scholarly journals Characterization and classification of some intensively cultivated soils from the Ganges river floodplain of Bangladesh

1970 ◽  
Vol 20 (1) ◽  
pp. 71-80 ◽  
Author(s):  
MM Hossain ◽  
ZH Khan ◽  
MS Hussain ◽  
AR Mazumder
Keyword(s):  
Clay Fraction ◽  
Clay Content ◽  
Ganges River ◽  
Soil Series ◽  
River Floodplain ◽  
Alkaline Reaction ◽  
The Family ◽  
The Ganges

Most of the soil samples from four pedons representing some extensive soil series from the Ganges river floodplain of Bangladesh found to be heavy textured with clay content averaging from 43 to 55 per cent up to a depth of one meter. The soils had neutral to alkaline reaction with high percentage of base saturation. Because of seasonal flooding ranging from two - three months the soils have developed redoximorphic features including redox concentration in the middle zone and a redox depletion in the lower zone of the profiles. The seasonal submergence and drying are the most active factors in developing the morphogenetic features in these soils. Smectite was the dominant clay mineral followed by mica and kaolinite with small quantities of vermiculites and interstratified minerals. The minerals in the clay fraction of the soils appear to be inherited from alluvial parent materials with very little in situ mineral transformation. The soils were characterized at the family categoric level of USDA soil taxonomy.Key words: Ganges river floodplain; Characterization; Classification; Cultivated soilsDOI: http://dx.doi.org/10.3329/dujbs.v20i1.8870Dhaka Univ. J. Biol. Sci. 20(1): 71-80, 2011 (January)

scholarly journals Nutrient Elements in Some Benchmark Soil Pedons from the Ganges River Floodplain of Bangladesh

1970 ◽  
Vol 44 (3) ◽  
pp. 359-366
Author(s):  
MM Hossain ◽  
ZH Khan ◽  
MS Hussain
Keyword(s):  
Clay Content ◽  
Nutrient Status ◽  
Soil Characteristics ◽  
Exchange Capacity ◽  
Release Mechanism ◽  
Nutrient Elements ◽  
Ganges River ◽  
Available N ◽  
River Floodplain ◽  
The Ganges

This paper presents the results of chemical analysis of seven selected nutrient elements in soil samples collected from four pedons representing four extensive benchmark soil series from the Ganges river floodplain of Bangladesh. The results of total and available N, P and K contents as well as DTPA (diethelene-triamine pentaacetic acid) -extractable and total Fe, Mn, Cu and Zn contents in the soils were reported. With respect to nutrient status, the soils were rated as fertile with reasonably high production potential under balanced fertilization. The nutrient contents are presumed to be renewed every year by fresh siltation during the monsoon floods. High contents of total iron and potassium in these soils are noteworthy features. Iron in these paddy soils forms redoximorphic features. The release mechanism of K+ from the potash bearing minerals needs further study to determine the need for K fertilization in these soils. The total quantities of the seven studied nutrients in these soils vary widely. In the same way the quantities of extractable (available) nutrients in the soils vary widely. For elements like P, K and Fe less than one percent of the total remain in the available forms. Soil characteristics like organic matter, clay content, cation exchange capacity, pH and lime content have important roles in the availability of nutrients in soils. Keywords: Ganges floodplain, Benchmark soil, DTPA-extractable micronutrients, Soil characteristics DOI: 10.3329/bjsir.v44i3.4411 Bangladesh J. Sci. Ind. Res. 44(3), 359-366, 2009

Advanced Technique for Automatic Detection and Discrimination of a Click Train With Short Interclick Intervals From the Clicks of Ganges River Dolphins (Platanista gangetica gangetica) Recorded by a Passive Acoustic Monitoring System Using Hydrophone Arrays

2014 ◽  
Vol 48 (3) ◽  
pp. 167-181 ◽  
Author(s):  
Harumi Sugimatsu ◽  
Junichi Kojima ◽  
Tamaki Ura ◽  
Rajendar Bahl ◽  
Sandeep Behera ◽  
...  
Keyword(s):  
Acoustic Monitoring ◽  
Ganges River ◽  
Passive Acoustic Monitoring ◽  
Advanced Technique ◽  
Acoustic Data ◽  
Click Train ◽  
Passive Acoustic ◽  
The Ganges

AbstractTo understand the biosonar click characteristics of Ganges river dolphins (adults, young adults, and calves) in a wild environment along with periodic visual observations, an ongoing program for long-term in situ monitoring has been carried out using a passive acoustic monitoring (PAM) system. During monitoring phase 4 (2012), migrating Ganges river dolphin groups with small calves were visually observed, and click trains having a short interclick interval (ICI: from 6 to 12 ms) were concurrently found from the acoustic data corresponding to the period. Click trains having a short ICI have also been observed in other small-toothed whales during foraging and socializing activities (called buzz) (Thoms, Moss, & Vater, 2004; Simard & Mann, 2008). For analysis of the short ICI click trains produced by the Ganges river dolphins, an advanced technique that automatically detects and discriminates a “short ICI click train” from other click sequences during the selected periods of data recorded by a PAM system was developed. For a robust algorithm, a smaller mean ICI caused by overlapping click trains from multiple dolphins that fulfill the range of ICI values that may get incorrectly labeled as “short ICI click train” was considered to judiciously detect a reliable click train. By applying the selected parameters and ICI values (default or given), the performance of the proposed technique was demonstrated using sample data. The results showed the reliability of the technique for the extraction of a variety of short ICI click trains from other click trains.

Development of a handy mobile 4-hydrophone array system for in-situ census of the Ganges river dolphins (platanista gangetica)

2014 ◽  
Author(s):  
Harumi Sugimatsu ◽  
Junichi Kojima ◽  
Tamaki Ura ◽  
Katsunori Mizuno ◽  
Akira Asada ◽  
...  
Keyword(s):  
Ganges River ◽  
Hydrophone Array ◽  
The Ganges

scholarly journals Study of salinity effects on the inorganic phosphorus transformation in three different soil series of Ganges River Floodplain

2016 ◽  
Vol 5 (1) ◽  
pp. 71-79
Author(s):  
Sonia Nasrin ◽  
Tanmoy Kumar Biswas ◽  
Md Sadiqul Amin ◽  
Monowara Khatun
Keyword(s):  
Field Capacity ◽  
Inorganic Phosphorus ◽  
Ganges River ◽  
Soil Series ◽  
Moisture Condition ◽  
Inorganic P ◽  
River Floodplain ◽  
P Transformation ◽  
Exchangeable P ◽  
Phosphorus Transformation

The present study was carried out to investigate the effects of salinity level on different forms of inorganic phosphorus (P) transformation in three different soil series such as Amjhupi, Gopalpur and Bajoa located in Ganges River Floodplain. Two non-saline soils and one slightly saline soil with different textural classes were collected from these sites. The salinity treatments were 0, 6, 10 and 13 dSm-1 with three replications. The treated soils were then incubated in laboratory at field capacity moisture condition. To determine the transformation of different forms of inorganic P, sampling was done for 0, 14, 21, 42 and 84 days. Different forms of inorganic P such as soluble and exchangeable phosphorus (SE-P), iron and aluminium bound phosphorus (Fe and Al-P), calcium bound phosphorus (Ca-P) and residual phosphorus (RE-P) were determined. For Amjhupi soil series, the sequence of different forms of inorganic P was RE-P>Ca-P>Fe and Al-P>SE-P according to their amount. For Gopalpur and Bajoa soil series, the sequence was Ca- P>RE-P>Fe and Al-P>SE-P and RE-P>Ca-P>Fe and Al-P>SE-P, respectively. The sequence clearly indicates that the soluble and exchangeable P decreases with time due to salinity which reduces the uptake of P and ultimately reduces the yield. The changes were statistically significant (p<0.0001) in case of all three soils.Jahangirnagar University J. Biol. Sci. 5(1): 71-79, 2016 (June)

scholarly journals A Study on the Different Forms of Potassium in the Low Ganges River Floodplain Soils of Bangladesh

2014 ◽  
Vol 12 (1) ◽  
pp. 140-147
Author(s):  
MH Rahman ◽  
MM Farazi ◽  
MA Rahman ◽  
MMA Mamun ◽  
K Begum
Keyword(s):  
Critical Level ◽  
Agricultural Research ◽  
Water Soluble ◽  
Soil Science ◽  
Ganges River ◽  
Soil Series ◽  
Critical Limit ◽  
River Floodplain ◽  
Exchangeable K ◽  
Technology Generation

Bangladesh has been divided into 30 Agro ecological Regions (AEZ). Agricultural research, and technology generation and transfer activities have been carried out on this basis. In context of the lack of enough information on different forms of potassium in the soils of the 30 AEZ, an attempt was made to study different forms of potassium of important soils of Bangladesh. As a part of this attempt, an experiment with ten soil samples representing nine different soil series (two of Gopalpur series and one each of Sara, Ishurdi, Ghior, Batra, Sukdebpur, Kumarkhali, Pakuria and Mehendigonj) of the AEZ-12, Low Ganges River Floodplain, was carried out in the Laboratory of the Department of soil science, Bangladesh Agricultural University, Mymensingh to find out the different forms of potassium. The highest value of water soluble potassium (0.08 cmol (+) K g-1) was obtained in Mehendiganj soil series and the lowest value (0.05 cmol (+) K g-1) was obtained in Gopalpur-1, 2 and Ishurdi soil series. The highest amount of exchangeable K (0.29 cmol (+) K g-1) was found in Batra soil series while the lowest (0.13 cmol (+) K g-1) in Gopalpur-1 soil series. The highest amount of available K (0.35 cmol (+) K g-1) was found in both Batra and Mehendiganj soil series while the lowest (0.18 cmol (+) K g-1) in Gopalpur-1 soil series. Considering 0.12 cmol (+) K g-1 as critical limit (BARC, 2012), all soils had available K above the critical level. The highest amount of non-exchangeable K (4.05cmol (+) K g-1) was found in Ghior soil series, while the lowest (2.52 cmol (+) K g-1) was in Mehendiganj soil series. DOI: http://dx.doi.org/10.3329/agric.v12i1.19869 The Agriculturists 2014; 12(1) 140-147

Electron Microscopy of Mycoplasma Pneumoniae

1971 ◽  
Vol 29 ◽  
pp. 258-259 ◽  
Author(s):  
E. S. Boatman ◽  
G. E. Kenny
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Growth Phase ◽  
Hela Cells ◽  
Sulfonic Acid ◽  
Gamma Globulin ◽  
Horse Serum ◽  
Morphological Aspects ◽  
The Family

Information concerning the morphology and replication of organism of the family Mycoplasmataceae remains, despite over 70 years of study, highly controversial. Due to their small size observations by light microscopy have not been rewarding. Furthermore, not only are these organisms extremely pleomorphic but their morphology also changes according to growth phase. This study deals with the morphological aspects of M. pneumoniae strain 3546 in relation to growth, interaction with HeLa cells and possible mechanisms of replication.The organisms were grown aerobically at 37°C in a soy peptone yeast dialysate medium supplemented with 12% gamma-globulin free horse serum. The medium was buffered at pH 7.3 with TES [N-tris (hyroxymethyl) methyl-2-aminoethane sulfonic acid] at 10mM concentration. The inoculum, an actively growing culture, was filtered through a 0.5 μm polycarbonate “nuclepore” filter to prevent transfer of all but the smallest aggregates. Growth was assessed at specific periods by colony counts and 800 ml samples of organisms were fixed in situ with 2.5% glutaraldehyde for 3 hrs. at 4°C. Washed cells for sectioning were post-fixed in 0.8% OSO4 in veronal-acetate buffer pH 6.1 for 1 hr. at 21°C. HeLa cells were infected with a filtered inoculum of M. pneumoniae and incubated for 9 days in Leighton tubes with coverslips. The cells were then removed and processed for electron microscopy.

Three new species, two new genera, and new family Biphragmosagittidae (Сhaetognatha) from Southwest Pacific Ocean

2011 ◽  
Vol 20 (1) ◽  
pp. 161-173
Author(s):  
A.P. Kassatkina
Keyword(s):  
New Species ◽  
Type Species ◽  
Morphological Characters ◽  
The Body ◽  
New Order ◽  
New Genera ◽  
New Family ◽  
The Family ◽  
Three New Species

Resuming published and own data, a revision of classification of Chaetognatha is presented. The family Sagittidae Claus & Grobben, 1905 is given a rank of subclass, Sagittiones, characterised, in particular, by the presence of two pairs of sac-like gelatinous structures or two pairs of fins. Besides the order Aphragmophora Tokioka, 1965, it contains the new order Biphragmosagittiformes ord. nov., which is a unique group of Chaetognatha with an unusual combination of morphological characters: the transverse muscles present in both the trunk and the tail sections of the body; the seminal vesicles simple, without internal complex compartments; the presence of two pairs of lateral fins. The only family assigned to the new order, Biphragmosagittidae fam. nov., contains two genera. Diagnoses of the two new genera, Biphragmosagitta gen. nov. (type species B. tarasovi sp. nov. and B. angusticephala sp. nov.) and Biphragmofastigata gen. nov. (type species B. fastigata sp. nov.), detailed descriptions and pictures of the three new species are presented.

Strategies of In Situ Generated Magnesium Catalysis in Asymmetric Reactions

Synlett ◽  
2021 ◽  
Author(s):  
Dongxu Yang ◽  
Linqing Wang
Keyword(s):  
Asymmetric Synthesis ◽  
Alkaline Earth ◽  
Earth Metal ◽  
Asymmetric Reactions ◽  
Chiral Ligands ◽  
Alkaline Earth Metal ◽  
Enantioselective Reactions ◽  
Earth's Crust

AbstractMagnesium (Mg) is a cheap, non-toxic, and recyclable alkaline earth metal that constitutes about 2% weight in the Earth’s crust. The use of magnesium catalysts to forge chiral moieties in molecules is highly attractive. Based on our work in recent years, we describe the current progress in the development of in situ generated magnesium catalysts and their application in asymmetric synthesis. In this perspective, a critically concise classification of in situ generated magnesium catalytic modes, with relevant examples, is presented, and representative mechanisms of each category are discussed. Building on the established diverse strategies, one can foresee that more innovative and structurally creative magnesium catalysts that are generated in situ will be developed to overcome more formidable challenges of catalytic enantioselective reactions.1 Introduction2 Magnesium Catalysts Generated in Situ from Chiral Ligands Containing Dual Reactive Hydrogens3 Magnesium Catalysts Generated in Situ from Monoanionic Chiral Ligands4 Bimetallic and Polymetallic Magnesium Catalysts Assembled in Situ5 Summary and Outlook

Species-diagnostic and species-specific DNA sequences evenly distributed throughout pine and spruce chromosomes

Genome ◽  
2010 ◽  
Vol 53 (10) ◽  
pp. 769-777 ◽  
Author(s):  
Melanie Mehes-Smith ◽  
Paul Michael ◽  
Kabwe Nkongolo
Keyword(s):  
Dna Sequences ◽  
Random Amplified Polymorphic Dna ◽  
Inter Simple Sequence Repeat ◽  
Issr Markers ◽  
Pinus Monticola ◽  
The Family ◽  
Species Specific ◽  
Rapd And Issr ◽  
Specific Sequences

Genome organization in the family Pinaceae is complex and largely unknown. The main purpose of the present study was to develop and physically map species-diagnostic and species-specific molecular markers in pine and spruce. Five RAPD (random amplified polymorphic DNA) and one ISSR (inter-simple sequence repeat) species-diagnostic or species-specific markers for Picea mariana , Picea rubens , Pinus strobus , or Pinus monticola were identified, cloned, and sequenced. In situ hybridization of these sequences to spruce and pine chromosomes showed the sequences to be present in high copy number and evenly distributed throughout the genome. The analysis of centromeric and telomeric regions revealed the absence of significant clustering of species-diagnostic and species-specific sequences in all the chromosomes of the four species studied. Both RAPD and ISSR markers showed similar patterns.

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