scholarly journals Seasonal fluctuations of phytoplankton community and physico-chemical parameters of the north western part of the Red Sea, Egypt

2014 ◽  
Vol 40 (4) ◽  
pp. 395-403 ◽  
Author(s):  
Mohamed Z. Nassar ◽  
Hamdy R. Mohamed ◽  
Hanan M. Khiray ◽  
Sarah H. Rashedy
Keyword(s):  
Red Sea ◽  
Phytoplankton Community ◽  
Chemical Parameters ◽  
Seasonal Fluctuations ◽  
The North ◽  
Physico Chemical ◽  
North Western

scholarly journals Assessment of diversity and physico-chemical parameters of cyanobacteria, diatoms and other algal species in the paddy fields of Belagavi district, Karnataka

2020 ◽  
Vol 7 (3) ◽  
pp. 378-382
Author(s):  
Santoshkumar Jayagoudar ◽  
Pradeep Bhat ◽  
Ankita Magdum ◽  
Duradundi Sakreppagol ◽  
Laxmi Murgod ◽  
...  
Keyword(s):  
Algal Species ◽  
Soil Samples ◽  
Chemical Parameters ◽  
Range Estimation ◽  
The North ◽  
Physico Chemical ◽  
Water And Soil Samples ◽  
Study Sites ◽  
Good Range

Algae are the diverse group of organisms in the soil and aquatic environment. The role of them in soil fertility enhancement has been extensively studied worldwide. Belagavi is a tropical agricultural belt in the North Karnataka region with highly fertile soil. Water and soil samples were collected randomly from the paddy field of 15–20 well-distributed spots in 4 selected locations viz Kusumali, Jamboti, Kinaye and Piranwadi. The identification revealed the presence of 94 species and 71 genera in the investigated sites. Among all, 62 species belonged to Bacillariophyceae, 14 species to Chlorophyceae, 10 species to Cyanophyceae, 3 to Xanthophyceae, followed by Trebouxiophyceae and Zygnematophyceae (2 species each) and one species of Ulvophyceae. The maximum number of 62 species was recorded from Kusamali, followed by 49 species in Kinaye, 44 in Jamboti and 35 in Piranwadi. The month of February had the highest number of species (61), decreased to 45 in March, 42 in April and 37 in May. Among the physicochemical parameters analysed for the soil samples, it was found that the pH of the soil is slightly acidic in all the study sites ranged between 5.03–5.85. Further, the electrical conductivity (EC) varied from 0.27–0.345 dS/m, found to be in a good range. Estimation of available micro and macronutrients of soil were measured, and it was found to be at low to moderate levels. The present study indicates the extensive distribution of different classes of algae in the rice fields of four study locations in Belagavi.

scholarly journals Diversity of Phytoplankton and Pollution Tolerant Species of Navule Pond, Shivamogga, Karnataka

2016 ◽  
Vol 15 (4) ◽  
pp. 35-47
Author(s):  
Nafeesa Begum ◽  
H M Ashashree ◽  
H A Sayeswara
Keyword(s):  
Phytoplankton Community ◽  
Winter Season ◽  
Summer Season ◽  
Major Group ◽  
Chemical Parameters ◽  
Phytoplankton Population ◽  
Tolerant Species ◽  
Physico Chemical ◽  
Anabaena Sp

The present study deals with phytoplankton population of Navule pond in Shivamogga during September 2014 to August 2015. Blue-greens constituted the major group (41.75%) followed by Chlorococcalas (36.68%), Diatoms (13.36%), euglenoids (7.35%) and Desmids (0.86%). The phytoplankton community was composed of 11 species of Blue-greens, 20 species of Chlorococcales, 18 species of Diatoms, 11 species of Euglenoids and 08 species of Desmids. Each group of phytoplankton showed different peak periods, the summer season produces relatively more phytoplankton than rainy and winter season. The variations in physico-chemical parameters are responsible for the fluctuation of quantity of phytoplankton.  The dominant genera recorded on the pond were Anabaenopsis sp., Ocillatoria sp., Euglena sp., and Phacus. Some of the pollution tolerant species identified during the present study are Scenedesmusquadricauda, Coelastrum sp., Tetraedonmuticum, Ocillatoria sp., Phormidium sp., Microcystis sp., Anabaena sp., Navicula sp., Synedra ulna, Cyclotella sp., and Pinnularia sp. In the present study Microcystisaeroginosa was recorded indicates the civic pollution.

scholarly journals Physico-Chemical Complex of Matorral Soils of the North Western Region of Algeria

2019 ◽  
Vol 09 (05) ◽  
pp. 134-144
Author(s):  
Fatima Zohra Meftah ◽  
Noury Benabadji ◽  
Abdessamad Merzouk
Keyword(s):  
Western Region ◽  
The North ◽  
Physico Chemical ◽  
Chemical Complex ◽  
North Western

scholarly journals Coupling physics and biogeochemistry thanks to high resolution observations of the phytoplankton community structure in the North-Western Mediterranean Sea

2017 ◽  
Author(s):  
Pierre Marrec ◽  
Andrea M. Doglioli ◽  
Gérald Grégori ◽  
Mathilde Dugenne ◽  
Alice Della Penna ◽  
...  
Keyword(s):  
High Resolution ◽  
Surface Waters ◽  
Phytoplankton Community ◽  
Western Mediterranean ◽  
Fine Scale ◽  
Phytoplankton Community Structure ◽  
The North ◽  
Cold Core ◽  
North Western

Abstract. Fine-scale physical structures and ocean dynamics strongly influence and regulate biogeochemical and ecological processes. These processes are particularly challenging to describe and understand because of their ephemeral nature. The OSCAHR (Observing Submesoscale Coupling At High Resolution) campaign has been conducted in fall 2015 in which, a fine-scale structure in the North Western Mediterranean Ligurian subbasin was pre-identified using both satellite and numerical modeling data. Along the ship track, various variables were measured at the surface (temperature, salinity, chlorophyll-a and nutrients concentrations) with ADCP current velocity. We also deployed a new model of CytoSense automated flow cytometer (AFCM) optimized for small and dim cells, for near real-time characterization of surface phytoplankton community structure of surface waters with a spatial resolution of few km and a hourly temporal resolution. For the first time with this type of AFCM we were able to resolve Prochlorococcus and Synechococcus picocyanobacteria. The vertical physical dynamics and biogeochemical properties of the studied area were investigated by continuous high resolution CTD profiles thanks to a moving vessel profiler (MVP) during the vessel underway associated to a 1-m vertical resolution pumping system deployed during fixed stations. The observed fine-scale feature presented a cyclonic structure with a relatively cold core surrounded by warmer waters. Surface waters were totally depleted in nitrate and phosphate. In addition to the doming of the isopycnals by the cyclonic circulation, an intense wind event induced Ekman pumping. The upwelled subsurface cold nutrient-rich water fertilized surface waters, characterized by an increase in Chl-a concentration. Prochlorococcus, pico- and nano-eukaryotes were more abundant in cold core waters while Synechococcus dominated in warm boundary waters. Nanoeukaryote were the main contributors (> 50 %) in terms of pigment content (FLR) and biomass. Biological observations based on the mean cell's red fluorescence recorded by AFCM combined with physical properties of surface waters suggest a distinct origin for two warm boundary waters. Finally, the application of a matrix growth population model based on high-frequency AFCM measurements in warm boundary surface waters provides estimates of in-situ growth rate and apparent net primary production for Prochlorococcus (μ = 0.21 d−1, NPP = 0.11 mgC m−3 d−1) and Synechococcus (μ = 0.72 d−1, NPP = 2.68 mgC m−3 d−1), which corroborate their opposite surface distribution pattern. The innovative adaptive strategy applied during OSCAHR with a combination of several multidisciplinary and complementary approaches involving high-resolution in-situ observations and sampling, remote-sensing and model simulations provided a deeper understanding of the marine biogeochemical dynamics through the first trophic levels.

Distribution of phytoplankton community in Kotor Bay (south-eastern Adriatic Sea)

2012 ◽  
Vol 7 (3) ◽  
pp. 470-486 ◽  
Author(s):  
Dragana Drakulović ◽  
Branka Pestorić ◽  
Mirko Cvijan ◽  
Slađana Krivokapić ◽  
Nenad Vuksanović
Keyword(s):  
Phytoplankton Community ◽  
Adriatic Sea ◽  
Sampling Period ◽  
Single Species ◽  
Chemical Parameters ◽  
The South ◽  
Phytoplankton Assemblages ◽  
South Eastern ◽  
Physico Chemical ◽  
Shallow Coastal Area

AbstractThe goal of this paper was to explain variability of phytoplankton in a shallow coastal area in relation to physico-chemical parameters. Temporal variability and composition of phytoplankton were investigated in the Kotor Bay, a small bay located in the south-eastern part of the Adriatic Sea. Samplings were performed weekly from February 2008 to January 2009 at one station in the inner part of the Kotor Bay, at five depths (0 m, 2 m, 5 m, 10 m, 15 m). Phosphates, nitrites and nitrates ranged from values under the level of detection to the maximum values of 1.54, 1.53 and 23.91 µmol l−1, respectively. The phytoplankton biomass — represented by chlorophyll a concentration — ranged from 0.12 to 6.78 mg m−3, reaching a maximum in summer. Diatoms were present throughout the whole sampling period, reaching the highest abundance in March (3.42×105 cells l−1at surface). The peak of dinoflagellates in July (2.2×106 cells l−1 at surface) was due to a single species, Prorocentrum micans. The toxic dinoflagellate Dinophysis fortii occurred at a concentration of 2140 cells l−1 in May. The present results of phytoplankton assemblages and distribution provide valuable information for this part of the south-eastern Adriatic Sea where data is currently absent.

scholarly journals Abundance and annual distribution of freshwater snails and some trematode cercariae at Damietta Governorate, Egypt

2021 ◽  
Vol 58 (3) ◽  
pp. 233-247
Author(s):  
M. E. El-Zeiny ◽  
A. M. Ghoneim ◽  
O. A. Abu Samak ◽  
A. A. Khidr
Keyword(s):  
Abiotic Factors ◽  
Species Abundance ◽  
Abundant Species ◽  
Freshwater Snails ◽  
Snail Species ◽  
Chemical Parameters ◽  
Oxygen Conductivity ◽  
The North ◽  
Physico Chemical ◽  
Annual Distribution

Summary In addition to being a good food source, freshwater snails are considered one of the positively and negatively influencing invertebrates on the environment. Several biotic and abiotic factors are thought to affect the distribution and the dynamics of these snails. Freshwater snails are the most dominant and conspicuous individuals of the freshwater biota in Damietta Governorate. In this study, freshwater snails were collected monthly from 5 geographically and environmentally different sites at Damietta Governorate at the north of Egypt during June 2017-May 2018. Seven snail species; Lanistes carinatus, Lanistes varicus, Pila wernei, Segmentorbis angustus, Melanoides tuberculata, Biomphalaria alexandrina, and Gabbiella senoriansis, were identified. Lanistes carinatus was the most abundant species (56.4%) in the collection sites. Besides, Al-Inaniyyah village had the highest snail species abundance and variety. The abundance of the most recorded species varied seasonally; the highest abundance was recorded during summer while the lowest was during winter. The abundance of some snail species correlated positively or negatively with some physico-chemical parameters; water temperature, dissolved oxygen, conductivity, total dissolved salts, and electrical conductivity. Two types of trematode cercariae; gymnocephalus cercariae and xiphidiocercariae, were harvested from Lanistes carinatus. The highest prevalence of both cercarial types was detected during summer. The correlation between the prevalence of both cercarial types and the physico-chemical parameters were determined. Xiphidiocercariae were the most predominant cercarial type in Damietta Governorate. Our findings suggest that the invasion of some freshwater snails is likely to be the cause of the low prevalence or complete absence of some medically important intermediate snail hosts. We recommend further characterization of the distribution of freshwater snails and the interrelationships among them in Egypt, and suggest a controlled use of selected snail species to combat their medically important analogues.

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