and physicochemical characteristics.

scholarly journals Environmental Variables of the Seti Gandaki River Basin Pokhara, Nepal

2018 ◽  
Vol 22 (2) ◽  
pp. 129-139 ◽  
Author(s):  
Kishor Kumar Pokharel ◽  
Khadga Bahadur Basnet ◽  
Trilok Chandra Majupuria ◽  
Chitra Bahadur Baniya
Keyword(s):  
Water Temperature ◽  
River Basin ◽  
Environmental Variables ◽  
Temporal Variations ◽  
Total Alkalinity ◽  
Urban Site ◽  
Water Conductivity ◽  
Free Carbon Dioxide ◽  
Spatio Temporal ◽  
Carbon Dioxide Co2

Present paper focuses on the spatio-temporal variations and correlations among the environmental variables of the Seti Gandaki River basin, Pokhara, Nepal. A total of five sites, three along the river and two in tributaries were selected for this study. Water sampling was done fortnightly for environmental variables following standard methods during July 2011 to June 2012. Mean and standard deviation of the environmental variables revealed that the depth (0.9 ± 0.3), pH (8 ± 0.4), total phosphates (PO4) (0.10 ± 0.03) and nitrates (NO3) (0.13 ± 0.04) were normally variable among the sites. But the discharge (40.00 ± 37.00), width (32.30 ± 13.00), turbidity (81.40 ± 51.00), transparency (29.10 ± 15.00), conductivity (166.00 ± 80.00), water temperature (18.00 ±4.00), dissolved oxygen (DO) (8.00 ± 2.00), free carbon dioxide (CO2) (7.00 ± 2.00) and total alkalinity (98.00 ± 22.00) varied among sites equally. Correlation coefficient between the sites and environmental variables revealed that sites were found significantly correlated with water conductivity (r2 = 0.6), DO (r2 = -0.52), and free CO2 (r2 = 0.6); depth of water with width (r2 = 0.94), discharge (r2 = 0.96), turbidity (r2 = 0.71), transparency (r2 = -0.62), water temperature (r2 = 0.60), pH (r2 = -0.52) and DO (r2 = -0.48); water temperature with pH (r2 = -0.54), DO (r2 = -0.79), free CO2 (r2 = 0.69), total alkalinity (r2 = -0.58), total PO4 (r2 = 0.54) and NO3 (r2 = 0.62), etc. The enhancement of turbidity, conductivity, free CO2, phosphates and nitrates, while, suppression of transparency, pH and DO at the urban site indicated the urban influence. Journal of Institute of Science and TechnologyVolume 22, Issue 2, January 2018, page: 129-139

scholarly journals Experimental analysis of Scheffler reflector water heater

2011 ◽  
Vol 15 (3) ◽  
pp. 599-604 ◽  
Author(s):  
Rupesh Patil ◽  
Gajanan Awari ◽  
Mahendra Singh
Keyword(s):  
Storage Tank ◽  
Large Diameter ◽  
Average Power ◽  
Water Heater ◽  
Average Value ◽  
Water Boiling Test ◽  
Maximum Water Temperature ◽  
Maximum Water ◽  
Set Up ◽  
And Storage

The performance of Scheffler reflector has been studied. In this system storage reservoir was installed at Focus point. It has a single large diameter drum which serves the dual purpose of absorber tube and storage tank. The drum is sized to have a storage capacity of 20 liter for experiment. The tests were carried out with this set up and were repeated for several days. Performance analysis of the collector has revealed that the average power and efficiency in terms of water boiling test to be 1.30 kilowatts and 21.61 % respectively against an average value of beam radiations of 742[Wm-2]. The maximum water temperature in the storage tank of 98?C has been achieved on a clear day operation and ambient temperature between 28?C to 31?C.

scholarly journals What causes cooling water temperature gradients in forested stream reaches?

2014 ◽  
Vol 11 (6) ◽  
pp. 6441-6472 ◽  
Author(s):  
G. Garner ◽  
I. A. Malcolm ◽  
J. P. Sadler ◽  
D. M. Hannah
Keyword(s):  
Water Temperature ◽  
Water Column ◽  
Stream Temperature ◽  
Temperature Gradients ◽  
Daily Maximum ◽  
Net Energy ◽  
Net Radiation ◽  
Maximum Water Temperature ◽  
Maximum Water ◽  
Energy Gains

Abstract. Previous studies have suggested that shading by riparian vegetation may reduce maximum water temperature and provide refugia for temperature sensitive aquatic organisms. Longitudinal cooling gradients have been observed during the daytime for stream reaches shaded by coniferous trees downstream of clear cuts, or deciduous woodland downstream of open moorland. However, little is known about the energy exchange processes that drive such gradients, especially in semi-natural woodland contexts, and in the absence of potentially confounding cool groundwater inflows. To address this gap, this study quantified and modelled variability in stream temperature and heat fluxes along an upland reach of the Girnock Burn (a tributary of the Aberdeenshire Dee, Scotland) where riparian landuse transitions from open moorland to semi-natural forest. Observations were made along a 1050 m reach using a spatially-distributed network of ten water temperature micro-loggers, three automatic weather stations and >200 hemispherical photographs, which were used to estimate incoming solar radiation. These data parameterised a high-resolution energy flux model, incorporating flow-routing, which predicted spatio-temporal variability in stream temperature. Variability in stream temperature was controlled largely by energy fluxes at the water column–atmosphere interface. Predominantly net energy gains occurred along the reach during daylight hours, and heat exchange across the bed-water column interface accounted for <1% of the net energy budget. For periods when daytime net radiation gains were high (under clear skies), differences between water temperature observations decreased in the streamwise direction; a maximum difference of 2.5 °C was observed between the upstream reach boundary and 1050 m downstream. Furthermore, daily maximum water temperature at 1050 m downstream was ≤1°C cooler than at the upstream reach boundary and lagged the occurrence of daily maximum water temperature upstream by >1h. Temperature gradients were not generated by cooling of stream water, but rather by a combination of reduced rates of heating in the woodland reach and advection of cooler (overnight and early morning) water from the upstream moorland catchment. Longitudinal thermal gradients were indistinct at night and on days when net radiation gains were low (under over-cast skies), thus when changes in net energy gains or losses did not vary significantly in space and time, and heat advected into the reach was reasonably consistent. The findings of the study and the modelling approach employed are useful tools for assessing optimal planting strategies for mitigating against ecologically damaging stream temperature maxima.

scholarly journals Modern problems in assessment of hydraulic resistance

2021 ◽  
Vol 258 ◽  
pp. 02006
Author(s):  
Igor Sikarev ◽  
Tatiana Vekshina ◽  
Vladimir Bolshakov ◽  
Ekaterina Korinets ◽  
Artem Butsanets
Keyword(s):  
Hydraulic Resistance ◽  
Hydraulic Characteristics ◽  
Lowland Rivers ◽  
Independent Field ◽  
Average Maximum ◽  
Maximum Water ◽  
Field Information ◽  
Direct Approximation ◽  
Determining Factor

The paper is devoted to the analysis of modern problems in assessment of hydraulic resistance. The obtained formulas for calculating the roughness coefficients and other interrelated hydraulic parameters of the channel are given. As a determining factor for the systemic characteristics of flows, N.A. Rzhanitsyn used the average long-term and average maximum water discharges, and the authors of this work proposed the use of these characteristics in accordance with the watershed area A in km2 of the subsequently derived dependences for unexplored rivers. Thanks to this approach, it became possible to obtain information by cartographic methods. Direct approximation of these data gives an expression for the flow order. The formulas obtained can be used to calculate the hydraulic characteristics of lowland rivers. For the European territory of Russia, the formulas have been tested using independent field information. However, the authors believe that the formulas will successfully work for other even lands as well. The formulas are simple and easy to calculate using software. In the future, it is planned to use specialized software for processing calculations and use the obtained results in the geographic information system.

Development of methods for accounting costs and evaluation of products in organizations of pond fishing

2020 ◽  
pp. 25-35
Author(s):  
Rolan Alborov ◽  
Ekaterina Mosunova ◽  
Oksana Zlobina
Keyword(s):  
Fish Farming ◽  
Cost Accounting ◽  
Fair Value ◽  
Production Costs ◽  
Fish Production ◽  
Fresh Fish ◽  
The Cost ◽  
Methodological Aspects

Pond fish farming is of great importance in meeting the needs of the population with fresh fish, that is, food independence and security. Therefore, the issues of accounting for production costs and evaluating fish production in the system for managing the effectiveness of pond fish farming development are becoming relevant in modern conditions. In this regard, substantiated the provisions that determine the organizational and methodological aspects of accounting and evaluation support for the management of fish farming production. Technological redistribution is defined as objects of cost accounting and output of pond fish farming products. A model is proposed for organizing an alternate cost accounting method, which are grouped in relation to the volume of production and costing items. Costing units and costing objects in pond fish farming have been established. Methods have been developed for determining the cost and fair value of the relevant types of fish farming products, as well as methods for accounting for costs and output in pond fish farming.

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